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- Gajda, Marianna, et al.
(författare)
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Low-oxidation-potential thiophene-carbazole monomers for electro-oxidative molecular imprinting: Selective chemosensing of aripiprazole
- 2020
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Ingår i: Biosensors & bioelectronics. - : ELSEVIER ADVANCED TECHNOLOGY. - 0956-5663 .- 1873-4235. ; 169
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Tidskriftsartikel (refereegranskat)abstract
- New thiophene-carbazole functional and cross-linking monomers electropolymerizing at potentials sufficiently low for molecular imprinting of an electroactive aripiprazole antipsychotic drug were herein designed and synthesized. Numerous conducting molecularly imprinted polymer (MIP) films are deposited by electro-polymerization at relatively low potentials by electm-oxidation of pyrmle, aniline, phenol, or 3,4-ethylenediox-ythiophene (EDOT). However, their interactions with templates are not sufficiently strong. Hence, it is necessary to introduce additional recognizing sites in these cavities to increase their affinity to the target molecules. For that, functional monomers derivatized with substituents forming stable complexes with the templates are used. However, oxidation potentials of these derivatives are often, disadvantageously, higher than that of parent monomers. Therefore, we designed and synthesized new functional and cross-linking monomers, which are oxidized at sufficiently low potentials. The deposited MIP and non-imprinted polymer (NIP) films were characterized by PM-IRRAS and UV-vis spectroscopy and imaged with AFM. The structure of the aripiprazole prepolymerization complex with functional monomers was optimized with density functional theory (DFT), and aripiprazole interactions with imprinted cavities were simulated with molecular mechanics (MM) and molecular dynamics (MD). MIP-aripiprazole film-coated electrodes were used as extended gates for selective determination of aripiprazole with the extended-gate field-effect transistor (EG-FET) chemosensor. The linear dynamic concentration range was 30-300 pM, and the limit of detection was 22 fM. An apparent imprinting factor of the MIP-1 was IF = 4.95. The devised chemosensor was highly selective to glucose, urea, and creatinine interferences. The chemosensor was successfully applied for aripiprazole determination in human plasma. The results obtained were compared to those of the validated HPLC-MS method.
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| 2. |
- Yadav, Jyoti, et al.
(författare)
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Cilostazol-imprinted polymer film-coated electrode as an electrochemical chemosensor for selective determination of cilostazol and its active primary metabolite
- 2022
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Ingår i: Journal of materials chemistry. B. - : ROYAL SOC CHEMISTRY. - 2050-750X .- 2050-7518. ; 10:35, s. 6707-6715
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Tidskriftsartikel (refereegranskat)abstract
- An electrochemical chemosensor for cilostazol (CIL) determination was devised, engineered, and tested. For that, a unique conducting film of the functionalized thiophene-appended carbazole-based polymer, molecularly imprinted with cilostazol (MIP-CIL), was potentiodynamically deposited on a Pt disk electrode by oxidative electropolymerization. Thanks to electro-oxidation potentials lower than that of CIL, the carbazole monomers outperformed pyrrole, thiophene, and phenol monomers, in this electropolymerization. The pre-polymerization complexes quantum-mechanical and molecular dynamics analysis allowed selecting the most appropriate monomer from the three thiophene-appended carbazoles examined. The electrode was then used as a selective CIL chemosensor in the linear dynamic concentration range of 50 to 924 nM with a high apparent imprinting factor, IF = 10.6. The MIP-CIL responded similarly to CIL and CILs pharmacologically active primary metabolite, 3,4-dehydrocilostazol (dhCIL), thus proving suitable for their determination together. Simulated models of the MIP cavities binding of the CIL, dhCIL, and interferences molecules allowed predicting chemosensor selectivity. The MIP film sorption of CIL and dhCIL was examined using DPV by peak current data fitting with the Langmuir (L), Freundlich (F), and Langmuir-Freundlich (LF) isotherms. The LF isotherm best described this sorption with the sorption equilibrium constant (K-LF) for CIL and dhCIL of 12.75 x 10(-6) and 0.23 x 10(-6) M, respectively. Moreover, the chemosensor cross-reactivity to common interferences study resulted in the selectivity to cholesterol and dehydroaripiprazole of 1.52 and 8.0, respectively. The chemosensor proved helpful in determining CIL and dhCIL in spiked human plasma with appreciable recovery (99.3-134.1%) and limit of detection (15 nM).
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