Electrospray ionization (ESI) is easy to be affected by the biological matrix interferences, and thus the accuracy, precision, and reproducibility of the quantitation are significantly impaired. Probe electrospray ionization (PESI) is one of the most typical ambient ionization, which can ionize molecules without complicated sample preparation at the atmospheric environment, and is superior in simplicity, high efficiency, and high throughput. The micro pen electrospray ionization tandem mass spectrometry (μPen-ESI-MS/MS) method was newly developed based on PESI. In this study, the matrix effect of the μPen-ESI-MS/MS method for drug quantitation in plasma samples was evaluated and compared with the liquid chromatography coupled with electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) method. The μPen-ESI-MS/MS and LC-ESI-MS/MS methods for quantitation of five drugs in rat plasma were established respectively, and the matrix factors (MFs) and internal standard normalised matrix factors (IS normalised MFs) were measured. The results showed that the ion suppression of the μPen-ESI-MS/MS method for tacrolimus, flunarizine, and desloratadine was equal to or less than that of the LC-ESI-MS/MS method; the RSDs of the IS normalised MFs of all five drugs were less than 15%, which met the related requirements of the Pharmacopoeia of the People's Republic of China. Therefore, this study investigated the matrix effect of the μPen-ESI-MS/MS method for quantitative analysis of target drugs in plasma samples and provided new data for the application of μPen-ESI-MS/MS in bioanalysis.

The purpose of the study was to investigate the thermal expansion characteristics of brivaracetam form Ⅰ, and explore the influence mechanism of the crystal structure on its thermal expansion behavior. The crystal structure of brivaracetam form Ⅰ was characterized by X-ray single crystal diffraction and variable temperature X-ray powder diffraction at different temperatures. The interaction energy of brivaracetam molecule calculated by B3LYP/6-31G(d, p) wave function with the aid of CrystalExplorer 21.5 software. The results show that brivaracetam form Ⅰ exhibits significant reversible anisotropic thermal expansion under the temperature range of 123-323 K. The principal expansion X₁, X₂, X₃ axes are approximately aligned with the a, b and c axes of the unit cell, and the thermal expansion coefficients of the principal expansion axes are -127.61×10^-6, 95.96×10^-6, 233.80×10^-6 K^-1, respectively. The a-axis exhibits negative expansion characteristics. The volumetric thermal expansion coefficient is 202.17×10^-6 K^-1. The energy framework of the crystal is obvious layered, and the interaction energy between layers is weak, which leads to a significant linear positive expansion in the c-axis direction of the unit cell. Through a combination of experimental and theoretical methods, the thermal expansion characteristics of brivaracetam form Ⅰ are systematically analyzed, and the influence mechanism of the crystal structure on its thermal expansion behavior is explored, which has certain guiding significance for the production process of tablet preparations in practice.

To profile and characterize the ingredients absorbed into blood and their metabolites of the Eucommiae Cortex (EC) extracts in rats with renal fibrosis induced by adenine, and so as to provide a reference for investigation of the pharmacodynamic substances of EC. SD rats with renal fibrosis induced by adenine were intragastrically administered with the EC extracts, and the rat plasma samples were collected and analyzed by UHPLC-Q-TOF-MS/MS to identify the prototype ingredients absorbed into blood and their metabolites. The experiment was approved by the experimental Animal Ethics Committee from Nanjing University of Chinese Medicine (No. 202103A008). The results showed that a total of 24 prototype compounds were identified, including 9 lignans, 4 iridoids, 8 phenylpropanoids, and 3 organic acids. Furthermore, 30 metabolites were obtained by further analysis, including 9 lignans, 19 iridoids, and 2 organic acids. The results of this study can provide the valuable reference for further elucidation of the pharmacodynamic substantial basis and mechanism of EC in the treatment of renal fibrosis.

The development of the manufacturing process may require considerable time and resources from an economic perspective, which may result from the lack of cost-effective and reliable modeling tools of unit operation development in the pharmaceutical industry, in contrast to other chemical industries. Therefore, it is necessary to apply the modeling tools to the process, not only to overcome the challenges of regulatory and economic aspects but also to develop a more efficient and robust process. In response to this necessity, the modeling of the manufacturing process has been become increasingly important, as it can be applied to equipment design, improving process efficient, scale-up and unit operation development in the pharmaceutical industry. Discrete element method is a numerical method for predicting mechanical dynamics, such as position, velocity and motion of individual particles. First of all, the input parameters related to particle contact should be clearly defined. In this work, a calibration method of discrete element parameters was established and then elucidated the effects of different testing methods on repose angle of microcrystalline cellulose (MCC), from mesoscale angle. This experiment was composed of three parts: ① Angle of repose measured by the lifting cylinder method (θ) was regarded as the response value of the model, and then discrete element simulation parameters were screened and optimized by Plackett-Burman, steepest climb and Box-Behnken test designs; ② The robustness of previous model was assessed by angle of repose measured by the funnel injection method (α) and the shear box method (φ) to obtain the best parameter combination generated from the model; ③ Based on accurate and reliable microscopic parameters, the formation mechanism of angle of repose was comprehensively investigated from the mesoscopic-angle perspective. The calibration results showed a robust and reliable parameter combination. Moreover, the lifting speed of lifting cylinder method and the height of funnel injection method all had a certain impact on the measurement results of angle of repose. Interesting, the evolution of force chains in the process of stacking with different angle of repose revealed a certain law in the perspective of mesoscopic-angle. Thus, the objective of present work is to provide a reference for discrete element simulation parameter calibration of other solid preparations and accurate simulation of materials in the pharmaceutical process such as mixing, transferring and tablet pressing.

The emergence of antibiotic-resistant strains seriously reduces the efficiency of traditional antibiotic therapy. The development of a new alternative antibiotic method to effectively eliminate this bacterial infection has become a critical issue. Photothermal therapy (PTT) has shown many advantages in tissue penetration, spatiotemporal specificity, no drug resistance and broad-spectrum antimicrobial ability. However, extremely high temperature (55-65 ℃) is needed to achieve highly efficient bactericidal effect during PTT treatment process. Thus, this procedure will inevitably cause collateral damage to normal tissues. Silver nanoparticles (AgNPs) are one of the most commonly used broad-spectrum antimicrobial agents. Its antimicrobial activity is mainly derived from the release of silver ions (Ag⁺). However, excessive AgNPs not only would cause toxic to the body, but also waste precious metals. In this study, oxidized mesoporous carbon nanospheres (OMCN) were used as photothermal materials to prepare OMCN-Ag⁺ composites. The composite material can improve the antibacterial activity, reduce the waste of metal Ag and decrease the toxic and side effects. Moreover, the precisely controlled mild heat can overcome the shortcoming such as the damage to normal tissue caused by the excessive temperature during traditional photothermal antimicrobial process. The antimicrobial treatment system exhibits a good biocompatibility both in vitro and in vivo. Specially, the designed nanosytem can effectively eliminate the bacteria from the infected wound, subsequently promoting the process of wound healing. All animal experiments were carried out with approval of the Animal Experiment Ethics Committee of Henan University.

Lornoxicam (LOR) is a nonsteroidal anti-inflammatory drug with analgesic, anti-inflammatory and antipyretic effects. As a biopharmaceutics classification system (BCS) class Ⅱ drug, it has poor aqueous solubility and then low bioavailability after oral administration. In addition, the tabletability of LOR itself is also poor and could not form the tablet after compression, which seriously limits the development of its oral solid dosage. The current study aims to improve dissolution and tabletability of LOR by cocrystallization technique with small molecule puerarin (PUE). LOR cocrystal with the co-former PUE was prepared via the solvent-evaporation method and characterized by powder X-ray diffraction, differential scanning calorimetry, Fourier transform infrared spectroscopy and thermo-gravimetric analyzer. The dissolution behavior, tabletability and stability of the prepared cocrystal were also further investigated. In comparison to pure LOR, LOR-PUE cocrystal showed higher apparent and intrinsic dissolution rate. Moreover, after cocrystallization, the solubility of LOR and PUE showed 4.0-fold and 1.5-fold increase compared to the raw ones in water, respectively. LOR-PUE cocrystal showed significantly improved tabletability compared to LOR alone under a wide compression range of 75-375 MPa. In addition, such cocrystal exhibited superior chemical stability with no change of drug contents for at least 60 days under the conditions of 40 ℃ and 25 ℃/75% RH.

In this study, a novel nano-drug delivery system, namely hybrid exosome, was constructed via membrane self-assembly of pancreatic cancer cell-derived exosomes with liposomes, which inherits the functionalities of exosomes, including high affinity, good stability and low immunogenicity, but also unites the characteristic of liposomes (e.g., long circulation time, high loading ability) to achieve precise drug navigation and minimum adverse effects. Specifically, two different preparation methods—repeated freeze-thawing and 37 ℃ incubation were used to fabricate hybrid exosomes at laboratory scale. Comparative analysis and characterization of these synthesized samples were performed based upon size, zeta potential and membrane fusion efficiency. The results showed that the highest exosome yield was attainted after culture for 48 h, with the exosome yield of 0.83 ± 0.07 mg/10⁸ cells for HuP-T3 cell line and 0.79 ± 0.10 mg/10⁸ cells for Panc0403 cell line. Hybrid exosomes obtained by freeze-thaw method were shown to have higher membrane fusion rate, lower size and polydispersity index (PDI), higher zeta potential and relative more stable, as compared with that made by incubation at 37 ℃ for 12 h, indicating the former approach is more suitable to construct hybrid exosomes with desirable physicochemical properties. This result may provide a preliminary experimental basis for the subsequent delivery of different anticancer drugs for the treatment of solid tumors such as pancreatic cancer.

To investigate the effect of ionic liquid based on choline and citronellic acid ([Cho] [CA], COCA) on the oral absorption of poorly soluble drug cyclosporin A (CsA), COCA was synthesized using choline and citronellic acid by one-step neutralization method, and then characterized by mass spectrometry, ¹H-NMR, and infrared spectrophotometry. Next, CsA-ionic liquid (CsA-COCA) was prepared by ultrasonic-assisted method and filled into enteric-coated capsules. After oral administration of CsA-COCA capsules or CsA suspension preparation in rats, CsA concentration in whole blood was assayed using liquid chromatography-tandem mass spectrometry (LC-MS/MS) method, and the pharmacokinetic parameters were calculated by DAS 2.0 software. All animal care and experiments followed the approval of Institutional Animal Care and Use Committee at Peking University Health Science Center. The results indicated that compared with oral administration of 10 mg·kg^-1 CsA suspension, the area under the curve (AUC), half-life time (T_1/2), and mean residence time (MRT) of CsA obtained by oral administration the same dose of CsA-COCA increased by 2.81, 4.41, and 1.77 times, respectively. The COCA prepared in this study can significantly promote the oral absorption of CsA in rats, and prolong the half-life. This study can provide reference for the study of oral formulation of insoluble drugs such as CsA.

Using Lonicera japonica genomic DNA as a template, we cloned Lonicera japonica U6 promoters. Four LjU6 promoters, 336, 708, 359 and 602 bp in length, were cloned by PCR from Lonicera japonica genomic DNA. PlantCARE analysis found that the four promoters contained typical promoter cis-elements, such as a TATA box and CAAT box, and contained regulatory elements related to light response and stress response. After the cloning products were sequenced, the LjU6 promoter was ligated to the pBI121 vector carrying the β-glucuronidase (GUS) gene to construct four LjU6-pBI121 fusion expression vectors. Nicotiana tabacum leaves were transformed by the Agrobacterium transient transformation method and GUS histochemical staining was performed on the leaves. The staining results showed that LjU61-F1 had the highest transcriptional activity. This study thus identified a U6 promoter with high transcriptional activity, providing a basis for the establishment of CRISPR/Cas9 genome editing technology in Lonicera japonica.

In order to explore the genetic diversity and structure of Bupleurum chinense, we used 18 pairs of SSR molecular markers to analyze the genetic diversity of 619 individuals in 62 cultivated and wild populations of Bupleurum chinense from Shanxi and the surrounding provinces. The results show that the 62 Bupleurum chinense populations have high genetic diversity, with that of the wild Bupleurum chinense populations greater than that of cultivated populations. AMOVA analysis indicated that genetic variation within populations was greater than between populations. Principal coordinate analysis (PCoA) divided the Bupleurum chinense populations into 3 groups, the first group containing wild Bupleurum chinense populations from all parts of Shanxi, the second group consisting of cultivated Bupleurum chinense populations from Shanxi, Hebei, Shaanxi and Liaoning, and the third group consisting of cultivated Bupleurum chinense from Shanxi and Gansu. STRUCTURE software cluster genetic structure analysis grouped the 62 Bupleurum chinense into two populations: the first group composition was the same as the population classified as the third category in the PCoA analysis, while the second group includes the populations from the first and second categories of the PCoA. PCoA, cluster genetic structure analysis, and NJ tree cluster all gather wild Bupleurum chinense population into a single category, distinguishing it from the cultivated populations. This study provides a theoretical basis for the utilization of germplasm resources, genetic variation and the development of quality germplasm resources for Bupleurum chinense.