Selective detection of dopamine in the presence of ascorbic acid using carbon nanotube modified screen-printed electrodes

Towards a blocking-free electrochemical immunosensing strategy for anti-transglutaminase antibodies using screen-printed electrodes

“…A constant potential of +1.00 V was applied for 60 s to activate the working electrode. The application of this potential may help to the activation of the carbon electrode surface, creating oxygenated functional groups and increasing the electroactive area, as previously described in the literature [33][34][35]. Furthermore, it is likely that the oxygen gas detaches part of the protein adsorbed on the electrode surface, leaving a more available surface for the subsequent deposition of cadmium.…”

“…Screen-printed electrodes are hydrophobic due to the ink components used in the manufacture (typically polyvinyl chloride and organic resins), normally forming a hydrogen-terminated electrode surface. In order to create a hydrophilic surface, other authors employ time-consuming electrochemical pretreatments to generate oxygenated groups [35] or even ultrasonic polishing with alumina [38]. In the latter case, the improvement on the immobilization of catechol derivatives was described after the activation.…”

Back‐to‐Back Screen‐Printed Electroanalytical Sensors: Extending the Potential Applications of the Simplistic Design

“…Analysis of ap hosphate buffer solution( PBS) containing5 0mMD Awas firstc arried out utilisingB -CNT-SPEs and B 2 -CNT-SPEs.F igure 3A depicts cyclic voltammograms of DA,i ti sc lear that an oxidation peak is present at~+ 0.00 Vw hich is in good agreement with literature,r epresenting carbon/graphite electrode surface [30][31][32][33].S can rate studies (over the range of 5t o4 00 mV s À1 )u singb oth electrode configurations was performed with analysis of the voltammetricr esponses in the form of peak height vs. square root scan rate was found to be linear in both cases,s uggesting ad iffusional controlled process operatinga te ach electrode surface;B -CNT-SPEs: I p (mA) = 6.09 10 À1 mA/(V s Figure 3B) is noted to double (~1.9 times improvement) upon implementation of the B 2 -CNT-SPEso ver the B-CNT-SPEs( see Figure 3A), such ar esponse indicates the benefit of using the back-toback configuration. Thel imits of detection (3s)f or dopaminea re found to correspond to 11.1 mMa nd 1.13 mMf or B-CNT-SPEs and B 2 -CNT-SPEsr espectively,c ompared to other literaturec oncerning modified carbon electrodes these values are very competitive.V alentini et al [34] explored the electroanalytical capabilitieso fg raphene modified macroelectrodes with limit of detectiono f 4.00 mM, however upon utilisation of CNT modified macroelectrode SPEs,M oreno et al [35] exhibitedavalue corresponding to 0.015 mM, whichi sd ue to the utilisation of adsorptive stripping voltammetry.…”

Electrosynthesis, Characterization and Electrocatalytic Behaviour of Organic-Metal Thin-Films Based on 2,2’-Bithiophene-5-carboxylic Acid and Metal Ions

“…Among of them, the electrochemical determination method is very accurate with high selectivity and best sensitivity. It is recognized as one of the most approaches for the separation of biological compounds such as ascorbic acid and dopamine [18][19][20]. Therefore, this advantage has a significant attraction in biological and electrochemical research.…”