Preparation and evaluation of antibacterial wound dressing based on vancomycin-loaded silk/dialdehyde starch nanoparticles

One of the main reasons infected wounds go untreated is that antibiotic-resistant bacteria mainly cause infection. Vancomycin is an antibiotic used against Gram-positive bacteria, such as MRSA, but it has limited intravenous use due to its toxicity. This study describes using a local drug delivery approach at the wound site. The aim is to prepare a silk dressing containing dialdehyde starch nanoparticles loaded with vancomycin that can cure infection through the controlled release of antibiotics. First, the starch was oxidized by sodium periodate solution and converted to dialdehyde starch. Dialdehyde starch was converted into nanoparticles by the microemulsion method. Simultaneously, with nanoparticle formation, the antibiotic vancomycin (VAN), added to the solution, was loaded into the dialdehyde starch nanoparticles (DASNP). The wound dressing (SF/DASNP/VAN) was prepared by adding nanoparticles containing antibiotics to the silk fibroin (SF) solution, and then, the solution containing the nanoparticles was freeze-dried, and the nanoparticles were placed inside the silk matrix. Drug release of dressings was performed by immersion in phosphate-buffered saline, and cytotoxicity by MTT assay and antibacterial properties of dressings were investigated by the inhibition zone method. The morphology of the SF/DASNP/VAN dressing, its biocompatibility, antibacterial efficiency, and antibiotic release kinetics were assessed. The synthesized dressing has the desired biocompatibility with 69% cell viability and shows antibacterial properties against MRSA with a growth inhibition zone diameter of 12 mm. Also, VAN was successfully incorporated into the dressing, resulting in a 144-h continuous release profile. It may be concluded that the fabricated dressing based on silk and dialdehyde starch nanoparticles opens up a new option for topical administration of antibiotics. We believe its properties can be considered a new dressing for infectious wounds by reducing infection associated with controlled drug delivery. Graphical abstract