Transdermal Anti-Inflammatory Delivery for Solid Lipid Nanoparticles of Ketoprofen by Microwave-Assisted Microemulsion.

PURPOSE: To prepare solid lipid nanopaticles (SLNs) of Ketoprofen (KP) using microwave method. Ketoprofen (KP) is 2-(3-benzolphenyl) propionic acid with anti-inflammatory, analgesic and antipyretic property. The drug has short half-life of 120 mins. It belongs to BCS Class II drug. Gastric irritation is a major limitation for delivery because of acidic nature of the drug. Development of solid lipid nanoparticles with its transdermal drug delivery was the aim of present work. METHODS: Microwave-assisted microemulsion technique was used for the development of solid lipid nanoparticles. Stearic acid was used as lipid and tween 80 was used as surfactant. By varying the type of lipid and input energy watt, batches were formulated. SLNs were evaluated for zeta potential, drug entrapment, particle size and in-vitro drug release. Crystallinity behaviour was determined by differential scanning calorimetry and powder X-ray diffraction. Anti-inflammatory activity was evaluated for batch M4 of SLNs. The gel was prepared for M4 batch. It was evaluated for viscosity, pH, drug content, in-vitro and ex-vivo diffusion study. RESULTS: SLN were developed successfully. Based on the size, entrapment efficiency, stability and drug release, batch M4 was selected. SLNs showed 74.8% entrapment efficiency. Forty-fold improvement was observed in the solubility. The particle size was of 682.9 nm and average size of 1047 nm. PDI was 0.685. Zeta potential was -29.5 mV. M4 SLNs batch of gel showed burst release followed by a controlled release for 8 hrs in in-vitro drug release. CONCLUSION: SLNs were successfully prepared by Microwave-assisted microemulsion technique. SLNs with anti-inflammatory activity was successfully developed with its transdermal delivery.

Optimization of Microemulgel for Tizanidine Hydrochloride.

BACKGROUND: Tizanidine hydrochloride acts centrally as a muscle relaxant. It is used for the treatment of painful muscle spasm, spasticity associated with multiple sclerosis or spinal cord injury and treatment of muscle spasticity in spinal cord disease. Tizanidine hydrochloride belongs to BCS class II. It has low oral bioavailability and short halflife. Incorporating this drug in microemulgel is an excellent way to overcome problems associated with the drug. OBJECTIVES: Present research work was aimed to develop and optimize a microemulsion based gel system for tizanidine hydrochloride. METHODS: Screening of oil, surfactant and co-surfactant was carried out. Ternary phase diagram was constructed to obtain concentration range of components. The prepared microemulsion was evaluated for pH, globule size, zeta potential, conductivity, density and viscosity. 32 level factorial design was applied to study the effect of concentration of carbopol 934 and HPMC K15M on % cumulative drug release and viscosity of microemulgel using software Design Expert. Microemulgel was evaluated for pH, spreadability, viscosity, syneresis, drug content, bioadhesive strength, in-vitro as well as ex-vivo diffusion study. RESULTS: Microemulsion was prepared by using isopropyl myristate as oil, tween 80 as a surfactant and transcutol P as cosurfactant. Largest transparent microemulsion region was found with Smix ratio of 1:1. FE-SEM showed globule size 28µm for batch B1 and zeta potential was -1.27mV indicating good stability of the microemulsion. Optimised batch was F6 which showed 92% drug release within 8 hours. It followed the Korsmeyer-Peppas model. CONCLUSION: A stable, effective and elegant microemulgel formulation, exhibiting good in-vitro and ex-vivo drug release was formulated.

Development of Microemulsion Based Nabumetone Transdermal Delivery for Treatment of Arthritis.

BACKGROUND: Nabumetone is biopharmaceutics classification system (BCS) class II drug, widely used in the treatment of osteoarthritis and rheumatoid arthritis. The most frequently reported adverse reactions for the drug involve disturbance in gastrointestinal tract, diarrhea, dyspepsia and abdominal pain. Microemulgel has advantages of microemulsion for improving solubility for hydrophobic drug. Patent literature had shown that the work for drug has been carried on spray chilling, enteric coated tablet, and topical formulation which gave an idea for present research work for the development of transdermal delivery. OBJECTIVE: The objective of the present research work was to optimize transdermal microemulgel delivery for Nabumetone for the treatment of arthritis. METHODS: Oil, surfactant and co-surfactant were selected based on solubility study of the drug. Gelling agents used were Carbopol 934 and HPMC K100M. Optimization was carried out using 32 factorial design. Characterization and evaluation were carried out for microemulsion and microemulsion based gel. RESULTS: Field emission-scanning electron microscopy (FE-SEM) study of the microemulsion revealed globules of 50-200 nm size. Zeta potential -9.50 mV indicated good stability of microemulsion. Globule size measured by dynamic light scattering (zetasizer) was 160nm. Design expert gave optimized batch as F7 which contain 0.2% w/w drug, 4.3% w/w liquid paraffin, 0.71% w/w tween 80, 0.35% w/w propylene glycol, 0.124% w/w Carbopol 934, 0.187% w/w HPMC K100M and 11.68% w/w water. In-vitro diffusion study for F7 batch showed 99.16±2.10 % drug release through egg membrane and 99.15±2.73% drug release in ex-vivo study. CONCLUSION: Nabumetone microemulgel exhibiting good in-vitro and ex-vivo controlled drug release was optimized.

Physicochemical characterization and solubility enhancement studies of allopurinol solid dispersions / Caracterização físico-química e estudos de solubilidade de melhoria de dispersões sólidas de alopurinol

Allopurinol is a commonly used drug in the treatment of chronic gout or hyperuricaemia associated with treatment of diuretic conditions. One of the major problems with the drug is that it is practically insoluble in water, which results in poor bioavailability after oral administration. In the present study, solid dispersions of allopurinol were prepared by solvent evaporation, kneading method, co-precipitation method, co-grinding method and closed melting methods to increase its water solubility. Hydrophilic carriers such as polyvinylpyrrolidone, polyethylene glycol 6000 were used in the ratio of 1:1, 1:2 and 1:4 (drug to carrier ratio). The aqueous solubility of allopurinol was favored by the presence of both polymers. These new formulations were characterized in the liquid state by phase solubility studies and in the solid state by differential scanning calorimetry, powder X-ray diffraction, UV and Fourier Transform Infrared spectroscopy. Solid state characterizations indicated that allopurinol was present as an amorphous material and entrapped in polymer matrix. In contrast to the very slow dissolution rate of pure allopurinol, the dispersion of the drug in the polymers considerably enhanced the dissolution rate. Solid dispersion prepared with polyvinylpyrrolidone showed highest improvement in wettability and dissolution rate of allopurinol. Mathematical modeling of in vitro dissolution data indicated the best fitting with Korsemeyer-Peppas model and the drug release kinetics primarily as Non-Fickian diffusion. Therefore, the present study showed that polyvinylpyrrolidone and polyethylene glycol 6000 have a significant solubilizing effect on allopurinol.

Alopurinol é fármaco comumente utilizado no tratamento de gota crônica ou hiperuricemia associada com o tratamento em condições diuréticas. Um dos maiores problemas com o fármaco é que este é praticamente insolúvel em água, o que resulta em baixa biodisponibilidade na administração oral. No presente estudo, dispersões sólidas de alopurinol foram preparadas pela evaporação do solvente, pelos métodos de amassamento, de coprecipitação, de comoagem e fusão fechada para aumentar sua solubilidade em água. Transportadores hidrofílicos, como polivinilpirrolidona, polietilenoglicol 6000 foram utilizados nas proporções de 1:1. 1:2 e 1:4 (fármaco: transportador). A solubilidade aquosa do alopurinol foi favorecida pela presença de ambos os polímeros. Estas novas formulações forma caracterizadas no estado líquido pelos estudos de solubilidade de fase e no estado sólido pela calorimetria diferencial de varredura, difração de Raio-X, espectroscopia de UV e de IV com transformada de Fourier. As caracterizações do estado sólido indicaram que o alopurinol estava presente como material amorfo e embebido em matriz polimérica. Ao contrário da velocidade de dissolução lenta do alopurinol puro, a dispersão do fármaco nos polímeros aumentou consideravelmente a taxa de dissolução. A dispersão sólida preparada com polivinilpirrolidona mostrou as maiores melhorias na molhabilidade e taxa de dissolução do alopurinol. A modelagem matemática dos dados da dissolução in vitro indicou o melhor ajuste ao modelo de Korsemeyer-Peppas e a cinética de liberação do fármaco primariamente como difusão não-Fickiana. Assim, o presente estudo mostrou que a polivinilpirrolidona e o polietilenoglicol 6000 têm efeito significativo na solubilização do alopurinol.

Pulsatile multiparticulate drug delivery system for metoprolol succinate.

Cardiovascular diseases and their treatment pose a great challenge. Many instances of cardiovascular disease occur in the early morning hours. Hence, the objective of this study was to develop a time-controlled release formulation of metoprolol succinate based on a pulsatile multiparticulate (pellets) drug delivery system. The formulation was intended to be administered in the evening at 22:00 hours to evaluate symptoms of cardiovascular disease that are experienced in the early morning hours (from 04:00 to 06:00). Drug layering followed by a swelling layer and finally by an insoluble coat application was done using a Sanmour fluid bed processor. Metoprolol succinate layered on sugar pellets (74% w/w) layered with 20% (w/w) ion doshion resin P-547 and coated with 15% (w/w) ethocel with the addition of 20% castor oil showed a lag time of 4 h and was then followed a sigmoidal release pattern with more than 95% drug having been released by the 10(th) h.