A Highly Sensitive and Rapid Colloidal Gold Immunoassay for Puerarin Detection.

Radix Puerariae is a traditional Chinese medicinal material with a rich history of use in East and Southeast Asia. Puerarin, a unique component of the Pueraria genus, serves as a quality control marker for herbal medicines like Pueraria lobata and Pueraria thomsonii in China, displaying diverse pharmacological properties. This study developed puerarin colloidal gold immunoassay dipsticks utilizing an anti-puerarin monoclonal antibody, resulting in a fast and sensitive detection method with a limit of 500-1000 ng·mL-1. Evaluation using tap water-extracted P. lobata and P. thomsonii samples showed consistent results compared to LC-MS analysis. Cross-reactivity assessments of puerarin analogs revealed minimal interference, affirming the dipstick's reliability for distinguishing between the two species.

[Comparison of major chemical components in Puerariae Thomsonii Radix and Puerariae Lobatae Radix].

For further development and utilization of the germplasm resources of Puerariae Thomsonii Radix and Puerariae Lobatae Radix, this study developed the ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) method, high performance liquid chromatography(HPLC) method, and anthrone colorimetry to detect the content of 23 flavonoids, cellulose, hemicellulose, lignin, soluble sugar, and starch in Puerariae Thomsonii Radix and Puerariae Lobatae Radix. The content differences of various chemical components were analyzed. The methodological test of the established UPLC-MS/MS method for the determination of flavonoids showed that each component had satisfactory linearity within the corresponding linear range(R~2≥0.995), and the average spiked recoveries were 94.48%-105.5%. With this method, 17 flavonoids in Puerariae Lobatae Radix and Puerariae Thomsonii Radix were detected. Based on HPLC and anthrone colorimetry, the determination methods of lignocellulose, soluble sugar, and starch were established. According to the determination results, the content of cellulose in Puerariae Thomsonii Radix was significantly lower than that in Puerariae Lobatae Radix, and the content of starch was significantly higher than that in Puerariae Lobatae Radix. The content of hemicellulose, lignin, and soluble sugar showed no significant difference between the two medicinals, and the content of soluble sugar was in highly significantly negative correlation with that of starch. The established methods are simple, rapid, accurate, and sensitive. The results can lay a basis for the evaluation, and comprehensive development and utilization of the germplasm resources of Puerariae Thomsonii Radix and Puerariae Lobatae Radix.

[A monoclonal antibody-based icELISA for puerarin].

Puerarin was conjugated with bovine serum albumin(BSA) and ovalbumin(OVA) by periodate oxidation to serve as the immunogen and coating antigen, respectively. BALB/c mice were immunized with puerarin-BSA according to the routine immunization procedure, and the titer and specificity of serum were detected after three immunization. After booster immunization, mouse spleen lymphocytes were fused with mouse myeloma cells, and 24 hybridoma cell lines of the monoclonal antibodies against puerarin were screened by monoclonal antibody screening technique. Ascites was prepared and purified. The cross-reactivity of monoclonal antibody(mAb) M1 with 4'-methoxy puerarin, daidzin, puerarin-6″-O-xyloside, daidzein, mirificin, 3'-methoxy puerarin, and 3'-hydroxy puerarin was 239.84%, 112.18%, 67.89%, 58.28%, 22.37%, 0.40%, and 0.20%, respectively, and those with other analogs such as baicalein and baicalin were all less than 0.10%. The IC_(50) and the working range of the indirect competitive enzyme-linked immunosorbent assay(icELISA) for puerarin were 44.80 ng·mL~(-1) and 8.20-292.30 ng·mL~(-1), respectively. The average recovery was 91.95%-98.20% with an RSD in the range of 0.70%-2.60%. The content of puerarin in different Puerariae Lobatae Radix samples was determined with icELISA and validated by UPLC-MS. The correlation between data obtained from icELISA and UPLC-MS was 0.999 0, indicating that icELISA is suitable for the rapid detection of puerarin in Puerariae Lobatae Radix samples.

Rapid and intelligent discrimination of Notopterygium incisum and Notopterygium franchetii by infrared spectroscopic fingerprints and electronic olfactory fingerprints.

This preliminary research evaluated mid-infrared (MIR) spectroscopy, near-infrared (NIR) spectroscopy and electronic nose (E-nose) for the rapid identification of Notopterygium incisum and Notopterygium franchetii, which were both approved sources of Notopterygii Rhizoma et Radix (Chinese Pharmacopoeia, 2015) but possessed different chemical compositions and pharmacological activities. At the level of single variables, MIR showed quite a few discriminating peaks in the regions of 3000-2800 cm-1 (the stretching bands of CH), 1770-1670 cm-1 (the stretching bands of CO), and 1400-1200 cm-1 (the bending bands of CH and the stretching bands of CO). Meanwhile, NIR only showed an intuitive discriminating peak near 4736 cm-1 (the combination band of OH and CO stretching modes). E-nose response signals of N. incisum and N. franchetii were significant different (p < 0.05) on four sensors, i.e., LY2/LG, LY2/GH, LY2/gCT and LY2/gCTI. Using the infrared spectra or E-nose sensor responses as fingerprints, support vector machine (SVM) models can provide good recognition accuracy (100% for MIR and NIR models, 92.9% for E-nose model). This research indicated the feasibility of MIR, NIR and E-nose for the accurate, rapid, cheap and green identification of N. incisum and N. franchetii, which was desirable to assure the authenticity, efficacy and safety of related herb materials and products.