REVIEW LITRETURE 1. Paradkar Anant, et, al, (2005), Patil Pradeep, et, al, (2004), 3. Kommuru, T.R., et, al., (2001),

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1 REVIEW LITRETURE 1. Paradkar Anant, et, al, (2005), formulated the porous Polystyrene Beads as Carriers for Self- Emulsifying System Containing Loratadine. They formulated a self-emulsifying system (SES) containing a lipophilic drug, loratadine, and to explore the potential of preformed porous polystyrene beads (PPB) to act as carriers for such SES. Isotropic SES was formulated, which comprised Captex 200 (63% wt/wt), Cremophore EL (16% wt/wt), Capmul MCM (16% wt/wt), and loratadine (5% wt/wt). SES was evaluated for droplet size, drug content, and in vitro drug release. SES was loaded into preformed and characterized PPB using solvent evaporation method. SESloaded PPB were evaluated using scanning electron microscopy (SEM) for density, specific surface area (SBET), loading efficiency, drug content, and in vitro drug release. After SES loading, specific surface area reduced drastically, indicating filling of PPB micropores with SES. Loading efficiency was least for small size (SS) and comparable for medium size (MS) and large size (LS) PPB fractions. In vitro drug release was rapid in case of SS beads due to the presence of SES near to surface. LS fraction showed inadequate drug release owing to presence of deeper micropores that resisted outward diffusion of entrapped SES. Leaching of SES from micropores was the rate-limiting step for drug release. Geometrical features such as bead size and pore architecture of PPB were found to govern the loading efficiency and in vitro drug release from SES-loaded PPB Patil Pradeep, et, al, (2004), studied, Effect of Formulation Variables on Preparation and Evaluation of Gelled Self-emulsifying Drug Delivery System of Ketoprofen, The purpose of this study was to formulate a gelled self-emulsifying drug delivery system containing ketoprofen as an intermediate in the development of sustained release solid dosage form. Captex 200 (an oil), Tween 80 (a surfactant), and Capmul MCM (a cosurfactant) were used to formulate SEDDS. Silicon dioxide was used as a gelling agent, which may aid in solidification and retardation of drug release. Effect of concentrations of cosurfactant and gelling agent on emulsification process and in vitro drug diffusion was studied using 3 2 factorial design. Multiple regression analysis data and response surfaces obtained showed that liquid crystal phase viscosity increased significantly with increasing amount of silicon dioxide, which in turn caused an increase in average droplet size of resultant emulsion and slower drug diffusion. Drug release from the formulation increased with increasing amount of cosurfactant Kommuru, T.R., et, al., (2001), studied, Self-emulsifying drug delivery systems of coenzyme Q"1"0: formulation development and bioavailability assessment. The goals of our investigations are to develop and characterize self-emulsifying drug delivery systems of coenzyme Q"1"0 (CoQ"1"0), using polyglycolyzed glycerides (PGG) as emulsifiers and to evaluate their bioavailability in dogs. Solubility

2 of CoQ"1"0 was determined in various oils and surfactants. SEDDS consisted of oil, a surfactant and a cosurfactant. From these studies, an optimized formulation consisting of Myvacet 9-45 (40%), Labrasol (50%) and lauroglycol (10%) was selected for its bioavailability assessment. A two-fold increase in the bioavailability was observed for the self-emulsifying system compared to a powder formulation. SEDDS have improved the bioavailability of CoQ"1"0 significantly. The data suggest the potential use of SEDDS to provide an efficient way of improving oral absorption of lipophilic drugs Ji-Yeon Hong, et, al, (2006), studied, A new self-emulsifying formulation of itraconazole with improved dissolution and oral absorption.to enhance the dissolution and oral absorption of poorly water-soluble itraconazole, self-emulsifying drug delivery system composed of oil, surfactant and cosurfactant for oral administration of itraconazole was formulated, and its physicochemical properties and pharmacokinetic parameters of itraconazole were evaluated. In fasted and fed normal diet group, AUC 0 24 h and the mean maximum plasma level (C max ) of itraconazole after oral administration of SEDDS in rats were comparable to those of itraconazole after oral dose of Sporanox. These results demonstrate that the SEDDS of itraconazole composed of Transcutol, Pluronic L64 and tocopherol acetate greatly enhanced the bioavailability of itraconazole after the dose, particularly not influenced by food intake or not. Thus, this system may provide a useful dosage form for oral water-insoluble drug without food effect Chae Gang Soo, et, al, (2005), studied, Enhancement of the stability of BCNU using self-emulsifying drug delivery systems and in vitro antitumor activity of self-emulsified BCNU-loaded PLGA wafer. The main purpose of this study was to develop self-emulsifying drug delivery systems SEDDS for the improvement of the stability of 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) after released from poly (D,L-lactide-co-glycolide) (PLGA) wafer and to evaluate its in vitro antitumor activity against 9L gliosarcoma cells. The in vitro stability test of BCNU was characterized by the BCNU amount in phosphate buffered saline (PBS, ph 7.4) at 37 C. SEDDS increased in vitro half-life of BCNU up to 130 min compared to 45 min of intact BCNU. These results strongly suggest that the self-emulsion system increased the stability of BCNU after released from PLGA wafer. From these results, it could be expected that the penetration depth of BCNU could be improved in brain tissue using selfemulsion system O. Chambin, et, al., (2004), studied, Influence of cryogenic grinding on properties of a selfemulsifying formulation, Recently, self-emulsifying drug delivery systems have been developed as a method to deliver lipophilic drugs. Gelucire 44/14 is an excipient, from the lauroyl macrogolglycerides family, producing a fine oil-in-water emulsion when introduced into an aqueous phase under gentle agitation as improving thereby solubility of poorly water-soluble drugs and their bioavailability. The aims of this study were to process Gelucire 44/14 into a powder by cryogenic

3 grinding to produce solid oral dosage forms and to investigate influence of this process on different properties of a formulation made of Gelucire 44/14 and ketoprofen (90/10). Cryogenic grinding produced Gelucire 44/14 in a powder form and this process did not change its physical properties, emulsification capacities and dissolution performances of the formulation tested. However, interactions took place between ketoprofen and Gelucire 44/14 with a decrease of the melting peak and a reduction of the droplet size of the formed emulsion. The influence of drug Gelucire 44/14 interactions must be investigated case by case in any formulations Palamakula Anitha, et, al,(2004), studied, Evaluation of cytotoxicity of oils used in coenzyme Q 10 Self-Emulsifying Drug Delivery Systems.The objective of the present study was to develop a suitable method for evaluation of cytotoxicity of the oils used in SEDDS using Coenzyme Q10 (Co Q 10 ) as a model compound. For this purpose, three methods of sample preparation were tested, namely (i) suspensions, (ii) homogenization, and (iii) nanoemulsions of oils in Dulbecco s Modified Eagle s Media (DMEM). Studies were carried out by incubating the sample or control with Caco-2 cells grown on transwell insert systems as well as in flat bottom 96-well plates. The cell viability was assessed by using WST-1 and propidium iodide reagents while the monolayer integrity was assessed by mannitol permeability and Trans Epithelial Electrical Resistance (TEER). The cytotoxicity of oils was found to be dependent on the method of sample preparation; nanoemulsions being the least cytotoxic. In conclusion, nanoemulsification is a useful tool for cytotoxicity evaluation of substances, which exhibit poor aqueous/dimethyl sulfoxide (DMSO) solubility Neslihan R., et, al., (2004), studied, SEDDS for improved oral delivery of lipophilic. The oral delivery of hydrophobic drugs presents a major challenge because of the low aqueous solubility of such compounds. Self-emulsifying drug delivery systems, which are isotropic mixtures of oils, surfactants, solvents and co-solvents/surfactants, can be used for the design of formulations in order to improve the oral absorption of highly lipophilic drug compounds can be orally administered in soft or hard gelatin capsules and form fine relatively stable oil in water (o/w) emulsions upon aqueous dilution owing to the gentle agitation of the gastrointestinal fluids. The active compounds of which have been formulated into specific Significant improvement in the oral bioavailability of these drug compounds has been demonstrated for each case. The fact that almost 40% of the new drug compounds are hydrophobic in nature implies that studies with will continue, and more drug compounds formulated as will reach the pharmaceutical market in the future Shui-Mei Khoo, et,al., (1998), studied, Formulation design and bioavailability assessment of lipidic self-emulsifying formulations of halofantrine.the potential for lipidic self-emulsifying drug delivery systems and self-microemulsifying drug delivery systems (SMEDDS) to improve the oral bioavailability of a poorly absorbed, antimalarial drug (Halofantrine, Hf) was investigated in fasted

4 beagles. Hf free base, rather than the commercially available hydrochloride salt (Hf.HCl), was studied due to its much higher solubility in lipidic triglyceride solvents. The multi-component delivery systems were optimized by evaluating their ability to self-emulsify when introduced to an aqueous medium under gentle agitation, and by determination of particle size of the resulting emulsion. Optimized formulations selected for bioavailability assessment were medium-chain triglyceride and SMEDDS, and a long-chain triglyceride SMEDDS. The relevant pharmacokinetic parameters of Hf, and its desbutyl metabolite, were determined relative to an intravenous formulation. The lipid-based formulations of Hf base afforded a six- to eight-fold improvement in absolute oral bioavailability relative to previous data of the solid Hf.HCl tablet formulation. These data indicate the utility of dispersed lipid-based formulations for the oral delivery of Hf free base, and potentially other lipophilic drugs P. Chris de Smidt, et, al., (2004), studied, Intestinal absorption of penclomedine from lipid vehicles in the conscious rat: contribution of emulsification versus digestibility.the inclusion of highly lipophilic compounds in SEDDS is often reported to result in strongly enhanced oral absorption. The data in the current investigation emphasize the prominent role of increased vehicle dispersion relative to digestibility in the absorption of Pcm from MCT-TPGS in submicron emulsions. Only with Pcm administered as undispersed MCT, absorption was more dependent on the action of lipase as bioavailability was inhibited two-fold by the co-incorporation of THL Johanna Mercke Odeberg, et, al., (2003), studied, Lipid drug delivery and rational formulation design for lipophilic drugs with low oral bioavailability, applied to cyclosporine. By using a rational formulation approach, we have tried to find the general characteristics for promising selfemulsifying drug delivery systems based on natural lipid components, for the oral delivery of lipophilic drugs. Galactolipids, which are polar lipids commonly found in the chloroplast membranes of green plants, and a natural part of the human diet, were the main surfactants in these formulations. The pharmacokinetic parameters, which describe the rate and extent of absorption, were estimated. We found that fractionated oat oil and medium chain monoglycerides (60:30:10 mono-, di- and tri-glycerides) promoted absorption, and resulted in a formulation with absorption characteristics nearly equal to the commercial formulation of cyclosporine, Sandimmun Neoral Caitriona M. O Driscoll, et, al.,(2002), studied, Lipid-based formulations for intestinal lymphatic delivery. The current state of the art of intestinal lymphatic transport is given by reviewing the more recent publications, which have utilized lipid-based vehicles. Using this parameter results obtained to date, with lipid-based vehicles, are somewhat disappointing maximising at approximately 20 30%, for highly lipophilic compounds including DDT and halofantrine (Hf). Recent data, monitoring Hf, in a fed versus fasted dog study, have shown that a higher degree of lymphatic transport is

5 possible (>50% dose) in the post prandial state, this study should result in stimulating renewed interest in the potential of achieving significant levels of lymphatic targeting. Although some relevant features controlling lymphatic transport have been identified over the years a deeper appreciation of all the mechanisms, which is vital for therapeutic exploitation of lymphatic transport, is still unrealized. This review analyses the success and limitations of a formulation approach using lipid-based vehicles and highlights potential areas for further research Pouton Colin W., et, al., (2000), studied, Lipid formulations for oral administration of drugs: nonemulsifying, self-emulsifying and self-microemulsifying drug delivery systems. Lipid formulations for oral administration of drugs generally consist of a drug dissolved in a blend of two or more excipients, which may be triglyceride oils, partial glycerides, surfactants or co-surfactants. More data is needed on the solubility of drugs in various types of formulations, and in particular, on the relationship between the physical chemistry of the drug and its fate, subsequent to dilution and digestion of the formulation in the lumen of the gastrointestinal tract. The mechanisms of action and practical uses of each type of lipid formulation are discussed MacGregor Karen J., et, al., (1997), studied, Influence of lipolysis on drug absorption from the gastro-intestinal tract. Bioavailability of hydrophobic drugs from the gastro-intestinal (GI) tract can be enhanced by formulation in digestible oils. This form of delivery is an effective way of avoiding the slow dissolution step which limits availability from solid dosage forms. Essentially the drug remains in solution during its passage and prior to absorption. Here we review the solubilization of drugs in bile salt micelles, describe methods which can be used for assessment of lipolysis in vitro, and present preliminary biostudies using formulations optimized for rapid lipolysis. There is a need for more systematic studies on the influence of lipolysis on absorption from the GI tract, but current data suggest that optimisation of lipolysis will be an important strategy in formulation of oily systems Colin W. Pouton, et, al., (1997), studied, Formulation of self-emulsifying drug delivery. Selfemulsifying drug delivery systems are mixtures of oils and surfactants, ideally isotropic, sometimes including cosolvents, which emulsify under conditions of gentle agitation, similar to those which would be encountered in the gastro-intestinal tract. Hydrophobic drugs can often be dissolved in SEDDS allowing them to be encapsulated as unit dosage forms for peroral administration. When such a formulation is released into the lumen of the gut it disperses to form a fine emulsion, so that the drug remains in solution in the gut, avoiding the dissolution step which frequently limits the rate of absorption of hydrophobic drugs from the crystalline state. This article describes strategies used for formulation of SEDDS, methods used for assessment of efficiency of emulsification and practical

6 considerations regarding the use of for enhancement of the bioavailability of drugs from the gastrointestinal tract Shah N. H., et, al., (1994), studied, Self-emulsifying drug delivery systems with polyglycolyzed glycerides for improving in vitro dissolution and oral absorption of lipophilic drugs. The ability of polyglycolyzed glycerides (PGG) with varying fatty acid and polyethylene glycol (PEG) chain lengths to produce the self-emulsification of oil in water has been investigated. The quality of the resulting emulsions depends on the oil and emulsifier pair selected. A phase diagram was used to obtain the optimum concentrations of drug, oil and emulsifying agent. The results obtained with PGG were compared with previously reported SEDDS for the efficiency of drug release (Bachynsky et al., (1989) AAPS Annual Meeting). In vitro dissolution and in vivo absorption of a lipophilic drug from SEDDS are compared with those properties of other dosage forms Craig D. Q. M., et, al., (1993), studied, An investigation into the physico-chemical properties of selfemulsifying systems using low frequency dielectric spectroscopy, surface tension measurements and particle size analysis. The structure and behaviour of self-emulsifying drug delivery systems containing Labrafil M2125 CS and Tween 80 have been examined and the effects of changing the formulation via the addition of a non-polar model drug (L-365,260) investigated. It was found that the bimodal distribution changed over a period of 14 h, with a decrease in modal value of the larger distribution peak and, for samples containing no drug, an increase in the proportion of droplets in the lower size distribution. The results therefore indicate that the drug interacts with one or more components of the self-emulsifying system, leading to a change in droplet size distribution which varies as a function of drug concentration Bok Ki Kang, et, al., (2003), Developed the self-microemulsifying drug delivery systems(smedds) for oral bioavailability enhancement of simvastatin in beagle dogs. The main purpose of this work is to prepare self-microemulsifying drug delivery system (SMEDDS) for oral bioavailability enhancement of a poorly water soluble drug, simvastatin. Solubility of simvastatin was determined in various vehicles. SMEDDS is mixture of oils, surfactants, and cosurfactants, which are emulsified in aqueous media under conditions of gentle agitation and digestive motility that would be encountered in the gastro-intestinal (GI) tract. Pseudo-ternary phase diagrams were constructed to identify prefilled hard capsules to fasted beagle dogs. The absorption of simvastatin acid from SMEDDS form resulted in about 1.5-fold increase in bioavailability compared with the conventional tablet. Our studies illustrated the potential use of SMEDDS for the delivery of hydrophobic compounds, such as simvastatin by the oral route. 19. Bailey Carole A., et, al., (1996), studied the use of the intestinal epithelial cell culture model, Caco- 2, in pharmaceutical development. The need for more innovative and readily orally bioavailable

7 therapeutics that can be developed faster has driven the development of tools and strategies that will have a major impact on those needs. The application of the Caco-2 human epithelial cell line for use as a tissue culture model for permeability measurements that can be used to predict oral absorption effectively demonstrates this strategy. This article discusses some of the strategic applications of the Caco-2 tissue culture model in pharmaceutical development. The development of an experimental program to characterize the endogenous gut peptide transport system is described, as well as its application to the understanding of the oral absorption of cephalosporin molecules. Other studies describe the use of permeability studies for a chemical series of drug candidates to predict their oral absorption in vivo. Finally. the application of the model to aid in the development of formulation strategies is discussed. 20. Matuszewska Bozena, et, al.,(1996),reported comparative bioavailability of L-683,453, a 5αreductase inhibitor, from a self-emulsifying drug delivery. Bioavailabilities (BA) of the lipophilic compound, L-683,453, from several formulations were determined in fasted and fed purpose-bred Beagle dogs following oral administration and an i.v. reference dose. It was found that tolerability and efficacy of MDG-based formulations at 16 mg/kg depend not only on the dose but also on the dosing volume. A volume of 2 ml/kg caused emesis, while a volume of 1 ml/kg was well tolerated. In contrast to its effect on suspensions, food had no statistically significant effect on BA of selfemulsifying formulations at dosing volumes of 1 ml/kg and 0.25 ml/kg. However, peak plasma concentrations were achieved faster in ted than in fasted animals. 21. Ping Lia et, al., (2005), checked Effect of combined use of nonionic surfactant on formation of oil-inwater microemulsions, Purpose: This study evaluated the effects of combined use of two nonionic surfactants on the characteristics (i.e., appearance, emulsification time, and particle size) of oil-inwater microemulsions generated from flurbiprofen-loaded preconcentrates. The combined use of surfactants in preconcentrate showed the promise in generating desired self-emulsifying microemulsions with small particle size, increased drug loading, and improved physical stability. This will have significant implications in future dosage development for poorlywater-soluble drugs in using self-emulsifying microemulsions drug delivery system (SMEDDS). 22. Y.G. Bachhav a, et, al., (2006), studied, Exploring the potential of N-methyl pyrrolidone as a cosurfactant in the microemulsion systems. The effect of N-methyl pyrrolidone (NMP) on the phase behavior of two ternary systems, viz. PEG-35-castor oil (Cremophore EL) glyceryl caprylate/caprate (Capmul MCM) water and PEG-35-castor oil (Cremophore EL) isopropyl myristate water was studied. The study indicated that NMP has considerable influence on the phase behavior of both the systems. NMP increased the area of microemulsion formation in both the systems. Moreover, it also led to reduction/disappearance in the gelling region of the Cremophore EL isopropyl myristate

8 water system. These observations allowed us to conclude that NMP can be considered as a cosurfactant for the development of biocompatible microemulsions. 23. Ehab I. Taha a, et, al., (2004), Prepared and characterized of self-nanoemulsified drug delivery system (SNEDDS) of all-trans-retinol acetate, Purpose: To prepare a self-nanoemulsified drug delivery system of all-trans-retinol acetate, with enhanced dissolution and better chance of oral absorption. The present study revealed that the self-nanoemulsified drug delivery system of alltrans-retinol acetate increased its dissolution rate and has the potential to enhance its bioavailability without interaction or incompatibility between the ingredients. 24. Hiroshi Araya a, et, al., (2005),designed the O/W microemulsion for improving the gastrointestinal absorption of poorly water soluble compounds, The design of the novel O/W microemulsion formulation, which enhances the oral bioavailability by raising the solubility of poorly water soluble compounds was examined. The AUCs in plasma concentration of Ibuprofen and a new compound, ER-1039, following single oral administration of these compounds as the O/W microemulsion to fasted rats were equivalent to that of solution administration or increased by nine and two times that of suspension administration, respectively. Accordingly, this novel O/W microemulsion is a useful formulation, which enhances the oral bioavailability by raising the solubility of poorly water soluble compounds. 25. D. Q. M. Craiga, et, al., (1993), investigated the physico-chemical properties of self-emulsifying systems using low frequency dielectric spectroscopy, surface tension measurements and particle size analysis, The structure and behaviour of self-emulsifying drug delivery systems (SEDDS) containing Labrafil M2125 CS and Tween 80 have been examined and the effects of changing the formulation via the addition of a non-polar model drug (L-365,260) investigated. It was found that the bimodal distribution changed over a period of 14 h, with a decrease in modal value of the larger distribution peak and, for samples containing no drug, an increase in the proportion of droplets in the lower size distribution. The results therefore indicate that the drug interacts with one or more components of the self-emulsifying system, leading to a change in droplet size distribution which varies as a function of drug concentration. 26. N. H. Shah, et, al., (1994), reviewed the Self-emulsifying drug delivery systems (SEDDS) with polyglycolyzed glycerides for improving in vitro dissolution and oral absorption of lipophilic drugs, The ability of polyglycolyzed glycerides (PGG) with varying fatty acid and polyethylene glycol (PEG) chain lengths to produce the self-emulsification of oil in water has been investigated. The quality of the resulting emulsions depends on the oil and emulsifier pair selected. The results indicate that PGG are effective emulsifiers for SEDDS. A phase diagram was used to obtain the optimum concentrations of drug, oil and emulsifying agent. The results obtained with PGG were compared

9 with previously reported SEDDS for the efficiency of drug release (Bachynsky et al., (1989) AAPS Annual Meeting). In vitro dissolution and in vivo absorption of a lipophilic drug from SEDDS are compared with those properties of other dosage forms. 27. Sami Nazzal, et, al., (2002), reviewed a Response Surface Methodology for the Optimization of Ubiquinone Self-Nanoemulsified Drug Delivery System. The aim of the present study was to prepare and evaluate an optimized, self-nanoemulsified drug delivery system of ubiquinone. Increasing the amount of the eutectic agent was necessary to overcome drug precipitation especially at higher loading of surfactants and cosurfactants. Mathematical equations and response surface plots were used to relate the dependent and independent variables. The optimization model predicted a 93.4% release with X1, X2, and X3 levels of 35, 35, and 30 respectively. The observed responses were in close agreement with the predicted values of the optimized formulation. This demonstrated the reliability of the optimization procedure in predicting the dissolution behavior of a self-emulsified drug delivery system. 28. Charman SA, et, al., (1992), reviewed the self-emulsifying drug delivery systems: formulation and biopharmaceutic evaluation of an investigational lipophilic compound. Self-emulsifying drug delivery systems (SEDDSs) represent a possible alternative to traditional oral formulations of lipophilic compounds. In the present study, a lipophilic compound, WIN 54954, was formulated in a medium chain triglyceride oil/nonionic surfactant mixture which exhibited self-emulsification under conditions of gentle agitation in an aqueous medium. The SEDDS improved the reproducibility of the plasma profile in terms of the maximum plasma concentration (Cmax) and the time to reach the maximum concentration (tmax). There was no significant difference in the absolute bioavailability of WIN from either the SEDDS or the PEG formulations 29. Feng-Feng Lv, et, al., (2005), studied, Phase behavior of the microemulsions and the stability of the chloramphenicol in the microemulsion-based ocular drug delivery system. Effects of chloramphenicol, normal saline, sodium hyaluronate and various oils on the phase behavior were studied. The phase transition was investigated by the electrical conductivity measurements. The electrical conductivity of the microemulsion was affected by the encapsulation of the drug into the system, and the addition of normal saline and sodium hyaluronate. The results of HPLC revealed that the contents of the glycols in the microemulsion formulations were much lower than that in the commercial eye drops at the end of the accelerated experiments. The nitro-groups of the chloramphenicol molecules were near the α2-ch2 of the surfactant molecules and the benzene rings of the chloramphenicol molecules were near the oxyethylene groups of the surfactant molecules. It was this reason that enabled the chloramphenicol molecules in the microemulsions to be screened from the bulk water and its stability to be increased remarkably.

10 30. Patel Maulik J.,et.al.,(2010), formulated and evaluated the self-microemulsifying drug delivery system of Lovastatin which is a poorly water soluble drug. It should be come into the BCS II drug. So oral bioavailability of lovastatin is less (50%). To develop novel dosage foam of the selfmicroemulsifying drug delivery systems (SMEDDS) for the lovastatin. In vitro dissolution was carried in USP apparatus II using 0.1 mol/l HCl at 50 r/min. Drug release was measured by spectroscopic method. Results: from the solubility study, better solubility was seen in sunflower oil (oil), Acrysol K140 (surfactant), Capmul MCM C8 (co-surfactant). No any drug exicipients interaction was seen. Droplet size was 18 to 24 nm. Formulation was clear and near to 100% transmittance after dilution with 0.1 mol/l HCl and Water. Drug was release up to 92 % in 1 h. Release data was compare with marketed product and calculate the f2 value and P value. f2 value was and that alue was near to 0 and P value was less than Conclusion: SMEDDS lovastatin oral ormulations were prepared that provide excellent drug solubilization, drug stability in water and 0.1 mol/l HCl and improved in vitro release of lovastatin compare to marked product. 31. Nekkanti Vijaykumar, et. al., (2010), developed the Solid Self-Microemulsifying Formulation for Candesartan Cilexetil. It is a sparingly water-soluble drugs. Candesartan cilexetil offer challenges in developing a drug product with adequate bioavailability. They resulted that solid intermediates showed comparable rate and extent of drug dissolution in a discriminating dissolution medium as liquid SMEDDS indicating that the self-emulsifying properties of SMEDDS were unaffected following conversion. Also, the rate and extent of drug dissolution for solid intermediates was significantly higher than commercial tablet formulation. The results from this study demonstrate the potential use of SMEDDS as a means of improving solubility, dissolution, and concomitantly the bioavailability. 32. B. V Rajesh., et. al., (2009), reviewed the lipid based self emulsifying drug delivery system for poorly water soluble drugs. Oral delivery is not possible for 50% of currently marketed drug compounds due to low oral bioavailability. One of the most popular approaches to enhance the oral bioavailability of these molecules is the utilization of a lipid based drug delivery systems. Self emulsifying drug delivery systems (SEDDS) are a class of lipid based delivery systems. Conventional SEDDS are normally prepared in a liquid dosage form that can be administered in soft gelatin capsules, which have some disadvantages especially in the manufacturing process. Accordingly, Solid-Self emulsifying drug delivery systems (Solid-SEDDS), prepared by solidification of liquid/semisolid self emulsifying ingredients into powders in order to create solid dosage forms. This article focuses on SEDDS and solidification techniques of Solid-SEDDS.

11 33. Bajaj Himani, et. al., (2011), reviewed the self emulsifying drug delivery system for improving the bioavailability of the poorly soluble drugs. They found that aproximately 40 per cent of new drug candidates have poor water solubility and the oral delivery of such drugs is frequently associated with implications of low bioavailability, high intra and inter-subject variability, and lack of dose proportionality. Bioavailability problem of lipophillic drugs can be solved by formation of Self Emulsifying Drug Delivery System (SEDDS). SEDDS appears to be a unique and industrially feasible approach to overcome the problem of low oral bioavailability associated with the lipophillic drugs. Self-emulsifying formulations are mixtures of oils and surfactants, ideally isotropic, and sometimes containing co-solvents, which emulsify spontaneously to produce fine oil-in-water emulsion when introduced into aqueous phase under conditions of gentle agitation.