Highly sensitive and selective colorimetric sensing of histidine by NAC functionalized AuNPs in aqueous medium with real sample application

•The NAC-AuNPs realized an extremely sensitive and highly selective sensing for His.•The assay is sensitive for His with a fast readout within 10 s and the LOD of 176 pM.•The assay exhibits the high selectivity of His sensing among 18 common amino acids.•The assay has been successfully applied in the spiked biological samples.