Generic sensor platform based on electro-responsive molecularly imprinted polymer nanoparticles (e-NanoMIPs)

Abstract

The present research describes the design of robust electrochemical sensors based on electro-responsive molecularly imprinted polymer nanoparticles (e-MIPs). The e-MIPs, tagged with a redox probe, combine both recognition and reporting functions. This system replaces enzyme-mediator pairs used in traditional biosensors. The analyte recognition process relies on the generic actuation phenomenon when the polymer conformation of e-MIPs is changing in response to the presence of the template analyte. The analyte concentration is measured using voltammetric methods. In an exemplification of this technology, electrochemical sensors were developed for the determination of concentrations of trypsin, glucose, paracetamol, C4-homoserine lactone, and THC. The present technology allows for the possibility of producing generic, inexpensive, and robust disposable sensors for clinical, environmental, and forensic applications.

Keywords: Bionanoelectronics; Nanoparticles.

Fig. 1. Sensor principle and microscopy analysis.

a Schematic representation of the e-MIP response to the analyte; the analyte recognition triggered a detectable change in the polymer conformation. b SEM images of e-nanoMIPs for paracetamol detection

Fig. 2. Target molecules.

a THC, b C4-HSL, c trypsin, d paracetamol, and e glucose

Fig. 3. Glucose and C4-HSL sensor response and selectivity.

a Sensor response (DPV) of glucose e-MIPs to glucose; b Sensor response of glucose e-MIPs to (1) glucose (2) fructose (3) maltose and (4) lactose in a concentration range of 0.8–50 mM; c Sensor response (DPV) of C4-HSL e-MIPs to C4-HSL; d Sensor response of C4-HSL e-MIPs to (1) C4-HSL, (2) C6-HSL, (3) GBL, and (4) 3-oxo-C6-HSL in a concentration range 6.25–800 nM. All experiments were tested in PBS

Fig. 4. Paracetamol and THC sensor response and selectivity.

a Sensor response (DPV) of paracetamol e-MIPs to paracetamol; b Sensor response paracetamol e-MIPs to (1) paracetamol, (2) caffeine, (3) procainamide, and (4) ethyl 4-aminobenzoate in a concentration range 100–1000 µM. c Sensor response (DPV) of THC e-MIPs to THC; d Sensor response THC e-MIPs to (1) THC, (2) CBDV, (3) THC-COOH and (4) caffeine in a concentration range 0.1–1000 µM. All experiments were conducted in spiked plasma

Fig. 5. Trypsin sensor response and selectivity.

a Sensor response (DPV) of trypsin e-MIPs to trypsin; b Sensor response of trypsin e-MIPs to (1) trypsin, (2) avidin and (3) pepsin in a concentration range 6.5–100 nM. All experiments were conducted in spiked plasma