ABSTRACT

Dosage forms that can precisely control the release rates and target drugs to a specific body site have made an enormous impact in the formulation and development of novel drug delivery systems. Microspheres form an important part of such novel drug delivery systems. They have varied applications and are prepared using different polymers. Certain problems regarding the drugs like high first pass metabolism, also the bioavailability of the certain drugs varies due to the instability in acidic environment of stomach. Hence, to resolve such problems the drug should be incorporated in the microspheres for sustained release using a suitable polymer. Natural polymer like chitosan gained great interest in pharmaceutical sector because of its advantages like biodegradability, biocompatibility, non-toxicity, non-immunogenicity and low cost. The current research will be oriented towards the formulation and evaluation of polymeric microspheres of different drugs like atorvastatin calcium and amlodipine and investigate the release profile of such drug using the same polymer chitosan.

Keywords: Atorvastatin calcium, Amlodipine, Chitosan, Sodium alginate, Ionotropic gelation method.

ABSTRACT

Potassium chloride is an electrolyte replenisher used in the treatment of hypokalemia. It has a short biological half-life of 1 to 1.5hours. It is a freely soluble drug in the gastric contents while taking it orally. Due to its rapid release, it causes local tissue irritation in the stomach. So, it is considered as an ideal drug for designing an extended release formulation. In the study of commercially prepared batches of Potassium chloride 600mg ER tablets, a few critical factors were identified. They are low hardness, high friability, lower side of assay, coating issues and rapid drug release rate. So the trials were made to overcome the issues by developed the formulation using hydrophobic polymers i.e., Eudragit RSPO and Ethyl cellulose in different ratios and optimized the process using various interrelated variables such as process and granulator parameters to achieve the desired quality of product. Among the various formulation development trials, the results indicated that trial C9 with Eudragit RSPO (11.68%) was the best formulation. Eventually, a reproducibility batch was done to check the similar results. Applying mathematical models, the dissolution profile of C9 formulation follow Korsmeyer-Peppas model and showed similarity factor f2 of 92.76 when compared with the marketed product, Span-K. The stability study was carried out as per ICH guidelines. The stability study indicated there was no significant change in the parameters.

Keywords: Potassium chloride, Eudragit RSPO, Ethyl cellulose, Process optimization.

ABSTRACT

                Carbon nanotubes are the unique tubular structures with nanometer scale for measuring diameter. The nanotubes contain one up to tens and hundreds of concentric shells of carbons with adjacent shell separation. The carbon network of the shells is considered closely related to the honeycomb arrangement of the carbon atoms in graphite sheets. Amazing thermal, mechanical and electronic properties of the nanotubes appear in their structure and also in the graphite-like arrangement of the carbon atoms in shells. The carbon nanotubes have high Young’s modulus and tensile strength, which makes them preferable for composite materials with extended mechanical properties. The carbon nanotubes may exhibit metallic or semiconducting nature depending on their structural parameters. These properties make a way for application of the carbon nanotubes as central elements in electronic devices including field-effect transistors (FET), single-electron transistors and rectifying diodes. These tiny structures also find their way in different applications that touch nearly every field of technology, including aerospace, electronics, medicine, defense, automotive, energy, construction, and even fashion. Carbon nanotubes are also proved to be helpful in drug delivery due to their potent drug targeting property.

Keywords: Nanotechnology, Carbon nanotubes; Synthesis, Electro-chemical properties, Thermal properties, Biosensors.

ABSTRACT

Niosomes are now widely studied as an alternative to liposomes because they alleviate the disadvantages of liposomes, such as chemical instability, variable purity of phospholipids and high cost. The aim of this work is to formulate and evaluate niosomes as carriers for topical delivery of Fluocinonide, as an anti-inflammatory drug, test their stability and improve their anti-inflammatory effect through niosomal encapsulation with objectives of prolonging its action and avoiding its most side effects. Incorporation of Fluocinonide – entrapped niosomes into gelling agents and increasing their concentrations resulted in a marked decrease in amount of drug permeated from the gel through cellulose membrane and rabbit skin. Polymers used as gelling agents are Carbopol 934 and Carboxy Methyl Cellulose sodium (CMC Na). It was found that permeated amount of Fluocinonide decreased with increasing either concentration of Carbopol 934 from 1% to 2% or concentration of CMC Na from 2% to 4%. Amount of Fluocinonide permeated from cellulose membrane are significantly high compared to the amounts permeated across the skin (p<0.01) from the same formulation. On the other hand, there is an increase in the amount of drug permeated from niosomal gels through rabbit skin, compared to that permeated from control drug gels prepared from the same gelling agents (enhancement effect). Stability study was carried out to detect effect of temperature on leakage of drug from the niosomal vesicles and evaluate the percentage of drug retained in the niosomal vesicles and niosomal gel formulations, respectively at different storage temperature (4 ° C, 25 °C and 37 °C). The data obtained were compared statistically using one-way analysis of variance (ANOVA), using Tukey-Krammer Multiple Comparison Test. The anti-inflammatory activity (pharmaco-dynamic properties) of Fluocinonide in its selected formulae was studied using the rat hind paw edema technique and compared with control untreated group. Niosomal gel formula, (F13), containing Span 40: Tween 40: Cholesterol in ratios of 25: 25: 50, consequently and 3% CMC Na is proved to be the most stable and efficient formula for anti - inflammatory activity.

Keywords: Niosomes, Cellulose Membrane; Dorsal Rabbit Skin; Pharmaco-dynamic Properties.

ABSTRACT

The gastrointestinal tract is responsible for the absorption of nutrients and water into the body as well as the elimination of body waste. The small intestine is comprised of a long convoluted tube that is divided into the duodenum, jejunum, and ileum. Its functions consist of absorption of nutrients and water as well as retention and passage of waste materials. The movement of intestinal contents is dependent on the contraction of muscle fibers that are located throughout the intestinal wall. Absorption and movement of the contents are brought about by the activities of the absorptive cells of the mucosa and by coordinated contraction of the smooth muscle cells of the muscularis externa. The movements of the gut involve simultaneous contractions and relaxations of both circular and longitudinal smooth muscle layers at every point along its length. Mechanical recordings of physiological events can be traced back to the kymographic method. Keeping the above findings in view, the present study aims at understanding, whether already established dose of fenoterol, known to induce atrophic changes in muscles is likely to induce any toxic effects on other organ of vital importance or not. Hence, the experiment is designed in such a way to examine the undesirable toxic effects on smooth muscles.

Keywords: Beta –agonist, Fenoterol, Depolarization, Kymograph.

ABSTRACT

The present study was aimed to develop bi-layer tablet of extended release matrix tablets of Niacinamide using various polymers like HPC, PEO AND PVP individually and combination with Amlodipine Besylate Immediate release of using MCC polymers in different proportions. HPC and PEO were selected as hydrophilic and hydrophobic matrix former respectively. The formulated tablets were also compared with a marketed product. The results of the dissolution study indicate that formulation FN4 showed maximum drug release up to 12 hr. that is similar to reference product. In case of formulations containing combination of HPC and PEO, the release of the drug was found to be dependent on the relative proportions of hydrophilic and hydrophobic polymers used in the bi-layer tablet.

Keywords: Niacinamide, Amlodipine, Extended Release, Immediate Release, Bi-layer Tablets.

ABSTRACT

The main objective is to evaluate L-asparaginase production of endophytic fungi isolated from ripened fruit of Capsicum frutescence var US 341. In the present work endophytic fungal strains were screened for production of extra-cellular L-asparaginase, an anti-neoplastic agent used in the chemotherapy of lymphoblastic leukemia. L-Asparaginase activity of endophytic fungi was detected using modified Czapex dok’s medium containing L-asparagine and Phenol red as indicator. In the present study out of 16 fungal isolates, 6 fungal isolates were identified as L-asparaginase positive of which two fungal isolates RFEF-1 and RFEF-2 are identified as Aspergillus sp on their morphological characterization of mycelia, conidiospores and conidia under microscopic observation. The effect of growth parameters on biomass and production of L-asparaginase of these isolates have been characterized. Both isolates showed maximum biomass RFEF-1(2.42gms), RFEF-2(3.03gms) and L-asparaginase production RFEF-1(39.7 IU), RFEF-2(37.86 IU) at 35oC and pH -7.0.

Keywords: Anticancer, L-Asparaginase, antineoplastic agent, Endophytic fungi.

ABSTRACT

Novel drug delivery system is a novel approach to drug delivery that addresses the limitations of the traditional drug delivery systems. Our country has a vast knowledge base of Ayurveda whose potential is only being realized in the recent years. However, the drug delivery system used for administering the herbal medicine to the patient is traditional and out-of-date, resulting in reduced efficacy of the drug. If the novel drug delivery technology is applied in herbal medicine, it may help in increasing the efficacy and reducing the side effects of various herbal compounds and herbs. This is the basic idea behind incorporating novel method of drug delivery in herbal medicines. Thus it is important to integrate novel drug delivery system and Indian Ayurvedic medicines to combat more serious diseases.

Keywords: Microsphere, Controlled Release, Novel drug delivery, Herbal drugs.

ABSTRACT

The aim of the present investigation was to develop oral controlled release matrix tablet formulations of Finasteride using Eudragit and Hydroxypropyl methylcellulose (HPMC) as a hydrophilic release retardant polymer and to study the influence of various formulation factors like proportion of the polymer, polymer viscosity grade, compression force, and release media on the in vitro release characteristics of the drug. The formulations were developed using dry granulation technology. The in vitro release studies were performed using US Pharmacopoeia type 1 apparatus (basket method) in 900 mL of pH 6.8 phosphate buffer at 100 rpm. The release kinetics was analyzed using Korsmeyer–Peppas model. The release profiles found to follow Higuchi’s square root kinetics model irrespective of the polymer ratio and the viscosity grade used. The results in the present investigation confirm that the release rate of the drug from the Eudragit matrices is highly influenced by the drug/Eudragit ratio and viscosity grade of the Eudragit. Also, the effect of compression force and release media was found to be significant on the release profiles of Finasteride from Eudragit matrix tablets. The release mechanism was found to be anomalous non-Fickian diffusion in all the cases. In the present investigation, a series of controlled release formulations of Finasteride were developed with different release rates and duration so that these formulations could further is assessed from the in vivo bioavailability studies. The formulations were found to be stable and reproducible. The results of dissolution studies indicated that the formulation F9 (containing Eudragit as polymer) is the most successful of the study. On increasing polymer ratio a decrease in release rate of the drug was observed after lag time. The optimized formula F9 was best fitted formulation.

Keywords: Finasteride, HPMC, Eudragit, Direct Compression Method.