Rapid inexpensive assay method for verapamil by spectrophotometric sequential injection analysis

Area of Science:

• Analytical Chemistry
• Spectrophotometry
• Pharmaceutical Analysis

Background:

• Verapamil is a crucial cardiovascular drug.
• Accurate quantification of verapamil in pharmaceutical formulations is essential for quality control.
• Existing analytical methods may have limitations in speed, cost, or environmental impact.

Purpose of the Study:

• To develop and validate a novel, rapid, and environmentally friendly analytical method for verapamil determination.
• To optimize the method using a 2(3) full-factorial design.
• To assess the method's selectivity and accuracy in pharmaceutical samples.

Main Methods:

• Sequential Injection Analysis (SIA) coupled with miniaturized fiber optic spectrophotometry.
• Spectrophotometric detection of verapamil-induced reduction of acidified permanganate at 546 nm.
• Optimization using a 2(3) full-factorial design to evaluate critical parameters.

Main Results:

• The method achieved high sample throughput (10.6 samples/h) with minimal reagent and sample consumption (190 µl).
• Demonstrated excellent environmental safety with low waste production (2140 µl).
• Showed high selectivity in the presence of common pharmaceutical excipients, with recovery rates between 98.8-103.0%.

Conclusions:

• The developed SIA method is rapid, cost-effective, and environmentally benign for verapamil assay.
• The method is selective and accurate, suitable for routine quality control of verapamil in pharmaceutical formulations.
• Results are comparable to the British Pharmacopoeia method, indicating its reliability.