RESUMO
The management of multibacterial infections remains clinically challenging in the care and treatment of chronic diabetic wounds. Photodynamic therapy (PDT) offers a promising approach to addressing bacterial infections. However, the limited target specificity and internalization properties of traditional photosensitizers (PSs) toward Gram-negative bacteria pose significant challenges to their antibacterial efficacy. In this study, we designed an iron heme-mimetic PS (MnO2@Fe-TCPP(Zn)) based on the iron dependence of bacteria that can be assimilated by bacteria and retained in different bacteria strains (Escherichia coli, Staphylococcus aureus, and methicillin-resistant Staphylococcus aureus) and which shows high PDT antibacterial efficacy. For accelerated wound healing after antibacterial treatment, MnO2@Fe-TCPP(Zn) was loaded into a zwitterionic hydrogel with biocompatibility and antifouling properties to form a nanocomposite antibacterial hydrogel (PSB-MnO2@Fe-TCPP(Zn)). In the multibacterial infectious diabetic mouse wound model, the PSB-MnO2@Fe-TCPP(Zn) hydrogel dressing rapidly promoted skin regeneration by effectively inhibiting bacterial infections, eliminating inflammation, and promoting angiogenesis. This study provides an avenue for developing broad-spectrum antibacterial nanomaterials for combating the antibiotic resistance crisis and promoting the healing of complex bacterially infected wounds.
Assuntos
Antibacterianos , Materiais Biocompatíveis , Testes de Sensibilidade Microbiana , Fotoquimioterapia , Fármacos Fotossensibilizantes , Cicatrização , Cicatrização/efeitos dos fármacos , Animais , Camundongos , Antibacterianos/farmacologia , Antibacterianos/química , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Heme/química , Teste de Materiais , Ferro/química , Escherichia coli/efeitos dos fármacos , Tamanho da Partícula , Diabetes Mellitus Experimental/tratamento farmacológico , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Compostos de Manganês/química , Compostos de Manganês/farmacologiaRESUMO
Al-La hybrid gel was constructed using an innovative acid-catalyzed and calcination free sol-gel formation process which only included a sol-gel process lasting for 30 min and a drying procedure at 150 °C. This novel material was used as an adsorbent for competitive adsorption of fluoride ions in zinc sulfate solution. The properties, optimal adsorption conditions, synthetic principle and adsorption mechanism of the material were systemically investigated. The results showed that γ-AlO(OH) composed the skeleton of the Al-La hybrid gel and La(CH3COO)3 was embedded in the framework, which formed large amounts of ink-bottle type mesopores. A high fluoride ion adsorption rate with the removal rate reaching 50.88% within 1 min at 50 °C, 3 g L-1 was obtained. Analysis of the adsorption data has demonstrated that the adsorption of fluoride ions by the Al-La hybrid gel followed pseudo-second-order kinetics. Moreover, both Langmuir and Freundlich models can describe the adsorption process well. The maximum adsorption capacity of the Al-La hybrid adsorbent was 28.383 mg g-1. Furthermore, the mechanism analysis results indicated that the fluoride ions were mainly removed by the electrostatic adsorption on the AlO(OH), and a small amount of fluoride ions was also adsorbed by the complexation of lanthanum and fluoride ions. Since both AlO(OH) and La(CH3COO)3 had a large number of fluoride ion adsorption sites, the Al-La hybrid gel obtained an ideal adsorption capacity. In addition, the adsorption rate was greatly enhanced by the capillary action existing from the initial to the final stage of adsorption.
