ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Excellent laccase mimic activity of bimetallic Cu, Bi-PTs nanozyme sensor and its applications in quantification of morphine

Jinwen Zhao, Le Wang, Xiaolan Liu, Yanqin Zhu, and Qinhong Yin

Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming, China

E-mail: zyq23788@126.com

Received: 6 May 2025  Accepted: 8 November 2025

Abstract:

Nanozymes have been valuable tools in colorimetric analysis due to their ease of production, long-term stability, and adaptable enzymatic activity, enabling them to induce color changes in substrates. This study presents a straightforward enzyme-based colorimetric sensor for morphine (MOR) detection. The sensor utilized the laccase-like activity of a self-synthesized Cu, Bi-phosphotungstic acid (Cu, Bi-PTs) nanozyme, which was loaded with phosphotungstic acid, copper, and bismuth through a one-pot microwave method. This nanozyme was capable of catalyzing the coupling reaction of 2,4-dichlorophenol (2,4-DP) and 4-aminoantipyrine (4-AP), leading to the conversion of colorless phenolic compounds into red-colored products. The method demonstrated a detection limit of 1.88 μg/mL for MOR and a linear dynamic range from 3.333 to 400 μg/mL. The calibration curve, given by the equation y = 0.0015x + 0.4081, exhibited excellent linearity (R² = 0.9914), confirming the method's reliability for quantitative analysis. The developed colorimetric method was successfully applied to real samples, showing relative standard deviations (RSD) between 1.4 and 4.3% for MOR detection. These results demonstrated that the method was sensitive, cost-effective, and rapid, making it suitable for the efficient determination of MOR.

Keywords: Cu,Bi-PTs; Nanozyme; Laccase activity; Colorimetric detection; Morphine

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-025-04496-5

Chemical Papers 80 (2) 1881–1895 (2026)