Biopolymer in Gene Delivery

Nowadays, biopolymers, a class of biomaterials, represent frontier area in the drug delivery systems. Drug release from nano- and microparticles is a complex process, which involves several steps. Uptake of nanoparticle in the intracellular is affected by numerous factors. Recently, gene delivery has been considered one of the promising approaches for the treatment of various diseases acquired genetically in human being. The use of biopolymers as nanoparticles in gene delivery can potentially avoid many of the safety concerns in the gene delivery system. In gene delivery, the genetic materials such as DNA plasmids, RNA and siRNA are either encapsulated inside or conjugated to the nanoparticles, which protects the genetic materials until the drug reaches its target site. Treatment of the diseases is based on the effective delivery of the genetic materials into specific cells that are responsible for disease development. Various properties such as particle size, surface charge, morphology of the surface and release rate of the loaded molecules are the important parameters in the gene delivery system. In this chapter, various biopolymers (cationic polymers) and inorganic non-viral-delivery vectors used in gene delivery used as therapeutic agents are discussed

Medicated Nanoparticle for Gene Delivery

Delivering the drug to the target site with a desired concentration to provide therapeutic effect is a major problem in the drug delivery system. Effectiveness, poor distribution and lack of selectivity are the drawbacks of the conventional dosage form. Recently Nanotechnology has been given much attention in various fields specifically in the biomedical application. Material includes organic, inorganic, polymeric and lipid-based nanobiomaterials after surface modification; it has been utilized for drug and gene delivery systems. Viral and non-viral vectors are the two types in gene delivery utilizing genetic materials like DNA plasmids, RNA and siRNA. Cellular and extracellular barriers are the two main barriers in gene delivery. The basic mechanism involved in the gene delivery is an introduction of a gene encoding a functional protein altering the expression of an endogenous gene or owning the capacity to cure or prevent the progression of a disease. Nanoparticle surface features like particle shape and surface charge are having major roles in the gene delivery. To provide the site-specific delivery various properties like nature of polymer, particle size, solubility, biocompatibility, biodegradability and nanoparticle surface features are need to be considered. Gene delivery has been utilized for various disease treatments such as cancer, AIDS, and cardiovascular diseases

Formulation and evaluation of sustained release microspheres of rosin containing aceclofenac

Aceclofenac was microencapsulated using rosin by o/w emulsion solvent evaporation technique. The effect of three formulation variables including the drug:polymer ratio, emulsifier (polyvinyl alcohol) concentration and organic solvent (dichloromethane) volume were examined. The prepared batches were characterized for microspheres particle size distribution, encapsulation efficiency and in vitro release behavior. The study reveals that drug:polymer ratio had a considerable effect on the entrapment efficiency, however particle size distribution of microspheres was more dependent on the volume of dichloromethane and polyvinyl alcohol concentration rather than on the drug: polymer ratio. Drug, polymer concentrations were varied to obtain optimum release profile for sustaining the action of the drug

Design and Evaluation of Matrix Diffusion Controlled Transdermal Patches of Diltiazem Hydrochloride

Se desarrolló un sistema matricial de tipo dispersivo para la administración transdérmica de clorhidrato de Diltiazem usando diferentes proporciones de colofonia con Eudragit RL PM y polivinil pirrolidona. El parche preparado con colofonia y polivinil pirrolidona no era transparente y muestra una distribución irregular de polivinil pirrolidona, lo que puede ser debido al carácter hidrófi lo de ésta. Se investigó el efecto de los polímeros sobre las propiedades tecnológicas; es decir, la liberación del fármaco, la velocidad de transmisión del vapor de agua, la pérdida porcentual de humedad y el grosor. El parche con colofonia: Eudragit RL PM (6:4) dio como resultado una liberación de 2651 mcg en 24 horas. Con el objeto de mejorar la liberación, se incluyeron distintas proporciones de alcanfor en la formulación. El parche con colofonia: Eudragit RL PM (6:4) y un 5% p/v de alcanfor dio como resultado una liberación constante del fármaco a lo largo de un período de 24 horas. La formulación F8 resultó ser la más satisfactoria en lo que a las propiedades tecnológicas se refi ere. Se llevaron a cabo estudios posteriores de permeación e irritación de la piel en ratas y conejos respectivamente. Por lo tanto, se puede concluir que con el parche de colofonia: Eudragit RL PM en proporción 6:4 con un 5% p/v de alcanfor, se alcanzan los objetivos deseables en sistemas de administración transdérmica de fármacos tales como anular el efecto de primer paso, una amplia liberación y una frecuencia de administración reducida.A matrix dispersion type transdermal drug delivery system of Diltiazem Hydrochloride was developed using different ratios of rosin with Eudragit RL PM and polyvinyl pyrrolidone. The patch prepared by the combination of rosin and polyvinyl pyrrolidone was not transparent one, and shows an uneven distribution of polyvinyl pyrrolidone, which may be due to the hydrophilic nature of polyvinyl pyrrolidone. The effect of the polymers on the technological properties, i.e., drug release, water vapor transmission rate, percentage moisture loss and thickness were investigated. The patch containing rosin: Eudragit RL PM (6:4) showed a release of 2651 mcg in 24 h. In order to improve the release various proportions of camphor was included in the formulation. The patch containing rosin: Eudragit RL PM (6:4) with 5% w/v of camphor showed a sustained release of the drug extending over a period of 24 h. Formulation F8 emerged as the most satisfactory formulation as far as the technological properties were concerned. Further skin permeation and skin irritation studies were carried out on rat skin and rabbit respectively. Therefore it can be concluded that the patch containing rosin: Eudragit RL PM in the ratio 6:4 with 5%w/v of camphor achieved the desired objectives of transdermal drug delivery systems, such as overcoming of fi rst pass effect, extended release and reduced frequency of administration

HPTLC method for quantitative determination of granisetron hydrochloride in bulk drug and in tablets

A new simple, rapid and reproducible high performance thin layer chromatographic method has been developed and validated for the analysis of granisetron hydrochloride (GSH) in bulk drug and from pharmaceutical formulation. The chromatographic separation was achieved on HPTLC aluminium plates precoated with silica gel 60F254 as the stationary phase with chloroform: methanol (80:20 %v/v) as mobile phase. The method gives a compact band for GSH (Rf value of 0.45 ± 0.02). Densitometric analysis of GSH was carried out in the absorbance mode at 301 nm. The linear regression analysis data for the calibration plots showed good linear relationship with the correlation coefficient of 0.9980 with respect to peak area in the concentration range of 400-1600 ngband-1. The method was validated for accuracy, precision, recovery studies, specificity, sensitivity, limit of detection and limit of quantification. Statistical analysis proved the method was precise, reproducible, selective, specific, and accurate for analysis of GSH. The wide linearity range, sensitivity, accuracy, and simple mobile phase composition imply the method is suitable for routine quantification of GSH with high precision and accuracy in bulk drug and marketed oral solid dosage form.Colegio de Farmacéuticos de la Provincia de Buenos Aire