Impedimetric Sensors for Cyclocreatine Phosphate Determination in Plasma Based on Electropolymerized Poly(o-phenylenediamine) Molecularly Imprinted Polymers

Abstract

Cyclocreatine and its water-soluble derivative, cyclocreatine phosphate (CCrP), are potent cardioprotective drugs. Based on recent animal studies, CCrP, FDA-awarded Orphan Drug Designation, has a promising role in increasing the success rate of patients undergoing heart transplantation surgery by preserving donor hearts during transportation and improving the recovery of transplanted hearts in recipient patients. In addition, CCrP is under investigation as a promising treatment for creatine transporter deficiency, an X-linked inborn error resulting in a poor quality of life for both the patients and the caregiver. A newly designed molecularly imprinted polymer (MIP) material was fabricated by the anodic electropolymerization of o-phenylenediamine on screen-printed carbon electrodes and was successfully applied as an impedimetric sensor for CCrP determination to dramatically reduce the analysis time during both the clinical trial phases and drug development process. To enhance the overall performance of the proposed sensor, studies were performed to optimize the electropolymerization conditions, incubation time, and pH of the background electrolyte. Scanning electron microscopy, electrochemical impedance spectroscopy, and cyclic voltammetry were used to characterize the behavior of the developed ultrathin MIP membrane. The CCrP-imprinted polymer has a high recognition affinity for the template molecule because of the formation of 3D complementary cavities within the polymer. The developed MIP impedimetric sensor had good linearity, repeatability, reproducibility, and stability within the linear concentration range of 1 × 10–9 to 1 × 10–7 mol/L, with a low limit of detection down to 2.47 × 10–10 mol/L. To verify the applicability of the proposed sensor, it was used to quantify CCrP in spiked plasma samples.

Determination of aflatoxin B1 by biomass derived porous carbon modified electrode with molecularly imprinted polymer

“…Considering the very low solubility of aflatoxin B 1 in aqueous solution, the monomer to template molar ratio used here is 1 mM phenol to 250 nM aflatoxin B 1 , which is 4000 : 1. The monomer/template molar ratio of other molecules sensing MIPs is found to be 4 : 1 [15], 1 : 1 [16] and 10 : 1 [17], which is much smaller than this study ratio of 4000 : 1. Therefore, the template cavities in the phenol MIP matrix is much less, which could result a small signal response and restrict the MIP sensor sensing range.…”

Electrochemical sensing of macromolecules based on molecularly imprinted polymers: challenges, successful strategies, and opportunities

“…Although such approaches have been widely used in macromolecule MIP-based electrochemical detection, it is worth highlighting that particular attention should be paid when developing MIPs with polymeric materials prone to such shrinking/swelling phenomena, as modifications of detected current signals merely imputable to polymer permeability could be erroneously interpreted as due to the target binding process. This could occur particularly with polymers that are well known for their permeability properties, such as poly(phenylenediamine) (PPD) [ 183 ], which is widely used in the synthesis of MIPs exploiting such gate effect for electrochemical sensing [ 124 , 184 – 186 ]. PPD films, especially those prepared by electropolymerization, have indeed been used in the past for the assembly of electrochemical sensors simply exploiting their permeability/permselectivity properties which were demonstrated to be significantly affected by polymerization conditions (e.g., potentiostatic or potentiodynamic deposition, pH).…”

Electrochemical Sensor Based on a Composite of Reduced Graphene Oxide and Molecularly Imprinted Copolymer of Polyaniline–Poly(o-phenylenediamine) for Ciprofloxacin Determination: Fabrication, Characterization, and Performance Evaluation

“…It has recently received significant attention owing to its high selectivity and sensitivity toward targets. Applications of MIP have been demonstrated in drug delivery, , solid-phase extraction coupled with liquid chromatography, , catalysis, , and environmental and biomedical sensing. − Various techniques have been utilized to synthesize MIP layers, including free-radical polymerization, chemical grafting, soft lithographies, molecular self-assembly, and electropolymerization. , Among these techniques, electropolymerization is a practical approach for MIP synthesis because a target molecule can be added to the electrolyte and entrapped in a conductive polymeric film. The molecules are sequentially extracted or leached out of the external polymeric surfaces to create recognition sites for MIP.…”

“… 13 − 15 Various techniques have been utilized to synthesize MIP layers, including free-radical polymerization, chemical grafting, 16 soft lithographies, 17 molecular self-assembly, 18 and electropolymerization. 19 , 20 Among these techniques, electropolymerization is a practical approach for MIP synthesis because a target molecule can be added to the electrolyte and entrapped in a conductive polymeric film. The molecules are sequentially extracted or leached out of the external polymeric surfaces to create recognition sites for MIP.…”