The technique of liquisolid compress is a new technique developed in 1990s, which was considered to be the most promising technique to improve the dissolution of water-insoluble drugs. In this article, tanshinone II(A) and the extracts of the ester-solubility fractions were chosen as the model drugs to evaluate the effects of the liquisolid technique for enhancement of dissolution properties of tanshinone II(A). Several liquisolid tablets (LS) formulations containing different dosage of drugs and various liquid vehicle were pre-pared and for all the formulations, microcrystalline cellulose and silica were chosen as the carrier and coating materials to evaluate their flow properties, such as angle of repose, Carr's compressibility index and Hausner's ratio. The interaction between drug and excipients in prepared LS compacts were studied by differential scanning calorimetry(DSC) and X-ray powder diffraction (XRPD). The dissolution curves of tanshinone II(A) from liquisolid compacts were investigated to determine the technique's effect in improving the dissolution of tanshinone II(A) and its impacting factors. According to the results, the dissolution increased with the rise in the dissolution of the liquid-phase solvent. The R-value and drug dosage can significantly affect the drug release, but with less impact on active fractions. This indicated that liquisolid technique is a promising alternative for improvement of dissolution property of water-soluble drugs, and can make a synergistic effect with other ester-soluble constituents and bettern improve the release of tanshinone II(A). Therefore, the technique of liquisolid compress will have a better development prospect in traditional Chinese medicines.
Calorimetry, Differential Scanning ; Diterpenes, Abietane ; chemistry ; Solubility ; X-Ray Diffraction

STATEMENT OF PROBLEMS: The heat produced during polymerization of polymer-based provisional materials may cause thermal damage to the vital pulp. PURPOSE: This study was performed to evaluate the exotherm reaction of the polymerbased provisional materials during polymerization by differential scanning calorimetry and to compare the temperature changes of different types of resins. MATERIAL AND METHODS: Three dimethacrylate-based materials (Protemp 3 Garant, Luxatemp Plus, Luxatemp Fluorescence) and five monomethacrylate-based material (Snap, Alike, Unifast TRAD, Duralay, Jet) were selected. Temperature changes of polymer-based provisional materials during polymerization in this study were evaluated by D.S.C Q-1000 (TA Instrument, Wilmington, DE, USA). The following three measurements were determined from the temperature versus time plot: (1) peak temperature, (2) time to reach peak temperature, (3) heat capacity. The data were statistically analyzed using one-way ANOVA and multiple comparison Bonferroni test at the significance level of 0.05. RESULTS: The mean peak temperature was 39.5 degrees C (+/- 1.0). The peak temperature of the polymer-based provisional materials decreased in the following order: Duralay > Unifast TRAD, Alike > Jet > Luxatemp Plus, Protemp 3 Garant, Snap, Luxatemp Fluorescence. The mean time to reach peak temperature was 95.95 sec (+/- 64.0). The mean time to reach peak temperature of the polymer-based provisional materials decreased in the following order: Snap, Jet > Duralay > Alike > Unifast TRAD > Luxatemp Plus, Protemp 3 Garant, Luxatemp Fluorescence. The mean heat capacity was 287.2 J/g (+/- 107.68). The heat capacity of the polymer-based provisional materials decreased in the following order: Duralay > TRAD, Jet, Alike > Snap, Luxatemp Fluorescence, Protemp 3 Garant, Luxatemp Plus. CONCLUSION: The heat capacity of materials, determined by D.S.C., is a factor in determining the thermal insulating properties of restorative materials. The peak temperature of PMMA was significantly higher than others (PEMA, dimethacrylate). No significant differences were found among PEMA (Snap) and dimethacrylate (P > 0.05). The time to reach peak temperature was greatest with PEMA, followed by PMMA and dimethacrylate. The heat capacity of PMMA was significantly higher than others (PEMA, dimethacrylate). No significant differences were found among PEMA and dimethacrylate (P>0.05).
Calorimetry, Differential Scanning* ; Crowns* ; Denture, Partial, Fixed* ; Fluorescence ; Hot Temperature ; Polymerization ; Polymers ; Polymethyl Methacrylate

OBJECTIVETo enhance the dissolution rate of daidzein with solid dispersion technique.

METHODSolid dispersions were prepared by the solvent method using water-solubility chitosan as a hydrophilic carrier. DSC, IR and X-ray methods were used to verify the formation of solid dispersion.

RESULTDissolution percentages of solid dispersions were more than 90 percent in the drug-carrier ratio of 1:5 and 1:9. But dissolution percentages of physical mixtures and pure drug were 40 and 38.4 percent respectively. Part of daidzein dispersed in solid dispersion in the form of microcrystalline.

CONCLUSIONWater-soluble chitosan solid dispersion can significantly increase dissolution rate of daidzein.

Calorimetry, Differential Scanning ; Chitosan ; chemistry ; Isoflavones ; chemistry ; Solubility ; Spectrophotometry, Infrared ; Water ; chemistry ; X-Ray Diffraction

OBJECTIVETo prepare the solid dispersion of tanshinone II A (TS II A) by the combined application of nano-silica and poloxamer 188 (F68), in order to observe its dissolution and stability.

METHODTanshinone II A solid dispersion was prepared by the solvent method with nano-silica and poloxamer 188 as binary vectors. Its physical characteristics, in vitro dissolution and stability were further assessed.

RESULTThe tanshinone II solid dispersion was prepared with the weight ratio of nano-silica and poloxamer 188 of 1: 3. The differential scanning calorimetry (DSC) demonstrated that Tanshinone II A existed in vectors as amorphous state. The in vitro dissolution of tanshinone II A solid dispersion is up to 90% at 60 min. Accelerating experiment showed that content and in vitro dissolution of tanshinone II A solid dispersion did not change after storage over 3 months.

CONCLUSIONSolid dispersion of binary vector of tanshinone II A can obviously improve the dissolution and stability of tanshinone II in practice.

Calorimetry, Differential Scanning ; Diterpenes, Abietane ; chemistry ; Drug Stability ; Drugs, Chinese Herbal ; chemistry ; Solubility

Baicalin extremely fine powder was made by using ball-mill and the effect of micronization on the micromeritics properties of baicalin was studied and analyzed. The microstructures of baicalin ordinary and extremely fine powder were compared by scanning electron microscope, differential scanning calorimeter and X-ray diffraction and the powder characteristic of them was investigated. The hygroscopicity was studied. The effect of micronization on the dissolution of baicalin was investigated. The results showed that the chemical constituents of baicalin were not changed after micronization with better compressibility. It was confirmed that micronization technology had a certain application value in promoting the insoluble component of baicalin absorption with higher dissolution.
Calorimetry, Differential Scanning ; Drugs, Chinese Herbal ; chemistry ; Flavonoids ; chemistry ; Particle Size ; Solubility ; Wettability ; X-Ray Diffraction

5R-5-hydroxytriptolide (LLDT-8) is a new drug candidate which is in clinical trial treating rheumatoid arthritis. Polymorph screening of the compound was carried out in this study. Polymorph of LLDT-8 was prepared by evaporative crystallization and antisolvent crystallization methods and was characterized by powder X-ray diffraction (p-XRD), infrared spectrometry (IR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TG). It was found that p-XRD patterns, DSC curves, TG curves and IR spectra of the LLDT-8 samples prepared by the above recrystallization methods were all consistent. The 20 of main peaks in the p-XRD patterns appeared at 7.58 degrees, 8.14 degrees, 8.66 degrees, 15.46 degrees, 16.46 degrees, 29.54 degrees, 31.16 degrees and 38.26 degrees, while the infrared absorption peaks appeared at 3 471.3, 2 962.2, 2 887.0, 1 762.6, 1 677.8, 1 432.9, 1 365.4, 1 247.7, 1 080.0, 1 031.7 and 877.5 cm(-1). LLDT-8 was decomposed at 271.2 degrees C based on the determination from DSC and TG. It was showed in single crystal X-ray diffraction study that LLDT-8 crystal was monoclinic with the space group being P2 (1). The cell parameters were found to be: a = 11.460 1 (11), b = 6.320 5 (6), c = 13.028 1 (12), alpha = 90.00, beta = 115.557 (2) and gamma = 90.00. The crystal was a hydrogen-bonded dimmer. The slurry experiments, which were further conducted in solvents with different polarities, confirmed the stability of solid state of LLDT-8 based on the p-XRD determination. The polymorph of LLDT-8 made assurance of its efficacy consistence during its clinical trials.
Calorimetry, Differential Scanning ; Crystallization ; Diterpenes ; chemistry ; Drug Stability ; Spectrophotometry, Infrared ; Thermogravimetry ; X-Ray Diffraction

The paper is aimed to establish a methods for identication of pearl powder and conch powder from different origins. Hermetic aluminum pan was used to encapsulate samples. The optimal testing conditions were: heating rate 10 degrees C x min(-1), sample weight 3 mg and nitrogen gas flow rate 40 mL x min(-1). The enthalpy values of pearl powder and conch powder was obvious different. Identication of pearl powder and conch powder by DSC is a practical method for its accuracy, convenience and practificality.
Animal Shells ; chemistry ; Animals ; Calorimetry, Differential Scanning ; methods ; China ; Discriminant Analysis ; Pinctada ; chemistry ; classification ; Powders ; chemistry

Porous silica was used as a carrier to prepare tanshinone solid dispersions (SDs). sThe effect of the spray drying method or the solvent method on the drug dissolution of SD was studied. The structure characteristics of SDs was analyzed by SEM, DSC,XPRD and FTIR. And in vitro dissolution was also investigated. The results showed that drugs were highly dispersed into SDs prepared by spray drying method and the solvent method in amorphous form. In addition, the results of the dissolution tested in vitro exhibited that the tanshinone I and tanshinone II A, accumulated dissolutions of SDs prepared using solvent achieved 80. 9% ,84. 6% and 86. 2% ,88. 7% within 45,60 min, respectively. And SDs prepared using spray-drying method were 92.7% ,95. 3% and 95. 8%, 97. 1% within 45,60 min, respectively. The tanshinone SDs were prepared successfully by spray drying method and solvent method. The SDs prepared by spray drying method was more conducive to improving the dissolution.
Calorimetry, Differential Scanning ; Diterpenes, Abietane ; chemistry ; isolation & purification ; Porosity ; Silicon Dioxide ; chemistry ; Spectroscopy, Fourier Transform Infrared

OBJECTIVES: The purpose of the present study was to evaluate the effects of proanthocyanidin (PAC), a crosslinking agent, on the physical properties of a collagen hydrogel and the behavior of human periodontal ligament cells (hPDLCs) cultured in the scaffold. MATERIALS AND METHODS: Viability of hPDLCs treated with PAC was measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The physical properties of PAC treated collagen hydrogel scaffold were evaluated by the measurement of setting time, surface roughness, and differential scanning calorimetry (DSC). The behavior of the hPDLCs in the collagen scaffold was evaluated by cell morphology observation and cell numbers counting. RESULTS: The setting time of the collagen scaffold was shortened in the presence of PAC (p < 0.05). The surface roughness of the PAC-treated collagen was higher compared to the untreated control group (p < 0.05). The thermogram of the crosslinked collagen exhibited a higher endothermic peak compared to the uncrosslinked one. Cells in the PAC-treated collagen were observed to attach in closer proximity to one another with more cytoplasmic extensions compared to cells in the untreated control group. The number of cells cultured in the PAC-treated collagen scaffolds was significantly increased compared to the untreated control (p < 0.05). CONCLUSIONS: Our results showed that PAC enhanced the physical properties of the collagen scaffold. Furthermore, the proliferation of hPDLCs cultured in the collagen scaffold crosslinked with PAC was facilitated. Conclusively, the application of PAC to the collagen scaffold may be beneficial for engineering-based periodontal ligament regeneration in delayed replantation.
Calorimetry, Differential Scanning ; Cell Count ; Collagen* ; Cytoplasm ; Humans ; Hydrogel* ; Periodontal Ligament ; Regeneration ; Replantation

OBJECTIVETo optimize the preparation process of solid dispersions of ginkgolides to improve the drug dissolution.

METHODThe influence of formulation and preparation technology on drug release from solid dispersions was investigated by single factor test. The X-ray diffraction analysis (XRD) and differential scanning calorimetry (DSC) were used to characterize the solid dispersions of ginkgolides.

RESULTThe solubilization efficiency of solid dispersions using PVP k30 as carrier was better than that taking poloxamer 188 or HPMC as matrix. The results of XRD and DSC showed that ginkgolides existed in solid dispersion at amorphous form or solvates form. The dissolution rate of ginkgolide B in solid dispersion was increased dramatically compared with raw material.

CONCLUSIONSolid dispersions could significantly improve solubility and dissolution rate of ginkgolides.

Calorimetry, Differential Scanning ; Ginkgolides ; chemistry ; Pharmaceutical Preparations ; chemistry ; Solubility ; X-Ray Diffraction