Photoresponsive hydrogels have been attractive because they can provide precise spatial and temporal control for molecule release, whereas the conventional preparation of photoresponsive hydrogels generally involves c...Photoresponsive hydrogels have been attractive because they can provide precise spatial and temporal control for molecule release, whereas the conventional preparation of photoresponsive hydrogels generally involves complex chemical synthesis steps or specific conditions which limits their practical applications. Herein, a new photoresponsive hydrogel is facilely prepared via co-assembly of two simple molecules, Fmoc-Phe-OH and Azp, without chemical synthesis. The co-assembly mechanism, morphology, and photoresponsiveness of(Fmoc-Phe-OH)-Azp hydrogel are investigated by circular dichroism(CD), ultraviolet-visible(UV-Vis), fluorescence, ~1 H nuclear magnetic resonance(~1 H-NMR), attenuated total internal reflection Fourier transform Infrared(ATR-FTIR) spectroscopy, and scanning electron microscopy(SEM). Furthermore, the enhanced release of encapsulated sulforhodamine B(SRB) dye molecules can be achieved via UV light irradiation. The enhanced dye release amount can be controlled by manipulating photoirradiation time. This study provides a facile way to prepare photoresponsive hydrogel which holds great potential for controllable drug release.展开更多
One of the critical issues in gram-negative bacterial adhesion is how wettability regulates adhesion as the surface wettability varies from superhydrophilic to superhydrophobic,and what is the relevant/contributing ro...One of the critical issues in gram-negative bacterial adhesion is how wettability regulates adhesion as the surface wettability varies from superhydrophilic to superhydrophobic,and what is the relevant/contributing role of the lipopolysaccharide（LPS） outer layer of the gram-negative shell during this procedure.Herein,by avoiding the unexpected influence induced by the varied topographies,control over gram-negative bacteria adhesion by wettability is achieved on biomimetic hierarchical surfaces,which is mainly mediated by LPS layer.The study provides a methodology to have a good control over bacteria cell adhesion by properly designing wettable surface structures.This design concept is helpful for developing new generations of biomaterials in order to control a variety of diseases induced by gramnegative bacteria,which still continue to be very important and necessary in the fields of biomedicine.展开更多
基金financially supported by the Alexander von Humboldt Foundation(postdoc stipend to X.Q.Dou)the European Research Council(No.279202)the National Natural Science Foundation of China(Nos.51833006 and 51573092)
文摘Photoresponsive hydrogels have been attractive because they can provide precise spatial and temporal control for molecule release, whereas the conventional preparation of photoresponsive hydrogels generally involves complex chemical synthesis steps or specific conditions which limits their practical applications. Herein, a new photoresponsive hydrogel is facilely prepared via co-assembly of two simple molecules, Fmoc-Phe-OH and Azp, without chemical synthesis. The co-assembly mechanism, morphology, and photoresponsiveness of(Fmoc-Phe-OH)-Azp hydrogel are investigated by circular dichroism(CD), ultraviolet-visible(UV-Vis), fluorescence, ~1 H nuclear magnetic resonance(~1 H-NMR), attenuated total internal reflection Fourier transform Infrared(ATR-FTIR) spectroscopy, and scanning electron microscopy(SEM). Furthermore, the enhanced release of encapsulated sulforhodamine B(SRB) dye molecules can be achieved via UV light irradiation. The enhanced dye release amount can be controlled by manipulating photoirradiation time. This study provides a facile way to prepare photoresponsive hydrogel which holds great potential for controllable drug release.
基金the NSFC(Nos.51273111,51173105,51573092)the National Basic Research Program of China(973 Program,No.2012CB933803)SJTU-UM Collaborative Research Program,the Program for Professor of Special Appointment(Eastern Scholar)at the Shanghai Institutions of Higher Learning
文摘One of the critical issues in gram-negative bacterial adhesion is how wettability regulates adhesion as the surface wettability varies from superhydrophilic to superhydrophobic,and what is the relevant/contributing role of the lipopolysaccharide（LPS） outer layer of the gram-negative shell during this procedure.Herein,by avoiding the unexpected influence induced by the varied topographies,control over gram-negative bacteria adhesion by wettability is achieved on biomimetic hierarchical surfaces,which is mainly mediated by LPS layer.The study provides a methodology to have a good control over bacteria cell adhesion by properly designing wettable surface structures.This design concept is helpful for developing new generations of biomaterials in order to control a variety of diseases induced by gramnegative bacteria,which still continue to be very important and necessary in the fields of biomedicine.
