Enhancement of Solubility of Poorly Soluble Drug Using Drug Solution Dropping Technique

Abstract- The objective of the present study is to improve dissolution rate of poorly soluble drug from tablet by drugsolution-dropping-technique. Carvedilol was used as a model drug. Carvedilol is a nonselective beta-adrenergic blocking agent with alpha1-blocking activity and is indicated for the treatment of hypertension and mild or moderate heart failure of ischemic or cardiomyopathic origin. Dichloromethane was use to prepare carvedilol drug solution. The drug solution was dropped on tablet by using microsyringe. Blank tablets were prepared by direct compression (DC) method by using dicalciumphosphatedihydrate as diluents. Different types and concentration of superdisintegrants were used. The different superdisintegrants used were sodium starch glycolate, croscarmaellose sodium and crospovidone. The tablets were subjected to thickness, weight variation test, drug content, hardness, friability and invitro release studies. The results were found within the limits. The USP paddle method was selected to perform the dissolution profiles carried out by USP apparatus 2 (paddle) at 50 rpm in 900 ml of 0.1 N HCL. Dissolution profiles of the prepared tablet from the blank tablets were compared to carvedilol tablet prepared by the conventional direct compression method. The surfaces of carvedilol drug-solution-droppingtablets were characterized by scanning electron microscope. Their morphologies revealed the smoother but not being clear to point out carvedilol particles on the surface of the tablet. FTIR studies showed that there was no interaction between drug and excipients. Hence it can be concluded that drug solution dropping technique can be regarded as a novel technique to improve dissolution properties of potent drugs belonging to BCS class II.