Extraction, Purification, and Development of Sublingual Film (SLIT Films) Comprising Cockroach Allergen for Treatment of Allergy.

AIM: Allergy associated with cockroaches are mostly from the American cockroach (Periplaneta americana) and German cockroach (Blattella germanica). The effective and safe treatment for cockroach allergy is Sublingual immunotherapy (SLIT). In this study, SLIT Films containing purified allergen extract of Periplaneta americana were prepared by solvent casting and were evaluated for their efficiency in delivery. METHODOLOGY: Cockroach allergen extract was prepared and purified by ultrafiltration and chromatography. The molecular weight of protein content was identified and estimated by SDS- PAGE and ELISA. SLIT films were developed by the Quality by Design (QbD) approach and were evaluated for allergen- excipient compatibility, swelling index, taste, diffusion, in vitro dissolution, local toxicity, and stability analysis. RESULTS: Cockroach allergen protein extracts (cut-off 25-71KDa) were identified by SDS-PAGE and quantified by indirect ELISA and further selected for sublingual film preparation. The indirect ELISA results show a higher optical density (OD) value compared to crude extract. The weight uniformity and thickness of the film were between 13-18 mg and 0.04-0.06 mm. The disintegration time was found to be less than 1 min. The cumulative percentage release was also found to be satisfactory. The local toxicity study indicated no signs of irritation in the buccal mucosa of rabbits. The optimised F3 film had uniform thickness, faster disintegration and drug content within pharmacopeial limits. Ex vivo study revealed better permeability with 90% release of allergen in 7 minutes. The formulation was also stable at room temperature during the study period. CONCLUSION: SLIT Film containing cockroach allergen from Periplaneta americana was successfully developed and evaluated. SLIT films of cockroach allergen could be more beneficial and convenient for emergency use in patients when compared to subcutaneous immunotherapy. SLIT films provide dose accuracy and are a promising alternative for SCIT and SLIT drops and tablets.

Enhanced Water Dispersibility of Curcumin Encapsulated in Alginate-Polysorbate 80 Nano Particles and Bioavailability in Healthy Human Volunteers.

BACKGROUND: The turmeric (Curcuma longa) plant, a perennial herb of the ginger family, is an agronomic crop in the south and southeast tropical Asia. Turmeric an Indian yellow gold and universal spice is described in Ayurveda, an ancient treatise on longevity and quality life for the treatment of various inflammatory disorders. The oral bioavailability of curcumin is low due to poor aqueous solubility, alkaline instability and speedy elimination. OBJECTIVE: The present study is designed to prepare alginate polysorbate 80 nanoparticles to enhance aqueous solubility/dispersibility, hence bioavailability. METHOD: Curcumin-loaded alginate - polysorbate 80 nanoparticles were prepared by ionotropic gelation technique. RESULTS: The optimized nano particles exhibited higher encapsulation efficiency (95%), particle size of 383 nm and Zeta potential of +200 mV. Formulations exhibited very low dissolution in Simulated Gastric Fluid (SGF) and Simulated Intestinal Fluid (SIF), but the major portion released in SCF which is attributed to the digestibility of alginate in Simulated Colonic Fluid (SCF) under the influence of colonic micro flora. FTIR and DSC observations revealed the successful entrapment of curcumin in alginate polysorbate-80 nanoparticles. The nanoparticles were more spherical, discrete and homogeneous. In healthy human volunteers, the oral bioavailability (AUC) of curcumin increased 5-fold after the consumption of curcumin nanosuspension compared to curcumin suspension. Maximum plasma concentration Cmax- 636 ± 122 ng/ml was observed at tmax- 2h for nanosuspension, whereas Cmax-87.7 ± 17.9ng/ml at tmax- 4h for suspension. CONCLUSION: Curcumin-loaded alginate - polysorbate 80 nanoparticles prepared by ionotropic gelation method, successfully entrapped curcumin. Both curcumin suspension and curcumin nanosuspension were safe and well tolerated and may thus be useful in the prevention or treatment of various inflammatory diseases of mankind.

Formulation and Pharmacokinetic Evaluation of Microcapsules Containing Pravastatin Sodium Using Rats.

Pravastatin Sodium has a cholesterol lowering agent. It has shorter half-life and undergoes first-pass metabolism. Frequent dose is required in case of conventional dosage form. The purpose of the study is to formulate and evaluate microcapsules containing Pravastatin Sodium by complex with cholestyramine resins coated with Eudragit RLPO and Eudragit RSPO polymers for achieving control release. Complexation of drug on resin was carried out by batch method. Microencapsulation was carried out by nonaqueous solvent evaporation method. Pharmacokinetic studies were done by using rats. The intermediate stability studies were carried out on the most satisfactory formulations. FTIR, X-ray diffraction, and DSC spectra of drug, drug-resinates, and polymers revealed no chemical interaction. The % DEE and % yield were observed for formulations of f1 to f7 that were varied from 97.1 ± 0.8 to 98.9 ± 0.5% and 95.0 ± 3.25 to 98.8 ± 7.1%, respectively. Most satisfactory formulation, f6, showed drug release up to 72.6%. No changes in % DEE and % CDR were observed after stability studies. Microcapsules of f6 formulation achieved best performance regarding in vitro drug release and from pharmacokinetic evaluation mean residence time was found to be 6.3 h, thus indicated, Pravastatin Sodium microcapsules were released and absorbed slowly over a prolonged period of time.

In Vitro Intestinal Permeability Studies and Pharmacokinetic Evaluation of Famotidine Microemulsion for Oral Delivery.

The absolute bioavailability of famotidine after oral administration is about 40-45% and absorbance only in the initial part of small intestine may be due to low intestinal permeability. Hence, an olive oil based microemulsion formulation with Tween-80 as surfactant and PEG-400 as cosurfactant was developed by using water titration method with the aim of enhancing the intestinal permeability as well as oral bioavailability. In vitro drug permeation in intestine after 8 h for all formulations varied from 30.42% to 78.39% and most of the formulations showed enhanced permeation compared to pure drug (48.92%). Famotidine microemulsion exhibited the higher absorption and C max⁡ achieved from the optimized famotidine formulation (456.20 ng·h/ml) was higher than the standard (126.80 ng·h/mL). It was found that AUC0-24 h obtained from the optimized famotidine test formulation (3023.5 ng·h/mL) was significantly higher than the standard famotidine (1663.3 ng·h/mL). F-1 demonstrated a longer (6 h) T max⁡ compared with standard drug (2 h) and sustained the release of drug over 24 h. The bioavailability of F-1 formulation was about 1.8-fold higher than that of standard drug. This enhanced bioavailability of famotidine loaded in microemulsion system might be due to increased intestinal permeability.

Anti-obese activity of Butea monosperma (Lam) bark extract in experimentally induced obese rats.

To study the efficacy of ethanolic extract of B. monosperma bark in cafeteria and atherogenic diet fed rats and monosodium glutamate (MSG) obese rats, different doses (200, 400 and 800 mg/kg) of ethanolic extract of B. monosperma bark showed dose dependent decrease in body weight, daily food intake, glucose, lipids, internal organs' weight and fat pad weight in cafeteria and atherogenic diet fed rats and monosodium glutamate obese rats. The results suggested that B. monosperma has significant anti-obese activity.

Sustained ocular delivery of brimonidine tartrate using ion activated in situ gelling system.

The poor bioavailability and therapeutic response exhibited by conventional eye drops due to rapid precorneal elimination of the drug may be overcome by the use of an in situ gelling systems that are instilled as drops into the eye and undergo a sol-to-gel transition in the cul-de-sac which improves patient compliance as the dosage regimen is one drop of the dosage form twice a day. The loss of drug overcomes due to the immediate gel formation between the eye membrane and the drug being entrapped simultaneously in sol-gel transition in the cul de sac. The present work describes the formulation and evaluation of an ophthalmic delivery system of an antiglaucomal agent, brimonidine tartrate based on the concept of ion-activated in situ gelation. Gelrite was used as the gelling agent, which gels in the presence of mono or divalent cations present in the lacrimal fluid. The formulations were evaluated for clarity, pH measurement, gelling capacity, drug content estimation, rheological study, in-vitro diffusion study, antibacterial activity, isotonicity testing, eye irritation testing. In the developed formulations Gelrite Brimonidine-3 (GB3) exhibited sustained release of drug from formulation over a period of 8 hrs thus increasing residence time of the drug, non-irritating with no ocular damage or abnormal clinical signs to the cornea, iris or conjunctiva, stable and sterile. These results demonstrate that the developed system is an alternative to conventional ophthalmic drops, with better patient compliance, and is industrially oriented and economical.

Reduction in drop size of ophthalmic topical drop preparations and the impact of treatment.

In this work we devised a method to create smaller eye drops of the glaucoma medication timolol maleate by altering the dropper tip design and changing the physical properties of the formulation. Most ocular diseases are treated with topical application of eye drops. After instillation of an eye drop, typically, less than 5% of the applied drug penetrates the cornea and reaches the intraocular tissues; the major fraction of the instilled drug is absorbed and enters the systemic circulation. Ophthalmic solutions are available in multidose or single-dose glass/plastic dropper bottles that deliver drops with a volume that ranges from 25 µL to 70 µL (average 40 µL). Because of the low capacity of the precorneal area, the optimal drop volume is about 20 µL; with larger volumes there is the risk of adverse systemic effects due to absorption of the drug via the nasal mucosa. Thus, both from the biopharmaceutical and economic point of view, drops of only 5-15 mL volume should be instilled into the eye. In this present work we devised a method to reduce the size of the drop by inserting a glass capillary tube into the dropper tip and by changing the physical properties of the formulation (by altering the concentration of Tween 80™, i.e., 0.05% and 0.1% of Tween 80™). We measured the drop sizes of the different timolol eye drop formulations available in the market and estimated the yearly cost of the medications. Our timolol maleate formulation with 0.1% concentration of Tween 80™ delivered through the dropper tip with the inserted glass capillary was shown to be better than the other formulations available in the market in terms of ability to deliver smaller drops, meaning that each bottle would last longer and that the yearly cost of treatment would be lower.

Design and evaluation of a metronidazole central core matrix tablet.

In this paper, a study of different concentration of HPMC K 15 M exerts influence on the drug release process from a new controlled drug delivery system has been realized in order to obtain a constant release rate during a prolonged period of time, for a programmed drug release. The drug release profiles obtained for the different batches have shown an interesting relationship between the particle size of the channeling agent used and the length of different operational periods.