Clotrimazole (CLZ) is an imidazole derivative which is therapeutically used as an antifungal drug. The routine control analysis of CLZ requires rapid, reliable, accurate and precise methods for the quantification of drug in its pharmaceutical formulations. Spectrophotometric methods are presented for the determination of antifungal agent which were based on the charge transfer complexation reaction of CLZ with π-acceptors; tetracyanoethylene (TCE) and 7,7′,8,8′-tetracyanoquinodimethane (TCNQ). The formation of colored complexes were quantitated at 396 nm and 842 nm for CLZ-TCE and CLZ-TCNQ, respectively which enabled the development of simple and accurate spectrophotometric methods for the analysis of CLZ in pure drug substance and its pharmaceutical products. Under the optimum reaction conditions, linear relationships with appreciable correlation coefficients (0.9985-0.9994) were found between the absorbance at the relevant maxima and the concentrations of CLZ in the range of 5.00–35.00 μg mL−1 for CLZ-TCE and 1.00–25.00 μg mL−1 for CLZ-TCNQ complex. The molar absorptivities and Sandell's sensitivity values were also statistically evaluated. The proposed methods were successfully applied to analyze CLZ in topical creams and sterile solution with mean recovery percentages in the range of 99.60–100.20%, which indicated no interference from the inactive ingredients. Further, the charge transfer complexes of CLZ were also characterized by FT-IR spectroscopy.
Clotrimazole; Charge transfer complexes; Tetracyanoethylene; 7,7′,8,8′-Tetracyanoquinodimethane; FTIR characterization
Citation: Nasrin Banu Shaikh Ismail, Badiadka Narayana Spectrophotometric And Spectroscopic Studies On Charge Transfer Complexes Of Antifungal Drug Clotrimazole http://dx.doi.org/10.1016/j.jtusci.2016.08.002.
Received: 30 March 2016, Revised: 11 July 2016, Accepted: 12 August 2016, Available online: 31 August 2016
Copyright: © 2016 Elsevier B.V. or its licensors or contributors. ScienceDirect ® is a registered trademark of Elsevier B.V.
The determination of small amounts of CLZ in pharmaceutical preparations is important for medical needs; hence two simple spectrophotometric procedures are developed for the quantification of drug which is specific and cost-effective. The proposed methods also have the advantage of being a single step reaction using a single solvent and it can also be directly applied for the determination of CLZ in dosage forms containing parabens as the excipients, without the requirement of any tedious, time consuming drug isolation procedure. Hence, the suggested charge transfer complexation reaction is practical and economical for routine analysis of CLZ in control laboratories. In addition, the characterization of synthesized charge transfer complex by infrared spectroscopy has also been described.
The authors would like to acknowledge CAD Pharma Inc., Bangalore for gifting the drug sample. The authors would also like to thank Mangalore University for providing required research facilities to carry out the present work and University Grants Commission for financial assistance through BSR one time grant (SR/S9/Z-23/2010/32 dated 15/03/2011) for the purchase of chemicals.