ABSTRACT
Karaya gum (KG) is one of the least soluble of the gums. It does not dissolve in water to give a clear solution but instead absorbs water rapidly to form viscous colloidal sols. Carboxymethylation of Karaya gum is expected to improve its aqueous solubility and gelling behavior. Another objective of the research is to evaluate the potential of carboxymethylated Karaya gum (CMKG) as drug release modulator (in acidic dissolution medium) when combined with HPMC K15M based polymeric matrices bearing Propranolol HCl. In the present study, KG was carboxymethylated using Williamson Ether synthesis. FTIR spectroscopy confirmed the formation of CMKG. The prepared CMKG was used in conjunction with HPMC K15M as a polymer matrix in the formulation capsule dosage form, using Propranolol HCl as model drug. The filled capsules were then coated with Gelucire 43/01 to convert them into hydrodynamically balanced (HBS) capsule dosage form. Dextrose & fructose were also added to the drug-polymer mix as osmogen to facilitate the drug release. The degree of substitution of CMKG was found to be 0.87. HBS capsule dosage forms remained buoyant on 0.1 HCl for up to 6 hr, the buoyancy was attributed to the Gelucire 43/01 coating around the capsule shell. From the experimentation it was observed that CMKG, when mixed with HPMC K15M at 1:3 ratios, extended the release of model drug from HBS capsule dosage forms in 0.1 HCl. At CMKG: HPMC K15M ratio 2:1, release of Propranolol Hydrochloride from hydrodynamically balanced (HBS) capsules revealed fast drug release in 0.1 HCl. From the observations it is evident that KG is amenable to carboxymethylation to form CMKG. It is also evident that it is advantageous to combine CMKG with HPMC K15M as release modulator to retard the release of Propranolol HCl in acidic dissolution medium.
ABSTRACT
Theophylline has high oral bioavailability and narrow therapeutic index with a biological half-life of 3-4 hrs. Prolonged release dosage forms are designed to complement the pharmacological activity of the medicament in order to achieve the longer duration of action with decreased number of doses administered per day. Matrix tablets were designed using Karaya gum, Guargum and kondagogu gum as sustained release polymers. Wet granulation was employed with 1:1 drug, polymer ratio. The tablets were evaluated for uniformity of weight, hardness friability, swelling index, % drug content, drug dissolution, drug release kinetics and compared. F-2 was found to be better in terms of prolonging the drug release and all the other formulations met the pharmacopoeial requirements for physical tests.
ABSTRACT
The present study involves in the formulation and evaluation of sustained release tablets of Voriconazole (250mg). The objective of the present study was to formulate Voriconazole sustained release tablets by wet granulation method by using natural (Xanthan gum, Karaya gum) and semi synthetic polymers (HPMC K100M). Lactose was used as diluting agent, Magnesium stearate was used as a lubricant and Talc was used as a glident. These sustained release tablets can release the drug up to 12 hours in predetermined rate. The formulated powder blend was evaluated for bulk density, tapped density, compressibility index and angle of repose. The formulated tablets were evaluated for physical characteristics of sustained release tablets such as thickness, hardness, friability, weight variation and drug content. The results of the formulations found to be within the limits specified in official books. The tablets were evaluated for In-vitro drug release studies by using USP type I dissolution test apparatus. The dissolution test was performed in 0.1 N HCL for 2 hr and phosphate buffer pH 6.8 for 10hrs. The in-vitro cumulative drug release profile of all formula-tions F1-F10 at 12 hours showed 84.25% to 99.82% drug release, respectively. From the data it was clear that by increasing the amount of polymer in the formulation the amount of drug release was decreased. Hence, Formulation F9 was the most promising formulation as it gives satisfactory release (99.82%) for 12 hours and F9 found to be the best formulation.
ABSTRACT
Male and female albino rats (Wistar strain) were given single and multiple doses of karaya gum suspended either in peanut oil or mixed with basal diet at different concentrations ranging from 0·5 to 8 g gum/kg body weight. The plant gum did not elicit any overt signs of toxicity or death in both sexes of rats. Daily administration of karaya gum mixed with basal diet at different dose levels (0, 5, 20 and 40 g gum/kg diet) for a period of 90 days showed no adverse effects in male and female rats. The body weight, growth pattern, food and water intake were comparable with those of the normal rats. There were no significant biochemical, or morphological alterations in the vital organs of experimental animals.