Simonova, Yulia Aleksandrovna

Timofeeva L.M., Simonova Y.A., Eremenko I.V., Filatova M.P., Topchiy M.A., Kozobkova N.V., Shleeva M.O., Eropkin M.Y.

A series of antimicrobial protonated diallylammonium polymers, poly(diallylammonium trifluoroacetate) (PDAATFA), were synthesized by classical polymerization, using an especially elaborated method for preparation of polymers with low molecular weight (MW), and by RAFT polymerization, with different end groups in a range of MW values of (8–43) × 103 g∙mol−1. Cytotoxicity relative to eukaryotic cells (epithelioid lines A-549 and MA-104) and bactericidal activity of the polymers (relative to Pseudomonas aeruginosa and Staphylococcus aureus) are investigated. The effect of the end groups and MW on toxicity and bactericidal activity is shown. Dependence of the activity and, most of all, cytotoxicity on MW is preserved even at a small difference in MW values in the MW range of (18–40) × 103 g·mol−1. A clear dependence of the studied properties on the nature of the terminal group is revealed. Sulfate -O-S(=O)2-O¯ end group has a noticeable effect on the bactericidal efficiency and smaller influence on toxicity, while dithiocarbonyl end group -S-C(=S)-O-CH2-CH3 has a significant effect on efficiency and especially toxicity, drastically increasing the latter. Overall, based on the results obtained, polymers PDAATFA of low MW are considered promising antimicrobial agents for the creation of new transdermal drugs.

Eremenko I., Simonova Y., Filatova M., Yevlampieva N., Bondarenko G., Kleshcheva N., Timofeeva L.

Protonated diallylammonium polymers attract attention due to a number of properties, in particular high antimicrobial activity, including activity against the mycobacterium M. tuberculosis. To reduce the cytotoxic effect of polymers in the case of practical use, samples with a low MW are required. The work investigated the free radical polymerization of protonated diallylammonium monomers, diallylammonium trifluoroacetates, in excess of the initiator ammonium persulfate (10–1 M) and at average polymerization temperatures (40 and 50°C) to obtain polymers with a low degree of polymerization. It has been shown that under such conditions it is possible to obtain polymers with values suitable within the aim: 16000 < MW < 28000 g/mol. Using NMR and IR spectroscopy, it was shown that with an increase in the concentration of the initiator and, accordingly, a decrease in the molecular mass of polymers, the relative number of characteristic terminal vinyl groups decreases, and the terminal groups formed by the interaction of macroradicals with primary radicals of the initiator become predominant, in this case, sulphate groups of ammonium persulfate. The data obtained indicate that at high concentrations of the initiator, the characteristic reactions of chain transfer to the monomer are largely kinetically suppressed by the interactions of macroradicals with the primary radicals of the initiator. The approach used, which makes it possible to synthesize polymers with a low MW and terminal groups of the initiator, can be applicable in the future to vary the properties of antimicrobial activity and toxicity of polymers.

Yevlampieva N. ., Vezo O. ., Slyusarenko M. ., Gubarev A. ., Simonova Y. ., Eremenko I. ., Topchiy M. ., Timofeeva L. .

Protonated diallylammonium polymers are special among cationic polyelectrolytes, due to a series of properties including high antimicrobial activity, for example, towards Mycobacterium tuberculosis. The polymers samples should be characterized properly for their practical application. In this study, protonated secondary polydiallylamines based on diallylammonium trifluoroacetate have been synthesized via radical reversible addition−fragmentation chain-transfer polymerization in the presence of 2-[(ethoxycarbonothioyl)sulfanyl]acetic acid. The NMR spectroscopy data have shown that the macromolecules contain the dithiocarbonyl terminal groups enhancing the polymer solubility in nonaqueous media, for instance, in methanol. The obtained polymers have been investigated by means of hydrodynamics and dynamic light scattering methods; molecular mass and hydrodynamic parameters of the macromolecules have been determined. Comparison of the polymers with similar ones synthesized via conventional radical polymerization and bearing terminal vinyl groups has revealed the independence of their hydrodynamic properties in 1.0 mol/L NaCl on the synthesis method and the terminal groups structure at М > 8 × 103, thus allowing the application of the scaling relationships for the diallylammonium polymers to determine the molecular mass, irrespectively on the preparation methods.

Timofeeva L., Bondarenko G., Nikitushkin V., Simonova Y., Topchiy M., Eremenko I., Shleeva M., Mulyukin A., Kaprelyants A.

• Protonated polydiallylamines exhibit biocidal action on M. smegmatis. • It was proved direct interaction of polymers with the molecules of outer membrane. • Protonated polydiallylamines bind to phenolic glycolipids via non-covalent complex. • Hydrogen bonding gives the main contribution to the energy of complexation. • Rigid cell wall of M. smegmatis is vulnerable to protonated polydiallylamines. The protonated diallylammonium polymers (PDAA) are known to possess a high antimicrobial activity relative to a broad scope of pathogens, unlike their quaternary analog poly( N, N -diallyl- N, N -dimethylammonium chloride) (PDADMAC). Moreover, PDAA exhibits nonspecific antimicrobial activity relative to Mycobacterium tuberculosis , in contrast to known quaternary polymeric and low-molecular-weight biocides. The present paper is devoted to studying, using several physicochemical methods, the different facets of the interaction of secondary poly (diallylammonium trifluoroacetate) (PDAATFA) with Mycobacterium smegmatis – the nearest fast-growing relative of M. tuberculosis in comparison with the action of PDADMAC. We studied the interaction between polymer and phenolic glycolipids molecules (PGL) (i.e., molecules of the outer leaflet of both M. smegmatis and M. tuberculosis cell wall) by FTIR. We used phenyl-β-D-glucuronide as a model compound whose structure is close to that of the glycosylated phenolic part of the PGL molecule. It was assessed the polymer effect on transmembrane potential (TM) and permeability barrier of M. smegmatis . It was studied the biocidal activity of the polymers relative to M. smegmatis . The cytotoxic effect of PDAATFA on M. smegmatis cells was analyzed by TEM. We have proved the direct interaction of polymers with the outer membrane molecules for the first time. FTIR and the rest data show a formation of the non-covalent intermolecular hydrogen-bonded complex between protonated PDAATFA polymers and phenolic glycolipids that leads to the destruction of the mycobacterial outer membrane and, as a result, cell death. We believe that because of the structural similarity of cell wall chemistry and organization, this conclusion is proper for model organism M. smegmatis and pathogenic M. tuberculosis . Contrary to expected, the action of more hydrophobic PDADMAC does not lead to a destruction of the outer membrane but to a gradual suppression of the TM potential and cell death due to inhibition of general bioenergetic processes over the extended treatment time.

Timofeeva L., Lyashchenko A., Balakaeva I., Lileev A., Simonova Y.

The high-frequency dielectric relaxation of aqueous solutions of protonated diallylammonium polyelectrolyte, namely poly(diallylmethylammonium trifluoroacetate) has been studied at the maximum wate...

Simonova Y.A., Topchiy M.A., Filatova M.P., Yevlampieva N.P., Slyusarenko M.A., Bondarenko G.N., Asachenko A.F., Nechaev M.S., Timofeeva L.M.

We have studied applicability of reversible addition-fragmentation chain transfer/macromolecular design via the interchange of xanthate (RAFT/MADIX) method to radical cyclopolymerization of protonated diallylammonium monomer, namely diallylammonium trifluoroacetate (DAATFA), occurring with efficient chain transfer to monomer reaction. The latter drives to a significant extent polymerization, noticeably setting molecular weight, MW, of polymers and their polydispersity (polydispersity index (PDI) = 2.8–3.0). For the first time, upon DAATFA polymerization in presence of RAFT ethylxanthogenacetic acid (xanthate) in aqueous solutions at 70 °C, the side chain transfer reaction was inhibited and control of the polydispersity was achieved, the PDI = 1.2–1.3. The structural characteristic of poly(diallylammonium trifluoroacetate) (PDAATFA) polymers was analyzed via 1H and 13C NMR and IFS FTIR (ATR) spectroscopy. It was proved that the structure of polymers obtained by RAFT polymerization fully corresponds to the polymers PDAATFA containing cationic pyrrolidinium links and trifluoroacetate-counterions. At the optimal xanthate concentrations, the main products are polymers with the end dithiocarbonate group, i.e. macro-RAFT PDAATFA. Static/dynamic light scattering, viscometry and ultracentrifugation were used for polymers characterization. Molecular weight was determined by two independent methods: static light scattering (Mw) and hydrodynamic parameters analysis (MDη). The PDI Mw/Mn was calculated on the basis of Fujita approach, using the determined distributions of sedimentation coefficients. The experimental number average molecular weights, Mn, grow with polymerization time, 6700 g mol−1

Simonova Y.A., Filatova M.P., Timofeeva L.M.

The kinetics of the radical polymerization of protonated monomers of the diallylammonium series (diallyl- and diallylmethylammonium trifluoroacetates) in bidistilled aqueous solution (quartz bidistiller) is studied in situ using 1Н NMR spectroscopy. The rates of monomer consumption and polymer accumulation in the range of 30–50°С are determined. For diallylammonium trifluoroacetate, the effective activation energy of polymerization and the constant of chain transfer to the monomer (30°С) are estimated. It is found that the initial rates of polymerization are comparable with the rates of polymerization of quaternized analogs and the constant of chain transfer to the monomer and the activation energy of polymerization are close to the analogous characteristics of polymerization in the case of quaternized diallyldimethylammonium chloride. It is shown that for polymerization in bidistilled solution, the constant of chain transfer to the monomer (30°С, 3.8 × 10–3) is more than three times lower than that for polymerization in monodistillate (30°С, 12.2 × 10–3) and the ММ of the polymers is ~2.4 times higher than the ММ of the samples synthesized in monodistillate under the same conditions. It is ascertained that standard electrolyte admixtures in distilled aqueous solution considerably affect radical chemical reactions involving protonated forms.

Yevlampieva N., Vezo O., Simonova Y., Timofeeva L.

AbstractSecondary polyamine in protonated salt form – poly(diallylammonium trifluoro-acetate) is characterized as representative of polymer series based on N,N-diallyl-ammonium. Its hydrodynamic behavior in 1 M NaCl has been compared with the other series members – quaternary poly(diallyldimethylammonium chloride) and tertiary poly(diallylmethylammonium trifluoroacetate). It was shown that these polymers belong to semirigid class whose Kuhn segment length ∼4 nm just slightly depends on chemical structure at high ionic strength. As specific for secondary polyamine, the sensitivity to proton equilibrium in solution and counter ion type was detected resulting in great difference of its Mark–Kuhn–Houwink equations from the quaternary analogue at the same conditions.

Lyashchenko A.K., Balakaeva I.V., Simonova Y.A., Timofeeva L.M.

Results from microwave measurements of the dielectrical properties of aqueous pyrrolidinium trifluoroacetate solutions at maximum water dispersion frequencies (13–25 GHz) and temperatures of 288, 298, and 308 K are given. The static dielectrical constants, times, and activation parameters of the dielectrical relaxation of solutions are calculated. The enthalpy and time of dielectrical relaxation activation are increased by deceleration of the motion of water molecules in the hydrate shells of ions. The changes in dielectrical parameters are in this case minimal in a series of aqueous solutions of diallylammonium salts with cations of different structures and degrees of substitution. It is shown that pyrrolidinium ions are characterized by weak hydrophobic hydration.

Timofeeva L.M., Balakaeva I.V., Lileev A.S., Simonova Y.A., Lyashchenko A.K.

The specific and equivalent conductivity of the diluted aqueous solutions of diallyammonium polyelectrolytes, initial monomers (N,N-diallylammonium trifluoroacetate, N,N-diallyl-N-methylammonium trifluoroacetate, N,N-diallyl-N,N-dimethylammonium chloride), and also potassium trifluoroacetate and trifluoroacetic acid solutions are studied. The limiting ionic mobility of diallylammonium cations and trifluoroacetate anion are found. The regularities of concentration changes in the equivalent conductance of polyelectolytes solutions are established. The degree of dissociation of diallyammonium polymers is shown to depend both on the counterion nature and on the amine structure.

Timofeeva L.M., Kleshcheva N.A., Shleeva M.O., Filatova M.P., Simonova Y.A., Ermakov Y.A., Kaprelyants A.S.

Mycobacteria, especially Mycobacterium tuberculosis, are one of the most dangerous types of microorganisms to cause diseases and mortality. Due to the known distinctive structure of their cell wall, mycobacteria are resistant to majority of antibiotics and common chemical disinfectants, including quaternized low molecular weight and polymer biocides. In this work, nonquaternary protonated polydiallylamines (PDAAs) based on protonated monomers of the diallylamine (DAA) series have been synthesized, secondary s-PDAA and tertiary t-Me-PDAA and t-Et-PDAA (with Me and Et N-substituents). The antimicrobial actions of PDAAs on M. tuberculosis and Mycobacterium smegmatis have been studied, namely, dependences of the activity on the amine structure, length of alkyl N-substituents, M w of polymers, treatment time, and cell concentration. All PDAAs examined at different conditions have been found to exhibit strong bactericidal effect on M. smegmatis and M. tuberculosis, including “nonculturable” dormant M. tuberculosis cells. The quaternary counterpart poly(diallyldimethylammonium chloride) (PDADMAC) and current antibiotics rifampicin and ciprofloxacin have been also tested and shown to be significantly less efficient or inactive at all (at the maximum tested concentration of 500 μg mL−1). s-PDAA appeared to be the most effective or exhibited similar activity to t-Me-PDAA, while t-Et-PDAA appeared to be less active, especially against M. tuberculosis. The results obtained indicate a key role of the nonquaternary ammonium groups in the mycobactericidal action of PDAAs. Examination under an optical microscope in the epifluorescence mode has evidenced damage of the inner membrane permeability of M. smegmatis cells under the impact of PDAAs after 20 min. Studies on electrophoretic mobility (zeta-potential) of M. smegmatis cells and some model liposomes in the presence of PDAAs have revealed a small negative charge of mycobacteria outer surface and recharge in the presence of PDAAs. A conclusion was made that bactericidal activity of PDAAs is related to the disturbance of the integrity of the mycobacterial cell wall followed by damage of the inner membrane permeability.

Timofeeva L.M., Simonova Y.A., Eremenko I.V., Filatova M.P., Topchiy M.A., Kozobkova N.V., Shleeva M.O., Eropkin M.Y.

A series of antimicrobial protonated diallylammonium polymers, poly(diallylammonium trifluoroacetate) (PDAATFA), were synthesized by classical polymerization, using an especially elaborated method for preparation of polymers with low molecular weight (MW), and by RAFT polymerization, with different end groups in a range of MW values of (8–43) × 103 g∙mol−1. Cytotoxicity relative to eukaryotic cells (epithelioid lines A-549 and MA-104) and bactericidal activity of the polymers (relative to Pseudomonas aeruginosa and Staphylococcus aureus) are investigated. The effect of the end groups and MW on toxicity and bactericidal activity is shown. Dependence of the activity and, most of all, cytotoxicity on MW is preserved even at a small difference in MW values in the MW range of (18–40) × 103 g·mol−1. A clear dependence of the studied properties on the nature of the terminal group is revealed. Sulfate -O-S(=O)2-O¯ end group has a noticeable effect on the bactericidal efficiency and smaller influence on toxicity, while dithiocarbonyl end group -S-C(=S)-O-CH2-CH3 has a significant effect on efficiency and especially toxicity, drastically increasing the latter. Overall, based on the results obtained, polymers PDAATFA of low MW are considered promising antimicrobial agents for the creation of new transdermal drugs.

Fang R., Jin Y., Kong W., Wang H., Wang S., Li X., Xing J., Zhang Y., Yang X., Song N.

The rapid growth and spread of multi-drug resistance (MDR) in Tuberculosis (TB) poses a severe threat to global public health. Existing antibiotics are increasingly ineffective against MDR-TB, contributing to millions of deaths each year. Recently, novel antituberculosis nanomaterials have been developed as innovative tools to combat MDR-TB. This review introduces several nanotechnology-based strategies aimed at addressing drug resistance in TB infections. Specifically, we highlight key elements in two critical areas: (1) the construction of nanoparticles with inherent mechanisms to overcome drug resistance, for instance, the newly discovered antimicrobial peptides and metal ions can achieve 60%–99% clearance efficiency against TB strains. (2) The development of a series of nanocarriers to drug delivery efficiency and in vivo safety. Additionally, we also discuss the smart-designed nanomaterials that responsive to infectious microenvironment for locally and precisely deliver drug to infected sites. This review provides typical and comprehensive overview on the applications of nano-strategies for the treatment of drug-resistant TB-infections.

Eremenko I., Simonova Y., Filatova M., Yevlampieva N., Bondarenko G., Kleshcheva N., Timofeeva L.

Protonated diallylammonium polymers attract attention due to a number of properties, in particular high antimicrobial activity, including activity against the mycobacterium M. tuberculosis. To reduce the cytotoxic effect of polymers in the case of practical use, samples with a low MW are required. The work investigated the free radical polymerization of protonated diallylammonium monomers, diallylammonium trifluoroacetates, in excess of the initiator ammonium persulfate (10–1 M) and at average polymerization temperatures (40 and 50°C) to obtain polymers with a low degree of polymerization. It has been shown that under such conditions it is possible to obtain polymers with values suitable within the aim: 16000 < MW < 28000 g/mol. Using NMR and IR spectroscopy, it was shown that with an increase in the concentration of the initiator and, accordingly, a decrease in the molecular mass of polymers, the relative number of characteristic terminal vinyl groups decreases, and the terminal groups formed by the interaction of macroradicals with primary radicals of the initiator become predominant, in this case, sulphate groups of ammonium persulfate. The data obtained indicate that at high concentrations of the initiator, the characteristic reactions of chain transfer to the monomer are largely kinetically suppressed by the interactions of macroradicals with the primary radicals of the initiator. The approach used, which makes it possible to synthesize polymers with a low MW and terminal groups of the initiator, can be applicable in the future to vary the properties of antimicrobial activity and toxicity of polymers.

Patra S., Pareek D., Gupta P.S., Wasnik K., Singh G., Yadav D.D., Mastai Y., Paik P.

Yevlampieva N. ., Vezo O. ., Slyusarenko M. ., Gubarev A. ., Simonova Y. ., Eremenko I. ., Topchiy M. ., Timofeeva L. .

Protonated diallylammonium polymers are special among cationic polyelectrolytes, due to a series of properties including high antimicrobial activity, for example, towards Mycobacterium tuberculosis. The polymers samples should be characterized properly for their practical application. In this study, protonated secondary polydiallylamines based on diallylammonium trifluoroacetate have been synthesized via radical reversible addition−fragmentation chain-transfer polymerization in the presence of 2-[(ethoxycarbonothioyl)sulfanyl]acetic acid. The NMR spectroscopy data have shown that the macromolecules contain the dithiocarbonyl terminal groups enhancing the polymer solubility in nonaqueous media, for instance, in methanol. The obtained polymers have been investigated by means of hydrodynamics and dynamic light scattering methods; molecular mass and hydrodynamic parameters of the macromolecules have been determined. Comparison of the polymers with similar ones synthesized via conventional radical polymerization and bearing terminal vinyl groups has revealed the independence of their hydrodynamic properties in 1.0 mol/L NaCl on the synthesis method and the terminal groups structure at М > 8 × 103, thus allowing the application of the scaling relationships for the diallylammonium polymers to determine the molecular mass, irrespectively on the preparation methods.

Yevlampieva N.P., Vezo O.S., Slyusarenko M.A., Gubarev A.S., Simonova Y.A., Eremenko I.V., Topchiy M.A., Timofeeva L.M.

Protonated diallylammonium polymers are special among cationic polyelectrolytes, due to a series of properties including high antimicrobial activity, for example, towards Mycobacterium tuberculosis. The polymers samples should be characterized properly for their practical application. In this study, protonated secondary polydiallylamines based on diallylammonium trifluoroacetate have been synthesized via radical reversible addition−fragmentation chain-transfer polymerization in the presence of 2-[(ethoxycarbonothioyl)sulfanyl]acetic acid. The NMR spectroscopy data have shown that the macromolecules contain the dithiocarbonyl terminal groups enhancing the polymer solubility in nonaqueous media, for instance, in methanol. The obtained polymers have been investigated by means of hydrodynamics and dynamic light scattering methods; molecular mass and hydrodynamic parameters of the macromolecules have been determined. Comparison of the polymers with similar ones synthesized via conventional radical polymerization and bearing terminal vinyl groups has revealed the independence of their hydrodynamic properties in 1.0 mol/L NaCl on the synthesis method and the terminal groups structure at М 8 × 103, thus allowing the application of the scaling relationships for the diallylammonium polymers to determine the molecular mass, irrespectively on the preparation methods.

Jia X., Qian M., Peng W., Xu X., Zhang Y., Zhao X.

Utilizing the copolymerization modification of dimethyl diallyl ammonium chloride (DMDAAC), the high positive charge density of the copolymer could be maintained, thereby facilitating the deficiency of its monomer in the application. In this paper, poly (DMDAAC-co-DAMBAC) (9:1) was synthesized with an aqueous polymerization method using DMDAAC and methyl benzyl diallyl ammonium chloride (DAMBAC) as monomers and 2,2’-azobis [2-methylpropionamidine] dihydrochloride (V50) as an initiator. Targeted to the product’s weight-average relative molecular mass (Mw), the response surface methodology (RSM) was used to optimize the preparation process. The optimal process conditions were obtained as follows: w (M) = 80.0%, m (V50):m (M) = 0.00700%, m (Na4EDTA):m (M) = 0.00350%, T1 = 50.0 °C, T2 = 60.0 °C, and T3 = 72.5 °C. The intrinsic viscosity ([η]) of the product was 1.780 dL/g, and the corresponding double bond conversion (Conv.) was 90.25 %. Poly (DMDAAC-co-DAMBAC) (9:1) revealed a highest Mw of 5.637 × 105, together with the polydispersity index d (Mw/Mn) as 1.464. For the demulsification performance of simulated crude oil O/W emulsions, the demulsification rate of poly (DMDAAC-co-DAMBAC) (9:1) could reach 97.73%. Our study has illustrated that the copolymerization of DMDAAC and a small amount of DAMBAC with poor reactivity could significantly improve the relative molecular weight of the polymer, enhance its lipophilicity, and thus the application scope of the polymer.

Tamfu A.N., Kocak G., Ceylan O., Valentine F., Bütün V., Çiçek H.

Ali S.A., Al‐Muallem H.A., Mazumder M.A.

This article reviews the synthesis of polyzwitterions (PZs) (poly-carboxybetaines, -phosphonobetaines, and -sulfobetaines) having multiple pH-responsive centers. The synthesis follows the Butler cyclopolymerization protocol involving a multitude of diallylammonium salts and their copolymerization with SO2 and maleic acid. The PZs have been transformed into cationic-, anionic-polyelectrolytes, and polyampholytes under the influence of pH. Particular attention is given to the application of these polymers as antiscalants, mild steel corrosion inhibitors, components in constructing Aqueous Two-Phase Systems (ATPSs), and membrane modifiers. The ATPSs could be used to separate various biomolecules, including proteins. Many amphiphilic polymers incorporating a few mol % hydrophobic monomers have shown enhanced viscosities and could be suitable for applications in oil fields. The progress of applying Butler cyclopolymerization in reversible addition-fragmentation chain transfer (RAFT) chemistry has been discussed. Future works are expected to focus on RAFT cyclopolymerization to construct block copolymers.

Tikhonov A.M., Asadchikov V.E., Volkov Y.O., Roshchin B.S., Nuzhdin A.D., Makrinsky K.I., Ermakov Y.A.

The results of a systematic study on the adsorption of polylysine molecules of different lengths on the surface of a 1,2-dimyristoyl-sn-glycero-3-phospho-L-serine (DMPS) monolayer in the liquid (LE) and condensed (LC) states are presented. A compressibility diagram and the Volta potential were recorded with the Langmuir monolayer technique and further analyzed with the empirical approach. The structure of the monolayer films with adsorbed polypeptides was studied with synchrotron X-ray reflectometry. Two- and three-layer slab models describe the reflectivity data fairly well and reveal both the significant structural changes and the dehydration of the polar groups induced by all polylysines used at the maximal coverage of the monolayer interface in both the LE and LC states. On the one hand, in the LE phase of the monolayer (area per molecule A ≅ 70 Ǻ2), the integrated electron density of the lipid headgroup region is approximately half the density contained in the clean monolayer. This indicates both significant compaction and dehydration in the polar groups of the lipids, caused by the adsorption of polypeptides. On the other hand, in the LC state (A ≅ 40 Ǻ2), the degree of the hydration of the polar region is similar to that for the initial DMPS monolayer. However, both the electron density and the thickness of the head group region differ significantly from the values of these parameters for the clean monolayer in the LC state.

Duan X., Zhu X., Li G., Xia R., Qian J., Ge Q.

It is well acknowledged that the microphase-separated morphology of anion exchange membranes (AEMs) is of vital importance for membrane properties utilized in alkaline fuel cells. Herein, a rigid macromolecule poly(methyldiallylamine) (PMDA) is incorporated to regulate the microphase morphology of hyperbranched AEMs. As expected, the hyperbranched poly(vinylbenzyl chloride) (HB-PVBC) is guided to distribute along PMDA chains, and longer PMDA cha leads to a more distinct microphase morphology with interconnected ionic channels. Consequently, high chloride conductivity of 10.49 mS cm−1 at 30 °C and suppressed water swelling ratio lower than 30% at 80 °C are obtained. Furthermore, the β-H of pyrrolidinium cations in the non-antiperiplanar position increases the energy barrier of β-H elimination, leading to conformationally disfavored Hofmann elimination and increased alkaline stability. This strategy is anticipated to provide a feasible way for preparing hyperbranched AEMs with clear microphase morphology and good overall properties for alkaline fuel cells.

Kopiasz R.J., Zabost A., Myszka M., Kuźmińska A., Drężek K., Mierzejewska J., Tomaszewski W., Iwańska A., Augustynowicz-Kopeć E., Ciach T., Jańczewski D.

The spread of antibiotic-resistant pathogens and the resurgence of tuberculosis disease are major motivations to search for novel antimicrobial agents. Some promising candidates in this respect are cationic polymers, also known as synthetic mimics of antimicrobial peptides (SMAMPs), which act through the membrane-lytic mechanism. Development of resistance toward SMAMPs is less likely than toward currently employed antibiotics; however, further studies are needed to better understand their structure-activity relationship. The main objective of this work is to understand the cross-influence of hydrophobicity, main-chain flexibility, and the topology of ionenes (polycations containing a cationic moiety within the main-chain) on activity. To fulfill this goal, a library of ionenes was developed and compared with previously investigated molecules. The obtained compounds display promising activity against the model microorganisms and drug-resistance clinical isolates, including Mycobacterium tuberculosis. The killing efficiency was also investigated, and results confirm a strong effect of hydrophobicity, revealing higher activity for molecules possessing the flexible linker within the polymer main-chain.

Jia X., Zhang X., Peng W., Yang K., Xu X., Zhang Y., Wang G., Tao X.

Among nitrogen-containing cationic electrolytes, diallyl quaternary ammonium salt is a typical monomer with the highest positive charge density, which has attracted the most attention, especially in the research on homopolymers and copolymers of dimethyl diallyl ammonium chloride (DMDAAC), which occupy a very unique and important position. In order to improve the lipophilicity of substituted diallyl ammonium chloride monomers under the premise of high cationic charge density, the simplest, most direct, and most efficient structure design strategy was selected in this paper. Only one of the substituents on DMDAAC quaternary ammonium nitrogen was modified by alkyl; the substituents were propyl and amyl groups, and their corresponding monomers were methyl propyl diallyl ammonium chloride (MPDAAC) and methyl amyl diallyl ammonium chloride (MADAAC), respectively. The effect of substituent structure on the homopolymerization activity of methyl alkyl diallyl ammonium chloride was illustrated by quantum chemical calculation and homopolymerization rate determination experiments via ammonium persulfate (APS) as the initiator system. The results of quantum chemistry simulation showed that, with the finite increase in substituted alkyl chain length, the numerical values of the bond length and the charge distribution of methyl alkyl diallyl ammonium chloride monomer changed little, with the activation energy of the reactions in the following order: DMDAAC < MPDAAC < MADAAC. The polymerization activities measured by the dilatometer method were in the order DMDAAC > MPDAAC > MADAAC. The activation energies Ea of homopolymerization were 96.70 kJ/mol, 97.25 kJ/mol, and 100.23 kJ/mol, and the rate equation of homopolymerization of each monomer was obtained. After analyzing and comparing these results, it could be easily found that the electronic effect of substituent was not obvious, whereas the effect of the steric hindrance was dominant. The above studies have laid a good foundation for an understanding of the polymerization activity of methyl alkyl diallyl ammonium chloride monomers and the possibility of preparation and application of these polymers with high molecular weight.

Xue Y., Qiu Z., Zhao Z., Wang C., Cui R., Shen S., Zhao Y., Zhou S., Fang L., Chen Z., Zhu H., Zhu B.

With the rapid emergence of microbial infections induced by "superbugs", public health and the global economy are threatened by the lack of effective and biocompatible antibacterial agents. Herein, we systematically design a series of secondary ammonium-based hyperbranched poly(amidoamine) (SAHBP) with different alkyl chain lengths for probing high-efficacy antibacterial agents. SAHBP modified with alkyl tails at the hyperbranched core could efficiently kill Escherichia coli and Staphylococcus aureus, two types of clinically important bacteria worldwide. The best SAHBP with 12-carbon-long alkyl tails (SAHBP-12) also showed high activity against problematic multidrug-resistant bacteria, including Pseudomonas aeruginosa and methicillin-resistant S. aureus (MRSA). Based on ζ potential, isothermal titration microcalorimetry (ITC), and membrane integrity assays, it is found that SAHBP-12 could attach to the cell membrane via electrostatic adsorption and hydrophobic interactions, following which the integrity of the bacterial cell wall and the cell membrane is disrupted, resulting in severe cell membrane damage and the leakage of cytoplasmic contents, finally causing bacterial cell death. Impressively, benefiting from excellent membrane-active property, SAHBP-12 exhibited robust therapeutic efficacy in MRSA-infected mice wounds. Moreover, SAHBP-12 also showed excellent biosafety in vitro and in vivo, which undoubtedly distinguished it as a potent weapon in combating the growing threat of problematic multidrug-resistant bacterial infections.

Timofeeva L., Bondarenko G., Nikitushkin V., Simonova Y., Topchiy M., Eremenko I., Shleeva M., Mulyukin A., Kaprelyants A.

• Protonated polydiallylamines exhibit biocidal action on M. smegmatis. • It was proved direct interaction of polymers with the molecules of outer membrane. • Protonated polydiallylamines bind to phenolic glycolipids via non-covalent complex. • Hydrogen bonding gives the main contribution to the energy of complexation. • Rigid cell wall of M. smegmatis is vulnerable to protonated polydiallylamines. The protonated diallylammonium polymers (PDAA) are known to possess a high antimicrobial activity relative to a broad scope of pathogens, unlike their quaternary analog poly( N, N -diallyl- N, N -dimethylammonium chloride) (PDADMAC). Moreover, PDAA exhibits nonspecific antimicrobial activity relative to Mycobacterium tuberculosis , in contrast to known quaternary polymeric and low-molecular-weight biocides. The present paper is devoted to studying, using several physicochemical methods, the different facets of the interaction of secondary poly (diallylammonium trifluoroacetate) (PDAATFA) with Mycobacterium smegmatis – the nearest fast-growing relative of M. tuberculosis in comparison with the action of PDADMAC. We studied the interaction between polymer and phenolic glycolipids molecules (PGL) (i.e., molecules of the outer leaflet of both M. smegmatis and M. tuberculosis cell wall) by FTIR. We used phenyl-β-D-glucuronide as a model compound whose structure is close to that of the glycosylated phenolic part of the PGL molecule. It was assessed the polymer effect on transmembrane potential (TM) and permeability barrier of M. smegmatis . It was studied the biocidal activity of the polymers relative to M. smegmatis . The cytotoxic effect of PDAATFA on M. smegmatis cells was analyzed by TEM. We have proved the direct interaction of polymers with the outer membrane molecules for the first time. FTIR and the rest data show a formation of the non-covalent intermolecular hydrogen-bonded complex between protonated PDAATFA polymers and phenolic glycolipids that leads to the destruction of the mycobacterial outer membrane and, as a result, cell death. We believe that because of the structural similarity of cell wall chemistry and organization, this conclusion is proper for model organism M. smegmatis and pathogenic M. tuberculosis . Contrary to expected, the action of more hydrophobic PDADMAC does not lead to a destruction of the outer membrane but to a gradual suppression of the TM potential and cell death due to inhibition of general bioenergetic processes over the extended treatment time.

Eremenko I., Simonova Y., Filatova M., Yevlampieva N., Bondarenko G., Kleshcheva N., Timofeeva L.

Protonated diallylammonium polymers attract attention due to a number of properties, in particular high antimicrobial activity, including activity against the mycobacterium M. tuberculosis. To reduce the cytotoxic effect of polymers in the case of practical use, samples with a low MW are required. The work investigated the free radical polymerization of protonated diallylammonium monomers, diallylammonium trifluoroacetates, in excess of the initiator ammonium persulfate (10–1 M) and at average polymerization temperatures (40 and 50°C) to obtain polymers with a low degree of polymerization. It has been shown that under such conditions it is possible to obtain polymers with values suitable within the aim: 16000 < MW < 28000 g/mol. Using NMR and IR spectroscopy, it was shown that with an increase in the concentration of the initiator and, accordingly, a decrease in the molecular mass of polymers, the relative number of characteristic terminal vinyl groups decreases, and the terminal groups formed by the interaction of macroradicals with primary radicals of the initiator become predominant, in this case, sulphate groups of ammonium persulfate. The data obtained indicate that at high concentrations of the initiator, the characteristic reactions of chain transfer to the monomer are largely kinetically suppressed by the interactions of macroradicals with the primary radicals of the initiator. The approach used, which makes it possible to synthesize polymers with a low MW and terminal groups of the initiator, can be applicable in the future to vary the properties of antimicrobial activity and toxicity of polymers.

Sinelnikova D.G., Novoskoltseva O.A., Loiko N.G., Nikolaev Y.A., Yaroslavov A.A.

Negatively charged polycomplexes have been prepared by electrostatic complexation of synthetic cationic poly(diallyldimethylammonium chloride) with excess anionic sodium alginate. These polycomplexes exhibit pronounced antimicrobial activity due to the biodegradation of the alginate matrix and the release of the biocidal polycation. The results obtained are promising for the development of simultaneously attractive and toxic polymer constructs capable of destroying microorganisms.

Fay J.M., Kabanov A.V.

Timofeeva L., Bondarenko G., Nikitushkin V., Simonova Y., Topchiy M., Eremenko I., Shleeva M., Mulyukin A., Kaprelyants A.

• Protonated polydiallylamines exhibit biocidal action on M. smegmatis. • It was proved direct interaction of polymers with the molecules of outer membrane. • Protonated polydiallylamines bind to phenolic glycolipids via non-covalent complex. • Hydrogen bonding gives the main contribution to the energy of complexation. • Rigid cell wall of M. smegmatis is vulnerable to protonated polydiallylamines. The protonated diallylammonium polymers (PDAA) are known to possess a high antimicrobial activity relative to a broad scope of pathogens, unlike their quaternary analog poly( N, N -diallyl- N, N -dimethylammonium chloride) (PDADMAC). Moreover, PDAA exhibits nonspecific antimicrobial activity relative to Mycobacterium tuberculosis , in contrast to known quaternary polymeric and low-molecular-weight biocides. The present paper is devoted to studying, using several physicochemical methods, the different facets of the interaction of secondary poly (diallylammonium trifluoroacetate) (PDAATFA) with Mycobacterium smegmatis – the nearest fast-growing relative of M. tuberculosis in comparison with the action of PDADMAC. We studied the interaction between polymer and phenolic glycolipids molecules (PGL) (i.e., molecules of the outer leaflet of both M. smegmatis and M. tuberculosis cell wall) by FTIR. We used phenyl-β-D-glucuronide as a model compound whose structure is close to that of the glycosylated phenolic part of the PGL molecule. It was assessed the polymer effect on transmembrane potential (TM) and permeability barrier of M. smegmatis . It was studied the biocidal activity of the polymers relative to M. smegmatis . The cytotoxic effect of PDAATFA on M. smegmatis cells was analyzed by TEM. We have proved the direct interaction of polymers with the outer membrane molecules for the first time. FTIR and the rest data show a formation of the non-covalent intermolecular hydrogen-bonded complex between protonated PDAATFA polymers and phenolic glycolipids that leads to the destruction of the mycobacterial outer membrane and, as a result, cell death. We believe that because of the structural similarity of cell wall chemistry and organization, this conclusion is proper for model organism M. smegmatis and pathogenic M. tuberculosis . Contrary to expected, the action of more hydrophobic PDADMAC does not lead to a destruction of the outer membrane but to a gradual suppression of the TM potential and cell death due to inhibition of general bioenergetic processes over the extended treatment time.

Jung K., Corrigan N., Wong E.H., Boyer C.

Synthetic polymers are omnipresent in society as textiles and packaging materials, in construction and medicine, among many other important applications. Alternatively, natural polymers play a crucial role in sustaining life and allowing organisms to adapt to their environments by performing key biological functions such as molecular recognition and transmission of genetic information. In general, the synthetic and natural polymer worlds are completely separated due to the inability for synthetic polymers to perform specific biological functions; in some cases, synthetic polymers cause uncontrolled and unwanted biological responses. However, owing to the advancement of synthetic polymerization techniques in recent years, new synthetic polymers have emerged that provide specific biological functions such as targeted molecular recognition of peptides, or present antiviral, anticancer, and antimicrobial activities. In this review, the emergence of this generation of bioactive synthetic polymers and their bioapplications are summarized. Finally, the future opportunities in this area are discussed.

Li Petri G., Raimondi M.V., Spanò V., Holl R., Barraja P., Montalbano A.

The five-membered pyrrolidine ring is one of the nitrogen heterocycles used widely by medicinal chemists to obtain compounds for the treatment of human diseases. The great interest in this saturated scaffold is enhanced by (1) the possibility to efficiently explore the pharmacophore space due to sp3-hybridization, (2) the contribution to the stereochemistry of the molecule, (3) and the increased three-dimensional (3D) coverage due to the non-planarity of the ring—a phenomenon called “pseudorotation”. In this review, we report bioactive molecules with target selectivity characterized by the pyrrolidine ring and its derivatives, including pyrrolizines, pyrrolidine-2-one, pyrrolidine-2,5-diones and prolinol described in the literature from 2015 to date. After a comparison of the physicochemical parameters of pyrrolidine with the parent aromatic pyrrole and cyclopentane, we investigate the influence of steric factors on biological activity, also describing the structure–activity relationship (SAR) of the studied compounds. To aid the reader’s approach to reading the manuscript, we have planned the review on the basis of the synthetic strategies used: (1) ring construction from different cyclic or acyclic precursors, reporting the synthesis and the reaction conditions, or (2) functionalization of preformed pyrrolidine rings, e.g., proline derivatives. Since one of the most significant features of the pyrrolidine ring is the stereogenicity of carbons, we highlight how the different stereoisomers and the spatial orientation of substituents can lead to a different biological profile of drug candidates, due to the different binding mode to enantioselective proteins. We believe that this work can guide medicinal chemists to the best approach in the design of new pyrrolidine compounds with different biological profiles.

T J.A., J R., Rajan A., Shankar V.

An alternate host for mycobacteria is Mycobacterium smegmatis which is used frequently. It is a directly budding eco-friendly organism not emulated as human infection. It is mainly useful for the investigation of various microorganisms in the sort of Mycobacteria in cell culture laboratories. Some Mycobacterium species groups that is normal, unsafe ailments, likely to Mycobacterium leprae, Mycobacterium tuberculosis and Mycobacterium bovis. At present, various laboratories are clean and culture this type of species to make an opinion that fascinating route of harmful Mycobacteria. This publication provides aggregate data on cell shape, genome studies, ecology, pathology and utilization of M. smegmatis.

Kwon S., Yang W., Moon D., Kim K.S.

Lower cellular elasticity is a distinguishing feature of cancer cells compared with normal cells. To determine whether cellular elasticity differs based on cancer cell type, cells were selected from three different cancer types including breast, cervix, and lung. For each cancer type, one counterpart normal cell and three types of cancer cells were selected, and their elasticity was measured using atomic force microscopy (AFM). The elasticity of normal cells was in the order of MCF10A > WI-38 ≥ Ect1/E6E7 which corresponds to the counterpart normal breast, lung, and cervical cancer cells, respectively. All cancer cells exhibited lower elasticity than their counterpart normal cells. Compared with the counterpart normal cells, the difference in cellular elasticity was the greatest in cervical cancer cells, followed by lung and breast cancer cells. This result indicates lower elasticity is a unique property of cancer cells; however, the reduction in elasticity may depend on the histological origin of the cells. The F-actin cytoskeleton of cancer cells was different in structure and content from normal cells. The F-actin is mainly distributed at the periphery of cancer cells and its content was mostly lower than that seen in normal cells.

Kyzioł A., Khan W., Sebastian V., Kyzioł K.

Antimicrobial polymers (APs) are the new type of disinfectants, which can be used in some cases as an alternative to nowadays overused antibiotics. This review presents the most prognostic approaches in tackling infections and drug resistance with application of antimicrobial polymers. We describe membrane-active formulations composed of antimicrobial polymers with attention paid to drug delivery systems and selected methods of visualization of the antimicrobial effect. Importantly, antimicrobial polymers can not only be used independently but as well they can be tethered to surfaces without losing their biological activity. The latter approach enables the design of surfaces that (i) inactivate microbes even without releasing additional biocides or (ii) enhance antimicrobial activity of these biocides acting by additive or synergistic effect. One of the hallmarks of APs is their low susceptibility to the current and/or emerging resistance mechanisms. Simplicity of modulation of the antimicrobial activity by easy changes in their structures and the related optimization of biological potential make the formulations composed of antimicrobial polymers clinically relevant materials.

Nikitushkin V.D., Trenkamp S., Demina G.R., Shleeva M.O., Kaprelyants A.S.

Under gradual acidification of the culture medium mycobacterial cells transit into a specific state characterized by low level of metabolic activity and morphological alterations. This state of non-replicative persistence (dormancy) is directly linked to physiological drug resistance, which complicates the efforts to eradicate the latent forms of TB. In order to find new anti-latent TB compounds, the metabolic processes which may occur in the state of dormancy and during the transition into the active state (reactivation) should be characterized. In the current study we analyzed the untargeted metabolomic profiles of dormant and reactivating Mycolicibacterium smegmatis cells (a model microorganism, bearing many common physiological traits of MTB), on the global scale level, since the characterization and analysis of the metabolites’ dynamics would provide a comprehensive overview on global biochemical responses of the bacteria to stress conditions. The reactivation process was tracked by measuring the value of membrane potential, applying a ratio-metric approach, by the method of flow-cytometry. The crucial timepoints were selected and the bacteria were sampled to LC–MS metabolic profiling. Reactivation of these cells after 60 days of storage revealed that this process proceeds in two stages: (I) a period, which lasts for 10 h and is characterized by a constant CFU number, unchangeable cell size, a minuscule increase of respiratory activity and a noticeable increase in membrane potential value, indicating the onset of the first metabolic processes during this time interval; the second phase (10–26 h) is characterized by acceleration of endogenous respiration, changes in the size of the cells and it finishes with the beginning of cells division. Analysis of the changes in the relative abundances of KEGG-annotated metabolites revealed that a significant number of metabolites, such as stearic acid, glycerol, d-glucose, trehalose-6-phosphate decrease their concentrations over the reactivation time, whereas in contrast, such metabolites as dodecanoic acid, mycobactin S, and other compounds of PG/AG biosynthesis are synthesized during reactivation. Differential analysis of metabolic profiles disclosed the activation of a number of metabolic pathways at the early reactivation stage: biosynthesis of secondary metabolites, purine and pyrimidine metabolism, glycerophospholipid and fatty acids metabolism etc. The data obtained indicate, despite the long-term storage of dormant cells in a state of minimal metabolic activity, according to metabolic profiling, they still retained a large number of metabolites. In the process of reactivation, the incremental stochastic assembly of the complete metabolic pathways occurs.

Grube M., Cinar G., Schubert U.S., Nischang I.

The interrelation of experimental rotational and translational hydrodynamic friction data as a basis for the study of macromolecules in solution represents a useful attempt for the verification of hydrodynamic information. Such interrelation originates from the basic development of colloid and macromolecular science and has proven to be a powerful tool for the study of naturally- and synthetically-based, i.e., artificial, macromolecules. In this tutorial review, we introduce this very basic concept with a brief historical background, the governing physical principles, and guidelines for anyone making use of it. This is because very often data to determine such an interrelation are available and it only takes a set of simple equations for it to be established. We exemplify this with data collected over recent years, focused primarily on water-based macromolecular systems and with relevance for pharmaceutical applications. We conclude with future incentives and opportunities for verifying an advanced design and tailored properties of natural/synthetic macromolecular materials in a dispersed or dissolved manner, i.e., in solution. Particular importance for the here outlined concept emanates from the situation that the classical scaling relationships of Kuhn–Mark–Houwink–Sakurada, most frequently applied in macromolecular science, are fulfilled, once the hydrodynamic invariant and/or sedimentation parameter are established. However, the hydrodynamic invariant and sedimentation parameter concept do not require a series of molar masses for their establishment and can help in the verification of a sound estimation of molar mass values of macromolecules.

Krumm C., Trump S., Benski L., Wilken J., Oberhaus F., Köller M., Tiller J.C.

Biocidal compounds that quickly kill bacterial cells and are then deactivated in the surrounding without causing environmental problems are of great current interest. Here, we present new biodegradable antibacterial polymers based on polyionenes with inserted ester functions (PBI esters). The polymers are prepared by polycondensation reaction of 1,4-dibromobutene and different tertiary diaminodiesters. The resulting PBI esters are antibacterially active against a wide range of bacterial strains and were found to quickly kill these cells within 1 to 10 min. Because of hydrolysis of the ester groups, the PBI esters are degraded and deactivated in aqueous media. The degradation rate depends on the backbone structure and the pH. The structure of the polymers also controls the deactivation mechanism. While the more hydrophilic polymers require hydrolyses of only 19 to 30% of the ester groups to become practically inactive, the more hydrophobic PBI esters require up to 85% hydrolysis to achieve the same result. Thus, depending on the environmental conditions and the chemical nature, the PBI esters can be active for only 20 min or for at least one week.

Simonova Y.A., Topchiy M.A., Filatova M.P., Yevlampieva N.P., Slyusarenko M.A., Bondarenko G.N., Asachenko A.F., Nechaev M.S., Timofeeva L.M.

We have studied applicability of reversible addition-fragmentation chain transfer/macromolecular design via the interchange of xanthate (RAFT/MADIX) method to radical cyclopolymerization of protonated diallylammonium monomer, namely diallylammonium trifluoroacetate (DAATFA), occurring with efficient chain transfer to monomer reaction. The latter drives to a significant extent polymerization, noticeably setting molecular weight, MW, of polymers and their polydispersity (polydispersity index (PDI) = 2.8–3.0). For the first time, upon DAATFA polymerization in presence of RAFT ethylxanthogenacetic acid (xanthate) in aqueous solutions at 70 °C, the side chain transfer reaction was inhibited and control of the polydispersity was achieved, the PDI = 1.2–1.3. The structural characteristic of poly(diallylammonium trifluoroacetate) (PDAATFA) polymers was analyzed via 1H and 13C NMR and IFS FTIR (ATR) spectroscopy. It was proved that the structure of polymers obtained by RAFT polymerization fully corresponds to the polymers PDAATFA containing cationic pyrrolidinium links and trifluoroacetate-counterions. At the optimal xanthate concentrations, the main products are polymers with the end dithiocarbonate group, i.e. macro-RAFT PDAATFA. Static/dynamic light scattering, viscometry and ultracentrifugation were used for polymers characterization. Molecular weight was determined by two independent methods: static light scattering (Mw) and hydrodynamic parameters analysis (MDη). The PDI Mw/Mn was calculated on the basis of Fujita approach, using the determined distributions of sedimentation coefficients. The experimental number average molecular weights, Mn, grow with polymerization time, 6700 g mol−1

Kozon D., Mierzejewska J., Kobiela T., Grochowska A., Dudnyk K., Głogowska A., Sobiepanek A., Kuźmińska A., Ciach T., Augustynowicz‐Kopeć E., Jańczewski D.

Sasaki K., Popov I., Feldman Y.

It is not an understatement to say that the interplay between water and protein is a fundamental aspect of life. The vitality of an organism depends on the functionality of its biological machinery, and this, in turn, is mediated in water. Yet, we understand surprisingly little about the nature of the interface between bulk water and the protein. On the one hand, we know that the nature of the bulk water is dominated by the existence of H-bonding and H-bonded networks. On the other hand, the protein surface, where much of the bioactivity is centered, is a complex landscape of hydrophilic and hydrophobic elements. So how does the interface between these two entities work and how do they influence each other? The question is important because if one understands how a particular protein interface influences the dynamics of the water, it then becomes an easily accessible marker for similar behavior in other protein systems. The dielectric relaxation of hydrated proteins with different structures, lysozyme, collagen, and phycocyanin, has been reviewed in this paper. The dynamics of hydrated water was analyzed in terms of orientation and the ionic defect migration model. This approach enables to characterize the microscopic relaxation mechanism of the dynamics of hydration water on the different structures of the protein. In addition, our model is also capable of characterizing not only hydrated proteins but also polymer-water systems.