In situ synthesis of ultrafine Cu2O on layered double hydroxide for electrochemical detection of S-nitrosothiols

Abstract

The identification and quantitation of S-nitrosothiols (RSNO) has aroused enormous levels of attention, due to RSNO have many roles in vivo. Here, we synthesized the nanocomposites of ultrafine Cu2O/layered double hydroxide (u-Cu2O/LDH) by the in situ topotactic reduction of a Cu2+-containing LDH with ascorbic acid under gentle conditions and applied these u-Cu2O/LDH to detect and monitor RSNO. Electrochemical signals of u-Cu2O/LDH exhibited a wide N-acetyl-S-nitrosopenicillamine detection range from 5.0 nM–4.0 μM and 4.0 μM–400 μM, with a low detection limit of 1.58 nM. The sensor also exhibited good performance for other RSNO, such as S-nitrosoglutathione, S-nitrosocysteine, and S-nitrosohomocysteine with corresponding limits of detection at 1.94 nM, 1.23 nM and 1.62 nM, respectively. The high levels of selectivity and sensitivity to RSNO in complex biological environments can be attributed to the abundance of exposed active sites, and the underlying support structure. In addition, u-Cu2O/LDH also exhibited dynamic nitric oxide (NO) monitoring ability from living cells. Collectively, these results reveal that u-Cu2O/LDH exhibit a remarkable ability to quantify RSNO levels in complex samples, and could therefore provide new tools for exploring ultrafine nanomaterials as a potential biosensor to investigate biological events.