Novel colorimetric sensor based on aggregation of noble metal nanomaterials for authenticity identification of Lycium ruthenicum from different regions

Lycium ruthenicum (Black goji berry, BGB) is a precious traditional Chinese medicine with numerous health benefits, highly sought after by consumers. However, its quality and price are greatly influenced by geographical location. Criminal adulterate such as inferior quality goji berries into genuine goji berries often occurs in the market, which results in huge economic losses. In this study, a novel method based on 3-aminobenzoic acid (PABA) modified gold nanoparticle clusters (PABA-AuNPs) was developed, utilizing noble metal nanomaterials combined with partial least squares discriminant analysis (PLS-DA) model for rapid and accurate identification of the origin of black goji berry. The recognition mechanism of this system was mainly due to the hydrogen bonding interaction between the –COO^- groups on the surface of PABA and the amino acid compounds in black goji berries. This approach exhibited enhanced sensitivity, specificity, and simplicity, achieving 100% accurate identification of black goji berry origin. The successful application of PABA-AuNPs colorimetric sensing in tracing the origin of black goji berry has laid the foundation for the rapid on-site identification of the origin of other food and medicinal materials.