Novel gelatin microcapsule with bioavailability enhancement of ibuprofen using spray-drying technique

A poorly water-soluble ibuprofen and ethanol can be encapsulated in gelatin microcapsule by spray-drying technique. To develop a novel ibuprofen-loaded gelatin microcapsule with bioavailability enhancement, the effect of spray-drying conditions, gelatin, ibuprofen and sodium lauryl sulfate on the ibuprofen solubility and the amount of ethanol encapsulated in gelatin microcapsule were investigated. The ibuprofen solubility and amount of encapsulated ethanol increased as inlet temperature and amount of sodium lauryl sulfate increased, reached maximum at 105 degrees C and 0.6%, respectively and after that followed a rapid decrease. Furthermore, they abruptly increased as the amount of gelatin increased, reaching maximum at 4% then remaining almost stable, but the encapsulated ethanol content decreased noticeably. Likewise, the ibuprofen solubility increased as the amount of ibuprofen increased, reaching maximum at 0.5% and beyond that, there was no change in the solubility. However, the encapsulated ethanol content hardly changed irrespective of the amount of ibuprofen. Furthermore, the formula of ibuprofen-loaded gelatin microcapsule at the ratio of gelatin/ibuprofen/sodium lauryl sulfate/water/ethanol of 4/0.5/0.6/30/70 showed ibuprofen solubility of about 290microg/ml and ethanol content of about 160microg/mg. This gelatin microcapsule dramatically increased the initial dissolution rate of ibuprofen compared to ibuprofen powder in pH 1.2 simulated gastric fluid. Moreover, it gave significantly higher initial plasma concentrations, Cmax and AUC of ibuprofen in rats than did ibuprofen powder, indicating that the drug from gelatin microcapsule could be more orally absorbed in rats. Our results suggested that the enhanced oral bioavailability of ibuprofen in the gelatin microcapsule was contributed by the marked increase in the absorption rate of ibuprofen due to the crystallinity change to amorphous form and increase in dissolution rate of ibuprofen in the gelatin microcapsule in rats. Thus, the ibuprofen-loaded gelatin microcapsule developed using spray-drying technique with gelatin would be useful to deliver ibuprofen in a pattern that allows fast absorption in the initial phase, leading to better absorption.     

Development of nifedipine-loaded coated gelatin microcapsule as a long acting oral delivery

To develop the long acting nifedipine oral delivery with enhanced bioavailability, nifedipine-loaded gelatin microcapsule containing nifedipine and ethanol in gelatin shell was prepared using a spray-dryer, and then coated microcapsule was prepared by coating the gelatin microcapsule with Eudragit acrylic resin. The dissolution test and the bioavailability of the coated microcapsule in rats were evaluated compared to nifedipine powder. The amount of nifedipine dissolved from gelatin microcapsule for 30 min increased about 5-fold compared to nifedipine powder in pH 1.2 simulated gastric fluid. Nifedipine released from the coated microcapsule was retarded in pH 1.2 simulated gastric fluid compared with that from gelatin microcapsule. Furthermore, the coated gelatin microcapsule maintained the plasma level of nifedipine over 4 h and gave significantly higher AUC of nifedipine than nifedipine powder. Thus, the Eudragit-coated gelatin microcapsule, which could maintain the plasma level of nifedipine over a longer period without the initial burst-out plasma concentration, is a preferable delivery system for poorly water-soluble nifedipine.     

Development of novel ibuprofen-loaded solid dispersion with improved bioavailability using aqueous solution

To develop a novel ibuprofen-loaded solid dispersion with enhanced bioavailability, various ibuprofen-loaded solid dispersions were prepared with water, HPMC and poloxamer. The effect of HPMC and poloxamer on aqueous solubility of ibuprofen was investigated. The dissolution and bioavailability of solid dispersion in rats were then evaluated compared to ibuprofen powder. When the amount of carrier increased with a decreased in HPMC/poloxamer ratio, the aqueous solubility of ibuprofen was elevated. The solid dispersion composed of ibuprofen/HPMC/poloxamer at the weight ratio of 10:3:2 improved the drug solubility approximately 4 fold. It gave significantly higher initial plasma concentration, AUC and Cmax of drug than did ibuprofen powder in rats. The solid dispersion improved the bioavailability of drug about 4-fold compared to ibuprofen powder. Thus, this ibuprofen-loaded solid dispersion with water, HPMC and poloxamer was a more effective oral dosage form for improving the bioavailability of poor water-soluble ibuprofen.     

Preparation and in vivo evaluation of piroxicam-loaded gelatin microcapsule by spray drying technique

To develop a piroxicam-loaded gelatin microcapsule with enhanced bioavailability, a gelatin microcapsule encapsulated ethanol and piroxicam has been formulated by using gelatin as a water-soluble polymer shell. The aqueous solubility and bioavailability of piroxicam in piroxicam-loaded microcapsule in rats were then evaluated compared to piroxicam powder. The piroxicam-loaded gelatin microcapsule spherical in shape with smooth surface showed the geometric mean diameter of about 19 microm. It had the piroxicam solubility of about 1.87 mg/ml and the amount of ethanol of about 4.37 microg/mg. Furthermore, it gave significantly higher total plasma concentrations, Cmax and area under the blood concentration-time curve (AUC) of piroxicam in rats than did piroxicam powder, indicating that the drug from gelatin microcapsule could be more orally absorbed in rats. In particular, the AUC of piroxicam in gelatin microcapsule was significantly about 2 fold increased compared to piroxicam powder. This enhanced oral relative bioavailability of piroxicam in gelatin microcapsule was contributed by the marked increase in the absorption rate of piroxicam due to the improved solubility of piroxicam. Thus, the piroxicam-loaded gelatin microcapsule developed using spray-drying technique with gelatin, sodium lauryl sulfate and ethanol would be useful to deliver piroxicam in a pattern that allows fast absorption in the initial phase, leading to better absorption.     

Development of an itraconazole‐loaded gelatin microcapsule with enhanced oral bioavailability: physicochemical characterization and in‐vivo evaluation

Objectives The aim of this study was to develop a novel itraconazole‐loaded gelatin microcapsule without ethanol with enhanced oral bioavailability. Methods Various gelatin microcapsules were prepared using a spray‐drying technique. Their physicochemical properties, dissolution, characteristics and pharmacokinetics in rats were evaluated and compared with those of a commercial product. Key findings The gelatin microcapsule at a weight ratio for itraconazole/gelatin/citric acid of 1 : 3 : 0.3 was spherical in shape with a smooth surface and inner hole, and gave a maximum drug solubility of about 700 μg/ml. The gelatin microcapsule dramatically increased the initial dissolution rate of itraconazole compared with a commercial product in simulated gastric fluids (pH 1.2). Moreover, at the same dose as the commercial product, it gave significantly higher initial plasma concentrations, C_max and AUC of itraconazole in rats than did the commercial product, indicating that providing the drug in the gelatin microcapsule caused enhanced absorption in rats. At half dose, it gave similar AUC, C_max and T_max values to the commercial product, suggesting that it was bioequivalent to the commercial product in rats. Conclusions The itraconazole‐loaded gelatin microcapsule without ethanol developed using a spray‐drying technique at half the dose of the commercial product can deliver itraconazole in a pattern that allows fast absorption in the initial phase, making it bioequivalent to the commercial product.     

Rapidly absorbed solid oral formulations of ibuprofen using water-soluble gelatin

Rapidly absorbed oral dosage forms of ibuprofen using water-soluble gelatin (hydrolysate of common gelatin: mean mol. wt: 6000) have been studied and compared with tablets prepared with common gelatin (mean mol. wt: 100,000) and commercial tablets. Spray-dried and speed-kneaded powders, two types of granules and tablets were prepared with water-soluble gelatin. The in-vitro dissolution rates of water-soluble gelatin preparations were significantly faster than those of commercial tablets, whereas the tablets prepared using common gelatin had slower dissolution rates than commercial tablets. Water-soluble gelatin enhanced the dissolution rate of ibuprofen by improving the wettability of the drug particle surface by water, without any interaction in solution and the solid state. The absorption behaviour of various preparations was evaluated in four beagle dogs. The peak concentration time (tmax) of the water-soluble gelatin preparations was significantly shorter than that of tablets prepared with common gelatin and commercial tablets. The maximum concentration (cmax) and the area under the serum concentration-time curve (AUCo-10 h) were similar in all cases. The serum concentration profiles of water-soluble gelatin solid preparations were almost the same as those of the solutions. On the other hand, the profiles of the common gelatin tablets were similar to those of the commercial tablets. The mean absorption time (MAT) from water-soluble gelatin preparations was about 0.7 h, while the MAT from commercial tablets and common gelatin tablets was about 1.2 h. The differences in the MAT of water-soluble gelatin preparations and commercial tablets or common gelatin tablets were the same as the differences in mean dissolution time (MDT) in gastrointestinal fluid.(ABSTRACT TRUNCATED AT 250 WORDS)     

Development of novel ibuprofen-loaded solid dispersion with enhanced bioavailability using cycloamylose

To develop a novel ibuprofen-loaded solid dispersion with enhanced bioavailability using cycloamylose, it was prepared using spray-drying techniques with cycloamylose at a weight ratio of 1:1. The effect of cycloamylose on aqueous solubility of ibuprofen was investigated. The physicochemical properties of solid dispersions were investigated using scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and X-ray diffraction. The dissolution and bioavailability in rats were evaluated compared with ibuprofen powder. This ibuprofen-loaded solid dispersion improved about 14-fold drug solubility. Ibuprofen was present in an unchanged crystalline state, and cycloamylose played the simple role of a solubilizing agent in this solid dispersion. Moreover, the dispersion gave 2-fold higher AUC (area under the drug concentration-time curve) value compared with a ibuprofen powder, indicating that it improved the oral bioavailability of ibuprofen in rats. Thus, the solid dispersion may be useful to deliver ibuprofen with enhanced bioavailability without crystalline change.     

Encapsulation of chlorothiazide in whey proteins: effects of wall-to-core ratio and cross-linking conditions on microcapsule properties and drug release

A model drug with limited water-solubility, chlorothiazide, was successfully encapsulated in whey protein-based wall systems cross-linked by glutaraldehyde-saturated toluene via an organic phase. The effects of drug content of the core-in-wall suspension and of cross-linking conditions on core retention and on microcapsule size, structure and core release properties were investigated. Spherical, surface cracks-free microcapsules ranging in diameter from approximately 200-1300 microm were obtained. Particle size distribution of microcapsules was affected by core content and cross-linking conditions. Core retention in microcapsules prepared at different cross-linking conditions and different wall-to-core ratios ranged from 48.9-81%, from 42.2-76.1% and from 37.3-67.2% in large (L), medium-size (M) and small (S) microcapsules, respectively. In all cases, drug crystals were physically entrapped and embedded throughout the cross-linked protein matrix. Core release from the microcapsules into enzyme-free simulated gastric fluid was governed by a diffusion-controlled mechanism and did not involve erosion or softening of the wall matrix. Rate of core release was significantly affected by a combined influence of core content, microcapsule size and cross-linking density. Complete core release from L, M and S microcapsule prepared at different wall-to-core ratios and cross-linking conditions ranged from 28.6-81.2 h, from 16.8-28.6 h and from 7.2-15.9 h, respectively. Results suggested that whey protein-based wall matrix cross-linked by GAST may provide significant opportunities in modulating the release of an encapsulated core with a limited water solubility.     

番茄红素微囊的体内外药剂学行为

目的考察番茄红素微囊的体外释放、番茄红素原料及番茄红素微囊在家犬体内的药代动力学、体外释放和体内吸收的相关性。方法用分光光度法测定释放介质中番茄红素的含量。用HPLC法测定家犬体内的番茄红素含量，数据用3P87程序处理，得到各主要药代动力学参数。体内吸收与体外释放进行点点相关。结果微囊体外释放呈肠溶性，原料及番茄红素微囊的T_1/2α分别为7.30和15.06 h；T_1/2β分别为28.10和46.76 h；T_max分别为22.32和41.03 h；AUC_0-∞分别为1.67和2.08 μg·h·L^-1。体内外相关性良好。结论微囊较原料药呈现缓释特征，体内外相关性结果表明可以根据体外释放情况预测体内的吸收。     

Improved solubility and in vitro dissolution of Ibuprofen from poloxamer gel using eutectic mixture with menthol

To improve the solubility and in vitro dissolution of poorly water-soluble ibuprofen with poloxamer and menthol, the effects of menthol and poloxamer 188 on the aqueous solubility of ibuprofen were investigated. The dissolution study of ibuprofen delivered by poloxamer gels composed of poloxamer 188 and menthol were performed. In the absence of poloxamer, the solubility of ibuprofen increased until the ratio of menthol to ibuprofen increased from 0:10 to 4:6, followed by an abrupt decrease in solubility above the ratio of 4:6, indicating that 4 parts of ibuprofen formed eutectic mixture with 6 parts of menthol. In the presence of poloxamer 188, the solutions with the same ratio of menthol to ibuprofen showed abrupt increase in the solubility of ibuprofen. Furthermore, the solution with ratio of 4:6 showed more than 2.5- and 6-fold increase in the solubility of ibuprofen compared with that without poloxamer and that without menthol, respectively. The poloxamer gel with menthol/ibuprofen ratio of 1:9 and higher than 15% poloxamer 188 showed the maximum solubility of ibuprofen, 1.2 mg/ml. Menthol improved the dissolution rates of ibuprofen from poloxamer gels. Dissolution mechanism showed that the dissolution rate of ibuprofen from the poloxamer gels without menthol was independent of the time, but the drug might be dissolved from the poloxamer gels with menthol by Fickian diffusion. Thus, the poloxamer gels developed using eutectic mixture with menthol, which gave the improved solubility and dissolution of drug, are potential candidates for ibuprofen-loaded transdermal and rectal delivery system.     

Biodegradable cross-linked albumin microcapsules for embolization

The interfacial polymerization process used in the present study produced individual cross-linked albumin microcapsules, the particle size of which depended on the emulsification stirring rate. The variation in cross-linking agent concentration altered the microcapsule wall properties. As shown by SEM observations, microcapsules prepared with low acyl chloride concentrations presented rippled surfaces, while the surfaces of the microcapsules prepared with high acyl chloride concentrations were smooth. It was then suggested that the membranes of the weakly cross-linked microcapsules consisted of cross-linked and denatured albumin. Embolization experiments in the dog kidney showed that the weakly cross-linked microcapsules were biodegradable within 7 days, whereas the highly cross-linked microcapsules were degraded over more than 14 days and led to prolonged ischaemia. The results of the histological experiments carried out on a further eight dogs supported the previous findings yielded by the angiographical experiments. Moreover, they indicated that no foreign body reaction occurred. The lack of this inflammatory granuloma should be attributed to the rapid biodegradation of the microcapsules which produced reversible ischaemic lesions.     

Polyacrylate resin microcapsules for taste masking of antibiotics

Abstract

Various microencapsulated dosage forms were prepared to limit the release of an antibiotic in solution for up to 3 days and in the oral cavity following per oral administration. An experimental antibiotic, clarithromycin (TE-031), was used in these studies. The drug was first encapsulated in gelatin followed in some cases by crosslinking with glutaraldehyde. The gelatin microcapsules were then coated with acrylic resins (Eudragit®), whose solubility properties vary according to pH. A non-solvent coacervation technique was used to apply the Eudragit resins. It was found that crosslinking the gelatin retarded release of TE-031 somewhat relative to that from uncrosslinked gelatin microcapsules in a 72 h release experiment conducted at room temperature. Coating the gelatin microcapsules with Eudragit resins L100, S100, or E100 slowed the release of TE-031 further still; less TE-031 was released over 72 h from the Eudragit-coated formulations prepared with crosslinked gelatin compared with formulations prepared with uncrosslinked gelatin. The Eudragit ElOO-coated crosslinked gelatin microcapsule formulation was most effective in preventing release of the TE-031 under simulated conditions of storage in an aqueous solution.     

Polyacrylate resin microcapsules for taste masking of antibiotics.

Various microencapsulated dosage forms were prepared to limit the release of an antibiotic in solution for up to 3 days and in the oral cavity following per oral administration. An experimental antibiotic, clarithromycin (TE-031), was used in these studies. The drug was first encapsulated in gelatin followed in some cases by crosslinking with glutaraldehyde. The gelatin microcapsules were then coated with acrylic resins (Eudragit), whose solubility properties vary according to pH. A non-solvent coacervation technique was used to apply the Eudragit resins. It was found that crosslinking the gelatin retarded release of TE-031 somewhat relative to that from uncrosslinked gelatin microcapsules in a 72h release experiment conducted at room temperature. Coating the gelatin microcapsules with Eudragit resins L100, S100, or E100 slowed the release of TE-031 further still; less TE-031 was released over 72 h from the Eudragit-coated formulations prepared with crosslinked gelatin compared with formulations prepared with uncrosslinked gelatin. The Eudragit E100-coated crosslinked gelatin microcapsule formulation was most effective in preventing release of the TE-031 under simulated conditions of storage in an aqueous solution.     

Microencapsulation of theophylline in composite wall system consisting of whey proteins and lipids

Theophylline was microencapsulated in composite whey protein-based wall systems containing different proportions of dispersed apolar filler, anhydrous milkfat. Wall emulsions exhibited uni-modal particle size distribution and had a mean particle size of 0.36-0.38 microm. Microcapsules were cross-linked by glutaraldehyde-saturated toluene via an organic phase. Spherical microcapsules ranging in diameter from 150 to larger than 700 microm were obtained and exhibited some surface cracks that could be attributed to the fragile nature of a peripheral, highly cross-linked 'shell' layer around the capsules. Core content ranged from 46.9-56.6% (w/w) and filler content ranged from 12.0-33.4% (w/w). Core and filler retention during microencapsulation ranged from 84.9-96.9%) and from 85.1-89.6%, respectively. Core retention was proportionally related to the proportion of filler embedded in the wall matrix. Core release into SGF and SIF was affected by microcapsule size, type of dissolution medium and wall composition. Rate of core release was inversely proportional to filler content of the wall matrix. This could be attributed to effects of filler content on diffusion through the wall matrix and probably on swelling properties of microcapsules. Results indicated that incorporation of apolar filler in wall matrix of whey protein-based capsules provided the means to enhance retention of a water-soluble core during the microencapsulation process and to decrease the rate of core release into aqueous dissolution media.     

Effect of cross-linking on the in vitro release kinetics of doxorubicin from gelatin implants

Doxorubicin is one of the most potent anti-tumor agents used generally in the treatment of bone cancer. Like other cancer chemotharepeutics, it produces undesirable side effects such as cardiotoxicity, which is especially severe when administrated via the conventional intravenous route. In order to minimize the systemic toxicities and to make this drug more suitable for the treatment of bone cancer, an implantable delivery system with cross-linked gelatin as the biodegradable matrix material was developed. This delivery system could possibly improve targeting of the drug as well as sustain the rate of release of the drug to the tumor. Glutaraldehyde was used as a cross-linking agent. Incorporation of glutaraldehyde in the matrix was needed to maintain the mechanical strength of the implant and to sustain the rate of release of the drug from the implant. Besides cross-linking the gelatin matrix, glutaraldehyde was found to cross-link the free amino group of doxorubicin. The effect of cross-linker concentration on the stability of the drug in the implant and on the rate and extent of release were also evaluated. In conclusion, cross-linked gelatin implants were developed for the local delivery of doxorubicin.     

The prolongation of the in vitro dissolution of a soluble drug (phenethicillin potassium) by microencapsulation with ethyl cellulose

Microcapsules of phenethicillin potassium as a model water-soluble drug, coated with ethyl cellulose, have been prepared (core: wall ratios 1:1, 1:2 and 1:3) in which the taste has been masked, the odour almost eliminated and the release retarded. Sieve analysis showed that with decreasing core: wall ratios there was a trend towards increasing amounts of larger sized microcapsules. At constant core: wall ratios in vitro release of drug was generally greatest from the larger microcapsules. This result correlated with the surface areas of the microcapsules which became less as the asymmetry of the microcapsules diminished with decrease in microcapsule size. There was a linear relation between the amount of ethyl cellulose and the time for 60% release of drug, and the release pattern was analogous to that from insoluble porous matrices. Scanning electron micrographs showed the microcapsules to be irregularly shaped with circular surface pores, and they did not alter in shape or size during dissolution. Tableting of 1:1 core: wall ratio microcapsules significantly further retarded the dissolution.     

Microencapsulation of theophylline in composite wall system consisting of whey proteins and lipids

Theophylline was microencapsulated in composite whey protein-based wall systems containing different proportions of dispersed apolar filler, anhydrous milkfat. Wall emulsions exhibited uni-modal particle size distribution and had a mean particle size of 0.36-0.38 µm. Microcapsules were cross-linked by glutaraldehyde-saturated toluene via an organic phase. Spherical microcapsules ranging in diameter from 150 to larger than 700 µm were obtained and exhibited some surface cracks that could be attributed to the fragile nature of a peripheral, highly cross-linked 'shell' layer around the capsules. Core content ranged from 46.9-56.6% (w/w) and filler content ranged from 12.0-33.4% (w/w). Core and filler retention during microencapsulation ranged from 84.9-96.9% and from 85.1-89.6%, respectively. Core retention was proportionally related to the proportion of filler embedded in the wall matrix. Core release into SGF and SIF was affected by microcapsule size, type of dissolution medium and wall composition. Rate of core release was inversely proportional to filler content of the wall matrix. This could be attributed to effects of filler content on diffusion through the wall matrix and probably on swelling properties of microcapsules. Results indicated that incorporation of apolar filler in wall matrix of whey protein-based capsules provided the means to enhance retention of a water-soluble core during the microencapsulation process and to decrease the rate of core release into aqueous dissolution media.     

The Use of Gelatin Microparticles to Delay the Release of Readily Water-soluble Materials

The adsorption of D-arabinose onto gelatin microparticles demonstrated a Langmuirian adsorption pattern. Evaluation of the dissolution behaviour of D-arabinose-loaded gelatin microparticles suggested that the saccharide, loaded at a level below the adsorption saturation level, was released uniformly over a 14-h period after the loaded gelatin microparticles had been lyophilized for a second time. When dissolution curves were corrected for the initial burst effect seen after the gelatin microparticles had been loaded at higher levels of D-arabinose and lyophilized, steady-state release rates were also evident over prolonged periods. In addition, it was evident that the D-arabinose was adsorbed onto internal surfaces of the hydrated gelatin matrix. Calculation of this internal surface demonstrated the influence of the concentration of the glutaraldehyde used as a cross-linking agent and this parameter, in turn, influenced both the adsorption maxima and the subsequent equilibrium release rates. Application of this data base to a highly water-soluble complex polysaccharide antineoplastic agent, which has a higher molecular weight (22·4 kDa vs 150 Da), demonstrated similar behaviour in that a near zero-order release pattern over at least 16 h could be obtained by attention to the conditions under which the gelatin microparticles were made and subsequently loaded before lyophilization.     

Encapsulation of ethanol by spray drying technique: effects of sodium lauryl sulfate.

Microcapsules composed of ethanol, water and dextrin as a water-soluble polymer can be used to encapsulate poorly water-soluble drugs by spray drying technique. For the encapsulation of a high dose of poorly water-soluble drugs, large amounts of ethanol and consequently large quantities of dextrin are needed for the dissolution of drug and the encapsulation of ethanol, respectively. In order to increase the ethanol content with the decreased amount of dextrin, sodium lauryl sulfate (SLS) was employed in the preparation of microcapsules without drug by a spray drying method. Phase diagrams were prepared to determine the region of microcapsule formation with a three-component system of ethanol, dextrin and water. The homogeneous phase indicated in the phase diagram was used to prepare the alcoholic microcapsules since this phase was not separated rapidly and not too viscous to be spray-dried. Interestingly, SLS at concentrations below 2% remarkably increased both the ethanol content and the encapsulation efficiency of ethanol. The maximum ethanol content and encapsulation efficiency were observed with 0.5-1% of SLS (35.4 and 67.6%, respectively). Furthermore, the increase by SLS was more pronounced at the low dextrin/water ratios than at the high dextrin/water ratios. In particular, the ethanol content and the encapsulation efficiency with the dextrin/ethanol/water ratio of 0.4/1/1, which had relatively small amounts of dextrin, were about ten times higher in the presence of SLS than those without SLS. In conclusion, this study shows that small amounts of SLS can increase the ethanol content and the encapsulation efficiency of ethanol, and allow the reduction in the amount of dextrin required to encapsulate ethanol in the preparation of microcapsules. These findings suggest that the use of SLS may permit the effective encapsulation of high dose of water-insoluble drug into microcapsules.     

改善难溶性药物功效的一种新型给药系统——干酏剂的研究进展

干酏剂是一种将乙醇和药物同时包裹入水溶性聚合物壳内的固态微囊.乙醇的潜溶剂作用及喷雾干燥工艺可能产生的无定形药物,有利于包裹于干酏剂中的水难溶性药物快速分散并溶解于水性介质中,从而提高其溶出速率和生物利用度.本文综合近年来干酏剂研究的主要文献,从干酏剂的制剂成型工艺及机制、对难溶性药物体外溶出、体内吸收及生物利用度的影响,以及基于干酏剂的剂型设计及应用做一综述.