Baicalein-modified chitosan nanofiber membranes with antioxidant and antibacterial activities for chronic wound healing.

Diabetic foot ulcers, burns and many other trauma can lead to the formation of skin wounds, which often remain open for a long period of time, seriously affecting the quality of patient's life. Oxidative stress and infection are the main factors affecting the healing of chronic wounds, so it is important to develop dressings with dual antioxidant and antimicrobial properties for wound management. In this study, functionalized chitosan was synthesized by modifying chitosan with antioxidant baicalein to enhance the antimicrobial and antioxidant activities of chitosan. Then the obtained baicalein-modified chitosan was prepared into nanofibrous membranes by electrospinning. The membrane structures were characterized, and the antioxidant and antibacterial activities were evaluated by in vivo and in vitro experiments. The results showed that the prepared wound dressings had excellent antioxidant and antibacterial activities and significantly accelerated the wound process. This study provided a reference for the development of novel dressing materials to promote wound healing.

HPLC combined with chemometrics for quality control of Huamoyan Granules or Capsules.

Objective: Huamaoyan Granules (HMYG) and Huamaoyan Capsules (HMYC) are Chinese patent medicines with different dosage forms of the same prescription. Due to the different preparation process, the chemical composition of these Chinese patent medicines varies greatly among different forms, but there were few studies on the difference comparison and quality control of them. In order to improve the effectiveness and safety in its clinical application, an idea combining high performance liquid chromatography (HPLC) and chemometrics was put forward to study the quality control of Chinese patent medicines in different dosage forms of the same prescription. Methods: The differential markers of HMYG and HMYC were explored based on HPLC fingerprint and chemometrics including orthogonal projections to latent structures-discriminant analysis (OPLS-DA), principal component analysis (PCA), and hierarchical cluster analysis (HCA). Finally, the quantitative analysis method of related components was established by HPLC. Results: A quality control method for HMYG and HMYC was established. Firstly, the chemical components of HMYG and HMYC were systematically analyzed by HPLC fingerprinting. Further exploration showed that there were 20 characteristic peaks and 57 common peaks. Then, the potential differential markers between HMYG and HMYC were explored by chemometrics, and the differential markers were screened after intersection with the 20 characteristic peaks. Finally, HPLC quantitative analysis methods for nine components were established, including seven differential markers (neochlorogenic acid, protocatechualdehyde, chlorogenic acid, cryptochlorogenic acid, caffeic acid, rosmarinic acid and salvianolic acid A). The results of HPLC quantitative analysis showed that the contents of eight components in HMYG and HMYC samples were significantly different. According to the above results, the differential markers between HMYG and HMYC screened based on HPLC fingerprint and chemometrics can effectively characterize the differences between the two dosage forms. Conclusion: The present work provides a rapid and effective method for routine quality evaluation and control of HMYG and HMYC. This work also provides feasible methods for the quality evaluation and control of Chinese patent medicines with different dosage forms of the same prescription.

Study of the permeation-promoting effect and mechanism of solid microneedles on different properties of drugs.

In transdermal drug delivery systems, the physicochemical properties of the drug affect its percutaneous permeability. However, whether the physicochemical properties of drugs change their transdermal permeability in the presence of pores in the presence of solid microneedles (MNs) has been less studied in this area. In this project, cinnamaldehyde, curcumin, ferulic acid and geniposide were selected as model drugs for the study of their transdermal permeability under the action of MNs, and a combination of classical experiments and visualization means such as scanning electron microscopy and laser confocal was used to investigate the permeation-promoting mechanism of MNs. The results showed that the MNs had significant permeation-promoting effects on different properties of drugs, with the permeation-promoting effects on cinnamaldehyde, curcumin, ferulic acid and geniposide being 6.36, 17.43, 29.54 and 8.91 times, respectively, and the permeation-promoting effects were more pronounced for lipid-soluble and amphiphilic drugs. Using scanning electron microscopy, transmission electron microscopy and other means to confirm that MNs can promote the penetration by acting on the skin to produce pores, and their effect on skin structure is greater than that of drugs. In addition, the existence of pores increases the amount of drug transdermal, which may enhance the diffusion of drug on the skin, and has no effect on lipid exchange and transdermal route. Through the research, it has been found that MNs is equivalent to direct peeling of the stratum corneum (SC), but it is simpler and safer for the patient.

[Analysis on quality value transfer of substance benchmarks of Qingwei San].

By preparing 10 batches of substance benchmarks freeze-drying powder( lyophilized powder),the methodology of the characteristic spectrum and the content of index component for substance benchmarks of Qingwei San was established. The characteristic peaks and the similarity range of the characteristic spectrum,the contents and the transfer rate range of isoferulic acid,palmatine and paeonol,and the paste-forming rate range were determined to define key quality attributes of substance benchmarks of Qingwei San. In the10 batches of substance benchmarks of Qingwei San,the similarity of characteristic spectrum was higher than 0. 90. In further comparison of the characteristic peak information,a total of 16 characteristic peaks were identified,including 5 characteristic peaks from Cimicifugae Rhizoma,5 characteristic peaks from Coptidis Rhizoma,2 characteristic peaks from Angelicae Sinensis Radix and 4 characteristic peaks from Moutan Cortex. The content of isoferulic acid was 0. 10%-0. 18%,with the average transfer rate of 49. 82%±4. 02%. The content of palmatine was 0. 17%-0. 31%,with the average transfer rate of 15. 84% ±2. 39%. The content of paeonol was 0. 41%-0. 75%,with the average transfer rate of 23. 41%±3. 23%. The paste-forming rate of the 10 batches of substance benchmarks were controlled at 27%-33%,with the transfer rate between the theoretical paste-forming rate and the actual paste-forming rate was 86. 59%±3. 39%. In this study,the quality value transfer of substance benchmarks of Qingwei San was analyzed by the combination of characteristic spectrum,the content of index component and the paste-forming rate. A scientific and stable evaluation method was preliminarily established,so as to provide the basis for subsequent development and quality control of relevant preparations of Qingwei San.