MyMedR

Displaying all 6 publications

Abstract:

Sort:

Photoelectrocatalytic mechanism of PEDOT modified filtration membrane

Shi L, Liu J, Gao B, Sillanpää M

Sci Total Environ, 2022 Mar 20;813:152397.
PMID: 34923007 DOI: 10.1016/j.scitotenv.2021.152397

The generation of free radicals is the key to the photocatalytic efficiency. In this study, the degradation mechanism of photoelectrocatalysis (PEC) membrane could be adequately explained by exploring the generation pathway of different free radicals. The PEC membrane was prepared by gas phase polymerization of poly (3, 4-ethylene dioxythiophene) (PEDOT) on non-woven fabric, industrial filter cloth, ceramic membrane and polyvinylidene fluoride (PVDF) membrane, respectively. Three-dimensional fluorescence test showed that the optimal degradation of mixed or monomer contamination (bovine serum protein, sodium humate, and sodium alginate) was achieved by modified ceramic membrane under PEC condition. As for self-cleaning experiment, the membrane resistance decreased 65.7% when the reaction conditions changed from dark to PEC for 30 min. Combined with the characterization results, PEDOT as photocapacitance extended electron lifetime and promoted free radical generation. This system was mainly dependent on superoxide free radicals (0.01 mmol/L) and singlet oxygen (0.10 mmol/L), which came from energy and electron transfer. Oxygen vacancy could adsorb oxygen to produce superoxide radicals, which was further oxidized to singlet oxygen. In addition, the π-electron conjugated system of PEDOT accelerated the hole transfer and the separation of electrons and holes. Also, this study provided a new view of reactive oxygen species generation mechanism from PEDOT modified membrane.

Matched MeSH terms: Bicyclo Compounds, Heterocyclic*
PEDOT coated microneedles towards electrochemically assisted skin sampling

Ajmal Mokhtar SM, Yamada M, Prow TW, Moore M, Strudwick XL, Evans DR

J Mater Chem B, 2023 Jun 07;11(22):5021-5031.
PMID: 37226634 DOI: 10.1039/d3tb00485f

Skin sampling is a diagnostic procedure based on the analysis of extracted skin tissues and/or the observation of biomarkers in bodily fluids. Sampling using microneedles (MNs) that minimize invasiveness is gaining attention over conventional biopsy/blood lancet. In this study, new MNs for electrochemically assisted skin sampling are reported, specifically tailored for combined skin tissue biopsy and interstitial fluid (ISF) extraction. To overcome risks associated with using metal MNs, a highly electroactive, mechanically flexible, and biocompatible organic conducting polymer (CP) coated onto plastic is chosen as an alternative. Two different variants of doped poly(3,4-ethylenedioxythiophene) are coated on polymethyl methacrylate and used in combination as a MN pair with subsequent testing via a variety of electrochemical techniques to (i) give real-time information of the MN penetration depth into the skin, and (ii) yield new information on various salts present in the ISF. The MN skin sampler shows the ability to extract ions from the hydrated excised skin as a step towards in vivo ISF extraction. The presence of ions was analyzed using X-ray photoelectron spectroscopy. This added chemical information in conjunction with the existing biomarker analysis increases opportunity for disease/condition detection. For example, in the case of psoriasis, information about salt in the skin is invaluable in combination with pathogenic gene expression for diagnosis.

Matched MeSH terms: Bicyclo Compounds, Heterocyclic
Comparative pharmacokinetic study of oral and rectal formulations of artesunic acid in healthy volunteers

Navaratnam V, Mansor SM, Mordi MN, Akbar A, Abdullah MN

Eur J Clin Pharmacol, 1998 Jul;54(5):411-4.
PMID: 9754985

OBJECTIVE: A single cross-over, comparative pharmacokinetic study of oral and rectal formulations of 200 mg artesunic acid in 12 healthy Malaysian volunteers is reported.
METHODS: Plasma concentrations of artesunic acid and dihydroartemisinin were determined simultaneously by HPLC with electrochemical detection. The test drug was well tolerated and no undesirable adverse effects were observed.
RESULTS: Comparison of pharmacokinetic parameters of artesunic acid after oral and rectal administration showed statistically significant differences in t(max) and AUC, with no changes for Cmax and t1/2. As for dihydroartemisinin, differences were observed for t(max) and Cmax but not for AUC.
CONCLUSION: There appear to be pharmacokinetic differences between oral and rectal modes of administration. The significance of these findings should be explored in malaria patients before appropriate therapeutic regimens are devised.

Matched MeSH terms: Bicyclo Compounds, Heterocyclic/administration & dosage; Bicyclo Compounds, Heterocyclic/blood; Bicyclo Compounds, Heterocyclic/pharmacokinetics*
Coumarins and other fused bicyclic heterocycles with selective tumor-associated carbonic anhydrase isoforms inhibitory activity

Bozdag M, Alafeefy AM, Altamimi AM, Vullo D, Carta F, Supuran CT

Bioorg Med Chem, 2017 01 15;25(2):677-683.
PMID: 27939347 DOI: 10.1016/j.bmc.2016.11.039

Herein we report for the first time a series of 2-benzamido-N-(2-oxo-4-(methyl/trifluoromethyl)-2H-chromen-7-yl) benzamide 3a-f and substituted quinazolin-4(3H)-ones and 2H-benzo[e][1,2,4]thiadiazin-3(4H)-one 1,1-dioxides (5, 6, 8 and 10a-c) as selective inhibitors of the tumor associated hCA IX and XII isoforms. Among the compounds reported the trifluoromethyl derivative 3d resulted the most potent against these CA isoforms with KIs of 10.9 and 6.7nM.

Matched MeSH terms: Bicyclo Compounds, Heterocyclic/chemical synthesis; Bicyclo Compounds, Heterocyclic/pharmacology*; Bicyclo Compounds, Heterocyclic/chemistry
Synergetic effect of conductive polymer poly(3,4-ethylenedioxythiophene) with different structural configuration of anode for microbial fuel cell application

Kang YL, Ibrahim S, Pichiah S

Bioresour Technol, 2015;189:364-369.
PMID: 25913883 DOI: 10.1016/j.biortech.2015.04.044

PEDOT was synthesized by chemical polymerisation and characterised for its electrochemical insights. Three different anode configuration, namely graphite plate (GP), carbon cloth (CC) and graphite felt (GF) were then loaded with a fixed amount of PEDOT (2.5 mg/m(2)) denoted as GP-P, CC-P and GF-P respectively. The PEDOT coating improved the electrochemical characteristics and electron transfer capabilities of the anodes. They also contributed for enhanced MFC performances with maximum energy generation along with coulombic efficiency than the unmodified anodes. The morphological characteristics like higher surface area and open structure of felt material promoted both microbial formation and electrochemical active area. A maximum current density of 3.5A/m(2) was achieved for GF-P with CE and COD of 51% and 86% respectively. Thus, the GF-P anode excelled among the studied anodes with synergetic effect of PEDOT coating and structural configuration, making it as a potential optimum anode for MFC application.

Matched MeSH terms: Bicyclo Compounds, Heterocyclic/chemistry*
Fulltext Development of Highly Sensitive Immunosensor for Clenbuterol Detection by Using Poly(3,4-ethylenedioxythiophene)/Graphene Oxide Modified Screen-Printed Carbon Electrode

Talib NAA, Salam F, Sulaiman Y

Sensors (Basel), 2018 Dec 07;18(12).
PMID: 30544568 DOI: 10.3390/s18124324

Clenbuterol (CLB) is an antibiotic and illegal growth promoter drug that has a long half-life and easily remains as residue and contaminates the animal-based food product that leads to various health problems. In this work, electrochemical immunosensor based on poly(3,4-ethylenedioxythiophene)/graphene oxide (PEDOT/GO) modified screen-printed carbon electrode (SPCE) for CLB detection was developed for antibiotic monitoring in a food product. The modification of SPCE with PEDOT/GO as a sensor platform was performed through electropolymerization, while the electrochemical assay was accomplished while using direct competitive format in which the free CLB and clenbuterol-horseradish peroxidase (CLB-HRP) in the solution will compete to form binding with the polyclonal anti-clenbuterol antibody (Ab) immobilized onto the modified electrode surface. A linear standard CLB calibration curve with R² = 0.9619 and low limit of detection (0.196 ng mL-1) was reported. Analysis of milk samples indicated that this immunosensor was able to detect CLB in real samples and the results that were obtained were comparable with enzyme-linked immunosorbent assays (ELISA).

Matched MeSH terms: Bicyclo Compounds, Heterocyclic/chemistry