Design And Implementation Of In Situ Fixed Preservation Device For Deep-sea Biological Samples

In the past few decades,with the rapid development of deep-sea sampling tools,it has become practical to obtain biological samples from deep-sea environments.Many studies have studied the diversity and ecological characteristics of deep-sea organisms through genome,transcriptome,proteome sequencing and analysis.Most of these studies are based on deep-sea samples obtained by conventional deep-sea sampling methods,which means that samples are retrieved from the seabed and chemically immobilized on research vessels,without effective protective treatment of biological samples.When organisms are transported from the sea floor to the sea surface,due to the change of ambient conditions such as temperature and pressure,various biological research parameters and indicators will change greatly.The retrieved samples lack credibility,and the quality of the captured deep-sea biological samples cannot be well guaranteed.It can be seen that the biological samples obtained by conventional sampling devices can hardly reflect the natural physiological and biochemical state when they inhabit the deep sea.Aiming at the preservation problem of deep-sea biological samples,an in situ fixed preservation device for deep-sea biological samples was designed in this thesis.The main task of the device is to capture organisms in the deep sea at the same time,in situ use of appropriate nucleic acid protectants to the captured organisms for a high percentage of chemical fixation,to obtain the deep-sea biological samples after in-situ fixation in real environment,effectively solve the problem of genetic material m RNA preservation at the stage from the collection of deep-sea biological samples to the laboratory.This thesis will introduce the main work contents in detail in the following parts.Firstly,this thesis introduces the background and significance of the design of deep-sea biological samples in situ fixed preservation device,points out the lack of reliability of biological samples obtained by conventional sampling device,and puts forward the main research content and structure arrangement of this paper.Secondly,according to the design requirements of the saver,the overall scheme is designed,and the overall system framework of the saver is constructed.According to the different functional characteristics of the system,the device is mainly divided into two modules,sample storage module and water pressure drive module.Then the core design of the device is summarized: biological sample chamber design and multi-channel hydraulic flow channel design based on the principle of Tesla valve.A high proportion of fixed biological samples can be obtained through the study of liquid injection mixing in the biological sample chamber.Through the design of protective liquid storage tank,biological sample tank structure,liquid injection pipeline design,locking pin mechanism design,hatchcover design,cover closing mechanism design,flow loss analysis,deep-sea magnetic pump selection and equipment power supply design,the deep-sea magnetic pump uses multi-channel drive flow to perform different operations.The whole system was assembled and integrated as a prototype.The prototype was tested through the static pressure experiment of magnetic pump and the pool experiment of the whole machine to verify the rationality of the design.Finally,the work content and innovation of this thesis are summarized,and the next research direction is prospected.