PVP solid dispersions containing Poloxamer 407 or TPGS for the improvement of ursolic acid release

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.

Engineering the 182 site of cyclodextrin glucosyltransferase for glycosylated genistein synthesis / 生物工程学报

Genistein and its monoglucoside derivatives play important roles in food and pharmaceuticals fields, whereas their applications are limited by the low water solubility. Glycosylation is regarded as one of the effective approaches to improve water solubility. In this paper, the glycosylation of sophoricoside (genistein monoglucoside) was investigated using a cyclodextrin glucosyltransferase from Penibacillus macerans (PmCGTase). Saturation mutagenesis of D182 from PmCGTase was carried out. Compared with the wild-type (WT), the variant D182C showed a 13.42% higher conversion ratio. Moreover, the main products sophoricoside monoglucoside, sophoricoside diglucoside, and sophoricoside triglucoside of the variant D182C increased by 39.35%, 56.05% and 64.81% compared with that of the WT, respectively. Enzymatic characterization showed that the enzyme activities (cyclization, hydrolysis, disproportionation) of the variant D182C were higher than that of the WT, and the optimal pH and temperature of the variant D182C were 6 and 40℃, respectively. Kinetics analysis showed the variant D182C has a lower Km value and a higher kcat/Km value than that of the WT, indicating the variant D182C has enhanced affinity to substrate. Structure modeling and docking analysis demonstrated that the improved glycosylation efficiency of the variant D182C may be attributed to the increased interactions between residues and substrate.

Evaluation of physicochemical properties and dissolution studies on quality control of low water solubility drugs (raw materials and pharmaceutical formulations) / Evaluación de propiedades fisicoquímicas y estudios de disolución sobre el control de calidad de fármacos de baja solubilidad en agua (materias primas y formulaciones farmacéuticas)

SUMMARY The purpose of this study was to evaluate physicochemical properties and dissolution studies of furosemide (FUR), hydrochlorothiazide (HCTZ) and nifedipine (NIF), low water solubility drugs, in raw materials and pharmaceutical formulations. Surface and physicochemical characterization techniques -scanning electronic microscopy (SEM), thermogravimetry (TG), X-ray diffraction (XRD) and infrared (IR) spectrometry- as well as physical and physicochemical tests on tablets and capsules were applied as supporting information on drug quality control. Simple, rapid, and efficient UV-Vis methods were developed and validated for the determination of FUR, HCTZ and NIF samples. SEM exhibited considerable differences in the crystal morphological structures. Among the drugs studied, except for furosemide, more than one polymorph was present in the samples. Drug release profiles were satisfactory for all products. FUR and HCTZ tablets exhibited similar dissolution profiles, with very rapid release to the pharmaceutical specialties (reference, similar and generic). For HCTZ tablets, the similar drug (f2= 48.74) is not equivalent to the reference drug. NIF capsules (reference and compounded) showed a release >80% of stated on product labels, in 10 minutes. The results obtained in this study suggest that the quality parameters and drug dissolution profiles may have been influenced by the morphology and size of the crystals, excipients, and technological processes.

RESUMEN El propósito de este estudio fue evaluar las propiedades fisicoquímicas y los estudios de disolución de furosemida (FUR), hidroclorotiazida (HCTZ) y nifedipina (NIF), medicamentos de baja solubilidad en agua, en materias primas y formulaciones farmacéuticas. Técnicas de caracterización fisicoquímica y de superficie: microscopía electrónica de barrido (SEM), termogravimetría (TG), difracción de rayos X (XRD) y espectrometría infrarroja (IR), así como pruebas físicas y fisicoquímicas en tabletas y cápsulas que se aplicaron como información de apoyo sobre el control de calidad. Se desarrollaron y validaron métodos simples, rápidos y eficientes de UV-Vis para la determinación de muestras de FUR, HCTZ y NIF. SEM exhibió diferencias considerables en las estructuras morfológicas de cristal. Entre las drogas estudiadas, a excepción de la furosemida, más de un polimorfo estaba presente en las muestras. Los perfiles de liberación de fármacos fueron satisfactorios para todos los productos. Las tabletas FUR y HCTZ exhibieron perfiles de disolución similares, con una liberación muy rápida a las especialidades farmacéuticas (referencia, similares y genéricas). Para las tabletas de HCTZ, el medicamento similar (f2= 48,74) no es equivalente al medicamento de referencia. Las cápsulas NIF (de referencia y compuestas) mostraron una liberación >80% de la indicada en las etiquetas del producto, en 10 minutos. Los resultados obtenidos en este estudio sugieren que los parámetros de calidad y los perfiles de disolución del fármaco pueden haber sido influenciados por la morfología y el tamaño de los cristales, excipientes y procesos tecnológicos.

Effect of Maltodextrin Concentration and Inlet Air Temperature on Properties of Spray Dried Powder from Reverse Osmosis Concentrated Sweet Orange Juice

Abstract Sweet orange juice is an important part of diet since it is nutritious beverage offering good taste and play significant part in a healthy diet. High hygroscopicity, thermo-plasticity and presence of low molecular weight components in sweet orange juice offer low glass transition temperature (Tg), likely to form soft particle with sticky surface leading to sticky powder during drying. Maltodextrins are amorphous drying aids that tend to inhibit sugar crystallization and form a high Tg product after drying. In this study, the effect of the different spray drying parameters on the quality of powder derived from control and concentrated juice at three inlet air temperatures 120, 130 and 140 °C and at three levels of juice total soluble solids (TSS): maltodextrin levels at 1:0.5; 1:1 and 1:1.5 were studied. The impact of inlet air temperature and maltodextrin concentration has significantly affected various properties of sweet orange powder. For control juice, process yields increased with increase in inlet air temperature and maltodextrin concentration. However, for reverse osmosis (RO) concentrate, process yield increased with increase in maltodextrin concentration and decreased with increase in inlet air temperature. For control juice, process yields obtained were in the range of 12.59-41.16% and in case of concentrated juice, the process yield obtained was in the range of 21.35-56.95% at different combinations of inlet air temperature and maltodextrin concentrations. Spray-dried powder was considered as "possible" and "fair" in terms of flowability and cohesiveness. Vitamin C retention was high at lower inlet air temperature with lower concentration of maltodextrin.

Modeling of particle size and energetic requirement in amaranth grain ball-milling / Modelado del requerimiento energético y del tamaño de partícula en la molienda de bolas del grano de amaranto

ABSTRACT Amaranth flour is of high nutritional value, which makes it a potential food. Grinding of the grains is a necessary operation to obtain products with physical properties that provide the food products with adequate characteristics. To analyze the effect of grinding velocity and time on the particle diameters and physical properties of Amaranth flour by ball mill, a Doehlert design with triplicate at the central point was used. The tests were carried out with the mass ratio (balls/samples) (R1:5). Granulometry curve of each design system was fitted to the Rosin-Ramler-Bennet and Holmes-Hukki equations. A found a very significant effect of the velocity on the particle diameters (D50, D63 and D80). The flour obtained were modeled satisfactorily (r2>0.99) by using the Rosin-Ramler-Bennet equation, where the homogeneity index of (n1) was obtained, which was directly influenced by the milling energy. By using the Holmes-Hukki model, were able to model the characteristic diameters with the grinding energy; a critical region was observed between 100μm and 200μm, where lost efficiency in the size reduction. The excess energy, released in the critical region, caused the decrease in starch crystallinity and structural changes in the protein, which affect the functional properties of the flour. The planetary mill is emerging as an effective mean of modifying the functional properties in the development of new food products.

RESUMEN La harina de amaranto es de alto valor nutricional, convirtiéndola en un alimento potencial. La molienda de los granos es una operación necesaria, para brindarle a los productos alimenticios unas adecuadas propiedades físicas. Para analizar el efecto de la velocidad y el tiempo de molienda sobre el diámetro de particular y las propiedades físicas de la harina obtenida por molienda de bolas, se usó un diseño experimental Doehlert, con réplica en el punto central. En las pruebas de molinería se tuvo en cuenta la relación masa de bolas/masa de muestra (R1:5). Las curvas de granulometría de cada punto del diseño experimental fueron modeladas por las ecuaciones de Rosin-Ramler-Bennet y Holmes-Hukki. Se encontró un efecto muy significativo de la velocidad de molienda sobre los diámetros característicos (D50, D63 y D80). El modelo de Rosin-Ramler-Bennet ajustó satisfactoriamente (r2>0.99), además, se obtuvo el índice de homogeneidad (n1), el cual, fue afectado directamente por la energía de molienda. El uso del modelo de Holmes-Hukki permitió relacionar el diámetro de partícula con la energía de molienda y se logró observar una región crítica entre 100μm y 200μm, donde hay una reducción en la eficiencia de la reducción de tamaño de partícula. El exceso de energía liberada en la región crítica causó el descenso en la cristalinidad del almidón y provocó cambios en la estructura de las proteínas, lo cual, modificó las propiedades físicas de la harina. El Molino planetario es una técnica emergente y efectiva para modificar las propiedades funcionales en el desarrollo de nuevo productos alimenticios.

Physical characteristics of ceramic/glass-polymer based CAD/CAM materials: Effect of finishing and polishing techniques

PURPOSE: The aim of this study was to compare the effect of different finishing and polishing techniques on water absorption, water solubility, and microhardness of ceramic or glass-polymer based computer-aided design and computer-aided manufacturing (CAD/CAM) materials following thermocycling. MATERIALS AND METHODS: 150 disc-shaped specimens were prepared from three different hybrid materials and divided into five subgroups according to the applied surface polishing techniques. All specimens were subjected up to #4000 grit SiC paper grinding. No additional polishing has been done to the control group (Group I). Other polishing procedures were as follows: Group II: two-stage diamond impregnated polishing discs; Group III: yellow colored rubber based silicone discs; Group IV: diamond polishing paste; and Group V: Aluminum oxide polishing discs. Subsequently, 5000-cycles of thermocycling were applied. The analyses were conducted after 24 hours, 7 days, and 30 days of water immersion. Water absorption and water solubility results were analyzed by two-way ANOVA and Tukey post-hoc tests. Besides, microhardness data were compared by Kruskal-Wallis and Mann-Whitney U tests (P.05). CONCLUSION: Surface finishing and polishing procedures might negatively affect physical properties of hybrid ceramic materials. Nevertheless, immersion periods do not affect the microhardness of the materials. Final polishing by using diamond polishing paste can be recommended for all CAD/CAM materials.

Influence of 10-MDP concentration on the adhesion and physical properties of self-adhesive resin cements

OBJECTIVES: Self-adhesive resin cements contain functional monomers that enable them to adhere to the tooth structure without a separate adhesive or etchant. One of the most stable functional monomers used for chemical bonding to calcium in hydroxyapatite is 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP). The aim of this study was to evaluate the influence of the10-MDP concentration on the bond strength and physical properties of self-adhesive resin cements. MATERIALS AND METHODS: We used experimental resin cements containing 3 different concentrations of 10-MDP: 3.3 wt% (RC1), 6.6 wt% (RC2), or 9.9 wt% (RC3). The micro-tensile bond strength of each resin cement to dentin and a hybrid resin block (Estenia C&B, Kuraray Noritake Dental) was measured, and the fractured surface morphology was analyzed. Further, the flexural strength of the resin cements was measured using the three-point bending test. The water sorption and solubility of the cements following 30 days of immersion in water were measured. RESULTS: The bond strength of RC2 was significantly higher than that of RC1. There was no significant difference between the bond strength of RC2 and that of RC3. The water sorption of RC3 was higher than that of any other cement. There were no significant differences in the three-point bending strength or water solubility among all three types of cements. CONCLUSIONS: Within the limitations of this study, it is suggested that 6.6 wt% 10-MDP showed superior properties than 3.3 wt% or 9.9 wt% 10-MDP in self-adhesive resin cement.

Preparation, characterization and water solubility evaluation of porous starch loaded artemisinin microspheres / 中草药

Objective The fat-soluble artemisinin (Art), which is poorly soluble in water, was loaded with porous starch to form Art microspheres, and its physical and chemical properties were better than the original powder, so as to improve the water solubility of Art. Methods The porous starch particles were loaded on Art powder by physical adsorption method. The physical and chemical properties of Art microspheres loaded with porous starch were characterized and analyzed by SEM, BET, FTIR, XRD, DSC, and TG respectively. The saturated solubilities of porous starch loaded Art microspheres in water, artificial gastric juice and artificial intestinal fluid were determined. Results In the characterization test, we found that under the optimal preparation conditions, porous starch had successfully loaded Art to form microspheres with drug loading of (20.37 ± 0.61)% and entrapment efficiency of (81.86 ± 3.06)%. In the process of loading Art with porous starch, only physical changes happened. The original Art powder had been completely loaded by porous starch, showing that it had the same amorphous structure as porous starch, thus improving the water solubility of the original Art powder. The saturated solubility of the porous starch loaded Art microspheres was significantly improved, and the water, artificial gastric juice and artificial intestinal fluid were 3.77, 1.64, and 1.72 times higher than the original Art powder, respectively. Conclusion This paper significantly improved the water solubility of Art powder and provided important research basis for solving the clinical application of insoluble drugs.

Synthesis and biological evaluation of aminoalcohol rheinate as anti-osteosarcoma agents / 药学学报

Rhein (4,5-dihydroxyanthraquinone-2-carboxylic acid) is the primary anthraquinone in the roots of rhubarb. A recent study showed that rhein can inhibit tumor cell proliferation and induce apoptosis in human tumor cells. However, the clinical application of rhein has been hampered by its poor bioavailability, low aqueous solubility and gastrointestinal disorders. In current study, twenty-four target compounds were designed and synthesized by coupling various hydrophilic alkanolamines to the 2-carboxyl of rhein, and their structures were established by IR, HR-MS, 1H NMR spectra. Solubility test showed that all compounds were 10.04 to 15.08 mg·mL-1 in water, which was 220 to 330-fold better than that of rhein (0.045 6 mg·mL-1). All of rhein derivatives displayed more potent anti-tumor activity than rhein, and most of them were comparable to adriamycin, particularly, compound 4t exhibited IC50 value of 2.08 μmol·L-1, more effective than adriamycin (IC50=2.35 μmol·L-1). Hydroxyapatite adsorption experiment suggests that compound 4t has a better bone affinity than that of tetracycline.

Synthesis of A New Type of Responsive Hydrophilic Block Copolymer Fluorescence Probe and Its Application in Detection of Aluminum Ion in Agricultural Products / 分析化学

A temperature-responsive hydrophilic block copolymer fluorescence sensor based on selective analysis of Al3+was designed and synthesized. The polymer fluorescent probe (L64-BTPA-SHMA) was synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization and characterized by 1 H NMR,and the recognition performance of the polymer probe was studied by fluorescence spectroscopy. It was found that the fluorescence response of Al3+detected by this polymer fluorescence probe was significantly affected by temperature. The higher the temperature, the lower the fluorescence intensity was observed. The results showed that 0.1 g/L polymer fluorescent probe had a good selectivity to Al3+in buffer solution at 25℃and pH 7.4,and was not affected by other metal ions. A fluorescence detection method based on this polymer probe for Al3+was developed. In this method,the fluorescence intensity was linear with Al3+concentration in the range of 2. 0 -18. 0 μmol/L, with a correlation coefficient of 0. 9977 and a detection limit of 1.43 μmol/L. The fluorescence response between the polymer fluorescence chemosensor and Al3+could be altered by controlling the temperature change. The successful application of the polymer fluorescence probe for detecting Al3+residues in agricultural products has practical application value.

Comparison of water absorption, solubility and monomer release of six kinds of light-curing composite resins / 吉林大学学报(医学版)

Objective:To compare the water absorption values,solubility values and monomer release amounts of six kinds of light curing composite resins and explore the influencing factors,and to elucidate their relationships with the material compositions and the immersing solvent.Methods:The water absorption and solubility values of six kinds of composite resins,including FiltekTM Z250 (Z250),FiltekTM Z350 XT (Z350),Aelite LS Posterior (ALS),CLEARFIL MAJESTY Posterior (CMP),Neofil Nano (NN),and Tetric N-Ceram (TNC),were measured according to ISO 4049-2009.The concentrations of eluted Bis-GMA and TEGDMA were tested by liquid chromatography/mass spectrometry after the specimens were immersed in 75％ ethanol solution for different time (24 h,7 d,1 month,and 3 months).Results:The water absorption values of six kinds of composite resins were in ascending order of ALS ＜CMP ＜TNC ≈Z250 ＜NN ＜Z350,there were significant differences between groups (P＜0.05);the solubility values were Z350 ＜NN≈ALS≈CMP≈Z250 ＜TNC,there were significant differences between groups (P＜0.05).The release amounts of Bis-GMA were increased slowly with the prolongation of time (P＜0.05),while the values of ALS and CMP at 3 months were decreased (P＜0.05);the descending order ofBis-GMA release amounts at 3 months was NN＞ TNC＞ Z250＞ Z350＞ ALS＞ CMP (P＜0.05).The released TEGDMA was not found in NN and TNC.The release amounts of TEGDMA of the other four resins were increased slowly with the prolongation of time (P＜0.05),and the release amount of CMP at 3 months was decreased (P＜0.05);the order of amount at 3 months was ALS＞ CMP＞ Z250＞ Z350 (P＜0.05).Conclusion:The water absorption values,solubility values and monomer release amounts of different composite resins are different,and they are related to their organic matrix compositions and the immersing solvent.

Comparison of water absorption, solubility and monomer release of six kinds of light-curing composite resins / 吉林大学学报(医学版)

Objective: To compare the water absorption values, solubility values and monomer release amounts of six kinds of light curing composite resins and explore the influencing factors, and to elucidate their relationships with the material compositions and the immersing solvent. Methods: The water absorption and solubility values of six kinds of composite resins, including FiltekTM Z250(Z250), FiltekTM Z350 XT (Z350), Aelite LS Posterior (ALS), CLEARFIL MAJESTY Posterior (CMP), Neofil Nano (NN), and Tetnc N-Ceram (TNC), were measured according to ISO 4049-2009. The concentrations of eluted Bis-GMA and TEGDMA were tested by liquid chromatography/mass spectrometry after the specimens were immersed in 75% ethanol solution for different time (24 h, 7 d, 1 month, and 3 months). Results: The water absorption values of six kinds of composite resins were in ascending order of ALS TNC> Z250> Z350> ALS> CMP (P CMP> Z250> Z350 (P<0. 05). Conclusion: The water absorption values, solubility values and monomer release amounts of different composite resins are different, and they are related to their organic matrix compositions and the immersing solvent.

Effects of surfactants on water solubility and anti-hepatic fibrosis of curcuminoids / 中草药

Objective To increase the water solubility of curcumin constituents by three kinds of food grade surfactants, and to study the effect of surfactants on the quality standard and stability and anti-hepatic fibrosis in vivo of curcumin solution. Methods The high-speed dispersion method was used to prepare the solution of curcuminoids-surfactants. The qualitative analysis of curcuminoids was confirmed by LC-MS/MS. HPLC-DAD fingerprinting was established and quantitative analysis was conducted. And the effects on anti-liver fibrosis of different concentrations curcumin ratio solution were evaluated by rat model. Results The maximum water solubility of curcumin constituents was 1.387 mg/mL. LC-MS/MS analysis showed that the structure of curcuminoids were stable; The results of fingerprinting analysis demonstrated that the similarity of 18 batches of samples were higher than 99%. The contents of curcumin, demethoxycurcumin and bisdemethoxycurcumin in different batches of samples were stable with the RSD of 1.60%, 2.24%, and 3.74%. The rat model of hepatic fibrosis showed that the contents of AST and ALT in free curcumin suspension group were (64.1 ± 20.3) and (45.1 ± 13.9) U/L, respectively, while that solution of curcuminoids-surfactants group was (19.4 ± 8.7) and (11.8 ± 4.9) U/L. Conclusion The solubility of curcuminoids was increased 517 times compared with the free state (2.677 μg/mL) after solubilization with surfactants, and repeated tests indicated that the structure and contents of curcuminoids were stable; the solubilized curcuminoids exhibited better anti-liver fibrosis effects than the free.

Synthesis and Biological Application of A Water-Soluble Fluorescent Probe Based on Coumarin Derivatives for Detection of Ferric Ion / 分析化学

A water-soluble fluorescent probe (7-diethyl amino-3-formaldehyde coumarin) for Fe3+ detection was designed and synthesiZed, and its structure was confirmed by 1 HNMR, 13 CNMR and MS spectra.This probe showed high emission intensity at 471 nm.With the continuous addition of Fe3+, the emission intensities at 471 nm decreased gradually, and showed an excellent linearity with Fe3+in the range of 0.02-60 μmol/L, and the regression equation was I=322.56-4.86CFe3+.This probe was able to detect Fe3+ qualitatively and quantitatively with the detection limit as low as 22 nmol/L.Besides, this probe showed high sensitivity to Fe3+over other metal ions.The detection process was reversible, which could be recycled for the Fe3+detection.In terms of good optical properties and the strong fluorescence in physiological pH, the probe was successfully applied in imaging Fe3+ of living Ramos cells.

Preparation, Characterization and Water Solubility of Inclusion Complexes of Daidzein with Amino-modified β-Cyclodextrins / 分析化学

To improve the water solubility of daidzein, solid inclusion complexes of daidzein with two amino-modified β-cyclodextrins (ACDs), i.e., mono-6-amino-6-deoxy-β-cyclodextrin (NCD) and mono-6-ethylenediamino-6-deoxy-β-cyclodextrin (ENCD), were prepared by the saturated solution method in water under the preparation conditions as follows: the ratio of daidzein/ACD was 3∶1 and the stirring time was 72 h (83% and 67% yields, respectively).The formation of two inclusion complexes was confirmed by x-ray diffractometry (XRD) and themogravimetric (TG) analysis.The inclusion stoichiometry of the inclusion complexes was 1∶1 from the Job plot and their complexation stability constants (KS) were 899.2 and 203.8 L/mol from fluorescence titration, respectively.After formation of inclusion complexes with NCD and ENCD, the water solubility of daidzein was dramatically raised from 8.31 μg/mL to 15.2 and 13.2 mg/mL at 25℃, increasing by 1800-fold and 1500-fold.

Synthesize of water-solubility derivant of 6,7,4′-trihydroxyisoflavone (T2)and study of its inhibition effect on human breast cancer cell proliferation / 重庆医学

Objective To synthesize of water-solubility derivant of 6,7,4′- trihydroxyisoflavone(T2 ),to characterize its structure and to evaluate its anti-tumor activity.Methods The sulfonic group(-SO3 H)was grafted to 3'position in loop B of T2 through sulfonation reaction,then strong aqua was added to above production,and obtained a water-solubility elevated compound named T2-SO3 (NH4 )2 through ammoniation.The construction of T2-SO3 (NH4 )2 was characterized by 1 H-NMR,13 C NMR,MS and element analysis.Its activity for killing human breast cancer cells (Hela)was analyzed by CCK-8 assay and flow cytometry.Re-sults The two kinds of water-solubility derivant of T2-SO3 H·2H2 O and T2-SO3 (NH4 )2 were obtained through above methods, and their yield rates were 96% and 75% respectively.The biological experiments showed that the anti-tumor activity of T2-SO3 (NH4 )2 was significantly enhanced.Conclusion Compared to T2,T2-SO3 (NH4 )2 exhibit higher biocompatibility and anti-tumor activity with vast biological application prospect.

Enzymatic biosynthesis of novel neobavaisoflavone glucosides via Bacillus UDP-glycosyltransferase / 中国天然药物

The present study was designed to perform structural modifications of of neobavaisoflavone (NBIF), using an in vitro enzymatic glycosylation reaction, in order to improve its water-solubility. Two novel glucosides of NBIF were obtained from an enzymatic glycosylation by UDP-glycosyltransferase. The glycosylated products were elucidated by LC-MS, HR-ESI-MS, and NMR analysis. The HPLC peaks were integrated and the concentrations in sample solutions were calculated. The MTT assay was used to detect the cytotoxic activity of compounds in cancer cell lines. Based on the spectroscopic analyses, the two novel glucosides were identified as neobavaisoflavone-4'-O-β-D-glucopyranoside (1) and neobavaisoflavone-4', 7-di-O-β-D-glucopyranoside (2). Additionally, the water-solubilities of compounds 1 and 2 were approximately 175.1- and 4 031.9-fold higher than that of the substrate, respectively. Among the test compounds, only NBIF exhibited weak cytotoxicity against four human cancer cell lines, with IC values ranging from 63.47 to 72.81 µmol·L. These results suggest that in vitro enzymatic glycosylation is a powerful approach to structural modification, improving water-solubility.

Discoloration of various CAD/CAM blocks after immersion in coffee

OBJECTIVES: This study evaluated color differences (ΔEs) and translucency parameter changes (ΔTPs) of various computer-aided design/computer-aided manufacturing (CAD/CAM) blocks after immersion in coffee. MATERIALS AND METHODS: Eight CAD/CAM blocks and four restorative composite resins were evaluated. The CIE L*a*b* values of 2.0 mm thick disk-shaped specimens were measured using the spectrophotometer on white and black backgrounds (n = 6). The ΔEs and ΔTPs of one day, one week, and one month immersion in coffee or water were calculated. The values of each material were analyzed by two-way ANOVA and Tukey's multiple comparisons (α = 0.05). The ΔEs after prophylaxis paste polishing of 1 month coffee immersion specimens, water sorption and solubility were also evaluated. RESULTS: After one month in coffee, ΔEs of CAD/CAM composite resin blocks and restorative composites ranged from 1.6 to 3.7 and from 2.1 to 7.9, respectively, and ΔTPs decreased. The ANOVA of ΔEs and ΔTPs revealed significant differences in two main factors, immersion periods and media, and their interaction except for ΔEs of TEL (Telio CAD, Ivoclar Vivadent). The ΔEs significantly decreased after prophylaxis polishing except GRA (Gradia Block, GC). There was no significant correlation between ΔEs and water sorption or solubility in water. CONCLUSIONS: The ΔEs of CAD/CAM blocks after immersion in coffee varied among products and were comparable to those of restorative composite resins. The discoloration of CAD/CAM composite resin blocks could be effectively removed with prophylaxis paste polishing, while that of some restorative composites could not be removed.

Enhancement of Simvastatin dissolution by surface solid dispersion:effect of carriers and wetting agents.

The aim of this work was to improve the aqueous solubility of simvastatin using the surface solid dispersion (SSD) technique. Water soluble (mannitol and lactose) and insoluble (Avecil PH101) carriers were used. The effect of the addition of polymeric wetting agents (namely PEG6000, Pluronic F68, Myrj 52 and PVP K-30) to drug/carrier composite was also investigated. SSD was prepared by solvent evaporation technique. All formulations were studied regarding the dissolution behavior and solid state characterization (DSC, FT-IR and Xray diffraction). Both water soluble and insoluble carriers improved dissolution behaviour compared to unprocessed drug, with the former showing the best results. Addition of wetting agent to the water insoluble carrier greatly improved drug dissolution, with PVP K-30 showing better dissolution parameters that was comparable to that of marketed product. Physical state characterization using DSC indicated the marked reduction in drug crystallinity. Xray diffraction confirmed drug amorphousness. The results indicated that SSD may serve as a successful strategy for enhancing solubility of poorly water soluble drugs by proper manipulation of the used additives

Formulation and evaluation of dexamethasone loaded stearic acid nanoparticles by hot homogenization method.

Dexamethasone is a type of steroid medication having anti-inflammatory and immunosuppressant effects. One of the major problems with this drug is its low solubility in water which results into poor bioavailability after oral administration. So the objective of the present work is to improve the solubility and dissolution rate of dexamethasone using its solid lipid nano particles (SLNPs) with stearic acid as solid lipid, lutrol F-68 as surfactant and tween-80 as stabilizer. SLNPs are prepared by hot homogenization method at different ratio of drug, lipid, surfactant and stabilizer and designated as DNP1 to DNP6. In vitro dissolution study was performed using the USP type II apparatus (paddle method) at 50 rpm to a temperature of 37°±0.5°C in distilled water containing 0.75% w/v SLS (sodium lauryl sulfate). The absorbance of sample was measured spectrophotometrically at λmax 239nm on a UV-Visible spectrophotometer. Release pattern of drug was found to follow zero order, first order and Korsmeyer-Peppas equations. Improvement of dissolution was observed in all the solid lipid nano particles as compared to pure drug. Pure drug showed only 27.25% release in 50 min whereas the dexamethasone SLNPs showed faster (66.19%) in vitro drug release. Hence, this finding indicates that dexamethasone SLNPs prepared by hot homogenization method can be used to enhance the dissolution rate and to show novel application to this drug delivery system.