Résumé
@#Abstract: In order to search for coumarin-based anti-platelet aggregation compounds with high efficacy and good druggability, twenty-five 3-acetyl-7-hydroxy-coumarin oxime derivatives (6a-6y) were synthesized via Vilsmeier-Haack reaction, Knoevenagel reaction, Williamson reaction, electrophilic substitution reaction and oximation reaction from resorcinol. Their structures were confirmed by HRMS and 1H NMR spectra. The anti-platelet aggregation activity of the target compounds was evaluated using Born’s turbidimetric method. The results revealed that most of them could significantly inhibit platelet aggregation induced by adenosine diphosphate (ADP), collagen, arachidonic acid (AA) and thrombin. Among them, the target compounds 6a and 6b not only had strong inhibitory activity on platelet aggregation induced by the four inducers, but also exhibited good water solubility (3.46 mg/mL and 3.85 mg/mL, respectively) and lipid-water partition coefficient (2.56 and 2.85, respectively) and were expected to become a preclinical candidate compound with multi-target action against platelet aggregation.
Résumé
@#Abstract: In this study, structural optimization of borneol was carried out to improve their solubility and promote their further application in stroke therapy. BP-3, a prodrug of borneol, was designed and synthesized based on the principle of phosphate modification. The solubility of BP-3 was determined by evaporative light scattering detector (ELSD), and the degree and speed of drug release were tested in mouse plasma, and the neuroprotective effect of BP-3 was evaluated in mouse model of transient middle cerebral artery occlusion (tMCAO). According to the results, BP-3 was completely soluble in saline at 20 mg/mL; in mouse plasma, approximately 40% of the borneol were released within 2 h; in the tMCAO mouse model, TTC staining showed that BP-3 was effective in reducing the infarct area; Nissl staining showed that BP-3 ameliorated the neuronal injury; the grip and grasping strength tests elucidated that BP-3 reduced the damage of sports ability caused by injury; and the rotating rod test proved that BP-3 could promote the recovery of motor ability in mice. BP-3 has good water solubility, suitable drug release rate and excellent neuroprotective effects, and has broad prospects for drug development.
Résumé
Background: The fact that about 90 % of newly discovered API’s or new molecular entity(NME) have little or no aqueous solubility, causes a significant protest to the initialization of development and their scale up of dosage form in the Pharma Industry. Aqueous solubility of API’s has critical role in drug dissolution or availability of drug at the site of action or bioavailability, when a dosage form is administered orally.Objective: The object of this study is to formulate a modified release tablet dosage form of a poorly aqueous soluble drug, which not only have higher aqueous solubility or bioavailability but also have sustained release characteristics with high mechanical strength &their commercial viability. Numerous techniques are available for the solubility enhancement but all individual techniques have its own limitations for commercialization.Method: Aqueous solubility of drugs is improved by the known Solubility enhancement techniques like Micronization &Solid dispersions. After successful solubility enhancement, sustained release or modified release tablets of poorly aqueous soluble drug can be easily formulated into a suitable shape or size by using a known Polymer Matrix Sintering Technology with commercial feasibility. Micronization of poorly water-soluble drugs can be performed by Air Jet Mill or Ball Mill. Whereas Solid dispersion technique involves, molecular dispersion of poorly soluble drug in a suitable inert carrier, to form an amorphous and highly soluble compounds. Sintering Technology is defined as the bonding of adjacent particle surfaces in a mass of powder, or in compact, by the application of heat. Conventional sintering technique involves the heating of compact at a temperature below the melting point of the solid constituents in a controlled environment under atmospheric pressure.Results: Enhanced solubility of poorly soluble API’s by these proposed techniques is due to either conversion of crystalline compound in to amorphous form or reduction of particle size to its molecular level by the application of Micronization or solid dispersion techniques. The developed modified release tablets will show a sustained release characteristic due to Sintering aspect and provides enhanced solubility of BCS class II or IV drugs.Conclusion: Novel modified release tablets have been designed through consolidation of Solubility enhancement and Polymer Matrix Sintering technologies. Simultaneous exploitation of well-known and established approaches- Micronization (optimum particle size reduction) or solid dispersion, optional surfactant and Polymer Matrix Sintering Technique in the recent concept, produces significant enhancement of solubility of poorly water soluble API’s without compromising the content uniformity of dosage form and also provide a modified or sustained release characteristics with high mechanical strength. The release profile of drug can be easily tailored by using combination of both techniques where challenges of low solubility are prominent.
Résumé
Purpose: Sildenafil citrate is widely used drug for the treatment of Erectile Dysfunction (ED) and Ginseng is a natural aphrodisiac reported to benefit this condition. The objective of the present study was to develop orodispersible tablets (ODTs) containing combination of Sildenafil citrate and Ginseng extract to improve the bioavailability, reduce the dosing frequency and thereby maintaining the therapeutic efficacy of the drug. Methods: The ODTs were prepared using superdisintegrants such as Croscarmellose sodium (CCS), povidone, and sodium starch glycolate (SSG) at varying concentrations (2%, 4% and 6%) by direct compression. The bitter taste of Sildenafil citrate was masked by Doshion resin. The optimized formulation based on least disintegration time (DT) was chosen to reformulate using sublimating agents such as camphor, menthol or thymol at varying concentrations (1%, 2%, 3%) to further reduce the DT. The compatibility of drug with excipients was investigated and the prepared formulations were evaluated for pre and post-compression parameters. Results: The post-compression parameters such as weight variation, hardness, friability, DT and in-vitro drug release was found within specified limit. The formulation with camphor (2%) had DT of 12 sec and drug release >90% within 5 min hence was considered as optimized formulation. The accelerated stability study and kinetics modelling was performed for optimized formulation. Conclusion: The formulated Sildenafil citrate and Ginseng ODT’s were found to be promising formulation with quicker DT and drug release which will eventually have higher bioavailability and better efficacy along with averting the issues of swallowing and improving patient compliance.
Résumé
Objective:To prepare water-soluble graphene-based itraconazole antifungal eye drops and evaluate its antifungal activity against Fusarium solani. Methods:By oxidative modification of graphene and modification of polymer materials, water-soluble graphene oxide-modified polyethylene glycol (GO-PEG) composites were prepared.The composites were characterized by scanning electron microscopy, zeta potential, and Raman spectroscopy.The antifungal drug itraconazole was loaded onto the GO-PEG vector by solvent evaporation method, and itraconazole eye drops were obtained.The drug loading of itraconazole eye drops was measured using a UV and visible spectrophotometer.The antifungal effect in vitro was assessed by the microdilution method and light microscopy. Results:Scanning electron microscopy showed that GO-PEG had a two-dimensional nanosheet structure and many wrinkles.The zeta potential of GO-PEG was -42.40 mV.Raman spectroscopy showed that the ID/ IG of GO-PEG was 1.003.Using the water-soluble GO-PEG vector, a maximum itraconazole concentration of 10 mg/ml was achieved with a 10 000-fold increase in apparent solubility (10 mg/ml vs 0.001 mg/ml). The antifungal results showed that the minimum inhibitory concentration of itraconazole eye drops against Fusarium solani was approximately 1.88 μg/ml, but the GO-PEG vector has no significant antifungal activity against Fusarium solani. Conclusions:GO-PEG achieves effective loading and solubilization of itraconazole, demonstrating an in vitro inhibitory effect on Fusarium solani.
Résumé
Dioscoreae Rhizoma formula granules are made from decoction pieces by decocting, extracting, separating, concentrating, drying and granulating, which have the advantages of simple dispensing, convenient use and easy to take without decoction. However, because Dioscoreae Rhizoma is rich in starch and mucus components, its extract powder and formula granules are poorly soluble and difficult to dissolve or disperse completely within 5 min, and the insoluble material is difficult to dissolve completely even after 24 h in water, which affects the quality evaluation of the formula granules and medication psychology of patients. Therefore, by studying the dissolution process and mechanism of Dioscoreae Rhizoma extract and its formula granules, it was found that the special chemical composition of Dioscoreae Rhizoma, the denaturation of starch and its compounding with protein and other substances during the high temperature extraction process, and the contraction of coating membrane during the spray drying process were combined to form the special microstructure of coating membrane covering starch granules, and it is the root cause of poor solubility of Dioscoreae Rhizoma formula granules. Based on the research on the structure, property and function of the powder, this paper proposed a technical strategy to improve the solubility of Dioscoreae Rhizoma formula granules by powder modification process, and experimentally demonstrated that the modified Dioscoreae Rhizoma formula granules could completely dissolve within 2 min, which solved the technical problem and could provide reference for the improvement of solubility of other similar varieties, and promote the high-quality development of traditional Chinese medicine formula granule industry.
Résumé
OBJECTIVE To optimize the preparation process of Soft-shelled turtle blood lyophilized powder (STBLP), and to provide a reference for improving the availability and quality stability of soft-shelled turtle blood (STB). METHODS STBLP was prepared with vacuum freeze-drying. Taking the solubility as the index, the preparation process parameters of STBLP were optimized by single factor experiment and Box-Behnken response surface method. RESULTS The optimal freeze-drying process for STBLP was obtained: pre-freezing time of 4 h, total drying time of 13 h (before at 0 ℃), and resolution drying temperature of 25 ℃. The average solubility of 3 batches of STBLP prepared according to the optimal process was 95.72% (RSD=0.68%, n=3), the relative error of which was -0.97% to the theoretical solubility (96.66%). CONCLUSIONS Optimized lyophilization process in this study are stable and feasible, the solubility of the prepared sample is high.
Résumé
Ionic liquids(ILs) are salts composed entirely of anions and cations in a liquid state at or near room temperature, which have a variety of good physicochemical properties such as low volatility and high stability. This paper mainly reviewed the research overview of ILs in the application of traditional Chinese medicine(TCM) volatile oil preparation technology. Firstly, it briefly introduced the application of TCM volatile oil preparation technology and composition classification and physicochemical properties of ILs, and then summarized the application of ILs in the extraction, separation, analysis, and preparation of TCM volatile oil. Finally, the problems and challenges of ILs in the application of TCM volatile oil were explained, and the application of ILs in TCM volatile oil in the future was prospected.
Sujets)
Liquides ioniques/composition chimique , Huile essentielle/analyse , Médecine traditionnelle chinoise , Cations , Produits biologiques , TechnologieRésumé
Objective To investigate the solubility and stability of Tetrodotoxin (TTX) in different solvents, and the effect of temperature and pH on its stability. Methods Solutions of TTX in different matrices were prepared. Their concentrations at different temperatures and pH buffers were determined by high performance liquid chromatography and their solubility and stability were analyzed and calculated. Results TTX was most soluble at pH 3.5 and its solubility decreased as the pH increased. TTX degraded most rapidly under strong alkali conditions, with complete degradation after 20 min of reaction at 0.1 mol/L sodium hydroxide and 70 ℃. The stability test results similarly demonstrated that TTX was least stable under alkaline conditions. In a PBS buffered solution at 37 ℃, pH 7.4, TTX concentration began to decrease consistently at 1~10h, with a degradation rate of 88.07±0.27% after 28 days. Conclusion TTX is readily soluble in acidic aqueous solutions at pH 3.5 and almost insoluble in alkaline aqueous solutions. Its stability is closely related to the temperature and pH of the medium. It is more stable in acidic aqueous solutions and easily degrades under alkaline conditions, and its degradation process could be accelerated by increasing temperature.
Résumé
Abstract Development of ceftriaxone loaded nanostructured lipid carriers to increase permeability of ceftriaxone across uninflamed meninges after parenteral administration. Lipids were selected by theoretical and experimental techniques and optimization of NLCs done by response surface methodology using Box-Behnken design. The Δδt for glyceryl monostearate and Capryol90 were 4.39 and 2.92 respectively. The drug had maximum solubility of 0.175% (w/w) in glycerol monostearate and 2.56g of Capryol90 dissolved 10mg of drug. The binary mixture consisted of glyceryl monostearate and Capryol90 in a ratio of 70:30. The optimized NLCs particle size was 130.54nm, polydispersity index 0.28, % entrapment efficiency 44.32%, zeta potential -29.05mV, and % drug loading 8.10%. In vitro permeability of ceftriaxone loaded NLCs was 5.06x10-6 cm/s; evidently, the NLCs pervaded through uninflamed meninges, which, was further confirmed from in vivo biodistribution studies. The ratio of drug concentration between brain and plasma for ceftriaxone loaded NLCs was 0.29 and that for ceftriaxone solution was 0.02. With 44.32% entrapment of the drug in NLCs the biodistribution of ceftriaxone was enhanced 7.9 times compared with that of ceftriaxone solution. DSC and XRD studies revealed formation of imperfect crystalline NLCs. NLCs improved permeability of ceftriaxone through uninflamed meninges resulting in better management of CNS infections.
Sujets)
Ceftriaxone/agonistes , Triage/classification , Lipides/analyse , Diffraction des rayons X/instrumentation , Techniques in vitro/méthodes , Infections du système nerveux central/anatomopathologieRésumé
Abstract Solid dispersions (SDs) of ursolic acid (UA) were developed using polyvinylpyrrolidone K30 (PVP K30) in combination with non-ionic surfactants, such as D-α-tocopherol polyethylene glycol 1000 succinate (TPGS) or poloxamer 407 (P407) with the aim of enhancing solubility and in vitro release of the UA. SDs were investigated using a 24 full factorial design, subsequently the selected formulations were characterized for water solubility, X-ray diffractometry (XRD), differential scanning calorimetry (DSC), particle diameter, scanning electron microscopy, drug content, physical-chemical stability and in vitro release profile. SDs showed higher UA water-solubility than physical mixtures (PMs), which was attributed by transition of the drug from crystalline to amorphous or molecular state in the SDs, as indicated by XRD and DSC analyses. SD1 (with P407) and SD2 (with TPGS) were chosen for further investigation because they had higher drug load. SD1 proved to be more stable than SD2, revealing that P407 contributed to ensure the stability of the UA. Furthermore, SD1 and SD2 increased UA release by diffusion and swelling-controlled transport, following the Weibull model. Thus, solid dispersions obtained with PVP k-30 and P407 proved to be advantageous to enhance aqueous solubility and stability of UA.
Sujets)
Polyéthylène glycols/administration et posologie , Solubilité , Poloxamère/effets indésirables , Diffusion , Rayons X/effets indésirables , Techniques in vitro , Calorimétrie différentielle à balayage/méthodes , Préparations pharmaceutiques/analyse , Microscopie électronique à balayage/méthodesRésumé
@#Beta toxin (CPB) is a lethal toxin and plays a key role in enterotoxemia of ruminants caused by Clostridium perfringens type C strain. The existing vaccines based on crude CPB need time-consuming detoxification and difficult quality control steps. In this study, we synthesized the rCPBm4 of C. perfringens type C strain and small ubiquitin-like modifier (SUMO)-tag CPBm4 (rSUMO-CPBm4) by introducing four amino acid substitutions: R212E, Y266A, L268G, and W275A. Compared with rCPBm4, rSUMO-CPBm4 was expressed with higher solubility in Escherichia coli BL21 (DE3). Neither rCPBm4 nor rSUMO-CPBm4 was lethal to mice. Although rCPBm4 and rSUMO-CPBm4 were reactogenic with polyclonal antibodies against crude CPB, rabbits vaccinated with rSUMO-CPBm4 developed significant levels of toxin-neutralizing antibody (TNA) titers that conferred protection against crude toxin challenge. These data suggest that genetically detoxified rSUMO-CPBm4 is a promising subunit vaccine candidate for C. perfringens type C beta enterotoxemia.
Résumé
Introdução: Cimentos endodônticos à base de silicato de cálcio demonstram maior solubilidade em água destilada. Emprego de metodologias alternativas pode auxiliar em melhor compreensão sobre a solubilidade desses materiais. Objetivo: Avaliar o efeito da solução de imersão e do tipo de modelo experimental na solubilidade de cimento pronto para uso Bio-C Sealer. Material e método: Modelos circulares de polietileno ou dentina bovina (n = 16) foram confeccionados. Após inserção do cimento, os espécimes foram mantidos em estufa a 37 °C por 48 horas. Posteriormente, as amostras foram pesadas em balança de precisão para determinação da massa inicial. Na sequência, os espécimes foram imersos em 7,5 mL de água destilada (pH 6,5) ou PBS (pH 7,0) (n = 8) por 28 dias. Após isso, as amostras foram removidas das soluções e pesadas a cada 24 horas até a estabilização da massa final (0,001g). Corpos de prova confeccionados com Bio-C Sealer foram empregados como controle. A solubilidade foi avaliada de acordo com a diferença entre a massa inicial e final em porcentagem. Teste ANOVA Two-Way e teste post-hoc de Tukey foram realizados (α = 0,05). Resultado: Imersão em água destilada proporcionou maior solubilidade em comparação com PBS, independentemente do modelo experimental (p < 0,05). Corpos de prova apresentaram maior solubilidade, seguidos dos modelos de polietileno e dentina imersos em água destilada (p < 0,05). Não houve diferença entre os modelos experimentais imersos em PBS (p > 0,05). Conclusão: Bio-C Sealer apresenta solubilidade significativamente maior em água destilada do que em PBS em todas condições. Modelo experimental empregando dentina bovina e PBS como solução de imersão demonstra diminuir a perda de massa de Bio-C Sealer e pode ser uma alternativa valiosa para avaliar a solubilidade de cimentos biocerâmicos
Introduction: Calcium silicate-based sealers demonstrate greater solubility in distilled water. The use of alternative methodologies can help at better understanding the solubility of these materials. Objective: To evaluate the effect of the immersion solution and the type of experimental model on the solubility of readyto-use Bio-C Sealer. Material and method: Circular models of polyethylene or bovine dentin (n = 16) were made. After insertion of the sealer, the specimens were kept in an oven at 37°C and 95% humidity for 48h. Subsequently, the samples were weighed on a precision balance to determine the initial mass. Next, the specimens were immersed in 7.5 mL of distilled water (pH 6.5) or PBS (pH 7.0) (n = 8) for 28 days. After that, the samples were removed from the solutions and weighed every 24 hours until the final mass stabilized (0.001g). Test specimens made with Bio-C Sealer were used as a control. Solubility was evaluated according to the difference between the initial and final mass in percentage. Two-Way ANOVA test and Tukey post-hoc tests were performed (α=0.05). Result: Immersion in distilled water provided greater solubility compared to PBS regardless of the experimental model (p<0.05). The test specimens showed greater solubility, followed by polyethylene and dentin models immersed in distilled water (p<0.05). There was no difference between the experimental models immersed in PBS (p>0.05). Conclusion: Bio-C Sealer presents significantly greater solubility in distilled water than in PBS under all conditions. Experimental model using bovine dentin and PBS as an immersion solution demonstrates reduction in the mass loss of Bio-C Sealer and can be a valuable alternative for evaluating the solubility of bioceramic sealers
Sujets)
Bovins , Solubilité , Eau Distillée , Calcarea Silicata , Analyse de variance , Dentine , Phénomènes physiques , Ciments dentairesRésumé
Abstract Oxazolidine derivatives (OxD) have been described as third-line antibiotics and antitumoral agents. The inclusion complexes based on cyclodextrin could improve the solubility and bioavailability of these compounds. A novel synthetic OxD was used, and its inclusion complexes were based on 2-hydroxy-beta-cyclodextrin (2-HPßCD). We conducted an in silico study to evaluate the interaction capacity between OxD and 2-HPßCD. Characterization studies were performed through scanning electron microscopy (SEM), Fourier-transformed infrared (FTIR), nuclear magnetic resonance spectroscopy (1H-NMR), X-ray diffraction (XRD), and thermal analyses. A kinetic study of the OxD was performed, including a cytotoxicity assay using peripheral blood mononuclear cells (PBMCs). The maximum increment of solubility was obtained at 70 mM OxD using 400 mM 2-HPßCD. SEM analyses and FTIR spectra indicated the formation of inclusion complexes. 1H-NMR presented chemical shifts that indicated 1:1 stoichiometry. Different thermal behaviors were obtained. The pharmacokinetic profile showed a short release time. Pure OxD and its inclusion complex did not exhibit cytotoxicity in PBMCs. In silico studies provided a foremost insight into the interactions between OxD and 2-HPßCD, including a higher solubility in water and an average releasing profile without toxicity in normal cells
Sujets)
Solubilité/effets des médicaments et des substances chimiques , Cyclodextrines/agonistes , Microscopie électronique à balayage/méthodes , Spectroscopie par résonance magnétique/méthodes , Spectroscopie infrarouge à transformée de Fourier/méthodes , Spectroscopie par résonance magnétique du proton/méthodes , Antibactériens/analyseRésumé
Abstract Solubility of pharmaceutical drugs in organic solvents is one of the important parameters to understand the equilibrium concentration of solute-solvent, which helps optimize and design crystallization conditions to obtain the desired product crystals. In the present study, Chlorzoxazone (CHZ) is used as a model pharmaceutical compound to investigate the equilibrium solubility, the influence of solvent and the operating conditions on the shape, and the size distribution. The solubility of CHZ is determined in organic solvents like Isopropanol, Ethanol, and 2-Ethoxyethylacetate, Ethylacetate and Ethyllactate using shake flask method from -5ºC to 60ºC. The solubility of CHZ in these solvents shows an increasing trend as the temperature increases in the following order: ethyllactate + water (0.5+0.5) < ethylacetate < isopropanol < ethanol < 2-ethoxyethylacetate < ethyllactate + water (0.75+0.25). The solvents, isopropanol, ethanol, and ethyl lactate, produce needle-shaped crystals, while 2-ethoxyethylacetate and ethyl acetate tend to produce plate shaped crystals. CHZ crystals obtained from 2-ethoxyethylacetate tend to have plate shaped crystals with a lower aspect ratio and are selected for batch cooling crystallization experiments performed at different cooling rates, and agitation. It is found that the agitation at 300 rpm and the cooling rate 0.2ºC/min produce more uniform crystal size distribution
Sujets)
Solvants/classification , Chlorzoxazone/analyse , Cristallisation/classification , Solubilité , Préparations pharmaceutiques/administration et posologieRésumé
This in vitro study evaluated and compared the effects of different polymerization times on the surface microhardness, water sorption, and water solubility of flowable composite resins. Three flowable composite resins [Es Flow (ESF), IGOS Flow (IGF), Estelite Flow Quick (EFQ)] were tested in this study. Each flowable composite resin (n = 7) was polymerized in a disc-shaped mould (1x10 mm) with an LED light-curing unit (D Light Pro) for two different times (20 and 40 sec.). The top surfaces of all specimens were polished (Sof-Lex). The surface microhardnesses of the flowable composite resins were measured with a Vickers HMV microhardness tester. Water sorption and water solubility were calculated according to the ISO 4049 standard. One-way ANOVA and post hoc Tamhane, Dunnett, and Tukey tests were used in the statistical analyses. Pearson's and Spearman's rho correlation tests were used to assess possible correlations between the different variables. The results were evaluated with a significance of p<0.05. In terms of microhardness, a significant difference was found between materials at the same polymerization times (p<0.05). All materials showed water sorption of less than 40 µg/mm3 and water solubility of less than 7.5 µg/mm3 by following ISO 4049. The correlations among surface microhardness, water sorption, and water solubility showed that the differences were determined by the materials and the polymerization times. The physical properties of all flowable composite resin materials were enhanced after polymerization for twice the time recommended by the manufacturers.
Résumé
The powder modification technology was used to improve the powder properties and microstructure of Dioscoreae Rhizoma extract powder, thereby solving the problem of poor solubility of Dioscoreae Rhizoma formula granules. The influence of modifier dosage and grinding time on the solubility of Dioscoreae Rhizoma extract powder was investigated with the solubility as the evaluation index, and the optimal modification process was selected. The particle size, fluidity, specific surface area, and other powder properties of Dioscoreae Rhizoma extract powder before and after modification were compared. At the same time, the changes in the microstructure before and after modification was observed by scanning electron microscope, and the modification principle was explored by combining with multi-light scatterer. The results showed that after adding lactose for powder modification, the solubility of Dioscoreae Rhizoma extract powder was significantly improved. The volume of insoluble substance in the liquid of modified Dioscoreae Rhizoma extract powder obtained by the optimal modification process was reduced from 3.8 mL to 0 mL, and the particles obtained by dry granulation of the modified powder could be completely dissolved within 2 min after being exposed to water, without affecting the content of its indicator components adenosine and allantoin. After modification, the particle size of Dioscoreae Rhizoma extract powder decreased significantly, d_(0.9) decreased from(77.55±4.57) μm to(37.91±0.42) μm, the specific surface area and porosity increased, and the hydrophilicity improved. The main mechanism of improving the solubility of Dioscoreae Rhizoma formula granules was the destruction of the "coating membrane" structure on the surface of starch granules and the dispersion of water-soluble excipients. This study introduced powder modification technology to solve the solubility problem of Dioscoreae Rhizoma formula granules, which provided data support for the improvement of product quality and technical references for the improvement of solubility of other similar varieties.
Sujets)
Poudres , Solubilité , Technologie pharmaceutique , Technologie , Extraits de plantes , Taille de particuleRésumé
This study aims to improve the solubility and bioavailability of daidzein by preparing the β-cyclodextrin-daidzein/PEG_(20000)/Carbomer_(940) nanocrystals. Specifically, the nanocrystals were prepared with daidzein as a model drug, PEG_(20000), Carbomer_(940), and NaOH as a plasticizer, a gelling agent, and a crosslinking agent, respectively. A two-step method was employed to prepare the β-cyclodextrin-daidzein/PEG_(20000)/Carbomer_(940) nanocystals. First, the insoluble drug daidzein was embedded in β-cyclodextrin to form inclusion complexes, which were then encapsulated in the PEG_(20000)/Carbomer_(940) nanocrystals. The optimal mass fraction of NaOH was determined as 0.8% by the drug release rate, redispersability, SEM morphology, encapsulation rate, and drug loading. The inclusion status of daidzein nanocrystals was determined by Fourier transform infrared spectroscopy(FTIR), thermogravimetric analysis(TGA), and X-ray diffraction(XRD) analysis to verify the feasibility of the preparation. The prepared nanocrystals showed the average Zeta potential of(-30.77±0.15)mV and(-37.47±0.64)mV and the particle sizes of(333.60±3.81)nm and(544.60±7.66)nm before and after daidzein loading, respectively. The irregular distribution of nanocrystals before and after daidzein loading was observed under SEM. The redispersability experiment showed high dispersion efficiency of the nanocrystals. The in vitro dissolution rate of nanocrystals in intestinal fluid was significantly faster than that of daidzein, and followed the first-order drug release kinetic model. XRD, FTIR, and TGA were employed to determine the polycrystalline properties, drug loading, and thermal stability of the nanocrystals before and after drug loading. The nanocrystals loaded with daidzein demonstrated obvious antibacterial effect. The nanocrystals had more significant inhibitory effects on Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa than daidzein because of the improved solubility of daidzein. The prepared nanocrystals can significantly increase the dissolution rate and oral bioavailability of the insoluble drug daidzein.
Sujets)
Hydroxyde de sodium , Résines acryliques , Escherichia coli , NanoparticulesRésumé
ObjectiveTo investigate the effect of microemulsion on the distribution of index components in different phases of Zexietang extract based on high performance liquid chromatography(HPLC) and phase separation process. MethodParticle size meter and transmission electron microscope were used to characterize the colloidal particles in blank microemulsion, aqueous extract of Zexietang and microemulsion extract of Zexietang. The phase separation process was established by high-speed centrifugation and dialysis, and based on this process, the aqueous extract and microemulsion extract of Zexietang were separated into the true solution phase, the colloidal phase and the precipitation phase, respectively. The contents of six components, including atractylenolide Ⅲ, atractylenolide Ⅱ, 23-acetyl alisol C, alisol A, alisol B and alisol B 23-acetate, were determined by HPLC with the mobile phase of water(A)-acetonitrile(B) for gradient elution(0-5 min, 40%-43%B; 5-20 min, 43%-45%B; 20-45 min. 45%-60%B; 45-75 min, 60%-80%B). The solubility of the index components in water and microemulsion was determined by saturation solubility method. ResultThe colloidal particles in the aqueous extract, microemulsion extract and blank microemulsion were all spherical, and the particle size, polydispersity index(PDI) and Zeta potential of the colloidal particles were in the order of aqueous extract >microemulsion extract >blank microemulsion. The results of phase separation showed that the colloidal phase and the true solution phase could be completely separated by dialysis for 2.5 h, and the phase separation process was tested to be stable and feasible. Compared with the aqueous extract of Zexietang, the use of microemulsion as an extraction solvent could increase the contents of atractylenolide Ⅲ, 23-acetyl alisol C, atractylenolide Ⅱ , alisol A, alisol B and alisol B 23-acetate by 3.75, 6.82, 35.47, 10.66, 35.41, 27.75-fold, and could increase the extraction efficiencies of the latter five constituents by 2.03, 1.15, 1.70, 6.43, 5.53 times. The solubility test showed that the microemulsion could significantly improve the solubility of atractylenolide Ⅱ, alisol A, alisol B and alisol B 23-acetate, but it had less effect on the solubility of atractylenolide Ⅲ and 23-acetyl alisol C. ConclusionMicroemulsion can improve the extraction efficiency and increase the distribution of the index components in the colloidal phase state of Zexietang to different degrees, providing a reference for the feasibility of microemulsion as an extraction solvent for traditional Chinese medicine.
Résumé
Abstract Candidiasis is one of the most common fungal infections of oral cavity in humans, causing great oral discomfort, pain and aversion to food. To develop more effective antifungal systems for the treatment of oral candidiasis, an oral mucoadhesive wafer containing sertaconazole solid dispersion (STZ-SD) was developed in this study. Dispersion of STZ in Soluplus® as a solubility enhancement excipient was done by melting, solvent evaporation and freeze drying method at various STZ to Soluplus® ratios. The optimized STZ-SD was then incorporated in the sodium carboxymethyl cellulose (SCMC) gel, xanthan gum gel, or their combination to prepare the lyophilized wafers. The swelling capacity, porosity, and mechanical, release and mucoadhesive properties of the wafers, together with their antifungal activity, were then evaluated. The melting method sample with the ratio of 8:1 showed the best results in terms of saturation solubility and dissolution rate. The STZ-SD-composite wafer exhibited higher hardness and mucoadhesion, as compared to those made of the SCMC polymer. The STZ-SD-wafer also exhibited a greater antifungal effect when compared to the STZ-wafer. The present study, thus, suggested that the STZ-SD-wafer could serve as a novel effective delivery system for oral candidiasis treatment.