Potential military cotton textiles composed of carbon quantum dots clustered from 4–(2,4–dichlorophenyl)–6–oxo–2–thioxohexahydropyrimidine–5–carbonitrile

This approach was applied to demonstrate a unique technique for manufacturing potential military textiles (fluorescent/UV-protective cotton fabrics with microbicide activity) through the immobilization of Carbon quantum dots (CQDs) within a textile matrix. Herein, CQDs were successfully nucleated from a pyrimidine-based heterocyclic compound, namely, 4–(2,4–dichlorophenyl)–6–oxo–2-thioxohexahydropyrimidine-5-carbonitrile, (Target molecule [TM]). Pyrimidine-based heterocyclic compounds have excellent pharmacological activities, but their photoluminescence activity has yet to be investigated. The synthesized TM and CQDs were separately immobilized within native and cationized cotton fabrics to obtain TM@cotton, CQDs@cotton, TM@Q-cotton, and CQDs@Q-cotton fabrics. The estimated yellowness index, intensity of the fluorescence peak, UV blocking, and microbicide action exhibited the following pattern: CQDs@Q–cotton > TM@Q–cotton > CQDs@cotton > TM @cotton. CQDs@Q-cotton showed quite good durability. After it was washed five times, its yellowness index decreased from 26.5–only 20.3, its fluorescence intensity decreased from 540–340 nm, and its transmission percent increased from 7–10%. Even after 10 washing cycles, microbial inhibitions (as a percent) against Escherichia coli, Staphylococcus aureus, and Candida albicans were estimated to be 63%, 68%, and 67%, respectively. The UV protection factor also decreased from 38.2 (very good)–21.5 (good). Therefore, the proposed technique was successfully used to manufacture durable fluorescent textiles that could be applied to superior military garments.