Modification of traditional composite nonwovens with stable storage of light absorption transients and photodynamic antibacterial effect.

Combining photodynamic antimicrobials with nonwovens is prospective. However, common photosensitizers still have drawbacks such as poor photoactivity and the inability to charge. In this study, a photodynamic and high-efficiency antimicrobial protective material was prepared by grafting bis benzophenone-structured 4,4-terephthaloyl diphthalic anhydride (TDPA) photosensitizer, and antimicrobial agent chlorogenic acid (CA) onto spunbond-meltblown-spunbond (SMS) membranes. The charging rates for ·OH and H2O2 were 6377.89 and 913.52 µg/g/h. The light absorption transients structural storage remained above 69% for 1 month. High electrical capacity remained after seven cycles indicating its rechargeability and recyclability. The SMS/TDPA/CA membrane has excellent bactericidal performance when under illumination or lightless conditions, and the bactericidal efficiency of Escherichia coli and Staphylococcus aureus reached over 99%. The construction of self-disinfection textiles based on the photodynamic strategies proposed in this paper is constructive for expanding and promoting the application of textile materials in the medical field.

Biomimetic helical fiber cellulose acetate/thermoplastic polyurethanes photodynamic antibacterial membrane: Synthesis, characterization, and antibacterial application.

This study designed a novel co-electrospun cellulose acetate (CA)/thermoplastic polyurethane (TPU) photodynamic helical fiber antibacterial membrane as a potential environmentally friendly medical protective material. A central combined design method (CCD) based on response surface methodology (RSM) was used to analyze essential variables' influence. The optimized parameters for CCD were TPU (wt%) 11.68 %, CA (wt%) 13.89 %, DMAc/ACE volume ratio 0.147, LiCl (wt%) 1.39 %, and voltage (kV) 14.43 V. Pitch and pitch diameter were the response process as the critical output variable. The membranes were characterized by SEM, TG, FT-IR, and molecular structure analysis. The results showed that the photodynamic helical fiber antimicrobial membrane exhibited synergistic effects of the antibacterial photodynamic therapy (APDT) and antimicrobial agent under average daylight irradiation. The release rate of -OH was 98.22 %, and H2O2 was 88.36 % under the action of 20 min of light. The bactericidal rates of S. aureus and E. coli reached 99.9 % and 99.7 %, respectively. The fiber helical structure can increase the light absorption rate, thus increasing the release rate and amount of reactive oxygen species (ROS) species, increasing the antibacterial rate. After washing five times, the antibacterial membrane has excellent antibacterial performance and a dark antibacterial effect.