Shaikh A.,Institute of Pharmaceutical Education and Research IPER |
Yeole P.G.,Institute of Pharmaceutical Education and Research IPER |
Iyer D.,Institute of Pharmaceutical Education and Research IPER
Research Journal of Pharmaceutical, Biological and Chemical Sciences | Year: 2013
The solubility behaviour of drug is one of most challenging aspect in formulation development. Thus a greater understanding of dissolution & absorption behaviour of drug with low aqueous solubility is required to successfully formulate them into more soluble and hence bioavailable drug product. The current investigation includes formulating solid dispersions of Tinidazole, an antiprotozoal and antiamoebic drug which is characterized by poor solubility and rapid absorption (BCS-2). Thus an attempt was made to prepare stable solid dispersion by improving the solubility and dissolution rate of tinidazole using a mixture of polymers viz: hydroxypropylmethyl cellulose (HPMC), Polaxomer-F-188 (POL), Polyvinyl pyrrolidone (PVP), Polyethylene glycol (PEG) and polymeric surfactants in different proportions as carrier. Solid dispersions of tinidazole were prepared by spray drying technique, melting technique and as physical mixture to conduct a comparative evaluation of the methods that could yield the most stable formulation and then were evaluated for number of analytical parameters. Solid dispersions containing Drug: PEG 6000: Poloxamer 188 as carrier in 1:0.3:0.2 ratios by melting method showed the best result. POL and PEG combination revealed a synergistic effect, on solubility, dissolution and stability of crystalline drug and both crystallization inhibitor (PEG) and wetting agent (poloxamer) in solid dispersion can improve solubility and release profile of tinidazole. The study demonstrates high potential of Melting method for obtaining large surface area and amorphicity of drug using hydrophilic carrier. The solid dispersions were compressed into Fast Dissolving Tablets by incorporating appropriate superdisintegrants.
PubMed | Institute of Pharmaceutical Education and Research IPER
Type: Comparative Study | Journal: Journal of drug targeting | Year: 2010
Mucoadhesive temperature-mediated in situ gel formulations using chitosan and hydroxyl propyl methyl cellulose were used to enhance intranasal (i.n.) delivery of the dopamine D2 agonist ropinirole to the brain. Formulations were tested for gelation time, thermosensitivity, mucoadhesion, in vitro release and permeation, in vitro cytotoxicity, nasal clearance, in vivo bioavailability and brain uptake. In vivo bioavailability and brain uptake of ropinirole were assessed in albino rats following intranasal administration of 99mTc-ropinirole in situ gel, intranasal ropinirole solution and intravenous (i.v.) ropinirole solution. Radiolabeled ropinirole uptake was calculated as a fraction of administered dose. The absolute bioavailabilty of ropinirole from the temperature-mediated in situ gelling nasal formulation was 82%. The AUC (0-480 min) in brain after nasal administration of ropinirole in situ gel was 8.5 times (869 +/- 250% x min/g versus 102 +/- 20% x min/g) that obtained following i.v. administration, this value was also considerably higher (869 +/- 250% x min/g versus 281 +/- 52% x min/g) than that achieved with intranasal ropinirole solution. High brain direct drug transport percentage (DTP; 90.36%) and drug targeting index (DTI) > 1 confirms direct nose to brain transport of the intranasal in situ gel formulation of ropinirole.