World Congress on
Advances in Analytical and Bioanalytical Techniques

Biography:

Abstract:

The work demonstrates the use of carbohydrate-conjugated nanomaterial (glyconanomaterial) to target bacterial pathogens. A collection of systematic studies done by several groups has demonstrated that bacteria can be specifically targeted using various oligosaccharides. Through our preliminary investigations we have discovered that oligosaccharide conjugated nanoparticles (glyconanoparticles) could be used to target strain specific bacteria. For example D-maltoheptaose (G7) and trehalose conjugated nanoparticle used to effectively target Escherichia coli and Mycobacterium spp. Antibiotic resistance in pathogenic bacterial strains is a growing global concern. We have demonstrated that these glyconanoparticles have been used as a carrier for antibiotics that would help target bacteria and reduce minimum inhibitory concentration of a conventional antibiotic. Antibiotic streptomycin (Str) is a broad range aminoglycoside typically used in the treatment of tuberculosis. We have bi-functionalized a nanoparticle using carbohydrate-G7 antibiotic-Str to produce glyconanoantibiotics (GNAs). As proof of concept for active targeting GNAs are used against a highly Str resistant E. coli strain. The GNAs demonstrated size dependent increased antibacterial efficacy few log folds improvement over the free the free antibiotic (Str).

Biography:

Abstract:

To develop a new strategy for inflamed site-specific drug delivery in the colon for the treatment of ulcerative colitis (UC), we focused on the interaction between myeloperoxidase (MPO) and human serum albumin (HSA) and prepared nanoparticles (HSA NPs) conjugated with 5-aminosalicylic acid (5-ASA), an anti-inflammatory drug. The 5-ASA-HSA NPs (nine molecules of 5-ASA per HSA molecule) were uniform particles with an average particle size of 190 nm, a zeta potential of -11.8 mV, and a polydispersity index of 0.35. This was considered a suitable particle characteristic to pass through the mucus layer and accumulate into the mucosa. The specific interaction between the 5-ASA-HSA NPs and MPO was observed using quartz crystal microbalance analysis in vitro. In addition, the 5-ASA-HSA NPs group containing one thousandth of the dose of the 5-ASA (75 μg/kg) showed significantly lower disease activity index values and colon weight/length ratios in UC model mice as similar to large amount of neat 5-ASA group (75 mg/kg), indicating that the therapeutic effect of the 5-ASA-HSA NP formulation was confirmed in vivo. Microscopic images of tissue sections of colon extracted from UC model mice demonstrated that HSA NPs and MPO were both localized in the colon, and this specific interaction between HSA NPs and MPO would be involved the in the therapeutic effect in vivo. Furthermore, in the 5-ASA and 5-ASA-HSA NPs groups, some inflammatory damage was observed in the colon, but the degree of damage was mild compared with the control and HSA NPs groups, suggesting mucosal repair and replacement with fibrous granulation tissue had occurred. Therefore, these data demonstrated for the first time, that an HSA NP formulation has the potential to specifically deliver 5-ASA to an inflamed site where MPO is highly expressed.