Current Issue : July - September Volume : 2010 Issue Number : 2 Articles : 15 Articles
This review describes methods and efforts that try to use clinic tumor histological specimen for tumor specific antibody generation by means of two powerful technologies: Laser capture microdissection (LCM) and phage display technology. The rationality of combining these two methods is stated and technological details are described. The design and practice of an in situ panning method is described and the potential clinical application discussed....
Poorly water-soluble drugs such as Camptothecin Analog (CA) offer challenges in developing a drug product with adequate bioavailability. The objective of the present study was to develop a tablet dosage form of CA incorporating drug nanoparticles to increase its saturation solubility and dissolution rate for enhancing oral bioavailability. The bioavailability of CA is dissolution limited following oral administration. To enhance bioavailability and overcome variability in systemic exposure, a nanoparticle formulation of CA was developed. Drug nanoparticles were prepared using a wet bead milling technique. The milled nanosuspension was converted into solid intermediate using a spray granulation process. The nanosuspensions were characterized for particle size before and after spray granulation. The spray granulated nanoparticles were blended with excipients for tableting. The saturation solubility and dissolution characteristics of the nanoparticle formulation were investigated and compared with micronized and as-is drug formulations to ascertain the impact of particle size on drug dissolution. The drug nanoparticles were evaluated for solid-state transitions before and after milling using differential scanning calorimetry (DSC) and powder X-ray diffraction (PXRD). The results demonstrated that tablet formulation incorporating drug nanoparticles showed significantly faster rate of drug dissolution in a discriminating dissolution medium as compared to micronized drug formulation. There was no effect on solid-state properties of drug on milling. Systemic exposure studies in rats indicated a significant increase in the rate and extent of drug absorption with nanoparticle formulation. The manufacturing process used is relatively simple and scalable indicating general applicability to enhance dissolution and bioavailability of poorly soluble compounds....
The aim of the current study is to develop a multiparticulate, high loading, colon targeted drug delivery system for mesalazine (5-ASA) suitable for once daily dosing by incorporating pH responsive polymers (Eudragit S and/or Eudragit L) into matrix based tablets composed of hydrophilic-hydrophobic polymers. The compatibility of the drug with formulation components was established by differential scanning calorimetry (DSC) and Fourier transform infra-red (FTIR) spectroscopy. Matrix tablets were prepared by wet granulation technique and were characterized for physical parameters, in-vitro drug release, release kinetics, and stability on storage. A 16-hr drug release profile with no or negligible release in the initial phase (4hr) followed by controlled release for 12hr was proposed as an ideal, targeted profile and was deduced from 5-ASA release profile of the once daily marketed product. In-vitro release studies indicated that the presence of pH-sensitive polymers in retarded the initial release (≈15% release in 4 hr) followed with controlled release for the next 12hr in simulated GI fluid pH. Such a matrix design could have potential application as colon-specific drug delivery systems with pH and time-dependent drug release profile....
Solubility and permeability are most prerequisite for oral absorption of drugs to achieve maximum bioavailability from a dose of drug. Telmisartan is an angiotensin receptor blocker with poor aqueous solubility due to which its bioavailability is very less. For enhancing solubility & dissolution rate of Telmisartan a novel porous drug matrices are formulated by emulsification followed by spray drying. The porous drug matrices of Telmisartan is prepared by using hydrophilic non-ionic surfactant of general class copolymers such as Polaxomer 407(PXM 407), Poly vinyl Pyrrolidone (PVP K30) as a hydrophilic carriers and Hexane as a liquid pore forming agent. Various Drug: Polymers ratios are used to know the effect of polymer concentration on solubility and dissolution rate. Physical mixtures are formulated with drug and polymer. All the formulations (Physical mixtures and porous drug matrices) were subjected to IR spectral analysis & Dissolution studies to investigate compatibility as well as effect of method on dissolution rate. The dissolution rate is aimed to enhance by enhancing surface area by increasing porosity. The dissolution studies are characterized using USP dissolution apparatus II at 50 rpm. From the dissolution data porous drug matrices with PVP K30 having drug: polymer ratio of 1:4 showed more dissolution rate. The Q value was achieved within 20 minutes and 100% drug release was achieved within 60 minutes. The application of Hixson and crowells model has regression values of 0.999 conforming the influence of porous drug matrices on surface area. The kinetic analysis of dissolution data showed that Telmisartan followed first order release from porous drug matrices....
Various natural polymers have been investigated for their applications as pharmaceutical adjuants. Natural materials are preferred in the field of drug delivery because they are readily available, cost-effective, eco-friendly, capable of multitude of chemical modifications, potentially degradable and compatible due to their natural origin. Neem gum, a biopolymer obtained from the plants, is used as a binder in pharmaceutical industries, as a stabilizing agent, thickening agent in food industry; as an adhesive in paint industry. India produces and uses neem gum for a variety of purposes because of her tradition. The present study was focused on application potential of neem gum as a film forming material. The objectives of the study are characterization and evaluation of Neem gum also preparation and evaluation of Neem gum films.Neem gum was characterized for physico-chemical properties namely, solubility, ash values, acid value, pH, viscosity. Neem gum films were prepared by using suitable plasticizer by casting technique. The films were evaluated for thickness, moisture content, tensile strength, moisture uptake/ loss, water vapor transmission study. It was observed that 10% w/w polymer concentration and 30% to 50% w/w concentration of propylene glycol, as a plasticizer, were optimum for formation of Neem gum films. The free films of Neem gum exhibited substantially less moisture content, good mechanical strength, low moisture uptake and low water vapor transmission rates. Low water vapor transmission rates of the free films of Neem Gum indicated good moisture protecting ability of films. It was concluded that Neem gum is a potential film forming agent....
The aim of this search was to formulate and evaluate of Bisoprolol hemifumarate buccal delivery systems. Several tablet formulae were produced by using carboxy methyl cellulose (CMC), polyvinyl pyrrolidone (PVP K30, PVP K90), polyethylene glycol (PEG 4000, PEG 6000), microcrystalline cellulose (Avicel 101, Avicel 102), mannitol and lactose. Drug- Excepients interaction was characterized by DSC analysis. The prepared tablet formulae were evaluated according to their crushing strength, disintegration time, friability, and content uniformity, in vitro drug release using USP dissolution tester and bioavailability study in albino rabbits. All tablet formulae had acceptable hardness, friablility and short disintegrating time. Tablet formula 3 containing (PVP K30 and mannitol) gave the highest drug concentration in rabbits plasma in comparison to other formulae and oral commercial formula....
Peptic ulcer being one of the most rampant gastrointestinal disorders continues to occupy the key position in concern of researchers. Unfortunately most of the drugs used to treat this confer simple to sever side effects like arrythmias, gynacomastia, and heamotopoeitic changes. In this context our research was focused on recent herbal initiative piperine, proposed to be used in treating the gastric ulcers. Floating beads of piperine were prepared by using natural polymer sodium alginate by following ionotropic gellation method with the inclusion of gas liberating agents and swelling polymer. They were evaluated for various floating properties and drug release properties. The percentage yield was found to be around 75%. Swelling ratio was found to be 85% to 132% and the drug encapsulation efficiency was 65% to 81%. Percent cumulative drug release was found to be from 68 to 95%. The floatation time is more than 12 h. The results were encouraging as our formulation contains indigenous drug with fewer side effects to have a better and safer alternative treatment for peptic ulcer....
The aim of present study was to prepare buccal disintegrating tablets of Captopril, a bitter drug by using super-disintegrants addition technique. Buccal disintegrating tablets of Captopril was prepared in order to increase patient compliance, good taste, rapid disintegration, enhancing bioavailability, reduce error in taking medication and offer more efficacy than conventional tablet. Also, effective taste masking achieved by formation of beta-cyclodextrin inclusion complex and evaluated spectrophotometrically. The blend was examined for physical property and then compressed using 8 mm flat punches. Nine formulation batches (F1-F9) were prepared using three different concentrations of superdisintegrants viz Crosscarmellose sodium, Crosspovidone and Sodium Starch Glycolate by direct Compression Method. The concentrations of superdisintegrant were fixed to 6 mg, 12 mg and 18 mg per 150 mg of total weight of tablet to optimize the formulation batches. Compressed tablet were evaluated for hardness, friability, weight variation, drug content and in vitro disintegration time, diffusion study and in vitro dissolution study. All formulations showed compliance with pharmacopoeial standards. The formulated tablets were then compared with the marketed preparation. Prepared batches (F4-F6) shows nearly comparable drug release with marketed tablets, it may be due to the presence of Crosspovidone. The tablets were then subjected to accelerated stability study as per ICH guidelines for the period of three month. Accelerated stability study condition shows negligible changes in drug release for the period of three months....
The purpose of the research was to find out newer antibiotics from Micromonospora species isolated from soil. Actinomycetes species is one of the important source of antibiotics. In spite of the many advances in microbiology, biochemistry, drug discovery and development in recent years, we are not keeping pace with the ability of microbes to adapt to and resist antibacterials. Considering the same this research work was taken up to screen newer antibiotic from soil. The Micromonospora species was obtained from soil collected from different location of Pune and Belgaum. For the isolation of the strain of Micromonospora, crowded plated technique and heat shock mathod was used. The isolate was characterized by studying its morphology , microscopy and also tested for the activity of secondary metabolites. The isolated antibiotic was found bactericidal against Gram negative microorganisms. Environmental parameter like temapature and pH optimization was done to get a maximum yield. The optimum temapareture set at 450C to 500C and pH was set at 6. Antibiotic was extracted from broth by Ethyl acetate. The MIC of the antibiotic obtained was determined against E. coli (0.9 µg/ml). Thin Layer Chromatography of the antibiotic was carried out. The antibiotic was subjected for spectroscopic analysis (UV, IR and NMR)....
Indomethacin microspheres were prepared by emulsion solvent evaporation technique using various coat ratios. The matrixes comprised of hydroxypropyl methyl cellulose (HPMC), ethyl cellulose (EC), Eudragit® RL100 (EuRL100), Eudragit® RS100 (EuRS100) and cellulose acetate (CA). The morphology, flow properties, drug polymer interaction, release mechanism were studied. Anti-inflammatory activity of the prepared microspheres was compared with the commercial product using carrageenan induced paw edema method in rats. Pharmacokinetic evaluation was also carried out by plasma drug concentration method in rabbit to calculate t1/2, Cmax, Tmax, AUC and AUMC and MRT. Results of pharmacokinetic and pharmacodynamic study showed batch V formulation was statistically significant when compared to that of other formulations and marketed drug....
Aim of present study is to prepare and evaluate dual properties of binding and colon targeting efficiency of Abelmoschus esculentus gum tablets containing ibuprofen as a model drug by direct compression technique. Prepared tablets were then evaluated for various formulation characteristics such as physical appearance and surface texture, thickness, hardness, weight variation, % friability, drug content analysis, In-vitro drug release and drug release studies in pH-6.8 phosphate buffer saline with and without 4% rat caecal contents. Characteristics of gum as well as tablets were found acceptable as per standard specifications. Results of drug release studies for formulations (F4 & F5) were found more i.e. 76.71% & 68.51%, when studied in dissolution medium with 4% rat caecal contents in comparison to control medium i.e. 31.45% & 27.24%. It may be due to enzymatic degradation of gum matrix in presence of rat caecal content by colonic bacterial enzymes (such as Bacteroides, Bifidobacterium, Eubacterium, Peptococcus, Lactobacillus, Clostridium etc.). Hence, based on present study, we can conclude that, Abelmoschus esculentus gum can be used as a potential carrier for successful targeting of drug to colon specific drug delivery system in the form of direct compressed tablets....
The microparticles have been utilized for prolonged and uniform drug release of a single dose in the gastrointestinal tract (GIT) and hence reducing the total dose required to elicit therapeutic activity, thereby avoiding the major side effects. The purpose of the present work is to prepare ethyl cellulose microparticles with high entrapment of zidovudine. The (water-in-oil)-in-oil emulsion solvent diffusion technique was used with or without external hydrophobic processing phase saturation with drug at various concentration for microparticles formulations. The prepared microparticles were evaluated with respect to entrapment efficiency, particle size, surface characteristics and in vitro release behavior. The process without external phase saturation produced spherical microparticles with 55 % zidovudine entrapment efficiency. The external phase saturation with 0.1 %, 0.2 % and 0.4 % w/v of drug induced the formation of microparticles with the entrapment efficiency of 60 %, 76 % and 98 %, respectively. The SEM photomicrographs of the freshly prepared microparticles revealed that the surface of the microparticles was smooth and nonporous and / or less porous as compared to the microparticles obtained without incorporation of drug in the external processing medium. A slight increase in yield values and decrease in particle size were observed with microparticles formulations with external phase saturation. The in vitro dissolution studies showed biphasic zidovudine release: the first one corresponds to a burst drug release and the second one to a constant drug release. It is concluded that zidovudine can be encapsulated in ethyl cellulose microparticles with high entrapment using saturated external hydrophobic phase with drug in (water-in-oil)-in-oil emulsion solvent diffusion technique....
Current study was undertaken to improve the flow and tableting properties of solid dispersions of poorly water soluble drug glibenclamide.The solid dispersions of glibenclamide with drug carrier ratio at 1:9 showed superior dissolution rate of 46.05 % when compared with pure drug (3.27 %). Flow and tableting properties of the prepared resulting systems were also evaluated. Interestingly shatavari was very helpful to enhance the flow properties of drug. Moreover, tablets prepared using solid dispersions of glibenclamide were reported to possess the post compression parameters within limit....
Over the years various methods are developed to enhance the drug solubility, liquisolid technique is one of the promising technique. The new fundamental mathematical model introduced by S. Spireas and M. Bolton, 1999; which helps to formulate the liquisolid systems. Liquisolid systems are acceptably flowing and compressible powdered forms of liquid medications. According to the concept of liquisolid systems, liquid lipophilic drugs, or water-insoluble solid drugs dissolved in suitable non-volatile solvents, may be converted into free-flowing and readily compressible powders by a simple admixture with selected powder excipients referred to as the carrier and coating materials. Various grades of Microcrystalline or amorphous cellulose may be used as carrier, whereas very fine particle size Silica powders may be used as coating materials. This review covers the detail aspects of Liquisolid formulation technique for solubility enhancement of poorly soluble drugs. Improved drug release profiles are exhibited by such formulations for poorly soluble drugs....
The objective of the present study was to taste masking of chlorpheniramine maleate (CPM) by spray drying technique and to prepare a PharmagumTM based chewing gum formulations for the treatment of rhinitis, urticaria and allergic disorder conditions. Sucralose and Aerosil�® 200 were used to mask the taste of CPM and the obtained taste masked product was further used in the development of chewable tablet formulations were investigated. Taste masked product and chewing formulations prepared were investigated by differential scanning calorimetry (DSC) and X-ray powder diffraction (PXRD) studies. The chewable tablets were evaluated for thickness, hardness, weight variation, friability, drug content and in vitro dissolution. The DSC and PXRD studies revealed that the compatibility of drug with excipients. Satisfactory results were obtained when tablets evaluated for weight variation, thickness, hardness and friability. In vitro dissolution demonstrated that CPM loaded with PharmagumTM was capable of providing a constant release of the loaded drug over a period of 60 min. The obtained results from the present experiment indicated that PharmagumTM base based formulations of CPM had a positive outcome based on both qualitative observations and quantitative measurements of different parameters....
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