Innovative Integration of Phase-Change Microcapsules with Metal–Organic Frameworks into an Intelligent Biosensing System for Enhancing Dopamine Detection

Abstract

This work focuses on an interdisciplinary issue in energy management and biosensing techniques. Aiming at enhancing the biosensing detection of dopamine at high ambient temperatures, we developed an innovative integration of phase-change microcapsules with a metal−organic framework (MOF) based on zeolitic imidazolate framework-8 to develop an intelligent electrochemical biosensing system with a thermal self-regulation function. We first fabricated a type of electroactive microcapsules containing a MOF-anchored polypyrrole/SiO 2 double-layered shell and a phase-change material (PCM) core. The resultant microcapsules not only exhibit a regular spherical morphology with a layer-by-layer core−shell microstructure but also display an effective temperature-regulation capability to enhance enzymatic bioactivity under phase-change enthalpies of around 124.0 J•g −1 along with good thermal impact resistance and excellent thermal cycling stability for long-term use in thermal energy management. These electroactive microcapsules were then used to modify a working electrode together with laccase as a biocatalyst to construct a thermal self-regulatory biosensor. With a high sensitivity of 3.541 μA•L•μmol −1 •cm −2 and a low detection limit of 0.0069 μmol•L −1 at 50 °C, this biosensor exhibits much better determination effectiveness toward dopamine at higher temperatures than conventional biosensors thanks to in situ thermal management derived from its PCM core in the electroactive microcapsules. This study offers a promising approach for development of intelligent thermal self-regulatory biosensors with an enhanced detection capability to identify various chemicals accurately in a wide range of applicable temperatures.

Recent Advances in Metal-Organic Framework-Based Electrochemical Biosensing Applications

“…A microcapsule comprising paraffin, SiO 2 , and polypyrrole (PPy) was anchored with ZIF-8 from the core to the outer layer. The PCM autonomously regulates heat to control the temperature around the biosensor in real time, thus weakening the dependence of the sensing process on environmental conditions ( Li et al, 2021b ).…”

A Comprehensive Review of Metal–Organic Framework: Synthesis, Characterization, and Investigation of Their Application in Electrochemical Biosensors for Biomedical Analysis

“…This biosensor shows better detection effectiveness for dopamine at higher temperatures. The biosensor also showed a linear range between 40.0 μM and 90.0 mM, and reflected higher sensitivity (3.541 μA L μmol −1 cm −2 ) with lower LOD of 0.0069 μM at 50 °C [ 106 ].…”

Microfluidic Production of Monodisperse Biopolymer Microcapsules for Latent Heat Storage

“…Microencapsulation of liquid oils has been performed by interfacial polymerization/polycondensation, − in situ polymerization, − suspension polymerization, − and emulsion polymerization. − Various types of shell materials have been used in these polymerization methods, including melamine-formaldehyde resin, ,, urea-formaldehyde resin, − polyurethane, , polystyrene, − and polyacrylates. ,− Another method for preparing microcapsules encapsulating PCMs is the phase separation method . In this method, a droplet containing a shell polymer, PCMs, and their solvent is first formed, and then, the solvent is evaporated to induce phase separation between the polymer-rich and PCM-rich phases in the droplet; finally, PCM-encapsulated polymer microcapsules are formed.…”