Objective:Explore the establishment of a fast, stable and sensitive high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method for detecting the level of m6A modification in RNA and its application.Methods:The degree of m6A in RNA can be expressed as the ratio of m6A and adenosine (A) in concentration, which can be determined by ESI source positive ion multiple reaction monitoring (MRM) mode. The established method was verified by analyzing three quality control samples (m6A: 4, 40, 400 nmol/L; A: 40, 400, 4 000 nmol/L) with three different concentrations of low, medium, and high. The method was used to detect the degree of m6A in RNA from mouse spleen T cells treated in different ways. The t test was used to compare the differences between the two groups of data. Results:The established method had a good Linearity ( R2>0.99) in a range of 1-500 nmol/L for m6A and 10-5 000 nmol/L for A. The limit of detection (LOD) was 1 nmol/L for m6A and 10 nmol/L for A. The recoveries were between 98.9% and 116.5%. The intra-day ( n=5) RSDs and the inter-day ( n=15, 5 days) RSDs were 2.4%-9.5% and 4.4%-9.6%, respectively. And this method was used to detect the degree of m6A in the RNA from mouse spleen T cells cultured in different conditions. The results showed that the m6A modification level in the RNA of primary CD8 +T cell was 0.271 5±0.017 9, and the m6A modification level in the RNA of primary CD8 +T cell with IL-27 was 0.251 7±0.015 0, indicating that primary CD8 +T cells have a higher level of RNA methylation. Conclusion:This research has established a fast, simplemethylation degree in RNA with HPLC-MS/MS. This method is easy to be popularized and is suitable for the detection of large quantity of samples, and of great significance in analyzing the relationship between methylation and diseases.

Objective:Explore the establishment of a fast, stable and sensitive high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method for detecting the level of m6A modification in RNA and its application.Methods:The degree of m6A in RNA can be expressed as the ratio of m6A and adenosine (A) in concentration, which can be determined by ESI source positive ion multiple reaction monitoring (MRM) mode. The established method was verified by analyzing three quality control samples (m6A: 4, 40, 400 nmol/L; A: 40, 400, 4 000 nmol/L) with three different concentrations of low, medium, and high. The method was used to detect the degree of m6A in RNA from mouse spleen T cells treated in different ways. The t test was used to compare the differences between the two groups of data. Results:The established method had a good Linearity ( R2>0.99) in a range of 1-500 nmol/L for m6A and 10-5 000 nmol/L for A. The limit of detection (LOD) was 1 nmol/L for m6A and 10 nmol/L for A. The recoveries were between 98.9% and 116.5%. The intra-day ( n=5) RSDs and the inter-day ( n=15, 5 days) RSDs were 2.4%-9.5% and 4.4%-9.6%, respectively. And this method was used to detect the degree of m6A in the RNA from mouse spleen T cells cultured in different conditions. The results showed that the m6A modification level in the RNA of primary CD8 +T cell was 0.271 5±0.017 9, and the m6A modification level in the RNA of primary CD8 +T cell with IL-27 was 0.251 7±0.015 0, indicating that primary CD8 +T cells have a higher level of RNA methylation. Conclusion:This research has established a fast, simplemethylation degree in RNA with HPLC-MS/MS. This method is easy to be popularized and is suitable for the detection of large quantity of samples, and of great significance in analyzing the relationship between methylation and diseases.

ObjectiveTo compare the effects of different processing methods in ancient and modern times on the chemical components of Lilii Bulbus decoction， and to provide experimental support for the origin processing， decoction piece processing and clinical application of this herb. MethodUltra high performance liquid chromatography tandem quadrupole electrostatic field orbitrap high resolution mass spectrometry（UHPLC-Q-Orbitrap HRMS） was used for structural identification of the compounds using excimer ions， secondary MS and characteristic fragment ions， and referring to relevant literature and database information. Principal component analysis（PCA） and orthogonal partial least squares discriminant analysis（OPLS-DA） were used to screen the main differential components， the differential components were quantitatively studied by high performance liquid chromatography（HPLC）， in order to compare the types and contents of chemical components in the decoction of different processing products of Lilii Bulbus. ResultA total of 24 chemical components were identified from the decoction of different processed products of Lilii Bulbus， water extract and scalding liquid of fresh Lilii Bulbus， including 17 phenols， 5 saponins and 2 alkaloids. Compared with the fresh Lilii Bulbus decoction， the contents of regaloside A， p-coumaric acid， colchicine and other components in the decoction of dry Lilii Bulbus processed by scalding method decreased， the content of regaloside C in the decoction of dry Lilii Bulbus processed by steaming method decreased， and the contents of regaloside A and regaloside C in the decoction of fresh Lilii Bulbus processed by water immersion also decreased. Compared with the decoction of dry Lilii Bulbus processed by scalding method， the overall content of components in the fresh Lilii Bulbus decoction and the decoction of fresh Lilii Bulbus processed by water immersion was higher， the contents of components in the decoction of dry Lilii Bulbus processed by steaming method was higher， except for the slightly lower content of regaloside C. ConclusionDifferent processing processes have a certain effect on the types and contents of chemical components in Lilii Bulbus decoction. Scalding process is beneficial to the preservation of Lilii Bulbus， but can cause the loss of effective components. Compared with scalding method， steaming method can prevent browning of Lilii Bulbus and reduce the loss of its active ingredients. The processing method of removing foam after overnight immersion proposed by ZHANG Zhongjing may be more conducive to the treatment of Baihe disease， which can provide reference for the clinical rational application and mechanism research of different processed products of Lilii Bulbus.