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 96-well 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.

GRAPHICAL ABSTRACT

KEYWORDS:

• Levodopa
• magnetic nanoparticles
• pharmaceutical formulation
• magnetic microplate

Acknowledgements

This work was supported by the Ministry of Science and Technology, Taiwan (MOST) [grant number 105-2113-M-040-006].

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes on contributors

Hweiyan Tsai is a professor of Medical Applied Chemistry at Chung Shan Medical University, Taiwan. She received her PhD from University of Pittsburgh and worked as a postdoc research fellow at biomedical engineering department of Cleveland Clinic Foundation in USA and a project manager of Pharmaceutical Technology Development Programs at Industrial Technology Research Institute in Taiwan. Her major fields of research interest include electrochemical biosensors, magnetic functional nanoparticles for biochemical analyses and screening of functional foods.

Chia-Yi Chen received the B.S. degree from Medical Applied Chemistry at Chung Shan Medical University, Taiwan, in 2012. She is currently a student of master program at National Cheng Kang University, Taiwan.

Yi-Hsuan Lu received the B.S. degree from Medical Applied Chemistry at Chung Shan Medical University, Taiwan. She was a student of master program at National Chi Nan University, Taiwan and worked on the synthesis of nanoparticles.

Ya-Yun Lai received the Ph.D. degree from China medical University, Taiwan, in 2002. From 2003 to 2011, she was an assistant professor of Medical Applied Chemistry at Chung Shan Medical University, Taiwan. She is currently an associate professor in National Tainan Junior college of Nursing, Taiwan. Her research interests include synthesis and analysis of pharmaceutical compounds, evaluation of total flavonoids of herbs.

Chwan-Bor Fuh is a professor of Applied Chemistry at National Chi Nan University, Taiwan. He received his PhD from University of Utah and worked as a postdoc research fellow at biomedical engineering department of Cleveland Clinic Foundation in USA. He was a guesting professor at Osaka University in Japan. His major fields of research interest include thin channel, magnetic separation, and functional nanoparticles for analytical and biochemical analyses.

ORCID

Hweiyan Tsai http://orcid.org/0000-0002-4070-0058

Additional information

Funding

This work was supported by the Ministry of Science and Technology, Taiwan (MOST) [grant number 105-2113-M-040-006].