Recombinant single-chain variable fragment-based immunoassay for the authentication of Vietnamese ginseng via quantitative detection of majonoside R2

The scFv-based icELISA demonstrated a detection range of 31.25-1000 ng/mL for MR2, with high reproducibility and accuracy (CV <12.4 %, recovery 90.6 %-116.7 %). The assay was found to reliably distinguish authentic Ngoc Linh and Lai Chau ginsengs from other <i>Panax</i> species with high specificity. Recombinant expression in <i>E. coli</i> enables scalable, animal-free production, facilitating the broader adoption of this icELISA across laboratories equipped with standard molecular biology infrastructure. These findings support the integration of scFv-based assays into regulatory frameworks for authenticating Vietnamese ginseng.