Synthesis of gold nanoglycoconjugate towards Serratia marcescens and Pseudomonas aeruginosa, and their antimicrobial applications

Surface functionalized nanomaterials have outstanding potentials in biological applications owing to their target specific design. In this study, we utilized laboratory synthesized carbohydrate-derivatives (i.e. galactose, mannose, lactose and cellobiose derivatives) for aqueous one-pot synthesis of gold (Au) and silver (Ag) nanomaterial glycoconjugates (NPs), and iron metal organic framework glycoconjugates (FeMOFs). Even though the goal of the study was to evaluate antibacterial capacity of the AuNPs and corresponding antibiotic and amino acid modified ones using S.marcescens and P.aeruginosa. However, in order to make a comparison, AgNPs and FeMOFs synthesized with the sugar ligands were used, where such other gram (-) and gram (+) bacterial species were included to evaluate the selectivity. As of first step, Au_NPs, Ag_NPs and Fe_MOFs were tested against a variety of gram (-) and gram (+) bacterial strains, where Ag_NPs gave moderate to high antibacterial activities against all the tested bacterial strains while Au_NPs and Fe_MOFs showed their bacterial toxicity mostly depending on the strain. Minimum inhibitory concentration (MIC) and Minimum bactericidal concentration (MBC) tests were performed for the nanostructure glycoconjugates, where μg/mL MBC values were obtained. S.marcescens did not show any vulberability, as of MIC/MBC value, for the AuNPs under the tested highest concentrations (200 μg/mL) while it showed vulnerability towards L3AP_AgNP and L5AS_FeMOF/G5AS_FeMOFs. In conrast to this, P.aeruginosa gave 50 μg/mL MIC for G5AS_AuNPs while MIC/MBC values went down to 25 μg/mL for most of the AgNPs. Overall, the findings revealed that the nanostructure glycoconjugates can provide selective toxicity as antibacterial and anticancer agents.