In vitro Release kinetics and Bio availability of Layered Matrix tablets of Diclofenac Sodium

Controlled release tablets having near zero-order release of diclofenac sodium water soluble drug were prepared using guar gum (GG) in matrix core and Hydroxy Propyl Cellulose (HPC), Hydroxy Propyl Methyl Cellulose (HPMCK4M) and Sodium Carboxy Methyl Cellulose (Na CMC) as barrier layers. The optimum ratio of drug: guar gum was found to be 1:1, anionic GG in the matrix core and anionic Na CMC as barrier layers resulted in near zero order release of diclofenac sodium. Different dissolution models were applied to drug release data in order to evaluate release mechanisms and kinetics. The nature of drug release from matrix tablets and layered matrix tablets followed non-Fickian diffusion and super case II mechanism respectively. Mean dissolution time (MDT) for the formulations MT-GG and MLT-06 were found to be 3.65h and 16.57h, while Dissolution Efficiency (DE8%) decreases, indicating that the release of drug is slower from layered matrix tablets. On the basis of in vitro release data, MLT-06 was subjected to bioavailability studies. The in-vivo characterization of diclofenac sodium in human volunteers from formulation MLT-06 showed delayed Tmax unaltered bio availability indicating a slow and controlled release of the drug from layered matrix tablets.Keywords: Diclofenac sodium, Matrix and layered matrix tablets, Controlled released

FORMULATION AND EVALUATION OF BILAYERED FELODIPINE TRANSDERMAL PATCHES: IN VITRO AND EX VIVO CHARACTERIZATION

Objective: Felodipine (FD) is an effective Biopharmaceutics Classification System Class II calcium channel blocker mainly used in the management of hypertension and angina pectoris. It has poor solubility and low oral bioavailability (15%). To overcome these disadvantages and to maintain constant plasma concentration for maximum therapeutic activity, there is a need to design an alternative route, that is, transdermal route. The pharmacokinetic parameters make FD a suitable candidate for transdermal delivery. The present investigation consists of the study of in vitro and ex vivo skin flux of FD from bilayered transdermal patches. Methods: The patches were fabricated by solvent casting method using hydrophilic and hydrophobic polymer with different composition. Tween 80 incorporated as solubilizer, polyethylene glycol 600 as plasticizer, menthol, eucalyptus oil, and lemongrass oil used as permeation enhancers, respectively. The prepared transdermal drug delivery system was extensively evaluated for in vitro release, ex vivo permeation through pig ear skin, moisture content, moisture absorption, water vapor transmission, and mechanical properties. The physicochemical interaction between FD and polymers was investigated by Fourier-transform infrared (FTIR) spectroscopy. Results: All the formulations exhibited satisfactory physicochemical and mechanical characteristics. A flux of 35.2 μg/cm2 h, 27.9 μg/cm2 h, and 25.25 μg/cm2 h was achieved for optimized formulations containing lemongrass oil, eucalyptus oil, and menthol, respectively, permeation enhances. Values of tensile strength (0.0652±0.034 kg/mm²) and elongation at break (0.8749±0.0.0029% mm²) revealed that formulation F9 was strong but not brittle. Drug and excipients compatibility studies showed no evidence of interaction between the active ingredient and polymers. Conclusion: Bilayered FD transdermal patches could be prepared with required flux and suitable mechanical properties

INFLUENCE OF HYDROXYPROPYL-β-CYCLODEXTRIN ON REPAGLINIDE RELEASE FROM SUSTAINED RELEASE BIOADHESIVE BUCCAL TABLETS

Objective: The purpose of this investigation was to study the influence of cyclodextrin complexation on development of sustained release bio-adhesive repaglinide tablets for buccal delivery. Methods: Based on preliminary phase solubility studies, solid complexes prepared by freeze-drying method in 1:1 molar ratio were selected and characterized by Fourier transform infrared spectroscopy to corroborate the fact of complex formation. The sustained release repaglinide tablets were produced by direct compression and this drug or complexed –loaded hydrophilic matrices using HPMC, Sodium CMC and Carbopol as muco-adhesive polymers were assessed for in vitro bioadhesion strength, in vitro release modulation, surface pH, % moisture absorption and ex vivo permeation through porcine buccal membrane. Results: When the drug was incorporated as repaglinide-Hydroxypropyl-β-Cyclodextrin (HP-β-CD) freeze-dried product, total amount of drug permeated from the tablet through epithelium in about 12 hrs, displaying a constant release regimen after a transient period. The effect of HP-β-CD incorporation on the release mechanism was rationalized on the basis of the interplay of different physical phenomena: erosion and swelling of the tablet, drug dissolution, and complex formation. Formulation F10 showed % moisture absorption of 23.46 for 4hrs, surface pH 6.9±0.015, Peak detachment force 3.65±0.18 N, Work of adhesion 1.12±0.10 mJ, and in vitro drug release 98.31% in 6h. The feasibility of buccal administration of repaglinide was assessed by permeation experiments on excised mucosa of pig. The ex vivo permeation studies demonstrated that the matrix tablets containing repaglinide–HP-β-CD (F10) solid complex exhibited significantly higher drug permeation (92.18 % for 12hrs) compared to all of the other formulations tested, which could be attributed to both, the presence of the polymers, and the drug-cyclodextrin complexation. The flux was found to be increased by 1.12-1.37 folds with a permeability coefficient of 0.017-0.018. Conclusion: The results demonstrate that the formulations with inclusion complexes afford high utility as a trans-mucosal drug delivery system for improved drug release and permeability.   KEY WORDS: Repaglinide, Freeze drying, HP-β-CD complexation, Bioadhesion, Ex-vivo permeation, Solubility &nbsp

Development of floating matrix tablets of Ofloxacin and Ornidazole in combined dosage form: in vitro and in vivo evaluation in healthy human volunteers

Ofloxacin (OFX) is a synthetic broad spectrum analog of second generation fluoroquinolone antibiotic. It is used for the treatment of urinary tract, prostate, skin, urinary and respiratory tract infections. Ornidazole (ORN) is a nitroimidazole derivative. It is used in the treatment of bacterial vaginosis, trichomoniasis, amoebiasis, giardiasis and infections due to anaerobic bacteria. These drugs are highly soluble in acidic media and precipitates in alkaline media thereby losing its solubility. Hence we attempted to develop a gastro retentive floating matrix type drug delivery system for Ofloxacin and Ornidazole in combined dosage form with hydroxyl propyl methyl cellulose (HPMC) K15M, HPMC K100M and polyethylene oxide 18NF (PEO). The physicochemical compatibility of the drug and the polymers was studied by infrared spectroscopy and differential scanning calorimetry. The results suggested no physicochemical incompatibility between the drug and the polymers. The prepared floating drug delivery systems were evaluated for physicochemical characteristics, mainly in vitro release and in vivo residence time by radiographic studies. The best formulation (F2) was selected based on in vitro release and physicochemical characteristics and used in vivo radiographic studies by incorporating BaSO4. These studies revealed that tablets 300 ± 30 minutes in healthy human volunteers in fasting state and indicated that the gastric retention was increased by floating principle. By fitting the data into zero order, first order and Higuchi models, it was concluded that drug release from matrix tablets followed Higuchi model and the mechanism of drug release was diffusion mediated. Based on the physical evaluation, in vitro drug release and in vivo characteristics, it was concluded that for potential therapeutic use, suitable for the development of a floating drug delivery system of Ofloxacin and Ornidazole in combined dosage form

Development of floating matrix tablets of Ofloxacin and Ornidazole in combined dosage form: in vitro and in vivo evaluation in healthy human volunteers

Ofloxacin (OFX) is a synthetic broad spectrum analog of second generation fluoroquinolone antibiotic. It is used for the treatment of urinary tract, prostate, skin, urinary and respiratory tract infections. Ornidazole (ORN) is a nitroimidazole derivative. It is used in the treatment of bacterial vaginosis, trichomoniasis, amoebiasis, giardiasis and infections due to anaerobic bacteria. These drugs are highly soluble in acidic media and precipitates in alkaline media thereby losing its solubility. Hence we attempted to develop a gastro retentive floating matrix type drug delivery system for Ofloxacin and Ornidazole in combined dosage form with hydroxyl propyl methyl cellulose (HPMC) K15M, HPMC K100M and polyethylene oxide 18NF (PEO). The physicochemical compatibility of the drug and the polymers was studied by infrared spectroscopy and differential scanning calorimetry. The results suggested no physicochemical incompatibility between the drug and the polymers. The prepared floating drug delivery systems were evaluated for physicochemical characteristics, mainly in vitro release and in vivo residence time by radiographic studies. The best formulation (F2) was selected based on in vitro release and physicochemical characteristics and used in vivo radiographic studies by incorporating BaSO4. These studies revealed that tablets 300 ± 30 minutes in healthy human volunteers in fasting state and indicated that the gastric retention was increased by floating principle. By fitting the data into zero order, first order and Higuchi models, it was concluded that drug release from matrix tablets followed Higuchi model and the mechanism of drug release was diffusion mediated. Based on the physical evaluation, in vitro drug release and in vivo characteristics, it was concluded that for potential therapeutic use, suitable for the development of a floating drug delivery system of Ofloxacin and Ornidazole in combined dosage form

<b>Cosmeceutical applications of Aloe gel</b>

322-327Aloe vera is considered as a cosmeceutical herb i. e. a blend of cosmetic and pharmaceutical product. The gel from its leaves finds a wide range of cosmetic and therapeutic applications which include anti-wrinkle creams, moisturizers, sunscreens, haircare products and wound healing, treatment of burns, frostbite, inflammation, diabetes and cancer. It is also used as protective against radiation exposure and as antimicrobial agent. The present article discusses the chemistry, cosmetic and medicinal applications of Aloe gel and its adverse effects