[Effects of maltodextrin on water adsorption and thermodynamic properties of Codonopsis Radix spray-dried powder].

This study aims to reveal the effects of maltodextrin(MD) on the water adsorption and thermodynamic properties of Codonopsis Radix(DS) spray-dried powder by determining the moisture and energy changes of the powder in the process of moisture absorption. The static weighing method was used to obtain the isothermal water adsorption data of the spray-dried powder in 6 saturated salt solutions(KAc, MgCl_2·6H_2O, K_2CO_3, NaBr, NaCl, and KCl) at 3 temperatures(25, 35, and 45 ℃). Six models were used for fitting of the water adsorption process, and the most suitable model was selected based on the model performance. Furthermore, the corresponding net equivalent adsorption heat and differential entropy were calculated, and the adsorption entropy change was integrated. The linear relationship between net equivalent adsorption heat and differential entropy was drawn based on the entropy-enthalpy complementarity theory. The results showed that the water adsorption properties of DS and DS-MD spray-dried powder followed the type Ⅲ isotherm and was well fitted by the GAB model. The monolayer water content M_0 decreased with the increase in temperature. At the same temperature, the M_0 of DS spray-dried powder decreased after the addition of MD. The net equivalent adsorption heat and differential entropy of DS and DS-MD spray-dried powder decreased with the increase in water content, which presented a linear relationship. The addition of MD decreased the water activity corresponding to the lowest integral adsorption entropy of the powder, and the system became more stable. The results indicated that the spray-dried powder became more stable after the addition of MD.

[Water migration and kinetics of Arecae Semen during moistening process].

In this study, low-field nuclear magnetic resonance(LF-NMR) and magnetic resonance imaging(MRI) were employed to analyze the water distribution, status, and migration in the moistening process of Arecae Semen. Peleg model was adopted to study the water absorption kinetics of Arecae Semen moistened at different water temperatures(10, 30, and 50 ℃). The Arecae Semen samples soaked at different water temperatures all contained four water states: binding water T_(21), non-flowing water T_(22), free water T_(23), and unbound water T_(24). Non-flowing water had the largest increase in peak area during the moistening process, followed by free water. The peak areas of non-flowing water, free water, and total water were correlated with the water content(P<0.01). Therefore, LF-NMR can quickly and non-destructively predict the water content of Arecae Semen during moistening. The peak area of non-flowing water and the content of free water were correlated with the content of arecoline in the soaking solution(P<0.01), which indicated that the faster flow of non-flowing water and more free water corresponded to more arecoline dissolved. The MRI images showed that the water migration pathway varied at different soaking temperatures, and the moistening degree obtained by this means was consistent with that obtained based on traditional experience. The rate constant K_1 fitted by Peleg model decreased with the increase in water temperature, while the capacity constant K_2 showed an opposite trend. The Arrhenius equation fitting of K_1 with temperature showed that the activation energy of Arecae Semen in the moistening process was 32.98 kJ·mol~(-1). LF-NMR/MRI can be used to analyze the water status and content and determine the end moisturing point of Arecae Semen. Peleg model can accurately describe the water absorption properties of Arecae Semen in the moistening process. The findings of this study can guide the moistening optimization and mechanism research of other seed Chinese medicinal materials.

[Study on endpoint determination method of tablet coating based on 3σ criteria and logic regression].

This paper explores the statistical distribution characteristics of coating film thickness, so as to present a new method for determining coating endpoint based on 3σ criterion and logic regression. Firstly, the spectrum and thickness of 4 batch samples were collected. Secondly, the spectral range of normal products was obtained by 3σ criterion, with the spectral feature NI as the number of test spectrum in the above range. Then, the model based on 3σ criterion and logic regression was built according to the best condition in K-fold cross-validation and the determined threshold of qualified rate in the coating endpoint. Finally, the qualified rate of test set samples at different time points was calculated by the above model, and the above change trend and the threshold value were combined to determine the coating endpoint. The results of KS analysis showed the distribution of thickness of the qualified products followed the normal distribution(P=0.081>0.05). The accuracy of the coating endpoint determination was as high as 100% by the model based on 3σ criterion and logic regression when the determined threshold of qualified rate was 90%. Therefore, the 3σ criterion was feasible to the research of coating eligibility. This paper reveals certain random phenomena in the coating process, and the method features a high accuracy, quick analysis and a good interpretability, which provides a reference for online detection and qualify evaluation in future.

[Research on extraction process of Digeda-4 flavored decoction based on QbD concept].

To establish and validate the design space of the Digeda-4 flavored decoction( DGD-4D) extraction process by using the quality by design( Qb D) concept. With DGD-4D decoction pieces as a model drug,with the transfer rate of aesculin,picroside I,picroside Ⅱ,geniposide and the yield of extract as critical quality attributes( CQAs),the single factor experiment design was used to determine the level of each factor; the Plackett-Burman experiment design was used to select the critical process parameters( CPPs);and the Box-Behnken experiment design was used to optimize the extraction process. The design space of the DGD-4D extraction process was established,and finally,four experimental points were selected to verify the established model. The single factor experiment determined the levels of each factor,including soaking time 60 min and 30 min,water adding volume 12 times and 8 times,extraction time 90 min and 30 min,number of extraction times 3 times and 1 time,as well as extraction temperature 100 ℃ and 90 ℃.By Plackett-Burman experimental design,the DGD-4D water addition,extraction time and number of extraction times were determined to be CPPs. The Box-Behnken experimental variance analysis showed that P of the regression model was less than 0. 01 and the misstated value was more than 0. 01,indicating that the model had good predictive ability,and the operation space of CPPs in the DGD-4D extraction process was determined as follows: the amount of water addition was 10-12 times; extraction time 50-80 min; and number of extraction times was 3 times. The design space of DGD-4D extraction process based on the concept of Qb D is conducive to improving the stability of product quality and laying a foundation for the future development of DGD-4D.

[Fingerprinting and multi-indicator quantitative analysis of Mongolian drug Digeda-4 decoction].

To establish the high performance liquid chromatography (HPLC) fingerprint for Digeda-4 decoction (DGD-4D), determine the contents of aesculetin, geniposide, picroside Ⅰ, picroside Ⅱ and ellagicacid in DGD-4D, and provide the scientific foundation for quality control of DGD-4D. The analysis was performed on Diamonsil(2) C18 (4.6 mm×250 mm,5 µm) column, with methanol-0.1% phosphoric acid aqueous solution as mobile phase for gradient elution. The flow rate was 1.0 mL·min⁻¹; injection size was 10 µL; temperature was maintained at 30 °C, and the detection wavelength was set at 254 nm. The common mode of DGD-4D HPLC fingerprint was established, and the hidden information was analyzed by Chemometrics. Chromatographic peaks for DGD-4D were identified by HPLC and quantitative analysis was conducted for characteristic peaks. There were 17 common peaks in the fingerprints and the similarity of the fingerprints was over 0.9 in all 15 batches. The samples were broadly divided into four kinds by principal component analysis and clustering analysis. Four marker compounds were verified by partial least squares discriminant analysis, and No. 9, 12 and 14 peaks were identified as geniposide, picroside Ⅱ, and picroside Ⅰ respectively. The average recoveries were in the range of 95.91%-97.31%. The HPLC fingerprint method for content determination is reliable, accurate, rapid, simple, and reproducible, and can be used as one of the effective methods to control the quality of DGD-4D.

[Glass transition of Chinese medicine extract powder and its application].

Glass transition theory is an important theory in polymer science, which is used to characterize the physical properties. It refers to the transition of amorphous polymer from the glassy state to the rubber state due to heating or the transition from rubber state to glassy state due to cooling. In this paper, the glassy state and glass transition of food and the similar relationship between the composition of Chinese medicine extract powder and food ingredients were described; the determination method for glass transition temperature (Tg) of Chinese medicine extract powder was established and its main influencing factors were analyzed. Meanwhile, the problems in drying process, granulation process and Chinese medicine extract powder and solid preparation storage were analyzed and investigated based on Tg, and then the control strategy was put forward to provide guidance for the research and production of Chinese medicine solid preparation.

[Isothermal adsorption, desorptionand thermodynamic properties of Scutellaria baicalensis pieces].

To study the characteristics of adsorption and desorption of Scutellaria baicalensis pieces. On the basic thermodynamic theory, thestatic method was adopted to obtain S. baicalensis pieces' isothermal adsorption and desorption data at 25, 35, 45 ℃, with the water activity between 0.10 and 0.85. Eight moisture models were selected to fit the data and then evaluated to determine the thermodynamic properties of S. baicalensis pieces. The results show that, among the eight adsorption models, Peleg fit the best, in which absolutely-safe and the relatively-safe moisture contents of S. baicalensis pieces were around 9.22% and 13.51% respectively; the net equivalent heat adsorption and desorption and the differential entropy of S. baicalensis pieces were closely related to moisture content, and decrease within crease of water content; when drying the pieces, 12.0% of moisture content can be taken as the drying end; both of adsorption and desorption processes were driven by enthalpy and non-spontaneous. The study on S. baicalensis pieces' isothermal adsorption and desorption rules can help advance studies on adsorption and desorption rules of Chinese herbal pieces, and play a good guiding role in optimizing storage conditions and drying process of Chinese herbal pieces.

[Effect of different DE values of malto-dextrin on properties for Schisandrae Chinensis Fructus spray-dried powder].

The purpose of this study was to compare the effect of different DE values of malto-dextrin on Schisandrae Chinensis Fructus spray-dried powder. The glass transition temperature (Tg) of the spray-dried powder, powder properties and microscopic morphology were determined, and then the moisture absorption isotherms and the glass transition temperature were used to predict its storage stability. The study showed that after adding malto-dextrin, the powder rate was increased; moisture content was decreased; Tg was increased; mobility got better; produced spherical microstructure; and Tg was increased with the decrease of DE value. The water activity-equilibrium moisture content (aw-EMC) relationship in GAB models showed, the moisture absorption of powder was increased with the rising of DE value; and the equilibrium moisture content-glass transition temperature (EMC-Tg) relationship in Gordon-Taylor models showed that, Tg was decreased with the increase of moisture content. As a result, the storage critical condition of the spray-dried powder was improved, and along with the decrease of DE value, the critical water activity and the critical water content were increased. Therefore, the smaller the DE value, the greater the stability of the spray-dried powder.

[Thermodynamic analysis of water adsorption and desorption process of Chinese herbal decoction pieces].

Based on the basic theory of thermodynamics, the thermodynamic parameters and related equations in the process of water adsorption and desorption of Chinese herbal decoction pieces were established, and their water absorption and desorption characteristics were analyzed. The physical significance of the thermodynamic parameters, such as differential adsorption enthalpy, differential adsorption entropy, integral adsorption enthalpy, integral adsorption entropy and the free energy of adsorption, were discussed in this paper to provide theoretical basis for the research on the water adsorption and desorption mechanism, optimum drying process parameters, storage conditions and packaging methods of Chinese herbal decoction pieces.

[Effect of air humidity on traditional Chinese medicine extract of spray drying process and prediction of its powder stability].

In order to solve the adhesion and the softening problems of traditional Chinese medicine extract during spray drying, a new method of adding dehumidified air into spray drying process was proposed, and the storage stability conditions of extract powder could be predicted. Kouyanqing extract was taken as model drug to investigate on the wet air (RH = 70%) and dry air conditions of spray drying. Under the dry air condition, the influence of the spray drying result with different air compression ratio and the spray-dried powder properties (extract powder recovery rate, adhesion percentage, water content, angle of repose, compression ratio, particle size and distribution) with 100, 110, 120, 130, 140 °C inlet temperature were studied. The hygroscopic investigation and Tg value with different moisture content of ideal powder were determined. The water activity-equilibrium moisture content (aw-EMC) and the equilibrium moisture content-Tg (EMC-Tg) relationships were fitted by GAB equation and Gordon-Taylor model respectively, and the state diagram of kouyanqing powder was obtained to guide the rational storage conditions. The study found that in the condition of dry air, the extract powder water content decreased with the increase of air compression ratio and the spray drying effect with air compression ratio of 100% was the best performance; in the condition of wet air, the extract powder with high water content and low yield, and the value were 4.26% and 16.73 °C, while, in the dry air condition the values were 2.43% and 24.86 °C with the same other instru- ment parameters. From the analysis of kouyanqing powder state diagram, in order to keep the stability, the critical water content of 3.42% and the critical water content of 0.188. As the water decreased Tg value of extract powder is the major problem of causing adhesion and softening during spray drying, it is meaningful to aid dehumidified air during the process.

Formulations, hemolytic and pharmacokinetic studies on saikosaponin a and saikosaponin d compound liposomes.

The aim of this study was to develop and optimise a saikosaponin a and saikosaponin d compound liposome (SSa-SSd-Lip) formulation with reduced hemolysis and enhanced bioavailability. A screening experiment was done with Plackett-Burman design, and response surface methodology of five factors (EPC/SSa-SSd ratio, EPC/Chol ratio, water temperature, pH of PBS, and ultrasound time) was employed to optimise the mean diameter, entrapment efficiency of SSa and SSd, and the reduction of hemolysis for SSa-SSd-Lip. Under the optimal process conditions (EPC/SSa-SSd ratio, EPC/Chol ratio, water temperature and pH of PBS were 26.71, 4, 50 °C and 7.4, respectively), the mean diameter, the entrapment efficiency of SSa, the entrapment efficiency of SSd and the hemolysis were 203 nm, 79.87%, 86.19%, 25.16% (SSa/SSd 12.5 mg/mL), respectively. The pharmacokinetic studies showed that the SSa-SSd-Lip had increased circulation time, decreased Cl, and increased AUC, MRT and T1/2ß (p < 0.05) for both SSa and SSd after intravenous administration in comparison with solution.

[Determination of equilibrium solubility and n-octanol/water partition coefficient of pulchinenosiden D by HPLC].

OBJECTIVE: To determine the equilibrium solubility of pulchinenosiden D in different solvents and its n-octanol/water partition coefficients. METHOD: Combining shaking flask method and high performance liquid chromatography (HPLC) to detect the n-octanol/water partition coefficients of pulchinenosiden D, the equilibrium solubility of pulchinenosiden D in six organic solvents and different pH buffer solution were determined by HPLC analysis. RESULT: n-Octanol/water partition coefficients of pulchinenosiden D in different pH were greater than zero, the equilibrium solubility of pulchinenosiden D was increased with increase the pH of the buffer solution. The maximum equilibrium solubility of pulchinenosiden D was 255.89 g x L(-1) in methanol, and minimum equilibrium solubility of pulchinenosiden D was 0.20 g x L(-1) in acetonitrile. CONCLUSION: Under gastrointestinal physiological conditions, pulchinenosiden D exists in molecular state and it has good absorption but poor water-solubility, so increasing the dissolution rate of pulchinenosiden D may enhance its bioavailability.

[Roller compaction research of Banlangen effervsce tablets].

OBJECTIVE: To study the conditions and parameters of roller compaction of Banlangen effervsce tablet. METHOD: The experimentation adopts L9 (3(4)) orthogonal experiment to study the conditions and parameters of roller compaction of Banlangen effervsce tablet; studied factors that included roller pressure, roller speed and moisture content of power, which influence the result of granule yield and granule friability. RESULT: The optimal technique is: roller pressure at 1.5 MPa; roller speed at 15 Hz; moisture content of power at 1.5%. CONCLUSION: The study of roller compaction technique of Banlangen effervsce tablets provides some technicial consults of its research and production.

[Review of effervescent technique in pharmaceutics research].

Effervescent technique, which can accelerate drug disintegration and dissolution, is usually applied in quick release preparations. Along with the development of pharmaceutical technique and theory, effervescent technique is used more and more extensively to adjust the behavior of drug release, such as in sustained and controlled release preparations, pulsatile drug delivery systems, and so on. This review demonstrated the new applying of effervescent technique in effervescent tablets, stomach floating forms, osmotic pump tablets and pulsatile drug delivery systems, adding to the critical common technique of effervescent forms in drug research. This will be benefit for the further research and development of effervescent technique.