Green and efficient determination of ʟ-dopa in complex polypill formulations using a magnetic microplate

Abstract

A high-throughput and selective method for the determination of ʟ-dopa (levodopa) in complex formulations was developed. The method is based on the oxidation of ʟ-dopa to yield dopachrome using tyrosinase-labeled magnetic nanoparticles (TYR-MNPs) as the oxidation catalyst. TYR-MNP activity was retained at 75% after 20 reuse cycles, which is superior to previously reported systems that employ other substrates or cross-linkers for the immobilization of tyrosinase. In addition, the precision (< 3%), accuracy (recovery = 95-102%), and selectivity of the newly developed quantitative-analysis method for ʟ-dopa in complex polypill formulations meets the pharmaceutical industry's quality-control requirements; consequently this method can be applied to the routine analysis of complex formulations. The quality-control assay uses 96well microplates, which reduces the required volume of reagents, and the tyrosinase can easily be recycled and reused using an in-house-prepared magnetic microplate, thereby rendering the proposed method economical and less wasteful than existing methods.

Biosensor Strip for Rapid On‐site Assessment of Levodopa Pharmacokinetics along with Motor Performance in Parkinson's Disease

“…Several analytical methods, based on traditional labbased instruments, are used primarily in research settings to detect L-Dopa in biofluids, including high-performance liquid chromatography (HPLC) [13] and liquid chromatography-mass spectroscopy (LC-MS). [14,15] However, these assays are limited to centralized settings, and suffer from delayed turnaround times, resource-intensive requirements, limited accessibility, and high operating costs, and therefore cannot offer dynamic insights into rapidly changing L-Dopa concentrations. Such traditional approaches are thus impractical for providing timely clinical feedback on a proper L-Dopa dosing and are thus not suitable for personalized PD treatment.…”