chondroitin-sulfates and melamine

Gold nanoparticles were green-synthesized using a glycosaminoglycan, chondroitin sulfate, as the reducing agent by mixing Au3+ and chondroitin sulfate under heating. Chondroitin sulfate-reduced gold nanoparticles were characterized by UV-Vis spectrophotometry, high resolution transmission electron microscopy and atomic force microscopy. The yield of Au3+ to Au0 was measured as 80.1% by inductively coupled plasma-atomic emission spectroscopy. A mostly spherical shape, with an average diameter of 44.68 +/- 11.25 nm, was observed from the atomic force microscopy images. Using chondroitin sulfate-reduced gold nanoparticles, we developed a melamine nanosensor that provides a simplified method to detect melamine in infant formula. With an increase in the melamine concentration in the gold nanoparticle solution, the characteristic surface plasmon resonance band of gold nanoparticles at 530 nm decreased, whereas a new peak appeared at 620 nm. There was a linear relationship between the absorbance ratio (A620/A530) and the melamine concentration in the range of 0.1-10 microM. The practical use of the proposed method was verified by quantifying melamine spiked in real infant formula at concentrations as low as 12.6 ppb. The nanosensing of melamine using chondroitin sulfate-reduced gold nanoparticles can be a promising technique for quick on-site melamine screening of milk products.

Topics: Chondroitin Sulfates; Gold; Humans; Infant; Infant Food; Limit of Detection; Metal Nanoparticles; Microscopy, Atomic Force; Microscopy, Electron, Transmission; Oxidation-Reduction; Spectrophotometry, Ultraviolet; Surface Plasmon Resonance; Triazines

Topics: Animal Feed; Animals; Cat Diseases; Cats; China; Chondroitin Sulfates; Dog Diseases; Dogs; Drug Contamination; Food Contamination; France; Fraud; Heparin; Humans; Infant; Milk; Milk Proteins; Poisoning; Public Health; Rats; Triazines