Sweeter but deadlier: decoupling size, charge and capping effects in carbohydrate coated bactericidal silver nanoparticles.
Silver nanoparticles are widely used due to their biomedical-antibacterial applications. At the same time, the stabilization of these nanoparticles is challenging and may be made using polymeric carbohydrates, based on the practice of avoiding toxic chemicals and undesirable residues. In this study, we synthesized silver nanoparticles (AgNPs) which were stabilized by carbohydrates (potato starch and chitosan) and characterized by UV-Vis spectroscopy, zeta potential and transmission electron microscopy techniques. Bactericidal efficiency of AgNPs capped with different carbohydrates was tested demonstrating that the synthesized materials were able to inhibit the growth of two clinical/medical relevant bacteria strains (Escherichia coil and Staphylococcus aureus). AgNPs stabilized by chitosan presented enhanced bactericidal activity if compared to the ones synthesized in presence of potato starch. This difference is mainly attributed to the known antibacterial properties of chitosan associated to overall positive charge of the nanoparticles capped by this polymer. Those nanoparticles obtained in presence of starch presented minor bactericidal effects since the starch-capping agent is not able to contribute to the avoidance of bacteria growth and confers a quasi-neutral charge to the nanoparticle.
LNLS-Laboratório Nacional de Luz Síncrotron, CEP 13083-970, Caixa Postal 6192, Campinas, SP, Brazil.
Luciane França
LF
de Oliveira
Julianna de Oliveira
Jde O
Gonçalves
Kaliandra de Almeida
Kde A
Gonçalves
Jörg
J
Kobarg
Mateus Borba
MB
Cardoso
D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000737:chemistry; D018407:Bacterial Physiological Phenomena / Q000187:drug effects*; D002241:Carbohydrates / Q000737:chemistry*; D002470:Cell Survival / Q000187:drug effects; D020099:Coated Materials, Biocompatible / Q000138:chemical synthesis; D008422:Materials Testing; D053768:Metal Nanoparticles / Q000008:administration & dosage* / Q000737:chemistry*; D053769:Nanocapsules / Q000008:administration & dosage* / Q000737:chemistry*; D012834:Silver / Q000008:administration & dosage* / Q000737:chemistry; D055672:Static Electricity
D000900:Anti-Bacterial Agents; D002241:Carbohydrates; D020099:Coated Materials, Biocompatible; D053769:Nanocapsules; D012834:Silver