Ultra violet spectrophotometric method: Not possible for the simultaneous estimation of alpha one adrenoreceptor blockers

Abstract

Background: Although initially introduced for the management of hypertension, αladrenergic-receptor antagonists (α1 blockers) have become the standard of care for the
medical management of benign prostatic hyperplasia (BPH)-related lower urinary tract
symptoms (LUTS). Alpha-blockers (alfuzosin, tamsulosin, doxazosin, prazosin, and
terazosin) relax the smooth muscles in the prostate and are indicated for the symptomatic
treatment of BPH, due to evidence of their positive and rapid effect on LUTS. Objective:
Our objective was to develop and validate a method for simultaneous estimation of
these drugs. Our aim was to develop a UV spectrophotometric method because of
the simplicity and economical advantage of this technique. Materials and Methods:
All these drugs were dissolved in the same solvent (methanol) and scanned under a
ShimadzuUV spectrophotomer, under full UV (ultraviolet) range (200 – 400 nm).
Result:After some experiments we found that this is impossible. This was evident from
our study that UV spectra were overlapping each other, except in the case of tamsulosin.
Conclusion: Same class of drugs may have almost the same functional groups, and
gradient Reverse-Phase Liquid Chromatography(RPLC) will be more useful to
separate such complicated mixtures. Therefore, we propose to develop a gradient HighPerformance Liquid Chromatography(HPLC) method as it may be a more suitable
method for the simultaneous estimation of these drugs.