Ag-Deposited Porous Silicon as a SERS-Active Substrate for the Sensitive Detection of Catecholamine Neurotransmitters

Abstract

The sensitive detection of various neurotransmitters is very useful in diagnosing diseases related to the dysfunction of the neurotransmitter system. Surface-enhanced Raman scattering (SERS) is one of the best methods for bio-analyte detection as it provides a molecular fingerprint at a trace concentration level. In this study, Ag-deposited porous silicon (Ag@pSi) was fabricated as a SERS-active substrate via metal-assisted chemical etching and electroless plating methods. Dopamine (DA) and norepinephrine (NE) neurotransmitters were tested as probing analytes. The Ag@pSi substrate demonstrated the sensitive detection of the neurotransmitters (DA and NE) over the wide concentration range (from 10(-6) to 10(-)(10) M), with a good linearity between the intensity of specific Raman peak and the log-scale concentration. The Ag@pSi substrate also distinguished the individual analytes in a mixture of DA and NE at 10(-8) M, confirming the efficacy of the developed SERS substrate for the selective detection of neurotransmitters. [GRAPHICS] .