Metal coordination induced SERS nanoprobe for sensitive and selective detection of histamine in serum

Sensitivity and credibility detecting histamine (HA) as an important neurotransmitter in biofluids is of importance in analytical science and physiology. Surface-enhanced Raman spectroscopy (SERS) is able to realize the high sensitivity with single molecules level, but providing the high sensitivity for HA with a small cross section remains a challenge. Here we develop the metal complex-based SERS nanoprobe nitrilotriacetic acid-Ni2+ (NTA-Ni2+) combined with self-assemble Au NPs active substrates for sensitive detection of HA. The NTA-Ni2+ can capture the HA molecules close to Au NPs substrates and then amplify the Raman signals of HA owing to the formation of a complex of NTA-Ni2+-HA. The self-assemble Au film through the evaporation-driven method can provide the high-density hot spots substrate with high stability and reproducibility. The NTA-Ni2+ decorated Au NPs as nanoprobe responds to HA with 1 μM level of sensitivity. More importantly, the developed SERS nanoprobe composing of NTA-Ni2+ and self-assemble Au NPs can be utilized to detect and monitor the HA spiked into serum, indicating the potential prospect in analysis of HA in complex specimen. [Display omitted] •Histamine has a strong affinity to Ni2+ through amino group and imidazole nitrogen.•The method of evaporation-driven assembly of Au NPs array with high density hot spots is facile and convenient.•NTA-Ni2+ functionalized Au NPs as SERS nanoprobe can realize sensitive and selective detection of HA.•Au NPs-NTA-Ni2+ SERS nanoprobe allows for efficiently analysis and record of HA in complex specimen. NTA-Ni2+ functionalized Au NPs as SERS nanoprobe not only can capture the histamine close to metallic nanostructure, but also can amply the Raman signals of histamine with high sensitivity.