Electro-reduced graphene oxide film modified glassy carbon electrode as an electrochemical sensor for sibutramine

Simple and Sensitive Determination of Sibutramine in Slimming Tea Beverages Using a Carbon Screen‐printed Electrode with Adsorptive Stripping Voltammetry

“…Peak currents from this oxidation (ca. + 0.5 V (vs (Ag)) were linearly proportional to scan rate (inset Figure 3) with a linear regression coefficient (r 2 ) of 0.995 for I pa (mA) = 4.6 AE 1.8 + 723.6 AE 19.7 v (V s À1 ), indicating that this electrochemical process is adsorption-controlled at the SPE-Gr, which has also been reported for graphene modified electrode [21], but not at BDDE where it is diffusion-controlled [17]. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58…”

“…Peak currents from this oxidation (ca. +0.5 V ( vs (Ag)) were linearly proportional to scan rate (inset Figure ) with a linear regression coefficient (r 2 ) of 0.995 for I pa (μA)=4.6±1.8+723.6±19.7 v (V s −1 ), indicating that this electrochemical process is adsorption‐controlled at the SPE‐Gr, which has also been reported for graphene modified electrode , but not at BDDE where it is diffusion‐controlled .…”

“…The oxidation processes shown in Figure A for a sibutramine solution at SPE‐Gr have also been reported in pH 7.0 using a bare or modified GCEs and BDDE . Note that for pH above 8.0 to 9.0, the sibutramine becomes less soluble in aqueous solutions due to the non‐protonation of the amine group (pKa 9.8) , which can explain the absence of oxidation peaks for this stimulant in pH >9.0 (Figure B).…”

“…In addition, the adsorptive stripping voltammetry (AdSV) technique is an 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 excellent approach for increasing the sensitivity of electrochemical detection in which the analyte adsorbs on the electrode surface [20]. Sibutramine has shown an electrochemical oxidation process that is adsorption-controlled at electro-reduced graphene oxide film modified glassy carbon electrode (ERGO-GCE) [21], which was applied for determination of this drug in urine and human serum.…”

Electrochemical Investigations of Biomolecules Using Carbon Nanotube and Graphene Based Modified Electrodes

“…Hence, the electrode, CrGO/GCE was utilized to develop electroanalytical method for the sensitive determination of VAR with detection limit of 7.03 nM [25]. The same research group also exploited the use of ErGO modified GCE for sensing of various drug molecules in pharmaceutical formulations [26][27][28]. ErGO/GCE was fabricated by applying potential in the range of -1.6 to 0.7 V to GO/GCE in phosphate buffer of pH of 6. was utilized to modify GCE for the sensitive determination of glucose in blood samples with a detection limit of 80 nM [29].…”