title: Preparation, characterization and evaluation of a biopolymeric gold nanocomposite with antimicrobial activity.
abstract: The present study describes the antimicrobial activity of C-AuNp-Amp (chitosan-capped gold nanoparticles coupled with ampicillin). C-AuNp-Amp was synthesized using the wet precipitation method and characterized using FTIR (Fourier-transform IR) spectroscopy and AFM (atomic force microscopy) techniques. The optimal level of ampicillin concentration that couples with the C-AuNp nanocomposite was determined by using UV-visible spectroscopy. The agar-well diffusion method was used to evaluate the antimicrobial activity, and the broth dilution assay was used to determine the MIC (minimum inhibitory concentration). The size of the ellipsoidal C-AuNp-Amp particles was found to be in the range of 50-100 nm. The FTIR spectrum confirms the bonding between amino groups of chitosan and carboxylic groups of ampicillin. The maximum coupling of ampicillin with C-AuNp was found to be 4.07 mg/10 ml. These results revealed the antimicrobial efficacy of C-AuNp-Amp and a 2-fold increase in activity was achieved when compared with that of free ampicillin. By reducing the antibiotic dosage to 50%, the side effects produced by antibiotics can be minimized.
authors.affiliation: St. Joseph's College of Engineering, Sholinganallur, Chennai 600 119, India.
authors.forename: Munusamy
authors.initials: M
authors.lastname: Chamundeeswari
authors.forename: S S Liji
authors.initials: SS
authors.lastname: Sobhana
authors.forename: Justin P
authors.initials: JP
authors.lastname: Jacob
authors.forename: M Ganesh
authors.initials: MG
authors.lastname: Kumar
authors.forename: M Pandima
authors.initials: MP
authors.lastname: Devi
authors.forename: Thotapalli P
authors.initials: TP
authors.lastname: Sastry
authors.forename: Asit B
authors.initials: AB
authors.lastname: Mandal
mesh_terms: D000667:Ampicillin / Q000008:administration & dosage* / Q000494:pharmacology*; D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000494:pharmacology*; D048271:Chitosan / Q000737:chemistry*; D004337:Drug Carriers / Q000737:chemistry; D004926:Escherichia coli / Q000187:drug effects; D006046:Gold / Q000737:chemistry*; D008826:Microbial Sensitivity Tests; D018625:Microscopy, Atomic Force; D015394:Molecular Structure; D053761:Nanocomposites / Q000737:chemistry*; D013053:Spectrophotometry; D017550:Spectroscopy, Fourier Transform Infrared; D013211:Staphylococcus aureus / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D004337:Drug Carriers; D006046:Gold; D000667:Ampicillin; D048271:Chitosan