AN UPDATE ON VARIOUS ANALYTICAL TECHNIQUES BASED ON UV SPECTROSCOPY USED IN DETERMINATION OF DISSOCIATION CONSTANT

Bebee Pathare*, Vrushali Tambe, Shashikant Dhole, Vandana Patil

It is well known that the dissociation constant is most important parameter in development and optimization of new compound for effective formulation development. Dissociation constant plays a crucial role in understanding chemical phenomenon of drug because it affects pharmacokinetic behavior like absorption, distribution, metabolism, and elimination (ADME). Solubility, permeability, protein binding of a compound is also influenced by its pKa. There are various techniques available for determination of dissociation constant. Among Photometric techniques available, ultraviolet-visible spectrophotometry is one of the most frequently employed technique in pharmaceutical analysis for determination of this parameter. In this review the most valuable UV spectroscopic methods such as derivative spectrophotometry, simultaneous equation method, orthogonal polynomial method, multi-wavelength method, molar ratio method, difference spectrophotometry for determining accurate pKa value are presented.