Mohamed, Aya M., Barton, Stephen J., Wren, Stephen P. and Barker, James (2022) Development of magnetic molecularly imprinted polymers for the extraction of salivary pepsin prior to analysis by a novel HPLC-SEC method. Polymer, 261, p. 125417. ISSN (print) 0032-3861
Abstract
Salivary pepsin is a very important and selective biomarker for gastroesophageal reflux disease and high concentrations in the saliva of potential patients can provide a very useful and non-invasive diagnostic tool. Therefore, this study focused on the development of new and highly selective magnetic molecularly imprinted polymers (MIPs) for the extraction of pepsin from human saliva samples. The developed MIPs provide a stable, cost-effective, and reusable synthetic method of extraction for pepsin. Surface imprinting technique was applied for the synthesis of MIPs to provide a wider surface area and faster binding/release of pepsin, since all the binding sites are allocated on the surface of iron oxide nanoparticles. Methacrylic acid was used as functional monomer, ethylene glycol dimethacrylate as cross linker, and deionized water as a porogen. The imprinting procedure was meticulously optimised to reach the highest possible binding indicated by the value of binding capacity Q which reached (190 mg g-1) and an imprinting factor of 1.34, calculated in comparison to non-imprinted polymers (NIPs). Moreover, the surface morphology, thermal stability as well as thebinding properties were characterised to ensure validity. The developed MIPs were applied successfully for dispersive solid phase extraction of pepsin from saliva samples. Consequently, a novel, highly sensitive and simple HPLC-SEC method was developed for the quantitation of pepsin fragments extracted using MIPs. The method was optimised and validated according to ICH guidelines where the linearity ranged from 5 to 150 μg mL-1 in saliva samples with LOD reaching down to 0.6 μg mL-1 which is comparable to the low concentrations of pepsin expected to be found in real saliva samples. The developed system enables the accurate extraction and determination of salivary with recoveries reaching to 98%. Therefore, this system shows potential as an efficient and reliable testing method for pepsin.
Actions (Repository Editors)
 |
Item Control Page |