Innovative Nickel Foam Sorbent Enables Accurate Detection of Contaminants in Chinese Herbal Medicines

Chinese herbal medicines have long been cherished for their healing properties, but ensuring their safety is paramount. In a recent study published in Chromatographia, researchers from Jiangxi University of Chinese Medicine have introduced a breakthrough technique using a novel sorbent called diphenyl-functionalized nickel foam (NF-2Ph) for the accurate detection of polycyclic aromatic hydrocarbon (PAH) contaminants in Chinese herbal medicines (1).

Collection of raw Chinese herbal medicine as part of a classic herbal formula | Image Credit: © Tim Chow - stock.adobe.com

The researchers aimed to address the challenge of detecting PAH contaminants in Chinese herbal medicines, which can pose health risks if present at elevated levels. They synthesized a unique sorbent material, diphenyl-functionalized nickel foam (NF-2Ph), and evaluated its effectiveness in dispersive solid-phase extraction (DSPE) combined with gas chromatography–mass spectrometry (GC–MS) analysis.

To characterize the prepared sorbent, the researchers employed advanced analytical techniques, including scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometer (VSM), and N₂ adsorption-desorption experiments. These comprehensive analyses confirmed the structural and chemical properties of the diphenyl-functionalized nickel foam sorbent, highlighting its potential as an effective adsorbent material for the extraction of PAH contaminants.

Furthermore, the researchers explored key parameters that influenced the extraction process, such as sorbent dosage, extraction time, sample volume, desorption solvent type, eluent solvent volume, and elution time. Through meticulous optimization, the team achieved exceptional linearity (R² ≥ 0.9932) within the concentration range of 20–2000 ng mL^-1.

The proposed method exhibited remarkable sensitivity and accuracy, providing low limits of detection ranging from 0.5–7.6 ng mL^-1. It also demonstrated good precision with a relative standard deviation below 7.6% and satisfactory recoveries ranging from 83.0% to 110%. These findings validated the reliability of the diphenyl-functionalized nickel foam sorbent and its potential for PAH analysis in Chinese herbal medicines.

Importantly, the developed method was successfully applied to the simultaneous determination of 16 PAHs in Chinese herbal medicines. This practical application showcases the method's utility in ensuring the purity and safety of these medicinal products. By reliably detecting and quantifying PAH contaminants, this innovative approach can contribute to quality control in the Chinese herbal medicine industry and safeguard the health of individuals who rely on the therapeutic benefits of traditional herbal remedies.

The introduction of the diphenyl-functionalized nickel foam sorbent as a dispersive solid-phase extraction adsorbent represents a significant advancement in the field. With its reliable performance, sensitivity, and practical applicability, this method holds promise for enhancing the safety and quality assurance of Chinese herbal medicines. As the demand continues to grow, such advancements in analytical methodologies are crucial for maintaining consumer confidence and protecting public health.

Reference

(1) Li, Y.; Yan, Z.; Fan, J.; Yao, X.; Zhou, X.; Cai, Y. Application of Diphenyl Functionalization of Nickel Foam as Dispersive Solid-Phase Extraction Adsorbent to Polycyclic Aromatic Hydrocarbon Contaminants in Chinese Herbal Medicines. Chromatographia 2023. DOI: https://doi.org/10.1007/s10337-023-04264-1