Design of Nanostructured Hybrid Electrodes Based on a Liquid Crystalline Zn(II) Coordination Complex-Carbon Nanotubes Composition for the Specific Electrochemical Sensing of Uric Acid

Abstract

A metallomesogen based on an Zn(II) coordination complex was employed as precursor to obtain a complex matrix nanoplatform for the fabrication of a high-performance electrochemical hybrid sensor. Three representative paste electrodes, which differ by the weight ratio between Zn(II) metallomesogen and carbon nanotubes (CNT), i.e., PE_01, PE_02 and PE_03, were obtained by mixing the materials in different amounts. The composition with the largest amount of CNT with respect to Zn complex, i.e., PE_03, gives the best electrochemical signal for uric acid detection by cyclic voltammetry in an alkaline medium. The amphiphilic structure of the Zn(II) coordination complex likely induces a regular separation between the metal centers favoring the redox system through their reduction, followed by stripping, and is characterized by enhanced electrocatalytic activity towards uric acid oxidation. The comparative detection of uric acid between the PE_03 paste electrode and the commercial zinc electrode demonstrated the superiority of the former, and its great potential for the development of advanced electrochemical detection of uric acid. Advanced electrochemical techniques, such as differential-pulsed voltammetry (DPV) and square-wave voltammetry (SWV), allowed for the highly sensitive detection of uric acid in aqueous alkaline solutions. In addition, a good and fast amperometric signal for uric acid detection was achieved by multiple-pulsed amperometry, which was validated by urine analysis.

New Trends in Uric Acid Electroanalysis

“…The latest research is investigating sensors based on carbon nanotubes modified with lanthanum hydroxide (La(OH) 3 ) [112], Zn_MM [113], cobalt phthalocyanine [107] or bentonite (Bent) and L-cysteine [114].…”

Recent trends in nanostructured carbon-based electrochemical sensors for the detection and remediation of persistent toxic substances in real-time analysis

“…To manufacture a high-activity electrochemical blended sensor, Negrea et al [94] used a complicated matrices nanoplatform made from a metallomesogen centered on a Zn(II) coordination compound as a precursor. By combining the components in varying ratios, PE 01, PE 02, and PE 03, three typical paste electrodes that varied by the wt.…”

Role of the Environment Polarity on the Photophysical Properties of Mesogenic Hetero-Polymetallic Complexes

“…2,2′:6′,2″-terpyridine ( tpy ) and its derivatives are important chelating ligands in coordination and supramolecular chemistry, yielding complexes with excellent electronic, optical and electrochemical properties [ 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 ]. Their coordination complexes, based on the cheap biocompatible and bioavailable Zn(II) metal center, were successfully used for obtaining polarized emissions [ 21 ] and emissive materials for optoelectronics and luminescence-based technologies [ 22 , 23 ], sensing and detection [ 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 ], DNA binding and/or cleavage agents [ 34 , 35 , 36 , 37 ] and bioimaging [ 38 , 39 , 40 ].…”

“…luminescence-based technologies [22,23], sensing and detection [24][25][26][27][28][29][30][31][32][33], DNA binding and/or cleavage agents [34][35][36][37] and bioimaging [38][39][40].…”