J. K. Pandit

Transdermal Delivery of Propranolol

Three transdermal formulations containing propranolol hydrochloride in a hydrophilic polymer matrix were prepared-one without a rate controlling membrane(H-1), one with a 20μ thick Ethylene Vinyl Acetate(EVA) rate controlling membrane (H-2) and one with a 65μ thick EVA membrane. These patches were evaluated for their in-vitro performance. Cumulative % permeated across excised hairfree rat skin were 79.2% from H-1, 65.53% from H-2 and 53.44% from H-3. Increase in thickness of EVA lead to greater retention of drug in device and a zero order profile was seen with patches H-2 & H-3. Matrix diffusion profile was observed with H-1 patch.

Carboxymethylcellulose‐sodium Based Transdermal Drug Delivery System for Propranolol

Propranolol, a β‐adrenoceptor blocker, suffers from a high degree of first‐pass metabolism resulting in very low bioavailability (<10%) following administration with conventional oral formulations. To circumvent this significant therapeutic hurdle, we formulated a carboxymethylcellulose‐sodium (CMC‐Na) based transdermal system for propranolol and evaluated the patch for its in‐vitro and in‐vivo performance.

Prolonged release of pentazocine from multiple O/W/O emulsions

AbstractMultiple O/W/O emulsions containing pentazocine were prepared and tested in vitro and in vivo. The effect of two different concentrations of three additives, viz. sodium chloride, glucose and glycerol, location of the drug either in one or any two phases of the O/W/O emulsions and pH of the receptor fluid on in vitro release characteristics of the drug was studied. All the parameters influenced the drug release. Multiple O/W/O emulsions gave higher extent of drug release than the simple O/W emulsions. The results of in vivo studies in mice showed prolonged tissue levels of pentazocine from the multiple O/W/O emulsions in comparison to aqueous drug solution and simple O/W emulsion.

In Vitro and Invivo Evaluation of Some Fast Release Dosage Forms of Hydrochlorothiazide

AbstractThe utilization of ternary sugar solid dispersion and solvent deposition systems for increasing the dissolution rate of hydrochlorothiazide (hot) were investigated. The dispersion systems were prepared by the fusion method using various combinations of mannitol and sorbitol, and urea and polyethylene glycol 4000 (peg 4000) were used for comparison. An 1:2 mixture of sorbitol-mannitol was found to be an excellent carrier. The dissolution rate of this sample was closely comparable to that of hot-peg 4000 solid dispersions. Drug-urea eutectic mixtures were inferior to both the sugar and polymer dispersions. Solvent deposition systems of hot with microfine cellulose and potato starch gave higher dissolution rates at the initial sampling times. It is proposed that solid dispersion systems of this drug may prove to be valuable. Tablets fabricated from fast-release hot granules showed better in vivo results than a marketed tablet. A linear relationship was observed between in vitro-in vivo data of some o...

Prolonged Tissue Levels of Pentazocine from Multiple W/O/W EMULSIONS IN MICE

AbstractMultiple W/O/W emulsions containing pentazocine were prepared and tested in virto and in viro. The in viro results indicated a well controlled and higher drug release from teh W/O/W emulsions than the W/O emulsion. The in vivo data showed prolonged tissue levels of pentazocine after oral administration of W/O/W emulsions than the W/O emulsion to mice in comparison to acquenous drug solution and W/O emulsion.

Relationship Between Dissolution Rate and Bioavailability of Sustained-Release Ibuprofen Capsules

AbstractDissolution studies of three marketed brands of ibuprofen sustained-release (SR) capsules were conducted on USP XIX dissolution apparatus 1, using buffers simulating the gastrointestinal tract (GIT) pHs. The products showed almost identical drug release pattern in dissolution studies. A single-dose crossover oral bioavailability study revealed statistically significant differences in Cmax, Tmax, AUC and percent bioavailability values among the SR products but no such differences are evident in the t1/2a, Ka, t1/2e, and Ke. Retard quotient values were used to evaluate the sustained-release nature of the products. Statistical moment parameters such as MRT, MAT, and MDT were related with the dissolution parameters. Statistically significant correlations were observed between MRTin vitro and MRTin vivo or MDTin vivo T50% and Tmax; and T90%, and Cmax, or AUC120. The determination of MRTin vitro, T50%, and T90%, may be useful as quality control parameters to which each batch of the ibuprofen SR products...

Effect of Aging on the Dissolution Rate of Nalidixic Acid Tablets

AbstractInvestigation of the dissolution rate profiles of nalidixic acid tablets of three commercial brands was carried out. Using the U.S.P. paddle method, significant inter-brand variations in dissolution rates were found and the tablets did not pass the U.S.P. dissolution test. The dissolution of the tablets was also found to be adversely affected on aging. The observed differences in dissolution rates of the tablets examined were unrelated to their disintegration times. An attempt was made to improve the dissolution rate of nalidixic acid tablets through hydrophilization of nalidixic acid powder and use of tablet excipients with high aqueous solubility were found to yield tablets of good physical qualities which were unaffected on aging.

Effect of Some Formulation Additives on the Oral, Absorption of Indomethacin

AbstractHigher dissolution rates of indomethacin were noted in glycerin-water mixtures, sucrose solutions, sod.-cmc mucilage, from a fabricated capsule containing a buffer and also from drug crystals obtained by precipitation in presence of a physiological surfactant solution. Dogs fed with the drug along with these additives and in the form of a lipid-containing dosage form shoved significantly increased plasma-indomethacin levels. The magnitude of plasma-drug levels from aqueous and oily suspensions and from the prepared capsule was found to be significantly greater than that obtained from the marketed preparation.