正文描述：《透射电子显微镜样品制备技术（preparation technique of sample for transmission electron microscope）》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。
1、透射电子显微镜样品制备技术（Preparationtechniqueofsamplefortransmissionelectronmicroscope）PreparationtechniqueofsamplefortransmissionelectronmicroscopeThebasicrequirementsareasfollows:keepthematerialstructureandcertainchemicalcompositionaspossibleaspossible;andthethicknessofthematerialshouldnotexceed100
2、0.Tissuesandcellsmustbemadeintothinslicestoobtainbetterresolutionandsufficientcontrast;usingavarietyofmeans,suchaselectronicstaining,projection,etc.toimprovethebiologicalsamplesbynegativestainingelectronscatteringability,inordertoobtainbetterimagecontrast.Themethodofsamplepreparationvaries
3、accordingtothetypeofbiomaterialandthepurposeofthestudy.Onbiologicaltissuesandcells,usuallywithultramicrotomy,thelargesizematerialsappropriatetothesizeoftheultrathinsection,andtheuseofelectronicstaining,andimmunocytochemicallabelingandautoradiographymethodshowedvariousultrastructure,various
4、chemicalsandchangeparts.Forbiologicalmacromolecules(proteins,nucleicacids),bacteria,virusesandisolatedorganelles,granularmaterials,suchasprojectionandnegativestaining,areusedtoimprovethecontrastandshowthemorphologyandfinestructureofparticles.Inaddition,therearefreezingfracturesbasedonfreez
5、efixation-freezeetching,freezereplacement,freezedryingandothertechnologies.Ultrathinsectioninginvolvessmallpiecesofbiologicalmaterialsoakedandembeddedwithliquidresinmonomersandsolidifiedintoplasticblocks.Theyarethencutintoultrathinsectionsof500orabout50byamicrotome.Theproceduresforpreparin
6、gultrathinsectionsaresimilartothoseoflightmicroscopy,buttherequirementsofeachstep,andthereagentsandmethodsusedareverydifferent.Thechoiceofappropriatephysicalorchemicalmethodstokilltissueandcellsrapidly,tomaintainthenormalstructureoftissuesandcells,andtominimizethechangesinvarioussubstances
7、.Immobilizationenhancestheabilityofcellstoundergoencapsulation,sectioning,staining,andelectronbeambombardment.Themainfixationmethodsare:Fastfreezing,withrefrigerant(suchasliquidnitrogen,liquidFreon,liquidpropane)orothermethodtomakethebiologicalmaterialsrapidly
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