The objective of this study was to prepare a nanoparticulate formulation of simvastatin (SV) for improving oral bioavailability and sustaining the drug release while investigating the effect of various formulation parameters on characteristics of nanoparticles. Nanoparticles containing SV were prepared by a modified emulsification solvent evaporation technique using a biodegradable polymer, poly(d,l-lactide-coglycolide) (PLGA) as a sustained release carrier. The effect of various formulation parameters such as drug polymer ratios (SV:PLGA, 1:4 to 1:1), organic solvents (methanol/dichloromethane), and surfactants (PVA/polysorbate-80) in a fixed concentration (0.5%, w/v) were studied for particle size, drug loading, and entrapment efficiency. Nanoparticles were characterized by differential scanning calorimetry (DSC) and their shapes were observed by scanning electron microscopy (SEM). An aqueous solubility study indicated that the dissolution rates were remarkably increased for nanoparticles compared with the drug alone. The in vitro drug release study of the nanoparticles showed a biphasic release pattern: one initial burst release of 40.56% in the first 4 h which can be helpful to improve the penetration of drug followed by a second slow-release phase (extended release) consistent with a Higuchi diffusion mechanism. The hypolipidemic activity of nanoparticles was determined in comparison with SV in male Wistar rats for changes in total cholesterol (CH) and triglyceride (TG) levels in blood. Nanoparticles showed a significantly better in vivo performance than SV in reducing total CH and TG levels which is primarily attributed to the improved solubility and dissolution of nanoparticles. Together, these results indicate that nanoparticulate formulations are ideal carriers for oral administration of SV having great potential to improve the oral bioavailability and sustain the drug release, thereby minimizing the dose-dependent adverse effects and maximizing the patient's compliance.

Nasal in situ gel of sodium cromoglycate was prepared for sustained release and improvement of drug bioavailability. Carbopol 940 was used as a key ingredient which gives pH-induced sol to gel conversion of the formulations. Different formulations were prepared by varying the concentrations of carbopol 940 and different grades of Hydroxyl Propyl Methyl Cellulose (HPMC K100, HPMC K4M and HPMC K15M). These formulations were evaluated for parameters like pH, drug content, viscosity, gel strength, in vitro drug release and drug excipient compatibility. In this study, the release profile depends on the concentration of carbopol 940 and grade HPMC. A 3 ² factorial was applied to check the effect of varying the concentration of carbopol 940 (X ₁ ) and different grades of HPMC (X ₂ ) on the dependent variable i.e. viscosity, mucoadhesive strength, cumulative percentage drug released in 1 h (Q ₁ ), 4 h (Q ₄ ) and 8 h (Q ₈ ) as dependent variables . In vitro release data was fitted to various models to ascertain the kinetic of drug release. Regression analysis and analysis of variance were performed for dependent variables. The results of the F-statistics were used to select the most appropriate model. Formulation F6 was considered optimum which contained carbopol 940 (0.75%) and HPMC K4M (0.50%) and was more similar to the theoretical predicted dissolution profile (f₂ =70.99). The studies indicate that the formulation was effective in providing in vitro release, in vitro permeation of drug and the mucoadhesion which increases the residence time of drug.

The overall objective of this present investigation was to determine the synergistic potentiality of Landolphia owariensis latex (LOL) and Eudragit^® L-100 as hydrophobic polymeric agents in ensuring controlled drug release for possible colon-targeted delivery of metronidazole. Metronidazole granules were prepared by the wet granulation method and manually encapsulated. The entire capsule surface was first coated with Eudragit^® L-100 (primary coating). Secondly half (50%) or five-sixth (5/6 or 83%) of the capsule surface was coated atop the primary coating with LOL (secondary coating). Two different granule size fractions were isolated and compared. Parallel gradient in vitro drug release studies were carried out in media of pH 1.2, 6.8 and 7.4, respectively. The dissolution data were subjected to kinetic treatment. Results showed that the least quantity of drug release took place at pH 1.2 followed by pH 6.8, with greatest drug release taking place at pH 7.4. Capsule surface coated with LOL significantly (P<0.05) affected drug release and time of release. Matrix former (binder) concentration had no significant (P<0.05) effect on drug release, but particle size did. More than one drug release mechanisms were operational and most capsules with 50% surface coated with LOL recorded higher Dissolution efficiency (DE) but lower Mean dissolution time (MDT) than those of 83%. In conclusion, the use of Eudragit^® L-100 and LOL as primary and secondary capsule coatings respectively have demonstrated competence in controlling drug release and thus may hold promise at preferentially targeting metronidazole to the colon against amebic diseases.

The aim of this study was to develop a fast releasing oral polymeric film, prepared using the solvent casting method, with good mechanical properties, instant disintegration and dissolution, an acceptable taste in the oral cavity. Levocetirizine dihydrochloride, an antihistamine, was incorporated to relieve the symptoms of allergic rhinitis. Four batches of films with drug were prepared using different combinations of polymers and plasticizers Eudragit^; EPO, HPMC E 5 LV, and PVA were the selected polymers. Glycerin, dibutyl phthalate, propylene glycol, and PEG 400 were the selected plasticizers. The resultant films were evaluated for weight variation, assay, content uniformity, folding endurance, thickness, tensile strength, percent elongation, surface pH, in vitro disintegration and in vitro dissolution. The formulations from the preliminary trial were analyzed using Taguchi OA experimental design, which was applied to optimize the type of polymers, concentration of polymers, plasticizer, and sweetener based on their disintegration data at three different levels. The optimized films disintegrated in less than 30s, releasing 70-90% of drug within 2 mins. The percentage release varied with the type of polymer and concentration of polymer. The films made with EPO released 96% of drug in 2 mins, which was the best release among all.

Euryale ferox (family Nymphaeaceae), a plant belonging to the water lily family, grows in water ponds and remains buoyant on water surface. Similarly, its edible seeds also remain afloat in a wide variety of liquid mediums. Thus, the purpose of this study was to develop non-effervescent floating matrix tablets using E. ferox seeds powder (EFSP). Different matrix tablets were prepared using hydroxy propyl methyl cellulose (HPMC) K4M, ciprofloxacin HCl and EFSP. The effects of various formulation variables were investigated on in vitro drug release and in vitro floating behavior of the matrix tablets. With increase in EFSP proportion in the matrix tablets, improvement in buoyancy was observed. The floating behavior of tablets was also found to be dependent on particle size of EFSP. Further, surface morphology of different particle sizes of EFSP was studied with Scanning Electron Microscope images. Drug release from matrix tablets was reduced in the presence of EFSP particles. Most of the formulations were best fitted with Korsmeyer-Peppas and zero-order release kinetics. The value of n was found to be between 0.45 and 0.89, which indicates non-fickian drug transport. Thus, non-effervescent floating behavior can be successfully achieved by using EFSP in HPMC K4M based matrix tablets.

The purpose of the present work is to design and evaluate extended release matrix tablets of metoprolol succinate to reduce the dosing frequency and to improve patient compliance. The matrix tablets were prepared by the combination of hydrophilic and hydrophobic polymers, using methocel 10000 Cps in combination with ethyl cellulose 7 Cps, Eudragit^® RS100, Eudragit^® S100, and Eudragit^® L100.The tablets were prepared by direct compression technique. Prepared formulations were evaluated for various parameters like weight variation, thickness, hardness, friability, and % drug content. Tablets were subjected to in vitro drug release studies. The formulations containing methocel 10000 Cps, Eudragit^® L100 showed good release retardation. All the prepared formulations showed first-order release kinetics with matrix diffusion mechanism of release. The formulation containing 52.06% w/w of methocel 10000 Cps, 8.75% Eudragit^® L100 offered the required release rate according to USP Pharmacopoeial guidelines. The combination of hydrophilic and hydrophobic polymers can effectively control the drug release for freely water-soluble drugs in case of extended release formulations which are the upcoming dosage forms for patient compliance in all aspects.

The aim of the present investigation was to formulate mouth dissolving tablets of olanzapine, an anti-psychotic drug. Mouth dissolving tablets (MDT) of Olanzapine were prepared with the addition of different superdisintegrants, namely, crospovidone, croscarmellose sodium, and sodium starch glycolate. Each of these superdisintegrants was used in concentrations of 2% w/w, 4% w/w, 6% w/w, and 8% w/w. Formulation with 4% w/w crospovidone showed minimum disintegration time (<30 seconds). Furthermore, increasing the concentration of the superdisintegrants did not decrease the disintegration time (DT) significantly, so the same formulation was selected to incorporate the effervescent agent to reduce the disintegration time further. The formulation was optimized successfully with sodium bicarbonate and citric acid (monohydrate) as the effervescent agent, with 4% of crospovidone, thereby reducing the disintegration time to 10 seconds. The prepared batches were evaluated for organoleptic properties, hardness, friability, weight variation, in-vitro disintegration time, in-vitro dispersion time, wetting time, in-vitro drug release studies, and stability studies. The drug-excipient interaction was studied by Fourier transform infrared spectroscopy (FTIR) studies. The optimized formulation showed minimum disintegration time (10 seconds) and an almost complete release of the drug within five minutes. Finally it was concluded that the MDT of Olanzapine could be successfully formulated by adding superdisintegrants and an effervescent agent, with improved patient compliance.

Effective management of various ocular infective diseases using levofloxacin eye drops remains challenging owing to poor ocular drug bioavailability. Hence, this study aimed to develop and evaluate nanosphere colloidal suspension-containing levofloxacin as potential ophthalmic drug delivery system. The levofloxacin-loaded chitosan nanoparticles were prepared by ionic gelation of chitosan with tripolyphosphate anions. The nanoparticles were characterized by scanning electron microscopy, zeta potential analyzer, differential scanning calorimetry, and fourier transform infrared spectroscopy. All the prepared formulations resulted in nano-range size particles (317-501 nm) and displayed spherical smooth morphology with zeta potential (+37.2 to +43.5 mV). The encapsulation efficiency and loading capacity were 65-83% and 15-25%, respectively. The levofloxacin-loaded chitosan nanoparticles displayed more crystallinity than levofloxacin. The in vitro diffusion profile of levofloxacin from the nanoparticles showed a sustained release of the drug over a period of 20 h. Kinetic release profiles of levofloxacin from nanoparticles appeared to fit best with Higuchi model with zero order and the non-Fickian diffusion was superior phenomenon. Thus, the results suggest that levofloxacin-loaded chitosan nanoparticle suspension appears to be promising enough for effective management of ocular infections.

This study describes the formulation and characterization of topical gel of chrysophanol containing carbopol as gel base. The partition of drug between skin and the hydrogel matrix was considered to play an important role in the permeation process. The effect of three levels of carbopol and three different permeation enhancers on chrysophanol permeability was determined in vitro. Each formulation was characterized in terms of viscosity, pH, extrudability, spreadability, homogenicity, drug content, skin irritation, stability, and drug release studies. The gel consisting of 1% carbopol as gel base and 15% dimethylsulfoxide showed superior physicochemical and permeability properties and it was ranked best. Reports of pharmacokinetic parameters showed that the drug release is controlled by both diffusion and relaxation processes.

The aim of this study is to formulate a toothpaste containing povidone-iodine (PVP-I) and evaluate its chemical stability. PVP-I was incorporated into toothpastes from different trademarks and a new toothpaste formulation containing PVP-I was also prepared. The obtained toothpastes were coded as F1, F2, F3 and F4, respectively. Chemical stability of PVP-I in the formulations (according to the USP method) was checked over a period of 7 weeks. Color, pH and smell of the obtained toothpaste formulations were evaluated. PVP-I in F1, F2 and F3 toothpastes was stable over the 7-week period in the first two formulations and for only 4 weeks in the last one. However, PVP-I was only stable for a period of 3 weeks when it was the only active ingredient as in F4. The pH of the formulations remained constant for the entire study period for all formulations. No changes in viscosity, smell or color of all the toothpaste formulations were observed. The compounding of PVP-I toothpaste in order to achieve oral hygiene can be achieved successfully. Attention should be made by practicing pharmacists with regard to the exact expiry dates of the obtained formulations.