The cobalt sulphide nickel ternary material(NiCo2S4)prepared by hydrothermal method in this work was combined with multi-walled carbon nanotubes(MWCNT)for constructing an electrochemical sensor for quantitative detection of rutin.The morphology and crystal of the electrochemical materials were characterized by scanning electron microscopy and X-ray diffractometer,and the electrochemical behavior of the glassy carbon electrode(GCE)modified with NiCo2S4/MWCNT composites was investigated.The experimental results showed that the electrochemical redox process of two electrons and two protons occurred on the surface of modified electrode NiCo2S4/MWCNT/GCE.Under the optimized conditions,the linear range for detection of rutin by square-wave voltammetry(SWV)using this sensor was 0.06-14.8 μmol/L and the detection limit was 14.3 nmol/L.The electrochemical sensor was sensitive,simple and low-cost,with good reproducibility and reliable stability,and could be used for detection of rutin in real samples such as compound rutin tablets and color chrysanthemi tablets,with spiked recoveries of 99.5%-102.0%.

OBJECTIVETo investigate the status of bacterial contamination in the shellfish products in Wenzhou.

METHODSOne hundred samples were collected and their bacterial populations including the total plate count were investigated.

RESULTSOf the 100 samples collected, 67 samples failed to not meet the national regulations due to bacterial contamination, accounting for 67% of the total samples. Among the contaminated samples, the most serious contamination was caused by coliforms (61.4% of the total plate count with contamination), followed by Salmonella (18.6%), Vibio parahaemolyticus (15.7%), Listeria spp. (4.3%) and others (6%).

CONCLUSIONMicrobial pollution has become a threat to the marine shellfish products in Wenzhou.

Animals ; China ; Colony Count, Microbial ; Food Contamination ; Food Microbiology ; Listeria ; isolation & purification ; Salmonella ; isolation & purification ; Shellfish ; microbiology