Glassy Carbon Electrode In Presence Research Articles

MWCNT modified glassy carbon electrode in presence of cationic surfactant for the electro-analysis of paclitaxel

A highly sensitive electrochemical sensor was constructed by layering a MWCNT on a glassy carbon electrode in presence of cationic surfactant, cetyltrimethyl ammonium bromide (CTAB). Surface morphology of developed sensor was carried by AFM technique and used for the electrochemical detection of an anticancer drug paclitaxel (PAC) in pure and dosage form by cyclic and differential pulse voltammetric techniques. Results showed modified sensor exhibited high specific surface area and its morphology consists of very thick and fine particles of MWCNT in presence of surfactant. Optimized the experimental condition by varying the surfactant concentration, accumulation time, buffer pH and scan rate. With standard pH of 7.0, for different scan rate variation (25 to 300 mV/s) a diffusion controlled surface phenomenon was observed on constructed sensor. Detailed electro-chemical oxidation mechanism was proposed based on the obtained result. MWCNT-CTAB/GCE provided lower detection limit and lower quantification limit of 4.38 × 10−10 M and 1.46 × 10−9 M respectively over the concentration ranges of 10.0 × 10−8 and 12.0 × 10−6 M.The MWCNT-CTAB/GCE was successfully applied for recovery of analyte in real sample and pharmaceutical sample. A good recovery percentage with lower RSD values depicts the sensitivity and selectivity of the sensor.

Amperometry detection of nitrite in food samples using tetrasulfonated copper phthalocyanine modified glassy carbon electrode

A stable chitosan protected tetrasulfonated copper phthalocyanine (Chit-TsCuPc) modified glassy carbon electrode (GCE) was used to aid the electrochemical detection of nitrite (NO2−) in food samples. The electrochemical oxidation of NO2− was investigated on bare, chitosan and TsCuPc modified GCE in presence of phosphate buffer solution with an acidic medium. The elevated oxidation peak current was noticed at less oxidation potential for + 0.55 V vs. Ag/AgCl at Chit-TsCuPc modified electrode under the optimized experimental conditions. The plot displays the peak current against NO2− with a good linearity in the concentration rangefrom 6.5 × 10−8 M to 5.0 × 10−10M. The linear regression equation is calculated to be Ip (μA) = 0.5291 + 1.4894C (NO2−), has a good correlation coefficient of 0.9949 and the detection limit of 22 nM (S/N = 3) with the current sensitivity of 4.964 μA nM−1 cm−2. The standard addition method was adopted to measure the unknown NO2− concentration in food samples.

Determination of the formation and range of stability of the SEI on glassy carbon by local electrochemistry

The formation of the solid electrolyte interphase was detected in operando on glassy carbon electrodes in presence of different cations.

Electrochemical Homogenous Catalysis of the Isoflurane Reduction in Presence of Iron(III) Tetraphenylporphyrin Chloride

The electrochemical reduction of the inhalational anesthetic agent isoflurane was studied at glassy carbon electrode in presence of iron(III) tetraphenylporphyrin chloride (Fe(TPP)Cl) in dimethyl sulfoxide (DMSO) solution. The ability of Fe(TPP)Cl as potential homogenous catalyst for the reduction of isoflurane was tested by cyclic voltammetry and chronomperometry. It showed excellent electrocatalytic ability for the reduction of isoflurane with overpotential of about 1150 mV more positive than the potential for observed reduction of isoflurane in DMSO solution. A linear range between 3.0 × 10-5 and 2.1 × 10-4 mol L-1 for the determination of isoflurane in DMSO solution containing 0.04 mmol L-1 Fe(TPP)Cl was obtained from cyclic voltammetry measurements. The limit of detection was estimated at 1.8 × 10-5 mol L-1. A possible catalytic mechanism is proposed.

A Novel Amperometric Sensor for Salicylic Acid Based on Molecularly Imprinted Polymer-Modified Electrodes

A novel electrochemical MIP-sensor for salicylic acid (SA) has been synthesized firstly by electropolymerizing o-phenylenediamine on glassy carbon electrode in presence of template molecule (salicylic acid). The response of the sensor to SA is investigated by square wave voltammetry (SWV). The linearity is obtained over a concentration range of 6 × 10−5 ∼ 1 × 10−4 mol/L (R2 = 0.9961). And the detection limit of SA is about 2 × 10−5 mol/L. The sensor exhibits good selectivity for salicylic acid by virtue of the interaction between molecularly imprinted binding sites and the template.

Bia-amperometric quantification of salbutamol in pharmaceutical products

This paper presents a simple, rapid and reproducible method of analysis of salbutamol in pharmaceutical products, utilizing batch injection analysis (BIA) associated with amperometric detection. A study of salbutamol oxidation demonstrated a strong dependence between electrode fouling and pH. All determinations were done utilizing a glassy carbon electrode in presence of 3.0 mol l −1 NaOH. A large linear dynamic range from 8×10 −7 to 2×10 −4 mol l −1 was obtained by using an injected volume of 100 μl with a detection limit of 2.5×10 −7 mol l −1. R.S.D. of 0.92% for 50 successive injections of 4×10 −6 mol l −1 of salbutamol and a sample throughput of 60 samples per hour were achieved. The method was applied for salbutamol quantification in syrups.