Novel Ionizable Lipid Nanoparticles for SARS-CoV-2 Omicron mRNA Delivery.

mRNA-based therapy has emerged as the most promising nucleic acid therapy in the fight against COVID-19. However, a safe and efficacious systemic delivery remains a challenge for mRNA therapy. Lipid nanoparticles (LNPs) are currently widely used in mRNA delivery vehicles. Here, a series of ionizable LNPs is rationally designed. YK009-LNP is an optimal delivery platform to carry mRNA. YK009-LNP exhibits higher mRNA delivery efficiency, a more favorable biodistribution pattern, and better safety than the approved MC3-LNP. In addition, mRNA encoding severe acute respiratory syndrome coronavirus 2 Omicron receptor binding domain protein is synthesized and intramuscular administration of mice with YK009-LNP-Omicron mRNA induces a robust immune response and immune protective effect. A novel mRNA delivery vehicle with more powerful delivery efficiency and better safety than the approved LNPs is provided here.

A high-throughput metabolomics approach for the comprehensive differentiation of four Pulsatilla Adans herbs combined with a nontargeted bidirectional screen for rapid identification of triterpenoid saponins.

Pulsatilla Adans (PSA) herbs (Ranunculaceae) have been widely used in traditional medicine in China and other countries. However, the authentication and quality control of PSA herbs have always been a challenging task due to their similar morphological characteristics and the diversity of the multiple components that exist in the complicated matrix. Herein, a novel integrated strategy combining UHPLC/Q-Orbitrap-MS techniques with chemometrics analysis is proposed for the discrimination of PSA materials. We developed a comprehensive method integrating a nontargeted bidirectionally screened (NTBDS) MS data set and a targeted extraction peak area analysis for the characterization of triterpenoid saponins of PSA from different species. After that, partial least-squares discriminant analysis (PLS-DA) was performed on the obtained MS data set and the parameter variable importance for the projection (VIP) value and P value were employed to screen the valuable MS features to discriminate PSA from different species. In addition, the receiver operating characteristic (ROC) curve is used to verify the reliability of MS features. Finally, heatmap visualization was employed to clarify the distribution of the identified triterpenoid saponins, and four medicinal species of PSA were successfully differentiated. Additionally, 34 constituents were reported in PSAs for the first time, 81 triterpenoid saponins were identified as differential components, and 12 chemical ingredients were characterized as potential chemical markers to differentiate the four officinal PSA herbs. This is the first time that the differences in different PSA herbs have been observed systematically at the chemical level. The results suggested that using the identified characteristic components as chemical markers to identify different PSA herbs was effective and viable. This method provides promising perspectives in the analysis and identification of the ingredients of Chinese herbal medicines, and the identification of similar herbs from the same species.

Simultaneous Determination of Six Coumarins in Rat Plasma and Metabolites Identification of Bergapten in Vitro and in Vivo.

Coumarins are abundant in Umbelliferae and Rutaceae plants possessing varied pharmacological activities. The objectives of this study are to develop and validate the method for determination of six coumarins in rat plasma by liquid chromatography coupled with tandem mass spectrometry (LC-MS) and identify the metabolites of bergapten by ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS), respectively. Data-dependent acquisition mode (DDA) was applied to trigger enhanced product ion (EPI) scans by analyzing multiple reaction monitoring (MRM) signals. An efficient data processing method "key product ions (KPIs)" was used for rapid detection and identification of metabolites as an assistant tool. The time to reach the maximum plasma concentration ( Tmax) for the six compounds ranged from 1 to 6 h. A total of 24 metabolites of bergapten were detected in vitro and in vivo. The results could provide a basis for absorption and metabolism of coumarins.

Discrimination and Chemical Phylogenetic Study of Four Pulsatilla Herbs Using UPLC-ESI-MS/MS Combined with Hierarchical Cluster Analysis.

A tissue-smashing based ultra-rapid extraction coupled with ultra-performance liquid chromatography tandem-mass spectrometry (UPLC-MS/MS) method was developed to determine 10 major triterpenoid saponins from Pulsatilla herbs. Compound 4 was characterized as betulinic acid glycoside 3-O-α-arabinopyranosyl-28-O-ß-glucopyranosyl-23-hydroxy with HR-ESI-MS, 1H-NMR and 13C-NMR experiment. The MS spectra result showed that the ionization of compound 4 was more efficient in the positive mode. Meanwhile, the ions at m/z 789.6 and m/z 627.5 were selected as precursor and product ion for the determination, respectively. The chromatographic separation was carried out on a Phenomenex Kinetex C18 column using a gradient mobile phase system composed of 0.1% formic acid both in methanol and water at a flow rate of 0.4 mL/min. The detection was performed by multiple reaction monitoring mode, using electrospray ionization in the positive and negative mode. The total run time was 6 min. The calibration curves possessed good linearity with all coefficients higher than 0.9987. The intra- and interday precisions were no more than 4.9%, and the average recoveries were from 97.6% to 103.4% with RSD <4.7%. Moreover, hierarchical cluster analysis was performed to compare and discriminate the Pulsatilla herbs based on the quantitative data. The hierarchical cluster analysis results demonstrated that Pulsatilla chinensis, Pulsatilla cernua, Pulsatilla dahurica, Pulsatilla turczainovii samples could be easily discriminated from each other based on the contents of triterpenoid saponins and the established method is feasible for quality control of Pulsatilla herbs.

UPLC-QTOF-MS/MS based screening and identification of the metabolites in rat bile after oral administration of imperatorin.

The detection of drug metabolites, particularly for minor metabolites, continues to be a challenge owing to the complexity of biological samples. Imperatorin is an active natural furocoumarin ingredient originating from many traditional Chinese herbal medicines. In the present study, the metabolites of imperatorin after oral administration were qualitatively investigated, and possible metabolic pathways of it were subsequently proposed. Bile samples were collected after oral administration and pretreated by the application of Waters Ostro. The QTOF-MS/MS data was acquired using ultra high performance liquid chromatography coupled to quadrupole time flight spectrometry (UPLC-QTOF-MS). Based on this analytical strategy, 32 metabolites (23 phase I and 9 phase II metabolites) were identified in rat bile. The results demonstrated that C5H8 could be easily eliminated from imperatorin forming the metabolite M1. It also indicated that imperatorin and M1 underwent extensive metabolic reactions including oxidation, hydrolysis, methylation, glucuronide conjugation, C2H5NO2S conjugation and C3H5NO2S conjugation. This is the first study of imperatorin metabolism in bile samples. The proposed metabolic pathways in this research will provide essential data for further pharmaceutical studies of other linear-type furocoumarins.

[Simultaneous quantification of 7 coumarins in common cnidium fruit by GC-MS].

A GC-MS-SIM method was developed for the simultaneous determination of the 7 coumarins in common cnidium fruit. The 7 bioactive constituents were separated on DB-1 capillary column（30 m × 0.25 mm, 0.25 µm） using temperature programming. The interface temperature was set at 280 ℃; Ion source temperature: 250 ℃; Quadrupole temperature: 150 ℃; EI mode: 70 e V; The mass spectrometer detector was in SIM mode; Scan range: 50-350 amu. All the 7 marker substances showed good linearity（r(2) > 0.998 6） in the test ranges. The LODs and LOQs for the compounds ranged from 1.06 to 10.11 ng·mL(-1) and from 3.21 to 29.88 ng·m L(-1), respectively. The overall intra-day（n = 6） and inter-day（n = 3） RSDs were 0.7%-2.5% and 1.2%-3.3%, respectively. The overall recoveries were between 92.38% and 100.50% for all compounds. This method was simple, rapid, sensitive, with good specificity, and it can provide a reference for the quality control of common cnidium fruit.

[Determination of 14 components in Bazibushen capsule by UPLC-ESI-MS/MS].

The study developed a method for the determination of 14 components in Bazibushen capsule by UPLC-ESI-MS/MS. Waters ACQUITY BEH C(18) column (50 mm × 2.1 mm,1.7 µm) was used and the column temperature was 40 ℃.A linear gradient elution of eluents A (acetonitrile) and B（0.1% acetic acid） was used for the separation. The source temperature was set at 150 ℃.The capillary voltage was set at 2.0 k V. The source offset voltage was kept at 50 V. The desolvation temperature was set at 500 ℃.The desolvation flow was 800 L·h(-1).The cone flow was 150 L·h(-1). The nebuliser pressure was 7.0 Bar . Multiple reaction monitoring mode (MRM) is adopted. All of the 14 components showed good linearity (r2 > 0.999 1) in the test ranges. The LOQs for the compounds ranged from 0.11-4.52 ng·m L(-1), respectively.The RSDs were 0.8%-2.1%.The overall recoveries were between 97.89% and 101.9% for all compounds. The method is simple, rapid, accurate and highly reproducible, and may be used in the determination of 14 components in Bazibushen capsule.

Simultaneous quantification of 16 bioactive constituents in Common cnidium fruit by liquid chromatography-electrospray ionization-mass spectrometry.

A novel quantitative method using high-performance liquid chromatography coupled to electrospray ionization tandem mass spectrometry was developed for simultaneous determination of the 16 important bioactive constituents including nine coumarins, and seven flavonoids in Common cnidium fruit samples from different regions. The separation was performed on a C18 column with linear gradient elution of acetonitrile and 0.1% acetic acid at a flow rate of 1.0 ml/min in 15 min. Quantification of the analytes was achieved by use of a hybrid quadrupole linear ion-trap mass spectrometer. Multiple-reaction monitoring scanning was employed with switching electrospray ion source polarity between positive and negative modes in a single run. The validation results of the method indicated that the method was simple, rapid, specific, and reliable. The results demonstrated that the quantitative difference in content of 16 bioactive constituents was useful not only for chemotaxonomy of many samples from different sources but also for the standardization and differentiation of many similar samples. Simultaneous quantification of bioactive components by high performance liquid chromatography-tandem mass spectrometric method would be a well acceptable strategy to comprehensively control the quality of C. cnidium fruit.

[Rapid identification 15 effective components of anti common cold medicine with MRM by LC-MS/MS].

This paper reports the establishment of a method for rapid identification 15 effective components of anti common cold medicine (paracetamol, aminophenazone, pseudoephedrine hydrochloride, methylephedrine hydrochloride, caffeine, amantadine hydrochloride, phenazone, guaifenesin, chlorphenamine maleate, dextromethorphen hydrobromide, diphenhydramine hydrochloride, promethazine hydrochloride, propyphenazone, benorilate and diclofenac sodium) with MRM by LC-MS/MS. The samples were extracted by methanol and were separated from a Altantis T3 column within 15 min with a gradient of acetonitrile-ammonium acetate (containing 0.25% glacial acetic acid), a tandem quadrupole mass spectrometer equipped with electrospray ionization source (ESI) was used in positive ion mode, and multiple reaction monitoring (MRM) was performed for qualitative analysis of these compounds. The minimum detectable quantity were 0.33-2.5 microg x kg(-1) of the 15 compounds. The method is simple, accurate and with good reproducibility for rapid identification many components in the same chromatographic condition, and provides a reference for qualitative analysis illegally added chemicals in anti common cold medicine.