It is of considerable concern to establish chiral detection methods for revealing enantioselective interactions among chiral molecules. Surfaceenhanced Raman scattering (SERS) spectroscopy is sensitive to molecular interaction due to bond variations. However, its application in chiral detection is underexplored. Inspired by the chiral selectivity toward glucose and amino acids in life, we herein propose a SERS strategy based on molecular interactions for the discrimination of D-and L-glucose (Glu) using chiral phenylalanine (Phe) decorated on gold nanoparticles as a chirality selector and Raman reporter. Interestingly, the SERS signal of L-Phe is enhanced by D-Glu but suppressed by L-Glu. In contrast, the SERS signal of D-Phe is increased by L-Glu but decreased by D-Glu. According to the above-observed intensity change (ΔI) of the SERS signal of Phe induced by Glu, it is easy to determine the chiral configurations (judged by the positive or negative sign of ΔI), enantiomeric excess (ee) values, and concentrations (estimated by the magnitude of ΔI) of Glu. Taking advantage of the high SERS enhancement and opposite enantiomeric effects on SERS signals, the proposed strategy enables enantiomeric discrimination at a low Glu concentration (10 −6 mol/L) and is further exerted for the noninvasive detection of D-/L-Glu in saliva samples. In contrast, the common chiroptical analysis tool of circular dichroism (CD) spectroscopy failed to directly detect Glu enantiomers.

The chirality of amino acids plays a key role in many biochemical processes, and the development of spectroscopic analysis methods for chiral differentiation of amino acids is significant. Normal Raman...

SERS spectroscopy, a nontraditional chiral analysis tool, is used to discriminate D- and L- phenylalanine (Phe), with the Raman scattering enhancement degree of D-Phe is 50-fold greater than L-Phe. Such...