[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"detail-sidebar-cat-1-en-105":3,"doc-seo-253980-105":53,"doc-detail-253980-en":126},{"code":4,"msg":5,"data":6},0,"success",[7,14,19,24,29,34,39,44,49],{"id":8,"doc_module":9,"doc_module_name":10,"category_name":11,"show_sort_weight":12,"slug":13},11,1,"Template","Presentations",90,"presentations",{"id":15,"doc_module":9,"doc_module_name":10,"category_name":16,"show_sort_weight":17,"slug":18},12,"Resumes",80,"resumes",{"id":20,"doc_module":9,"doc_module_name":10,"category_name":21,"show_sort_weight":22,"slug":23},14,"Invoices",70,"invoices",{"id":25,"doc_module":9,"doc_module_name":10,"category_name":26,"show_sort_weight":27,"slug":28},15,"Posters",60,"posters",{"id":30,"doc_module":9,"doc_module_name":10,"category_name":31,"show_sort_weight":32,"slug":33},16,"Social Media",50,"social-media",{"id":35,"doc_module":9,"doc_module_name":10,"category_name":36,"show_sort_weight":37,"slug":38},17,"Forms",40,"forms",{"id":40,"doc_module":9,"doc_module_name":10,"category_name":41,"show_sort_weight":42,"slug":43},18,"Letters",30,"letters",{"id":45,"doc_module":9,"doc_module_name":10,"category_name":46,"show_sort_weight":47,"slug":48},21,"Paper Templates",5,"papers-templates",{"id":50,"doc_module":9,"doc_module_name":10,"category_name":51,"show_sort_weight":4,"slug":52},158,"General","general-158",{"code":4,"msg":54,"data":55},"ok",{"site_id":56,"language":57,"slug":58,"title":59,"keywords":60,"description":61,"schema_data":62,"social_meta":119,"head_meta":121,"extra_data":123,"updated_unix":125},105,"en","forensic-toxicology-laboratory-ethanol-methanol-2-propanol-and-acetone-automated-head-space-analysis-principle","Forensic Toxicology Laboratory - Ethanol, Methanol, 2-Propanol and Acetone - Automated Head Space Analysis Principle","","The automated head space gas chromatography method determines ethanol, 2-propanol, methanol, and acetone concentrations in biological specimens such as blood, vitreous humor, urine, and tissue homogenates. The approach relies on Henry’s law to measure vapor in equilibrium with the sealed specimen, followed by injection into a gas chromatograph and flame ionization detection. Quantitation uses internal standard (n-propanol) calibration with least-squares equations and peak-area ratio analysis, while ammonium sulfate liberates volatiles from the sample matrix.",{"@graph":63,"@context":118},[64,80,101],{"@type":65,"itemListElement":66},"BreadcrumbList",[67,71,74,77],{"item":68,"name":69,"@type":70,"position":9},"https://docshare.wps.com","Home","ListItem",{"item":72,"name":10,"@type":70,"position":73},"https://docshare.wps.com/template/",2,{"item":75,"name":51,"@type":70,"position":76},"https://docshare.wps.com/template/general/",3,{"item":78,"name":59,"@type":70,"position":79},"https://docshare.wps.com/template/forensic-toxicology-laboratory-ethanol-methanol-2-propanol-and-acetone-automated-head-space-analysis-principle/253980/",4,{"url":78,"name":59,"@type":81,"image":82,"author":87,"headline":59,"publisher":90,"fileFormat":93,"inLanguage":57,"description":61,"dateModified":94,"datePublished":95,"encodingFormat":93,"isAccessibleForFree":96,"interactionStatistic":97},"DigitalDocument",{"url":83,"@type":84,"width":85,"height":86},"https://docshare.wps.com/thumbnails/forensic-toxicology-laboratory-ethanol-methanol-2-propanol-and-acetone-automated-head-space-analysis-principle/253980.png","ImageObject",442,249,{"name":88,"@type":89},"Stanley","Person",{"url":68,"name":91,"@type":92},"DocShare","Organization","application/pdf","2026-09-22","2026-09-13",true,{"@type":98,"interactionType":99,"userInteractionCount":79},"InteractionCounter",{"@type":100},"ViewAction",{"@type":102,"mainEntity":103},"FAQPage",[104,110,114],{"name":105,"@type":106,"acceptedAnswer":107},"Which compounds are measured in this automated head space analysis method?","Question",{"text":108,"@type":109},"The method measures ethanol, 2-propanol, methanol, and acetone in biological specimens including blood, vitreous humor, urine, and tissue homogenates.","Answer",{"name":111,"@type":106,"acceptedAnswer":112},"How does head space chromatography prepare samples for GC analysis?",{"text":113,"@type":109},"Sealed vials containing the specimen, internal standard, and septum are heated until equilibrium is reached, then a sample of the head space vapor is removed by an automated sampling device and injected into the gas chromatograph.",{"name":115,"@type":106,"acceptedAnswer":116},"What principle and detection approach are used for quantitation?",{"text":117,"@type":109},"Volatile measurement is based on Henry’s law, and detection uses a flame ionization detector where burned volatiles generate a current proportional to amount. Concentrations are quantified using computer processing with internal standard (n-propanol) and calibration derived from least-squares equations and peak-area ratios.","https://schema.org",{"og:url":78,"og:type":120,"og:title":59,"og:site_name":91,"og:description":61},"article",{"robots":122,"canonical":78},"index,follow",{"doc_id":124,"site_id":56},253980,1789272613,{"code":4,"msg":5,"data":127},{"doc_id":124,"user_id":128,"nickname":88,"user_avatar":129,"doc_module":9,"category_id":50,"category_name":51,"doc_title":59,"doc_description":61,"doc_content":130,"file_id":131,"file_url":132,"file_type":133,"file_size":134,"view_count":76,"is_deleted":4,"is_public":9,"is_downloadable":9,"audit_status":9,"page_count":135,"language":136,"language_code":57,"site_id":56,"html_lang":57,"table_of_contents":137,"faqs":138,"seo_title":139,"seo_description":61,"update_tm":125,"read_time":140},2336477405376,"https://ap-avatar.wpscdn.com/davatar_29158cc5080c5b710cf443261637dec0","FORENSIC TOXICOLOGY LABORATORY  \nOFFICE OF CHIEF MEDICAL EXAMINER  \nCITY OF NEW YORK  \nETHANOL, METHANOL, 2-PROPANOL AND ACETONE  \nby  \nAUTOMATED HEAD SPACE ANALYSIS  \nPRINCIPLE  \nThis method is a modification of the one that has been used forensically for the determination of ethanol and other volatiles since 1964 when Machata first published his paper using this method.  \nThis method determines the concentration of ethanol, 2-propanol, methanol and acetone in biological specimens such as blood, vitreous humor, and urine and tissue homogenates. Head space techniques are based on Henry’s law which states that the ratio of a dissolved substance in an aqueous solution is dependent on temperature, pressure, and concentration in the aqueous medium. Volatile substances may be measured by analyzing the vapor (head space) which is in equilibrium with a liquid specimen. Biological fluids or tissue homogenates areplaced into a vial with the appropriate internal standard and sealed with a septum. The vial is heated and allowed to stand until equilibrium is reached. A sample of the head space is removed from the sealed vial by an automated sampling device and injected into a gas chromatograph. Only volatile substances will reach the column, non-volatiles will remain in the sample. The volatiles are separated by the column and detected by a flame ionization detector, where hydrogen is introduced and volatiles are burned in an atmosphere of air. Burning organic matter in the flame releases electrons and negative ions which are collected on the anode, producing a change in electrical current proportional to the amount of burned material. The current is amplified, digitized and raw data collected on a computer. The data is processed by computer programs and can be displayed as a peak in a chromatogram. Components may be identified qualitatively by their retention time (length of time they are retained on the column) . Quantitation is performed by computer programs, using the height ratios of the chromatographic peaks of interest and an internal standard (n-propanol), calculated from a least-squares equation derived from the four calibrators. The compounds are identified by their relative retention times on both columns and their quantitative amounts are determined by the peakarea ratios compared to that of the standard curve generated that day. See a representative chromatogram, Figure 1, page 26.  \nAutomated head space gas chromatography employed in this laboratory uses a salting-out agent, ammonium sulfate, which is present in the diluents solution and is used to liberate volatiles from their matrix. The diluent solution also contains sodium dithionite to liberate the oxygen from the red blood cells.  \nSAFETY  \nThe handling of all samples, reagents, and equipment is performed within the established laboratory safety guidelines detailed in the safety manual.  \nREAGENTS AND MATERIALS  \nAll solutions are prepared at room temperature (20-30 °C) .  \n1. Ethanol (ethyl alcohol, C2 H5OH, fw 46 .0) Aldrich, 200 proof or equivalent  \n2. Methanol (methyl alcohol, CH3OH, fw 32 .04) Fisher Scientific, certified or equivalent  \n3. 2-Propanol (2-propanol, isopropyl alcohol, (CH3CHOHCH3 , fw 60.10) Fisher Scientific, certified or equivalent  \n4. Acetone (CH3COCH3) fw 58.08 Fisher Scientific, certified or equivalent  \n5. 1-Propanol (n-propanol) (C3 H7OH, fw 60 . 10) Fisher Scientific, certified or equivalent  \n6. Formaldehyde solution (CH2O) -37% W/W, fw 30.03.  \nFisher Scientific, certified or equivalent. NOTE: Contains 10-15% methanol.  \n7. Ammonium sulfate (fw 132. 14)  \nFisher Scientific, certified ACS grade or equivalent  \n8. Sodium hydrosulfite (Dithionite, Na2S2O4 , fw 174. 10) Fisher Scientific, certified ACS grade or equivalent  \n9. Deionized water  \n10. Certified negative calf brain  \nPreviously found to be volatile free. Store frozen. Discard after 3 months.  \n11. Hamilton Microlab 500 series pipettor-diluter  \n12. Vortex 2-genie, centrifuge ( m","cbCaicjdkAaOU75z","https://ap.wps.com/l/cbCaicjdkAaOU75z","pdf",634280,24,"English","# Automated Head Space Analysis Principle\n## Safety\n## Reagents and Materials\n## Preparation of Calibrators and Controls","[{\"question\":\"Which compounds are measured in this automated head space analysis method?\",\"answer\":\"The method measures ethanol, 2-propanol, methanol, and acetone in biological specimens including blood, vitreous humor, urine, and tissue homogenates.\"},{\"question\":\"How does head space chromatography prepare samples for GC analysis?\",\"answer\":\"Sealed vials containing the specimen, internal standard, and septum are heated until equilibrium is reached, then a sample of the head space vapor is removed by an automated sampling device and injected into the gas chromatograph.\"},{\"question\":\"What principle and detection approach are used for quantitation?\",\"answer\":\"Volatile measurement is based on Henry’s law, and detection uses a flame ionization detector where burned volatiles generate a current proportional to amount. Concentrations are quantified using computer processing with internal standard (n-propanol) and calibration derived from least-squares equations and peak-area ratios.\"}]","Forensic Toxicology Laboratory - Ethanol, Methanol, 2-Propanol and Acetone - Automated Head Space Analysis Principle | PDF",8]