Screen printed diamond electrode as efficient point-of-care platform for submicromolar determination of cytostatic drug in biological fluids and pharmaceutical product

This work presents advanced electrochemical platform based on screen printed diamond electrode (SPDE) system for the single drop point-of-care testing. Proposed approach was applied for the quantification of doxorubicin hydrochloride (DOX) in biological fluids and pharmaceutical product. Using a single drop (similar to 30 mu L) of the tested solution at the electrode surface, DOX showed high electroactivity over a wide range of pHs. In these conditions, single oval shaped, well-defined and pH dependent oxidation peak was observed in the potential range from 0.5 V to 1.3 V. In the reverse scan, two cathodic peaks, were noted - around 0.3 V and - 0.5 V. Similarly, first reduction peak was pH dependent, while second one was independent in the studied range. Experimental conditions for DOX quantification were optimized and natures of the electrode reactions were investigated. Working linear range obtained for DOX detection was from 0.1 to 2.5 mu M. Diffusion controlled electrode reaction reveal long life time of the proposed electrode as well high potential for practical application. Developed procedure was successfully applied for the DOX analysis in biological fluids - urine and pharmaceutical formulation. Obtained results clearly indicated that given procedure can be easily implemented for pharmaceutical control and medical analysis, in both, laboratory and field conditions.

Automated summary

This study introduces an advanced electrochemical platform based on screen printed diamond electrode system for single drop point-of-care testing, successfully applied for the quantification of doxorubicin hydrochloride in biological fluids and pharmaceutical products. The developed procedure can be easily implemented for pharmaceutical control and medical analysis in laboratory and field conditions.