Direct Mass Spectrometric Analysis Of Chicken Joints And The Relationship Between Lipids And Bone Microstructure

There are many kinds of human bone and joint diseases,among which osteoporosis and osteoarthritis are common.By 2021,the number of osteoarthritis patients in the world has reached 355 million,and the number of domestic patients has reached 150 million,accounting for 43% of the global number of osteoarthritis patients,exceeding 10% of the total number of domestic patients[1].This has had an important impact on patients,families and society,resulting in a significant increase in the disability rate and the global main medical care costs.The pathological changes of joints involve many aspects,including the changes of synovium,cartilage,joints and bone microstructure.In most studies,joint morphological changes are evaluated by imaging,such as X-ray,micro computed tomography(CT),magnetic resonance imaging(MRI)and so on.In the detection of material changes,the traditional detection methods of joints mainly include chromatography,chromatography combined with mass spectrometry and nuclear magnetic resonance spectroscopy(NMR),and etc.These methods require multi-step sample pretreatment,such as drying,grinding,extraction,derivatization,separation and enrichment,etc.,which are complicated and cannot perform high-throughput and rapid analysis of complex matrix samples.In recent years,in addition to simple operation and fast analysis speed,ambient mass spectrometry has been widely used and developed in various fields because of its high sensitivity,high accuracy and low sample consumption.This technology can realize real-time,continuous and online direct mass spectrometry analysis of complex matrix samples without pretreatment of samples [2,3,4].In this paper,the physiological function of bone,the occurrence and development of related diseases,and traditional detection methods were briefly outlined first,and then several common ambient mass spectrometry techniques and their applications were introduced,including the principles and applications of sequential ionization mass spectrometry technology.On this basis,the main contents and research significance of this paper are as follows:1.A sequential ionization direct mass spectrometry device was developed.The structure and technical characteristics of the device were studied.The device has the advantages of small sample consumption,convenient installation and simple operation.2.The sequential ionization direct mass spectrometry technique was applied to the analysis of cancellous bone in chicken joints,and the lipids in cancellous bone were detected by direct mass spectrometry.The specific method was to place the cancellous bone on the organic filter membrane connected to the syringe needle,and the lower part of the syringe needle was connected to the traditional ESI ion source through a quartz capillary.Methanol containing 5% formic acid was selected as the extractant to perform direct mass spectrometry analysis(such as lipids)of cancellous in positive ion mode.Without the need of off-line extraction,enrichment,derivatization and other sample purification processes,sequential ionization direct mass spectrometry can accurately and quickly record the characteristic fingerprint of cancellous.The experimental results show that the sequential ionization direct mass spectrometry can quickly analyze the lipids in cancellous and explore the differences of lipid content under different extraction times at the molecular level.It has the characteristics of no sample pretreatment,low sample consumption and high sensitivity.3.The microscopic characterization of the cancellous bone was also performed to obtain the bone microstructural changes of the cancellous bone in different time periods.By combining mass spectrometry and microscopy,the molecular information,abundance content and morphological and structural changes of different components in cancellous bone can be obtained,providing a new analysis method for multidimensional analysis of cancellous bone.In this paper,by observing the changes of lipid and bone microstructure in cancellous bone,the result shows that there is a close relationship between lipid and bone microstructure.Therefore,it can help guide medication in clinical practice,so that patients can supplement certain lipids in time to prevent symptoms from worsening.