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Based on the dual needs of analgesia and anti-inflammation in trauma treatment, this study uses acetaminophen and moxifloxacin hydrochloride as active pharmaceutical ingredients and develops a composite bilayer tablet with a dual-phase drug release system by using binder jet 3D printing technology. Due to the complexity of the 3D printing process, there is an interaction between the various parameters. Through the optimization of the process, the relationship between the key process parameters can be determined more intuitively. In this study, the process of extended-release tablets was optimized to maintain the mechanical properties of the tablets while realizing the regulation of release. The full-factor experimental design of three central points 23 was used to analyze the factors that significantly affect the quality attributes of extended-release tablets and the interaction between factors. The optimal extended-release process parameters were obtained by the response optimizer: the inkjet quantity of the printing ink was 10 (about 13.8 pL), the powder thickness was 180 μm, and the running speed was 360 mm·s-1. The in vitro of release of 3D printed composite bilayer tablets showed that the in vitro of release of 3D printed tablets and commercially available tablets conformed to the Ritger-Peppas release model. The results of porosity showed that the immediate-release layer of the preparation has many pores and large pore size, and the dissolution of the immediate release layer within 15 min was greater than 85%. The internal pore size of the extended release layer is large, but it can still release slowly for up to 8 h, the mechanism may be related to the extended release of HPMC gelation. On the basis of verifying the rationality of the design goal of 3D printed composite bilayer tablets, this study also provides a theoretical basis for the preparation of 3D printing complex preparations.
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ObjectiveTo investigate the intestinal absorption characteristics of multi-index components in Danggui Buxuetang with drug absorption simulating system （DASS） established by everted intestinal sac model. MethodThe intestinal absorption solution at different time points after administration of Danggui Buxuetang was collected and detected by high performance liquid chromatography （HPLC）， acetonitrile （A）-0.2% glacial acetic acid solution （B） was used as the mobile phase for gradient elution （0-16 min， 15%-23%A； 16-20 min， 23%-28%A； 20-25 min， 28%-30%A； 25-30 min， 30%A； 30-35 min， 30%-65%A； 35-45 min， 65%-95%A）， the detection wavelength was 302 nm. HPLC fingerprint of intestinal absorption solution was established and the common peak was calibrated， and the relative cumulative absorption rate of each index component was calculated. The relative cumulative absorption curves of components were fitted with various mathematical models by DDSolver 1.0 to explore the absorption law of different components. ResultThe absorption process of C2 （calycosin-7-glucoside） and C6 in Danggui Buxuetang was in line with zero-order equation， C9 was best fitted by Weibull equation， and the remaining 7 components were in line with Makoid-Banakar equation. C1 with C2， C3， C5， C7 and C10， C2 with C5 and C7， C3 with C4， C5， C7 and C10， C4 with C6 and C10， C5 with C7， C6 with C10， C7 with C10， C8 with C9 were absorbed simultaneously during the absorption process. With the prolongation of time， the overall cumulative absorption rate of Danggui Buxuetang increased. At 120 min， the overall cumulative absorption rate of Danggui Buxuetang exceeded 38%， and reached 49.14% at 180 min. ConclusionTen ingredients in Danggui Buxuetang are absorbed in the jejunum， but absorption law of various components is different， which shows that the intestinal absorption of compound preparations of traditional Chinese medicine （TCM） has multiple characteristics. Intestinal absorption study of TCM compound preparations with chemical composition as the index can reveal some of its absorption law， but it is not complete.
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The present study explored the kinetics and variation of volatile components of Atractylodis Macrocephalae Rhizoma during the hot-air drying process to obtain the optimal process parameters under multiple goals such as drying efficiency and drying quality. The dry basis moisture content and drying rate curves along with the change of drying time of Atractylodis Macrocephalae Rhizoma were investigated at five levels of drying air temperatures(30, 40, 50, 60, and 70 ℃). The relationship between moisture ratio and time in the drying process of Atractylodis Macrocephalae Rhizoma was fitted and verified by Midilli model, Page model, Overhults model, Modified Page model, Logaritmic model, Two terms Exponential model, and Newton model. Meanwhile, the effective diffusion coefficient of moisture(D_(eff)) and activation energy(E_a) in Atractylodis Macrocephalae Rhizoma were calculated under different drying air temperatures. GC-MS was used to determine the volatile components and content changes of the fresh Atractylodis Macrocephalae Rhizoma and dried products at different temperatures. The dry basis moisture content and drying rate of Atractylodis Macrocephalae Rhizoma were closely related to the temperature of the drying medium, and the moisture of the Atractylodis Macrocephalae Rhizoma decreased with the prolonged drying time. As revealed by the drying rate curve, the drying rate increased with the increase in hot air temperature, and the migration of moisture was accelerated. The comparison of the correlation coefficient(R~2), chi-square(χ~2), and root mean standard error(RMSE) of each model indicated that the parameter average of the Midilli model had the highest degree of fit, with R~2=0.999 2, χ~2=8.78×10~(-5), and RMSE=8.20×10~(-3). Besides, the D_(eff) at 30-70 ℃ was in the range of 1.04×10~(-9)-6.28×10~(-9) m~2·s~(-1), and E_a was 37.47 kJ·mol~(-1). The volatile components of fresh Atractylodis Macrocephalae Rhizoma and dried products at different temperatures were determined by GC-MS, and 18, 18, 18, 17, 17, and 18 compounds were identified respectively, which accounted for more than 84.76% of the volatile components. In conclusion, the hot-air drying of Atractylodis Macrocephalae Rhizoma can be model-fitted and verified and the variation law of the moisture and volatile components of Atractylodis Macrocephalae Rhizoma with temperature is obtained. This study is expected to provide new ideas for exploring the drying characteristics and quality of aromatic Chinese medicine.
Subject(s)
Atractylodes , Drugs, Chinese Herbal , Hot Temperature , Kinetics , RhizomeABSTRACT
Objective: The moisture absorption of Rhei Radix et Rhizoma (RRR) with different initial moisture content was studied under the conditions of relative humidity of 20%-85% and temperature of 5, 15, 25 and 35 ℃, respectively, so as to provide reference for the control of safe storage moisture and reasonable storage of RRR. Methods: RRR was stored at temperature of 5, 15, 25 and 35 ℃ and humidity of 45%, 60% and 75%, respectively. The samples were taken at different time points to determine its safe water activity with powder color and mildew as indicators. The isotherm adsorption data of RRR at 5, 15, 25 and 35 ℃ and water activity of 0.2-0.8 were obtained by static weighing method and six isotherm adsorption models, GAB, Oswin, Smith, Halsey, Henderso and Peleg, were used for fitting and evaluation. Results: The absolute safe water activity and relative safe water activity of RRR were 0.5 and 0.6, respectively. The adsorption isotherms of RRR at 5, 15, 25 and 35 ℃ were "S" type, which belonged to type II isotherm. Oswin model was the best fitting model and the model expression was: Meq=A[Aw/(1-Aw)B. According to the model, the absolute safe water content of RRR with different initial moisture content at 5 ℃ was 9.00%, 9.59%, 8.00%, 6.71% and relative safe water content was 10.17%, 10.89%, 9.20% and 8.07%, respectively; The absolute safe water content of RRR with different initial moisture content at 15 ℃ was 8.24%, 8.83%, 7.24%, 5.86% and relative safe water content was 9.57%, 10.17%, 8.59% and 7.20%, respectively; The absolute safe water content of that at 25 ℃ was 7.17%, 7.75%, 5.73%, 4.70% and the relative safe water content was 8.72%, 9.26%, 7.26% and 6.25%, respectively; The absolute safe water content of that at 35 ℃ was 8.00%, 8.45%, 6.53%, 5.21% and the relative safe water content was 9.74%, 9.85%, 8.40%, 7.27%, respectively. Conclusion: Oswin model can be used to predict the equilibrium moisture content of RRR in storage, which can provide reference for the control of safe moisture and scientific maintenance of RRR.
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Objective: The objective of this study was to design and evaluate controlled release mucoadhesive microspheres of lamivudine using mucoadhesive polymers and mucilage. Methods: Mucoadhesive microspheres of lamivudine were formulated by ionic gelation method. The response surface methodology was adapted for optimization of formulation using central composite design (CCD) for two factors at three levels each was employed to study the effect of independent variables, Sodium alginate-drumstick mucilage (X1) and calcium chloride (CaCl2) concentration (X2) on dependent variables, namely drug encapsulation efficiency (DEE) and particle size (PS). Optimized drumstick mucilage mucoadhesive microspheres of lamivudine were obtained by using numerical optimization of desirability approach. The observed microspheres were coincided well with the predicted values by the experimental design. Results: The microspheres formed were spherical in shape, and Particle size (PS) ranged between 681.63-941.57μm. Drug encapsulation efficiency (DEE) was ranged between 69.63-94.56 %. The drug release for an optimized formulation was 96.58 %. The mechanism of drug release from microspheres followed Korsemeyer’s-Peppas and exponential ‘n’ value was greater than 0.45, indicating the drug release was non-fickian i.e., swelling followed by erosion mechanism. Conclusion: This work suggests that mucoadhesive microspheres, an effective drug delivery system for lamivudine, can be prepared using drumstick mucilage in improving the bioavailability of the drug.
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To understand the management level and international positioning of Chinese hospitals, we devel-oped a comprehensive survey instrument of chinese hospital management survey following the well-adapted methodolo-gy of world management survey which has been widely used internationally. The survey was conducted on 20 manage-ment practices covering four major management dimensions including operations management, performance manage-ment, target management and talent management respectively. Based on the CHMS structure and setting, the four-di-mension and twenty-item management model was analyzed with construct validity test. From the test, the middle level managers were recruited from more than 400 chinese national representative hospitals. The results showed that the chi-square/degree of freedom (CMIN/DF) is 2. 209, and RMSEA (root mean square error approximate) is 0. 039, indicating a good model fitting. The further indications of model fit such as GFI, IFI and CFI were all above 0. 9 which is the typical benchmark for model acceptance. This study provides evidence for correspondence between con-ceptual and empirical hospital management and the insight of model fitting on the current data. The results conclude that CHMS has satisfied validation in Chinese hospital management practices, and can be used as an effective sur-vey method to assess the level of Chinese hospital management and to provide a general platform for international comparison.
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AIM To fit the moisture adsorption models for Astragali Radix aqueous extract.METHODS For the aqueous extract prepared by decocting,the moisture adsorption kinetics curve and adsorption/desorption isotherms were drawn by gravimetry,and then the data on moisture adsorption were fitted.The fitted models were optimized according to evaluation indices of root mean square error (RMSE),residual sum of squares (RSS) and coefficient of determination (R2).RESULTS The double exponential model for moisture adsorption kinetics curve and Peleg model for adsorption/desorption isotherms were considered as the two best models with regard to their fitting effects (R2 values were the closest to 1,RMSE and RSS values were the closest to 0).Among them,various adsorption/desorption isotherms all belonged to type Ⅱ ("S" isotherm),while the higher equilibrium moisture content of desorption isotherm than that of adsorption isotherm contributed to obvious type H3 hysteresis phenomenon.CONCLUSION Double exponential model and Peleg model can well fit the moisture adsorption kinetics curve and adsorption/desorption isotherms of Astragali Radix aqueous extract,respectively.