Imprinted polymer-modified hanging mercury drop electrode for differential pulse cathodic stripping voltammetric analysis of creatine.
The molecularly imprinted polymer [poly(p-aminobenzoicacid-co-1,2-dichloroethane)] film casting was made on the surface of a hanging mercury drop electrode by drop-coating method for the selective and sensitive evaluation of creatine in water, blood serum and pharmaceutical samples. The molecular recognition of creatine by the imprinted polymer was found to be specific via non-covalent (electrostatic) imprinting. The creatine binding could easily be detected by differential pulse, cathodic stripping voltammetric signal at optimised operational conditions: accumulation potential -0.01 V (versus Ag/AgCl), polymer deposition time 15s, template accumulation time 60s, pH 7.1 (supporting electrolyte< or =5 x 10(-4)M NaOH), scan rate 10 mV s(-1), pulse amplitude 25 mV. The modified sensor in the present study was found to be highly reproducible and selective with detection limit 0.11 ng mL(-1) of creatine. Cross-reactivity studies revealed no response to the addition of urea, creatinine and phenylalanine; however, some insignificant magnitude of current was observed for tryptophan and histidine in the test samples.
Lakshmi
Dhana
D
Analytical Division, Department of Chemistry, Faculty of Science, Banaras Hindu University, Varanasi 221005, India.
Sharma
Piyush S
PS
Prasad
Bhim B
BB
D015374:Biosensing Techniques; D003401:Creatine / Q000032:analysis* / Q000097:blood; D004563:Electrochemistry; D004566:Electrodes; D006801:Humans; D008628:Mercury / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*
D011108:Polymers; D008628:Mercury; D003401:Creatine