Medium Molecular Weight Chitosan as a Carrier for Delivery of Lincomycin Hydrochloride from Intra-pocket Dental Film: Design, Development, in vitro and ex vivo Characterization.

The purpose of investigation is to find out the potential of Medium Molecular Weight Chitosan (MMWCH) loaded with Lincomycin Hydrochloride (LNC) having pKa 7.6 and log p value 0.20 for treatment of periodontitis and gingivitis, prepared by using solvent casting technology in form of intra pocket dental film. Four sets of formulation were prepared and each set comprises of four formulations each. The formulations were evaluated for drug content uniformity, weight uniformity, thickness of patch, surface pH, moisture loss, swelling index, water vapor transmission rate, static in vitro release studies using diffusion cell, ex vivo flux study using diffusion cell by help of excised gum lining of goat, release kinetics and Akaike Information Criteria; goodness of fit (AIC) value determination. Excipient drug interaction was carried out by using Fourier Transform Infrared spectroscopy (FTIR), and by Thermo gravimetric Analysis (TGA)/Differential thermal analysis (DTA)/Derivative thermo gravimetric analysis (DTG) and this suggests that there is no drug excipient interaction occurs. The drug release studies show the sustained release without any burst effect for consecutive 5 days. Formulation R1, R2, R7, R8, R9, R10, R13 and R14 and follows the zero order release pattern and formulation R3, R4, R5, R6, R11, R12, R15 and R16 follows the Higuchi model because they have lower AIC value and higher r2 value. Formulation ER17, ER18, ER19 and ER20 is having the average flux of 1.0, 1.48, 1.35 and 1.45 mg/cm2 hr-1 respectively, and when compared statistically student’s paired t-test these all formulations are significantly different from each other.

Development of Enteric Coated Sustained Release Matrix Tablets of Sertraline Hydrochloride.

The aim of the present investigation is to develop enteric coated sustained release matrix tablets of Sertraline hydrochloride (STH) using HPMC K4M and Carbopol-971 as drug release retardants and cellulose acetate phthalate (CAP) as an enteric coat polymer. The tablets were prepared by direct compression process and evaluated for various physico-chemical/mechanical parameters. Among the two release retardants, HPMC K4M was selected based on controlling the STH release during dissolution. The effect of different fillers like microcrystalline cellulose (MCC), di calcium phosphate (DCP), spray dried lactose with maize starch (SDL) and pre gelatinized starch (PGS), on STH release was also studied. The percent of STH released at the end of dissolution with different fillers is in the order of SDL > MCC > DCP > PGS. The tablets containing 15% w/w of HPMC K4M & MCC as filler with 5% coating weight gain (1% v/v glycerine in 5%w/v CAP solution) gave a STH release of less than 10% in 0.1N HCl (pH 1.2) for 2 h and a sustained release of STH over a period of 12 h (99.17±0.54%) in pH 6.8 phosphate buffer and fulfilled the regulatory requirements. The dissolution data was also evaluated for drug release kinetics and mechanisms.

Liberación de pravastatina sódica formulada en matrices poliméricas a base de Quitosan/Pluronic F ̶ 127 / Release of pravastine sodium formulated in polymer chitosan/pluronic f-127 matrices

Introducción: el desarrollo de medicamentos transdérmicos manifiesta gran interés en los últimos años debido a las ventajas que ofrece; sin embargo, muchos de los sistemas desarrollados utilizan componentes solubles lo cual podría llevar a una ineficacia terapéutica si la matriz polimérica del sistema se solubiliza muy rápido, por ello se ensayan polímeros insolubles que permitan modular la liberación de un ingrediente farmacéuticamente activo. Objetivo: evaluar la liberación de pravastatina sódica en matrices poliméricas insolubles de quitosan/PF-127 con el método de paleta sobre disco para obtener su perfil cinético de liberación, con la finalidad de proponerse como matrices viables para la elaboración de parches transdérmicos. Métodos: se realizaron estudios de contenido químico, diámetro y espesor de las películas, calorimetrías de barrido diferencial y estudios de liberación. La cuantificación del principio activo se realizó mediante espectrofotometría UV-Vis a 238 nm. Resultados: se obtuvieron parches transdérmicos con buena uniformidad de contenido, espesor, diámetro, con una buena estabilidad en base a los estudios de calorimetría. El uso de PF-127 incrementó o retardó la liberación de pravastatina de la matriz polimérica dependiendo de su concentración y al realizarse los perfiles cinéticos de liberación las formulaciones se ajustaron a una cinética de orden 0 que describe el comportamiento de algunos sistemas transdérmicos. Conclusiones: los resultados manifiestan la posibilidad de usar esta matriz polimérica insoluble de quitosana con PF-127 para modular la liberación de pravastatina sódica y de fármacos con estructura similar a la misma por vía transdérmica, lo que generará de esta manera nuevas alternativas a las formas farmacéuticas orales para el tratamiento de padecimientos y enfermedades(AU)

Introduction: the development of transdermal drugs has aroused great interest in recent years due to their advantages, however many of the drug delivery systems use soluble matrix components which could trigger therapeutic problems due to a rapid release of the active ingredient. Therefore, insoluble polymers are being tested that can modulate the release of a pharmaceutically active ingredient. Objective: to evaluate the release of pravastatin sodium in insoluble polymer chitosan/PF-127 matrices by VER to obtain kinetic profile of release in order to submit them as viable systems for the manufacture of transdermal patches. Methods: studies on the chemical content, diameter and thickness of films, differential scanning calorimetry and release studies were performed. The UV-Vis spectrophotometry at 238 nm allowed quantitating the active principle. Results: transdermal patches with adequate uniform drug content, suitable thickness and diameter with good stability, based on calorimetric studies, were obtained. The use of PF-127 increased or delayed the release of pravastatin sodium from the polymeric matrix depending on concentration. When performing the kinetic profiles of release, the formulations were regulated to zero kinetic that describes the behavior of some transdernal systems. Conclusions: the results demonstrated the possibility of using these insoluble polymer chitosan/PF-127 matrices to modulate the release of pravastin sodium and of other structurally similar drugs, thus creating new alternatives to existing pharmaceutical oral forms for treatment of diseases(AU)

Chitosan/guargum-g-acrylamide semi IPN microspheres for controlled release studies of 5-Fluorouracil.

Chitosan and guargum-gt-acrylamide (CH-GG-g-AAm) semi interpenetrating microspheres (semi IPNMs) were prepared by water-in-oil (w/o) emulsion cross linking method using glutaraldehyde as a crosslinker. 5-fluorouracil (5-FU) is an anticancer drug was successfully loaded in these semi IPNMs. X-ray diffraction (XRD) and differential scanning calorimetric (DSC) examined the crystalline nature of drug after encapsulation into semi IPNMs. Scanning electron microscopy (SEM) shows the formation of semi IPNMs is spherical with size around 200 􀀀m. The encapsulation efficiency of 5-FU was achieved 58%. In-vitro release studies were performed basic (pH 7.4) buffer medium. The release patterns depend on graft polymer composition, effect of cross linker and drug content in the polymer matrices. In vitro release studies indicated the release of 5- FU more than 12 hours.