scholarly journals Linear sweep polarographic determination of nucleic acids using acridine orange as a bioprobe

2007 ◽  
Vol 72 (11) ◽  
pp. 1085-1094 ◽  
Author(s):  
Wei Sun ◽  
Na Zhao ◽  
Xianlong Yuan ◽  
Kui Jiao
Keyword(s):  
Aqueous Solution ◽  
Acridine Orange ◽  
Electrochemical Method ◽  
Electrochemical Determination ◽  
Determination Method ◽  
Linear Regression Equation ◽  
Peak Potential ◽  
Linear Sweep ◽  
Buffer Solution

The interaction of acridine orange (AO) with double-stranded (ds) DNA in aqueous solution was investigated by linear sweep polarography (LSP) on a dropping mercury working electrode (DME). In pH 2.5 Britton-Robinson (B-R) buffer solution, AO had a sensitive linear sweep polarographic reductive peak at -0.89 V (vs. SCE), which could be greatly inhibited by the addition of dsDNA, with a positive shift of the peak potential. Based on the decrease of the reductive peak current, a new quantitative electrochemical determination method for dsDNA was developed with a linear range of 2.0?20.0 mg l-1 and the linear regression equation: ?Ip" (nA) = 111.90 C (mg l-1)+125.32 (n = 9, ? = 0.997). The influences of commonly co-existing substances, such as metal ions, amino acid, etc., on the determination were also investigated. The method is sensitive, rapid and simple with good selectivity. The new proposed method was further applied to the detection of RNA and three synthetic samples containing dsDNA with satisfactory results. The binding number and the equilibrium constant between dsDNA and AO were calculated by an electrochemical method.

A simple linear sweep voltammetric method for the determination of double-stranded DNA with malachite green

2006 ◽  
Vol 60 (3) ◽  
Author(s):  
W. Sun ◽  
J. You ◽  
X. Hu ◽  
K. Jiao
Keyword(s):  
Malachite Green ◽  
Interaction Mechanism ◽  
High Sensitivity ◽  
Electrochemical Determination ◽  
Supramolecular Complex ◽  
Linear Sweep ◽  
Buffer Solution ◽  
Peak Current ◽  
Double Stranded Dna

AbstractIn pH 3.5 Britton—Robinson buffer solution double-stranded (ds) DNA can react with malachite green (MG) to form an interaction complex, which resulted in the decrease of the electrochemical response of MG, MG had a well-defined second-order derivative linear sweep voltammetric peak at −0.73 V (vs. SCE). After the addition of dsDNA into MG solution, the reductive peak current decreased with the positive shift of peak potential, which was the typical characteristic of intercalation. Based on the interaction, an indirect electrochemical determination method for dsDNA was established. The optimum conditions for the reaction were investigated and there were little or no interferences from the commonly coexisting substances. The decrease of peak current was linear with the concentration of dsDNA over the range of 0.8–12.0 µg cm−3 with the linear regression equation as ΔI p″/nA = 91.70 C/(µg cm−3) + 74.55 (n = 10, γ = 0.990). The detection limit was calculated as 0.46 µg cm−3 (3σ). The method had high sensitivity and was further applied to the dsDNA synthetic samples with satisfactory result. The interaction mechanism was discussed with the intercalation of DNA-MG to form a supramolecular complex and the stoichiometry of the supramolecular complex was calculated by electrochemical method with the binding number 3 and the binding constant 2.35 × 1015 (mol dm−3)−3.

Electrochemical Determination of Neomycin and Norfloxacin at a Novel Polymer Nanocomposite Electrode in Aqueous Solution

2017 ◽  
Vol 50 (12) ◽  
pp. 1887-1896 ◽  
Author(s):  
Siyabulela Hamnca ◽  
Lisebo Phelane ◽  
Emmanuel Iwuoha ◽  
Priscilla Baker
Keyword(s):  
Aqueous Solution ◽  
Polymer Nanocomposite ◽  
Electrochemical Determination

Electrochemical determination of selected antihypertensive and antituberculosis drugs at a tyrosine-modified electrode

2014 ◽  
Vol 6 (17) ◽  
pp. 6774-6782 ◽  
Author(s):  
Srikanth Cheemalapati ◽  
Balamurugan Devadas ◽  
Shen-Ming Chen ◽  
M. Ajmal Ali ◽  
Fahad M. A. Al-Hemaid
Keyword(s):  
Modified Electrode ◽  
Electrochemical Method ◽  
Electrochemical Determination ◽  
Antituberculosis Drugs ◽  
Hydralazine Hydrochloride

A simple and sensitive electrochemical method was proposed for the determination of hydralazine hydrochloride (HDH), isoniazid (ISN), ethambutol hydrochloride (EBH) and pyrazinamide (PZM).

scholarly journals A Novel Method for Determination of Protein in Human Serum Utilizing the Trihydroxylphenylfluorone-Molybdenum(VI) Complex as a Probe by Fluorescence Spectrometry

2007 ◽  
Vol 90 (1) ◽  
pp. 238-243 ◽  
Author(s):  
Qin Wei ◽  
Hongmin Ma ◽  
Caihong Duan ◽  
Jin Wang ◽  
Shuyuan Liu ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Amino Acids ◽  
Detection Limit ◽  
Human Serum ◽  
Fluorescence Intensity ◽  
Acetate Buffer Solution ◽  
Buffer Solution ◽  
Protein Assay ◽  
Novel Method

Abstract The fluorescence intensity of the trihydroxylphenylfluorone-molybdenum(VI) Mo(VI) complex is quenched by protein. Based on this, a novel method for protein assay in aqueous solution was developed. With pH 3.75 acetic acidsodium acetate buffer solution, in the presence of p-octyl polyethylene glycol phenyl ether microemulsion, the quenched fluorescence intensity is proportional to the concentration of bovine serum albumin (BSA) in the range of 07.00 μg/mL, and the detection limit of BSA is 5.65 ng/mL. There is no interference from amino acids and most metal ions. The method developed in this paper has been used for the successful determination of protein in human serum.

scholarly journals A novel dopamine electrochemical sensor based on La3+/ZnO nanoflower modified graphite screen printed electrode

2019 ◽  
Vol 9 (3) ◽  
pp. 187-195 ◽  
Author(s):  
Somayeh Tajik ◽  
Hadi Beitollahi ◽  
Mohammad Reza Aflatoonian
Keyword(s):  
Modified Electrode ◽  
Phosphate Buffer Solution ◽  
High Sensitivity ◽  
Differential Pulse ◽  
Electrochemical Determination ◽  
Screen Printed Electrode ◽  
Buffer Solution ◽  
Optimized Conditions ◽  
Screen Printed

Flower-like La3+/ZnO nanocomposite was facile synthesized. A simple and ultrasensitive sensor based on graphite screen printed electrode (SPE) modified by La3+/ZnO nanoflower was developed for the electrochemical determination of dopamine. The electrochemical behavior of dopamine was studied in 0.1 M phosphate buffer solution (PBS) using cyclic voltammetry (CV), chronoamperometry (CA) and differential pulse voltammetry (DPV). Compared with the unmodified graphite screen printed electrode, the modified electrode facilitates the electron transfer of dopamine, since it notably increases the oxidation peak current of dopamine. Also, according to CV results the maximum oxidation of dopamine on La3+/ZnO/SPE occurs at 150 mV which is about 140 mV more negative compared with unmodified SPE. Under optimized conditions, the modified electrode exhibited a linear response over the concentration range from 0.15 to 300.0 μM, with a detection limit of 0.08 μM (S/N = 3). The proposed sensor exhibited a high sensitivity, good stability and was successfully applied for dopamine determination in dopamine ampoule, with high recovery.

Immobilized copper ions on MWCNTS-Chitosan thin film: Enhanced amperometric sensor for electrochemical determination of diclofenac sodium in aqueous solution

2017 ◽  
Vol 42 (31) ◽  
pp. 19951-19960 ◽  
Author(s):  
Md Shalauddin ◽  
Shamima Akhter ◽  
Samira Bagheri ◽  
Mohd Sayuti Abd Karim ◽  
Nahrizul Adib Kadri ◽  
...  
Keyword(s):  
Thin Film ◽  
Aqueous Solution ◽  
Copper Ions ◽  
Diclofenac Sodium ◽  
Electrochemical Determination ◽  
Amperometric Sensor
Sign in / Sign up

Export Citation Format

Share Document