Porphyrin decorated CuO nanocrystals for electroanalytical detection of S-Nitrosothiols.

S-nitrosothiols (RSNO) as the potential nitric oxide (NO) storage, transfer and delivery vehicles under physiological condition have been identified as important in a number of disease states. However, a detection and quantification of RSNO method with simple and sensitive in biological media is currently lacking. A novel electrochemical sensing platform based on ionic liquid (IL) and copper porphyrin (PorCu) decorated cuprous oxide (CuO) nanocomposites was developed to detect RSNO under physiological condition. In this system, RSNO were decomposed by Cu(I) in IL/PorCu/CuO to release NO, following the generated NO could be oxidized on the electrode to generate current signal. By taking advantage of the synergetic effect of IL, PorCu and CuO, the sensor exhibited excellent sensitivity and linearity toward various RSNO species in phosphate buffer solution (PBS), pH 7.4. A low detection limit for N-Acetyl-3-(nitrososulfanyl)valine (SNAP), S-nitrosocysteine (CysNO) and S-nitrosoglutathione (GSNO) was 110 nM, 20 nM and 67 nM (S/N = 3), respectively. Furthermore, this method displayed good selectivity, which could be used in complex application. The detection scheme with the features of high sensitivity and ease of operation, implies the potential of IL/PorCu/CuO for further various complex physiological studies.