Synthesis and characterization of chitosan-PVA hydrogel containing PEGylated recombinant epidermal growth factor on cell culture for wound healing substitute

Abstract The aim of the current study was to assess the physicochemical characteristics and wound healing activity of chitosan-polyvinyl alcohol (PVA) crosslinked hydrogel containing recombinant human epidermal growth factor (rh-EGF) or recombinant mouse epidermal growth factor (rm-EGF). The hydrogels were prepared and analyses were made of the morphological properties, viscosity, water absorption capacity, mechanical and bio-adhesive properties. The viscosity of the formulations varied between 14.400 - 48.500 cPs, with the greatest viscosity values determined in K2 formulation. F2 formulation showed the highest water absorption capacity. According to the studies of the mechanical properties, H2 formulation (0.153±0.018 N.mm) showed the greatest adhesiveness and E2 (0.245±0.001 mj/cm2) formulation, the highest bio-adhesion values. Hydrogels were cytocompatible considering in vitro cell viability values of over 76% on human keratinocyte cells (HaCaT, CVCL-0038) and of over 84% on human fibroblast cells (NIH 3T3, CRL-1658) used as a model cell line. According to the BrdU cell proliferation results, B1 (197.82±2.48%) formulation showed the greatest NIH 3T3 and C1 (167.43±5.89%) formulation exhibited the highest HaCaT cell proliferation ability. In addition, the scratch closure assay was performed to assess the wound healing efficiency of formulation and the results obtained in the study showed that F2 formulation including PEGylated rh-EGF had a highly effective role.

Scientific Characterization of Traditional Softening Method of Corydalis Rhizoma / 中国实验方剂学杂志

ObjectiveModern scientific methods and techniques were used to scientifically characterize the traditional softening process of Corydalis Rhizoma， so as to clarify the scientificity and rationality of the traditional process， and provide reference for inheriting the processing methods and experience of traditional Chinese medicine. MethodLow-field nuclear magnetic resonance imaging （LF-NMR/MRI） was used to characterize the water types and distribution in the softening process of Corydalis Rhizoma. Samples during the softening process was cut into thick slices and its section was observed by stereoscopic microscope. High performance liquid chromatography （HPLC） was employed to determine the content change of tetrahydropalmatine during the softening process with the mobile phase of methanol-0.1% phosphoric acid solution （60∶40， triethylamine regulated to pH 6.5） and detection wavelength at 280 nm. The determination method of softening endpoint of Corydalis Rhizoma was simulated by texture analyzer （hand pinch method）， and the softening degree of the finished products was determined after optimizing the relevant parameters. ResultLF-NMR/MRI showed that the water could penetrate through the core and distribute evenly in Corydalis Rhizoma softened by Zhangbang method. The water first entered into the medicinal material from the epidermis and stem marks in the soaking stage as the form of free water， and then penetrated into the inner core to achieve redistribution in the moistening stage. Under stereoscopic microscope， it was observed that Corydalis Rhizoma softened by the Zhangbang method could be sliced well， but the core bursting slices were easy to appear if the softening time was not enough， and the softening of samples was caused by the keratine-like powder after absorbing water. HPLC measurement showed that the loss of tetrahydropalmatine in the softening method was small， its content decreased about 5% in the soaking process， and its content was almost unchanged during the moistening process. The softening degree of Corydalis Rhizoma could be quantified by the texture analyzer， and the optimum parameters were 2 mm·s-1 of speed before test， test speed and speed after test， 20 g of the trigger force， 20% of compression degree. The compressive force of the qualified softened Corydalis Rhizoma was 12.75-15.69 N with the relative standard deviation （RSD） of 6.8%. ConclusionModern scientific methods and techniques can characterize the scientificity and rationality of the traditional processing methods， and confirm that the Zhangbang softening method has the advantages of high efficiency， convenience and small loss of index components. The texture analyzer can simulate the softening endpoint judgment method （hand pinch method）， and realize the goal from subjective experience judgment to objective technology quantification， which has a good demonstration role for the modern inheritance of traditional processing technology.

Scientific Characterization of Traditional Softening Method of Corydalis Rhizoma / 中国实验方剂学杂志

ObjectiveModern scientific methods and techniques were used to scientifically characterize the traditional softening process of Corydalis Rhizoma， so as to clarify the scientificity and rationality of the traditional process， and provide reference for inheriting the processing methods and experience of traditional Chinese medicine. MethodLow-field nuclear magnetic resonance imaging （LF-NMR/MRI） was used to characterize the water types and distribution in the softening process of Corydalis Rhizoma. Samples during the softening process was cut into thick slices and its section was observed by stereoscopic microscope. High performance liquid chromatography （HPLC） was employed to determine the content change of tetrahydropalmatine during the softening process with the mobile phase of methanol-0.1% phosphoric acid solution （60∶40， triethylamine regulated to pH 6.5） and detection wavelength at 280 nm. The determination method of softening endpoint of Corydalis Rhizoma was simulated by texture analyzer （hand pinch method）， and the softening degree of the finished products was determined after optimizing the relevant parameters. ResultLF-NMR/MRI showed that the water could penetrate through the core and distribute evenly in Corydalis Rhizoma softened by Zhangbang method. The water first entered into the medicinal material from the epidermis and stem marks in the soaking stage as the form of free water， and then penetrated into the inner core to achieve redistribution in the moistening stage. Under stereoscopic microscope， it was observed that Corydalis Rhizoma softened by the Zhangbang method could be sliced well， but the core bursting slices were easy to appear if the softening time was not enough， and the softening of samples was caused by the keratine-like powder after absorbing water. HPLC measurement showed that the loss of tetrahydropalmatine in the softening method was small， its content decreased about 5% in the soaking process， and its content was almost unchanged during the moistening process. The softening degree of Corydalis Rhizoma could be quantified by the texture analyzer， and the optimum parameters were 2 mm·s-1 of speed before test， test speed and speed after test， 20 g of the trigger force， 20% of compression degree. The compressive force of the qualified softened Corydalis Rhizoma was 12.75-15.69 N with the relative standard deviation （RSD） of 6.8%. ConclusionModern scientific methods and techniques can characterize the scientificity and rationality of the traditional processing methods， and confirm that the Zhangbang softening method has the advantages of high efficiency， convenience and small loss of index components. The texture analyzer can simulate the softening endpoint judgment method （hand pinch method）， and realize the goal from subjective experience judgment to objective technology quantification， which has a good demonstration role for the modern inheritance of traditional processing technology.

Research on batch-to-batch quality control of compound Danshen extract based on physical characterization and multivariate statistical analysis / 中国中药杂志

Physical attributes of Chinese herbal extracts are determined by their chemical components, and the physical and chemical attributes jointly affect the preparation process performance and the final product quality. Therefore, in order to improve the quality control of Chinese herbal extracts, we should comprehensively study the batch-to-batch consistency of physical and chemical attributes as well as the correlations between them. This paper first explored the physical attributes affecting the preparation process performance of the compound Danshen extract and developed a method for characterizing the texture attributes. With such main chemical components as water, phenolic acids, saponins, and saccharides and texture, rheology, and other physical attributes taken into consideration, the batch-to-batch quality fluctuation of products from different production lines and time was analyzed by principal components analysis(PCA). Finally, the correlation and partial least squares(PLS) analysis was conducted, and the regression equation was established. The fitting result of the PLS model for dynamic viscosity was satisfying(R~2Y=0.857, Q~2=0.793), suggesting that the chemical components could be adjusted by the component transfer rate in the extraction process, the impurity removal rate in the alcohol precipitation process, and the water retention rate of the concentration process to meet the control of the extract dynamic viscosity. This study clarified the correlations between physical and chemical attributes of the compound Danshen extract and established a method for controlling its physical attributes based on process regulation, which would provide reference for improving the quality control of Chinese herbal extracts.

Application Progress of Texture Analyzer in Pharmaceutical Preparation Research / 中国实验方剂学杂志

Texture analyzer is a multifunctional physical property analyzer. Through a variety of test modes such as compression， puncture， shearing and stretching， hardness， adhesion， elasticity， cohesiveness and other physical property parameters are characterized. The results are objective， sensitive， and accurate， which can provide theoretical basis and reference for interpretation of basic theoretical， optimization of prescription technology and quality control research of pharmaceutical preparations. Firstly， the principles， test modes， measurement indexes and measurement data analysis methods of texture analyzer were summarized in this paper. Secondly， the application progress of texture analyzer in solid preparations， semi-solid preparations， liquid preparations， traditional Chinese medicine decoction pieces and their intermediates was described in detail， and compared with the commonly used measurement methods of physical property indicators. Finally， the application prospects of texture analyzer and its research contents to be improved were reviewed， so as to facilitate the use of texture analyzer by pharmaceutical researchers to promote the development of related fields of pharmaceutics， and to provide new ideas and methods for the research and development of pharmaceutical preparations.

Advance in quality assessment of Chinese materia medica using microscopic and morphological methods / 中国天然药物

Quality evaluation plays a vital role in ensuring safety and effectiveness of Chinese materia medica (CMM). Microscopic and morphological technologies can be used to distinguish CMM's characteristics, such as shape, size, texture, section, and smell, for authenticity and quality control of CMM. The microscopic and morphological applications of novel micro-technology, colorimeter, and texture analyzer for CMM identification are summarized and the future prospect is discussed in this paper. Various styles and complex sources of CMM are systemically reviewed, including cormophyte medicinal materials, fruit and seeds, pollen grain, and spore materials.