{"id":8778,"date":"2024-04-12T16:52:21","date_gmt":"2024-04-12T14:52:21","guid":{"rendered":"https:\/\/www.em-grade.com\/non-categorizzato\/what-is-the-optimal-osmolality-of-a-fixative-solution\/"},"modified":"2024-12-12T16:08:34","modified_gmt":"2024-12-12T15:08:34","slug":"what-is-the-optimal-osmolality-of-a-fixative-solution","status":"publish","type":"post","link":"https:\/\/www.em-grade.com\/it\/non-categorizzato\/what-is-the-optimal-osmolality-of-a-fixative-solution\/","title":{"rendered":"What is the optimal osmolality of a fixative solution?"},"content":{"rendered":"<p><em><strong>optimal-osmolality of fixative solution<\/strong><\/em><\/p>\n<p>The total or final osmolality\u00a0 of fixative solution mixtures (buffer + fixative + optional additive) has an important effect on tissue morphology and cell organelle distribution.<\/p>\n<ul>\n<li>Hypertonic solutions cause cell shrinkage (water outflow).<\/li>\n<li>Isotonic fixatives produce slightly distorted cells and non-optimal fixation, as do hypotonic fixatives.<\/li>\n<\/ul>\n<p><strong>The best results were obtained with slightly hypertonic solutions (420 to 440 mOsm).<\/strong><\/p>\n<ul>\n<li style=\"text-align: left;\"><span style=\"color: #000000;\">The effects of the osmotic pressure that the fixation solution develops are even more visible at the ultrastructural level (E.M.) than at the histological level (O.M.) because the semi-permeable phospholipid membranes are easily weakened by solutions that are too hypotonic or hypertonic.<\/span><\/li>\n<li style=\"text-align: left;\"><span style=\"color: #000000;\">Normally the osmolarity is chosen according to its osmole value of the internal environment (blood serum for mammals ~320 mOsm, sea water for marine fish ~1000mOsm.).<\/span><\/li>\n<li style=\"text-align: left;\"><span style=\"color: #000000;\">By experience, microscopists set their osmolarity a little higher, respectively 390 to 430 mOsm, marine organisms 1100mOsm up to 1350mOsm.<\/span><\/li>\n<li><\/li>\n<li style=\"text-align: right;\"><span style=\"color: #ff6600;\"><strong><em>exemple fixation protocol (Mammifere)<\/em><\/strong><\/span><\/li>\n<li style=\"text-align: right;\"><span style=\"color: #0000ff;\">click images<\/span><\/li>\n<\/ul>\n<div id=\"attachment_8119\" style=\"width: 601px\" class=\"wp-caption alignnone\"><a href=\"https:\/\/www.em-grade.com\/wp-content\/uploads\/2024\/04\/exemple-calcul-osmolarite-fixation.jpg\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-8119\" class=\"wp-image-8119 size-full\" src=\"https:\/\/www.em-grade.com\/wp-content\/uploads\/2024\/04\/exemple-calcul-osmolarite-fixation.jpg\" alt=\"optimal-osmolality fixative solution on the board \" width=\"591\" height=\"475\" \/><\/a><p id=\"caption-attachment-8119\" class=\"wp-caption-text\">board of optimal-osmolality fixative solution<\/p><\/div>\n<p style=\"text-align: right;\"><a href=\"https:\/\/www.em-grade.com\/wp-content\/uploads\/2024\/04\/equilibre-dosmolarite-avec-membrane-semipermeable.jpg\">\u00a0 \u00a0 \u00a0 <\/a><\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>optimal-osmolality of fixative solution The total or final osmolality\u00a0 of fixative solution mixtures (buffer + fixative + optional additive) has an important effect on tissue morphology and cell organelle distribution&#8230;.<\/p>\n","protected":false},"author":8,"featured_media":8780,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_seopress_titles_title":"","_seopress_titles_desc":"","_seopress_robots_index":"","_seopress_robots_follow":"","_seopress_robots_imageindex":"","_seopress_robots_snippet":"","_seopress_robots_primary_cat":"","_seopress_robots_breadcrumbs":"","_seopress_robots_freeze_modified_date":"","_seopress_robots_custom_modified_date":"","_seopress_robots_canonical":"","_seopress_social_fb_title":"","_seopress_social_fb_desc":"","_seopress_social_fb_img":"","_seopress_social_fb_img_attachment_id":0,"_seopress_social_fb_img_width":0,"_seopress_social_fb_img_height":0,"_seopress_social_twitter_title":"","_seopress_social_twitter_desc":"","_seopress_social_twitter_img":"","_seopress_social_twitter_img_attachment_id":0,"_seopress_social_twitter_img_width":0,"_seopress_social_twitter_img_height":0,"_seopress_redirections_value":"","_seopress_redirections_enabled":"","_seopress_redirections_enabled_regex":"","_seopress_redirections_logged_status":"","_seopress_redirections_param":"","_seopress_redirections_type":0,"_seopress_analysis_target_kw":"","_seopress_news_disabled":"","_seopress_video_disabled":"","_seopress_video":[],"_seopress_pro_schemas_manual":[],"_seopress_pro_rich_snippets_disable_all":"","_seopress_pro_rich_snippets_disable":[],"_seopress_pro_schemas":[],"itsec_x_frame_options":"","footnotes":""},"categories":[784,778],"tags":[],"class_list":["post-8778","post","type-post","status-publish","format-standard","has-post-thumbnail","category-chemistry-definitions-it","category-non-categorizzato"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.em-grade.com\/it\/wp-json\/wp\/v2\/posts\/8778","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.em-grade.com\/it\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.em-grade.com\/it\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.em-grade.com\/it\/wp-json\/wp\/v2\/users\/8"}],"replies":[{"embeddable":true,"href":"https:\/\/www.em-grade.com\/it\/wp-json\/wp\/v2\/comments?post=8778"}],"version-history":[{"count":1,"href":"https:\/\/www.em-grade.com\/it\/wp-json\/wp\/v2\/posts\/8778\/revisions"}],"predecessor-version":[{"id":10836,"href":"https:\/\/www.em-grade.com\/it\/wp-json\/wp\/v2\/posts\/8778\/revisions\/10836"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.em-grade.com\/it\/wp-json\/wp\/v2\/media\/8780"}],"wp:attachment":[{"href":"https:\/\/www.em-grade.com\/it\/wp-json\/wp\/v2\/media?parent=8778"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.em-grade.com\/it\/wp-json\/wp\/v2\/categories?post=8778"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.em-grade.com\/it\/wp-json\/wp\/v2\/tags?post=8778"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}