Bactericidal activity of starch-encapsulated gold nanoparticles
We report the bactericidal applications of ecofriendly starch encapsulated gold nanoparticles (StAuNPs). The mechanism of interaction of the properly characterized St-AuNPs with both Gram negative and Gram positive bacteria were investigated using spread plate assay, transmission electron microscopy (TEM), and fluorescent propidium iodide (PI) exclusion assay. The StAuNPs were found to possess significant dose dependent antibacterial activity against both types of bacteria. StAuNPs at 1.2 mg/mL caused 98 % eradication of Gram positive bacteria that was exposed over a period of 12 h. Similarly, 4.8 mg/mL St-AuNPs caused 98 % eradication of Gram negative bacteria over a period of 12h. The StAuNPs are biocompatible and present a useful solid porous carbohydrate-based polymer vehicle with excellent antimicrobial activity against both Gram negative and positive bacteria.