We report herein the development of a highly sensitive and selective colorimetric detection method for cysteine using gold nanoparticles probes. This assay relies upon the distance-dependent optical properties of gold nanoparticles, the self-assembly of cysteine on gold nanoparticles, and the interaction of a 2:1 cysteine/Cu2+ complex. In the presence of Cu2+, cysteine could rapidly induce the ...

We have built a high-resolution differential surface plasmon resonance (SPR) sensor for heavy metal ion detection. The sensor surface is divided into a reference and sensing areas, and the difference in the SPR angles from the two areas is detected with a quadrant cell photodetector as a differential signal. In the presence of metal ions, the differential signal changes due to specific binding ...

A PVC membrane Cr(III) ion selective electrode has been constructed using 2H-1,4-benzothioazine-2,3(4H)dione dioxime (BTD) as membrane carrier. The influence of membrane composition on the electroderesponse was studied. The electrode exhibits a Nernstian response over a Cr(III) concentration range of 1.0 x10 6 to 1.0>< 10-1 M (r = 0.99) with a slope of 19.5 ± 0.5 mV per decade of concentration,...

Copper efflux oxidases (CueOs) are key enzymes in copper homeostasis systems. The mechanisms involved however largely unknown. CueO-type share a typical structural feature composed of Methionine-rich (Met-rich) domains that proposed to be homeostasis. Bioelectrocatalysis using the presence Cu2+ recently highlighted new Cu2+-dependent catalytic pathway related cuprous oxidase activity. In this w...