Enantioselective Target Transport-Mediated Nanozyme Decomposition for the Identification of Reducing Enantiomers in Asymmetric Nanochannel Arrays

Anal Chem. 2023 Sep 26;95(38):14465-14474. doi: 10.1021/acs.analchem.3c03089. Epub 2023 Sep 12.

Abstract

Enantioselective identification of chiral molecules is regarded as one of the key issues in biological and medical sciences because of their configuration-dependent effects on biological systems. In this study, we developed an electrochemical platform based on a tandem recognition-reaction zone design in TiO2 nanochannels for the specific recognition of reducing enantiomers. In this system, MIL-125(Ti) Ti-metal-organic frameworks, in situ grown in TiO2 nanochannels, provided a homochiral recognition environment via postmodification with l-tartaric acid (l-TA); MnO2 nanosheets possessing both glucose oxidase (GOD)- and peroxidase (POD)-mimicking activities served as the target-reactive zone at the end of the nanochannels. The use of penicillamine (Pen) enantiomers as model-reducing targets facilitated the passage of d-Pen through the homochiral recognition zone, owing to its lower affinity with l-TA. The passed Pen molecules reached the responsive zone and induced a target concentration-dependent MnO2 disassembly. Such target recognition event impaired the cascade GOD- and POD-like activities of MnO2. Combining the enantioselectivity of the recognition nanochannels with the cascade enzyme-like activity of MnO2 toward glucose and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate), the quantitative identification of l- and d-Pen was achieved through the changes in transmembrane ionic current induced by the generated charged products. This recognition-reaction zone design paves an effective way for developing a promising electrochemical platform for the identification of reducing enantiomers with improved selectivity and sensitivity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Glucose Oxidase
  • Manganese Compounds*
  • Oxides*
  • Penicillamine
  • Stereoisomerism

Substances

  • titanium dioxide
  • Manganese Compounds
  • Oxides
  • tartaric acid
  • Glucose Oxidase
  • Penicillamine