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1.
Due to its low water solubility and slow dissolution rate, genipin was micronized by an antisolvent precipitation process using ethanol as solvent and n‐hexane as antisolvent. The effects of various experimental parameters on the mean particle size (MPS) of micronized genipin were investigated. By analysis of variance, only the concentration of the genipin solution has a significant effect on the MPS in genipin micronization. Under the optimum conditions, micronized genipin with an MPS of 1.8 μm was obtained. The micronized genipin was characterized by various methods, e.g., scanning electron microscopy and thermogravimetry. The analysis results indicated that the chemical structure of micronized genipin was not changed, but the crystallinity was reduced. The dissolution rate and solubility of the micronized genipin were 2.08 and 1.64 times that of the raw drug. In addition, the residual amounts of n‐hexane and ethanol were less than the International Conference on Harmonization limit for solvents. 相似文献
2.
S Zu L Yang J Huang C Ma W Wang C Zhao Y Zu 《International journal of molecular sciences》2012,13(7):8869-8881
The aim of this study was to prepare micronized taxifolin powder using the supercritical antisolvent precipitation process to improve the dissolution rate of taxifolin. Ethanol was used as solvent and carbon dioxide was used as an antisolvent. The effects of process parameters, such as temperature (35-65 °C), pressure (10-25 MPa), solution flow rate (3-6 mL/min) and concentration of the liquid solution (5-20 mg/mL) on the precipitate crystals were investigated. With a lower temperature, a stronger pressure and a lower concentration of the liquid solution, the size of crystals decreased. The precipitation temperature, pressure and concentration of taxifolin solution had a significant effect. However, the solution flow rate had a negligible effect. It was concluded that the physicochemical properties and dissolution rate of crystalline taxifolin could be improved by physical modification such as particle size reduction using the supercritical antisolvent (SAS) process. Further, the SAS process was a powerful methodology for improving the physicochemical properties and radical scavenging activity of taxifolin. 相似文献
3.
Irbesartan‐loaded electrospun nanofibers‐based PVP K90 for the drug dissolution improvement: Fabrication,in vitro performance assessment,and in vivo evaluation
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Ehsan Adeli 《应用聚合物科学杂志》2015,132(27)
Irbesartan with a low bioavailability is known as a poorly water‐soluble drug. The purpose of this investigation is the improvement of physicochemical properties (such as solubility and dissolution rate) of Irbesartan using electrospun nanofibers‐based solid dispersion preparation. Nanofibers were prepared using certain weight ratios of the drug and polyvinylpyrrolidone K90 (PVP K90). Then, dissolution studies were carried out. Moreover, selected samples were examined by many different tests such as Fourier transform infra red (FTIR), differential scanning calorimetry (DSC), X‐ray diffraction (XRD), high‐performance liquid chromatography (HPLC), and scanning electron microscopy (SEM). Though solubility and dissolution rate of all Irbesartan‐PVP nanofibers improved, but the best result was obtained through of ENSD5 (3% (w/v) : 7% (w/v)). In sink condition approximately 97% of this sample was released during 60 min. The drug content was among the different batches from 40.55 ± 1.01 to 245.32 ± 1.77 μg/mL. The maximum saturation solubility was belonged to this sample. According to the results of the thermal analysis and FTIR spectroscopy, there is no chemical reaction between drug and carrier, also samples has not changed during the process. Amorphous structure for nanofibers was confirmed by DSC thermograms and XRD diffractograms and morphological structure of samples were observed by SEM images. Ultimately, in vivo studies were performed in healthy grey rabbits and the results were satisfactory. The drug–polymer nanofibers showed an increase in relative bioavailability than the plain Irbesartan suspension. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42212. 相似文献
4.
采用反溶剂重结晶法进行了青蒿素超细粉体的制备研究。以乙醇为溶剂,水为反溶剂,系统考察了药用辅料类型、反溶剂溶剂体积比、药物溶液浓度和混合强度对产品颗粒形貌和大小的影响。结果表明,辅料羟丙甲纤维素(HPMC)与聚乙烯吡咯烷酮 (PVP)联用可有效控制颗粒形貌,反溶剂溶剂体积比为20,青蒿素乙醇溶液浓度为20 mg·ml-1,搅拌转速为8000 r·min-1时,浆料中可得到平均短径0.84 μm、长径3 μm的针状颗粒,此浆料经喷雾干燥可得到粒径为2~3 μm的类球形粉体颗粒。进一步采用红外光谱、X射线衍射、差热分析、比表面积测试对原料药及产品的特性进行了表征,结果显示,青蒿素经反溶剂重结晶过程与辅料HPMC间产生一定的氢键作用,超细粉体产品的结晶度及熔点降低,比表面积增至原料药的26.4倍。体外溶出测试结果表明,青蒿素超细粉体的溶出速率远优于原料药,超细药物粉体15 min即可溶出88.3%,而同期原料药的溶出度仅为2.1%。 相似文献
5.
Jatinder Kaur Vandana P. Arya Gurvinder Kaur Tusharkanti Raychaudhuri Prem Lata 《Propellants, Explosives, Pyrotechnics》2012,37(6):662-669
The paper presents and compares two methods for the synthesis of fine particles of the high explosives HNS and HMX by ultrasonic treatment and solvent/antisolvent crystallization. The effect of ultrasonic treatment on the particle size of explosives was studied by varying the amplitude and frequency of ultrasonication for different time periods using an ultrasonic probe and an ultrasonic bath. Solvent/antisolvent recrystallization was performed by varying the process parameters including stirring rate, antisolvent temperature etc. In addition to FT‐IR spectroscopy and thermal analysis by TGA/DSC; the particle size and shape of fine powders of the explosives HMX and HNS were determined using particle size analysis and scanning electron microscopy (SEM). Ultrasonic treatment of the probes resulted in the finer grains of HMX compared to solvent‐antisolvent crystallization. However in the case of HNS, solvent‐antisolvent crystallization produced finer particles compared to ultrasonication. 相似文献
6.
纤维素在离子液体中的溶解特性研究 总被引:2,自引:0,他引:2
测定了纤维素在不同结构的离子液体——1-烯丙基-3-甲基咪唑氯化物([AMIM]Cl)和1-丁基-3-甲基咪唑氯化物([BMIM]Cl)中的溶解度和溶解速率。结果发现:相同条件下,纤维素在[AMIM]Cl中具有较大的溶解度和较快的溶解速率;随着纤维素聚合度的增大,相同条件下,纤维素在离子液体中的溶解度降低。进一步通过WXRD、FT-IR、13C NMR和黏度法分析了溶解前后纤维素的化学结构、结晶结构和聚合度,结果表明:纤维素在离子液体中的溶解属于直接溶解,纤维素经离子液体溶解和再生后,晶型由纤维素I转变为纤维素II;溶解时间和温度对再生纤维素的聚合度有较大的影响,随着溶解时间的延长和溶解温度的提高,再生纤维素聚合度降低。 相似文献
7.
The purpose of this study was to prepare, characterize, and evaluate genistein‐containing microparticles with enhanced dissolution profile using poly(ethylene glycol) (PEG) as polymer matrix. Genistein loaded microparticles were prepared by a solvent evaporation process and their surface, thermal, chemical, and dissolution properties were analyzed by microscopy, differential scanning calorimetry, ATR‐FTIR spectroscopy, and USP dissolution apparatus II, respectively. The wettability index was also determined. Genistein exhibited an elongated crystal habit. However, the drug containing PEG microparticles were discrete and quasispherical. The ATR‐FTIR studies performed on the formulation suggested hydrogen bonding between the drug and the polymer matrix. Thermal analysis indicated a conversion of the crystalline form of the drug to an amorphous form. Genistein, exhibiting low solubility and high permeability, is a Class II drug of the Biopharmaceutical Classification Scheme. However, there was a ~9‐fold increase in the rate of dissolution of genistein in the case of all formulations as compared to native genistein. This study showed that genistein could be effectively encapsulated into PEG microparticles using an emulsion‐solvent evaporation technique, therefore avoiding the potential disadvantages of other solid dispersion techniques. This approach provided a significant enhancement in the drug dissolution profile. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2070–2078, 2006 相似文献
8.
Xiaonan Zhang Xiuhua Zhao Yuangang Zu Xiaoqiang Chen Qi Lu Yuliang Ma Lei Yang 《International journal of molecular sciences》2012,13(10):12598-12607
The objective of the study was to prepare vinblastine microparticles by supercritical antisolvent process using N-methyl-2-pyrrolidone as solvent and carbon dioxide as antisolvent and evaluate its physicochemical properties. The effects of four process variables, pressure, temperature, drug concentration and drug solution flow rate, on drug particle formation during the supercritical antisolvent process, were investigated. Particles with a mean particle size of 121 ± 5.3 nm were obtained under the optimized process conditions (precipitation temperature 60 °C, precipitation pressure 25 MPa, vinblastine concentration 2.50 mg/mL and vinblastine solution flow rate 6.7 mL/min). The vinblastine was characterized by scanning electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, mass spectrometry and dissolution test. It was concluded that physicochemical properties of crystalline vinblastine could be improved by physical modification, such as particle size reduction and generation of amorphous state using the supercritical antisolvent process. Furthermore, the supercritical antisolvent process was a powerful methodology for improving the physicochemical properties of vinblastine. 相似文献
9.
Yousef Bakhbakhi Mohammad Asif Achmad Chafidz Abdelhamid Ajbar 《Polymer Engineering and Science》2013,53(3):564-570
The supercritical antisolvent (SAS) precipitation process as a “green” alternative to specialty particles recrystallization was successfully used to generate poly(L ‐lactide) acid (L‐PLA) from dichloromethane (DCM) solution using CO2 as antisolvent. The influence of main operating parameters on the synthesis of L‐PLA particles in the SAS process was methodically examined. In particular, antisolvent addition rate (30, 40, 50, and 60 g/min), temperature (35, 40°C, 45°C, and 50°C), solute concentration (50, 75, 100, and 150 mg/10 ml), and solution addition rate (1, 2.5, 5, and 7.5 ml/min). These parameters could be tuned to give a mean particle diameter of 0.62 μm. It was found using scanning electron microscopy and laser diffraction that increasing the antisolvent addition rate and the solution addition rate, while decreasing the temperature and solute concentration, led to a decrease in the L‐PLA mean particle diameter. Furthermore, a unimodal particle size distribution was obtained at the higher solution and antisolvent addition rates. Spherical‐like primary particles have been obtained in all the experimental runs; thus, no change of particle morphology with the process parameters has been noticed. These results manifested that SAS recrystallization process is a valuable technique to generate reproducibly polymer particles with controlled size and size distribution. POLYM. ENG. SCI. 2013. © 2012 Society of Plastics Engineers 相似文献
10.
Nuno F. da Costa Rolf Daniels Ana I. Fernandes Joo F. Pinto 《International journal of molecular sciences》2022,23(18)
The preparation of amorphous and co-amorphous systems (CAMs) effectively addresses the solubility and bioavailability issues of poorly water-soluble chemical entities. However, stress conditions imposed during common pharmaceutical processing (e.g., tableting) may cause the recrystallization of the systems, warranting close stability monitoring throughout production. This work aimed at assessing the water and heat stability of amorphous olanzapine (OLZ) and OLZ-CAMs when subject to wet granulation and pelletization. Starting materials and products were characterized using calorimetry, diffractometry and spectroscopy, and their performance behavior was evaluated by dissolution testing. The results indicated that amorphous OLZ was reconverted back to a crystalline state after exposure to water and heat; conversely, OLZ-CAMs stabilized with saccharin (SAC), a sulfonic acid, did not show any significant loss of the amorphous content, confirming the higher stability of OLZ in the CAM. Besides resistance under the processing conditions of the dosage forms considered, OLZ-CAMs presented a higher solubility and dissolution rate than the respective crystalline counterpart. Furthermore, in situ co-amorphization of OLZ and SAC during granule production with high fractions of water unveils the possibility of reducing production steps and associated costs. 相似文献
11.
Because of low aqueous solubility and slow dissolution rate, cantharidin has a low oral bioavailability. Our research aims to prepare the inclusion complex of cantharidin and β‐cyclodextrin (β‐CD) and accomplish characterization, in vitro and in vivo evaluation. CA‐β‐CD inclusion complex was prepared by saturated solution method. The CA was demonstrated by HPLC in vitro experiment and by GC‐MS in vivo experiment. CA‐β‐CD inclusion complex was characterized by differential scanning calorimetry (DSC), X‐ray diffractometry (XRD), and nuclear magnetic resonance (NMR). Through complexation with β‐CD, the solubility of CA in neutral aqueous solution was improved significantly. CA‐β‐CD inclusion complex also shows a significantly improved dissolution rate in comparison with free CA. Comparison of the pharmacokinetics between CA‐β‐CD inclusion complex and free CA was performed in rats. The in vivo results show that CA‐β‐CD inclusion complex has earlier tmax, higher Cmax, and higher bioavailability than free CA after oral dosing. By comparing the AUC0–t of CA and CA‐β‐CD inclusion complex, the relative bioavailability of CA‐β‐CD inclusion complex to free CA was 506.3%, which highlighted the evidence of significantly improved bioavailability of formulation of CA with β‐CD. Thus, this β‐CD‐based drug delivery system should be an effective oral dosage form to improve oral bioavailability of CA. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
12.
Antisolvents increase the supersaturation in the crystallization process which can enhance the product yield. The effect of an antisolvent on the solubility of γ-DL-methionine (γ-DL-met) in aqueous solution was investigated. The solubility of γ-DL-met was measured with various binary solvent mixtures. It improved with higher temperature but decreased with increasing the antisolvent mass fraction. Acetone showed the highest efficiency to reduce the solubility. The solubilities were correlated with the van't Hoff-Jouyban-Acree model and the modified Apelblat-Jouyban-Acree model. Both models fitted to the experimental results with high accuracy. Enthalpy, entropy, and Gibbs free energy of dissolution were determined by van't Hoff analysis. The thermodynamic properties indicated that the dissolution process is endothermic and entropy-driven. 相似文献
13.
《分离科学与技术》2012,47(12):2645-2660
Abstract Three sulfa drugs (sulfathiazole, sulfamethizole, and sulfabenzamide) were crystallized using carbon dioxide and water as antisolvents, and the effects of the type of solvent, the crystallization temperature, and the antisolvent injection rate were investigated. Sulfathiazole crystallized in granulate form from acetone, but it was crystallized in acicular form from methanol. Sulfamethizole was crystallized in tabulate form from acetone and as plates from DMF. Sulfabenzamide was precipitated in the form of prisms from acetone and of aciculates from ethyl acetate. As the crystallization temperature increased from 30 to 50°C, the average particle size increased from 6.5 to 10.5 µm for sulfathiazole, 29.5 to 53.1 µm for sulfamethizole, and 33.0 to 59.8 µm for sulfabenzamide. The crystal habit tended to become more needle‐like as the antisolvent injection rate increased. Larger particles were produced when the antisolvent was changed from carbon dioxide to water. 相似文献
14.
Solution‐mediated polymorphic transformation (SMPT) of the metastable polymorph B of L‐histidine (L‐his) into the stable polymorph A in water‐antisolvent solutions was performed. Methanol, acetone, and acetonitrile served as antisolvents. The SMPT was studied via nucleated batch antisolvent crystallization process by determining the change of the fraction of the stable polymorph A of L‐his in the crystal phase with time during the crystallization process. The fraction of the stable polymorph A of L‐his was assessed offline by Raman spectroscopy. The transformation time depended on the fractions of form A obtained at the initial stage of crystallization. The transformation rate of the metastable polymorph B into the stable polymorph A at lower antisolvent volume fraction was faster than at higher antisolvent volume fraction. The transformation time of polymorph B into polymorph A in water‐acetonitrile solution was the shortest compared to the other solutions. 相似文献
15.
Ana Casas María Virginia Alonso Mercedes Oliet Ester Rojo Francisco Rodríguez 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2012,87(4):472-480
BACKGROUND: The dissolution of wood and the regeneration of compounds such as cellulose and lignin is one of the challenges currently facing biorefineries. Lignin can be processed and employed for value‐added products; therefore, environmentally friendly methods for wood solubilization and lignin regeneration are required and ionic liquids (ILs) offer an attractive alternative approach. RESULTS: Dissolution of Pinus radiata and Eucalyptus globulus woods in imidazolium‐based ILs (1‐butyl‐3‐methylimidazolium acetate, 1‐ethyl‐3‐methylimidazolium acetate and 1‐ethyl‐3‐methylimidazolium chloride) was studied as well as the regeneration of lignin from wood liquors. The dissolution of wood in ILs was verified using an optical microscope to select the most appropriate ILs and the best experimental time and temperature conditions. Lignin was regenerated from wood dissolved in 1‐ethyl‐3‐methylimidazolium chloride after 24 h at 150 °C by precipitation with an antisolvent. The regenerated solid was analyzed by Fourier transform infrared spectroscopy and compared with Indulin AT (reference). Furthermore, the influence of the wood dissolution time, the antisolvent employed and the antisolvent/wood solution ratio in the lignin recovery was studied. CONCLUSIONS: The current study shows that 1‐ethyl‐3‐methylimidazolium chloride can be employed effectively to dissolve wood at 150 °C for 24 h and lignin can be regenerated using methanol or ethanol as antisolvents. Copyright © 2012 Society of Chemical Industry 相似文献
16.
Jatinder Kaur Vandana P. Arya Gurvinder Kaur Yashpal P. Gupta Manmohan M. Verma Prem Lata 《Propellants, Explosives, Pyrotechnics》2010,35(5):487-493
Solvent–antisolvent recrystallization employed for size reduction of HNS has been described and the effect of various parameters such as stirring rate, effect of antisolvent type, antisolvent temperature, ultrasonication, etc. was investigated. Purified HNS, produced by hot solvent recrystallization of production grade crude HNS, of mean particle size ∼95 μm was used for preparation of ultrafine particles of HNS. Solvent contamination in terms of residual solvent was determined by 1H NMR and GC‐MS analysis. In addition, ultrafine HNS has been characterized for purity (HPLC, 1H NMR), particle size and shape (PSA and SEM), specific surface area (BET analysis), thermal behavior (TGA, DSC), sensitivity (impact, friction), etc. The results have been compared with C‐HNS. UF‐HNS was >99% pure with mean particle size <1 μm. SEM showed submicrometer size rods like particles of HNS as the final material. 相似文献
17.
Muhammad Inam Lu Liu Jian-Wei Wang Ka-Xi Yu Chi-Uyen Phan Jie Shen Wen-Hua Zhang Guping Tang Xiurong Hu 《International journal of molecular sciences》2021,22(2)
Puerarin (PUE) is a Chinese traditional medicine known to enhance glucose uptake into the insulin cells to downregulate the blood glucose levels in the treatment of type II diabetes. Nevertheless, the bioavailability of pristine PUE is limited due to its poor solubility and low intestinal permeability. In this work, we demonstrate that the solubility of PUE can be significantly enhanced via its co-crystallization with L-Proline (PRO). Two crystalline phases, namely, the solvate-free form [PUE][PRO] (I) and the solvated form [PUE]2[PRO]∙EtOH∙(H2O)2 (II) are isolated. These two phases are characterized by single-crystal X-ray diffraction (SCXRD), powder X-ray diffraction (PXRD), Fourier-transformed infrared (FT-IR) spectra, nuclear magnetic resonance (NMR), and thermogravimetric analysis in association with differential scanning calorimetry (TGA-DSC). The solubility and dissolution rate of both I and II in water, gastrointestinal tract at pH 1.2, and phosphate buffer at pH 6.8 indicates a nearly doubled increase as compared to the pristine PUE. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay of pristine PUE, I and II against murine colon cancer cell lines CT-26 and human kidney cell lines HEK-293 indicated that neither compound exhibits obvious cytotoxicity after 24 h. This work showcases that the readily available and biocompatible PRO can be a promising adjuvant to enhance the physicochemical properties of PUE toward orally administered drug formulation with improved pharmacokinetics. 相似文献
18.
Bisphenol‐A polycarbonate (BAPC) was synthesized by solid‐state polymerization (SSP) using a semicrystalline prepolymer crystallized by antisolvent method. The antisolvent crystallization was investigated as a function of antisolvent types using X‐ray diffraction (XRD), different scanning calorimetry (DSC), and scanning electron microscopes (SEM). The results showed antisolvent types had a significant effect on the crystallization of BAPC. Prepolymer induced by acetone as an antisolvent gained a higher crystallinity of 37.0%, more uniform particle size, and mature crystal structure compared with the samples crystallized by methanol and ethanol. Then crystallization of BAPC by acetone was carried out at crystallization temperature in the range of 40–80 °C for 1–5 h. A high crystallinity of 42.0% was acquired with the crystallization conducted at 70 °C for 2 h. Prepolymer with appropriate crystallinity of 37.8% resulted in high‐molecular‐weight polymer of 57,411 via SSP due to the effect of crystallinity and plasticization of residual solvent. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43636. 相似文献
19.
Zhao X Zu Y Jiang R Wang Y Li Y Li Q Zhao D Zu B Zhang B Sun Z Zhang X 《International journal of molecular sciences》2011,12(4):2678-2691
The goal of the present work was to study the feasibility of 10-hydroxycamptothecin (HCPT) nanoparticle preparation using supercritical antisolvent (SAS) precipitation. The influences of various experimental factors on the mean particle size (MPS) of HCPT nanoparticles were investigated. The optimum micronization conditions are determined as follows: HCPT solution concentration 0.5 mg/mL, the flow rate ratio of CO(2) and HCPT solution 19.55, precipitation temperature 35 °C and precipitation pressure 20 MPa. Under the optimum conditions, HCPT nanoparticles with a MPS of 180 ± 20.3 nm were obtained. Moreover, the HCPT nanoparticles obtained were characterized by Scanning electron microscopy, Dynamic light scattering, Fourier-transform infrared spectroscopy, High performance liquid chromatography-mass spectrometry, X-ray diffraction and Differential scanning calorimetry analyses. The physicochemical characterization results showed that the SAS process had not induced degradation of HCPT. Finally, the dissolution rates of HCPT nanoparticles were investigated and the results proved that there is a significant increase in dissolution rate compared to unprocessed HCPT. 相似文献