{"82871":{"#nid":"82871","#data":{"type":"news","title":"\u0027Dog-on-a-Chip\u0027 Could Replace Drug-Sniffing Canines","body":[{"value":"\u003Cp\u003EPolice dogs across the country could soon be out of work, replaced by an electronic \u0022dog-on-a-chip\u0022 that sniffs out cocaine and other narcotics. Scientists at Georgia Tech have created a new detection tool that is portable, inexpensive, and doesn\u0027t require feeding or grooming. They say it is superior to previous \u0022electronic noses\u0022 designed for this purpose.\u003C\/p\u003E\n\u003Cp\u003EThe report will appear in the Nov. 15 edition of \u003Cem\u003EAnalytical Chemistry\u003C\/em\u003E, a peer-reviewed journal of the American Chemical Society, the world\u0027s largest scientific society.\n\u003C\/p\u003E\n\u003Cp\u003E\u0022Our technology provides a hand-held sensing device capable of real-time detection, reducing the time between drug seizure and laboratory analysis,\u0022 says Desmond Stubbs, a doctoral candidate in chemistry working under the direction of William Hunt, Ph.D., a professor in Georgia Tech\u0027s School of Electrical and Computer Engineering.\n\u003C\/p\u003E\n\u003Cp\u003EThe sensor, which performed well in the lab and in a field test with the Georgia Bureau of Investigation, is \u0022an elegant fusion of biotechnology and microelectronics,\u0022 according to Hunt. This combination of disciplines makes the sensor superior to previous \u0022electronic noses.\u0022 The U.S. government will spend more than $19 billion this year in the war on drugs, according to the Office of National Drug Policy. Police dogs are important tools in this battle; their highly developed olfactory systems can detect small molecules in the part-per-billion range.\n\u003C\/p\u003E\n\u003Cp\u003EBut using dogs has its drawbacks. They require expensive handlers to train and care for them, and the seized drugs must still be sent to the lab for further analysis - adding trained technicians and costly lab equipment to the tab.\n\u003C\/p\u003E\n\u003Cp\u003EPlus, scientists still don\u0027t know exactly what chemicals the dogs are sensing, allowing for significant variations from one dog to the next. Dogs also have trouble detecting specific drug targets in the presence of other odors, such as coffee grounds.\n\u003C\/p\u003E\n\u003Cp\u003E\u0022Unfortunately, the illicit drug traffickers are aware of this and invariably mask their product with different chemicals to evade authorities,\u0022 Stubbs says.\n\u003C\/p\u003E\n\u003Cp\u003EThe new device addresses all of these issues. Two key features of any vapor-sensing tool are sensitivity and specificity. Sensitivity is the ability to detect very small amounts of a chemical. Specificity is the ability to differentiate a certain chemical from a group of many similar ones (e.g., cocaine from coffee grounds).\n\u003C\/p\u003E\n\u003Cp\u003EThe dog-on-a-chip can sense cocaine at a few trillionths of a gram. This sensitivity is achieved through surface acoustic wave (SAW) electronics, a method of detecting a chemical by measuring the disturbance it causes in sound waves across a tiny quartz crystal. This is a fairly common analytical method, and it has been used in other electronic noses, but by itself it does not address the problem of specificity.\n\u003C\/p\u003E\n\u003Cp\u003EThe new chip goes a step further by incorporating monoclonal antibodies - cloned copies of proteins called antibodies that the immune system produces to fight foreign invaders. The researchers used anti-benzoylecgonine (anti-BZE) in the device because it differs only slightly in structure from cocaine, allowing it to bind preferentially to that molecule.\n\u003C\/p\u003E\n\u003Cp\u003EThe SAW sensor is coated with a thin layer of anti-BZE. When a vapor sample passes through, cocaine molecules attach to anti-BZE molecules, causing a disturbance in the sound waves on the quartz crystal that is detected as an electrical signal.\n\u003C\/p\u003E\n\u003Cp\u003E\u0022We are the first group to use specific antibodies to differentiate similar sized molecules in a complex vapor sample,\u0022 Hunt says. This gives the dog-on-a-chip an advantage over its canine competitors and other electronic devices. It will also be significantly cheaper and less time-consuming by removing many of the steps from the current detection protocol.\n\u003C\/p\u003E\n\u003Cp\u003EThe new device was carefully calibrated in a laboratory setting, and then it was put to the test in the field. \u0022In field tests conducted at the Georgia Bureau of Investigation, we were able to detect cocaine obtained during an actual drug seizure,\u0022 Stubbs says. \u0022By simply drawing the vapor through our prototype device, we got a positive detection in a matter of seconds.\u0022\n\u003C\/p\u003E\n\u003Cp\u003EThe ability to detect and identify small, non-volatile molecules like cocaine based on their electronic vapor signature could also be used in airports and other locations to detect explosives and chemical warfare agents, according to the researchers.\n\u003C\/p\u003E\n\u003Cp\u003EThe U.S. Customs Service and the Office of National Drug Control Policy (ONDCP) provided funding for this research.\n\u003C\/p\u003E\n\u003Cp\u003EA pdf file of the Nov. 15 report to appear in \u003Cem\u003EAnalytical Chemistry\u003C\/em\u003E is available by emailing Larry Bowie at \u003Ca href=\u0022mailto:larry.bowie@icpa.gatech.edu\u0022\u003Elarry.bowie@icpa.gatech.edu\u003C\/a\u003E\n\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"Police dogs across the country could soon be out of work, replaced by an electronic \u0022dog-on-a-chip\u0022 that sniffs out cocaine and other narcotics. Scientists at Georgia Tech have created a new detection tool that is portable, inexpensive, and doesn\u0027t require feeding or grooming. They say it is superior to previous \u0022electronic noses\u0022 designed for this purpose.","format":"limited_html"}],"field_summary_sentence":"","uid":"27304","created_gmt":"2003-11-07 01:00:00","changed_gmt":"2016-10-08 03:02:02","author":"Matthew Nagel","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2003-11-07T00:00:00-05:00","iso_date":"2003-11-07T00:00:00-05:00","tz":"America\/New_York"},"extras":[],"hg_media":{"82881":{"id":"82881","type":"image","title":"Bill Hunt and Desmond Stubbs","body":null,"created":"1449178087","gmt_created":"2015-12-03 21:28:07","changed":"1475894700","gmt_changed":"2016-10-08 02:45:00"},"82891":{"id":"82891","type":"image","title":"Desmond Stubbs","body":null,"created":"1449178087","gmt_created":"2015-12-03 21:28:07","changed":"1475894700","gmt_changed":"2016-10-08 02:45:00"}},"media_ids":["82881","82891"],"related_links":[{"url":"http:\/\/www.chemistry.gatech.edu\/","title":"School of Chemistry and Biochemistry"},{"url":"http:\/\/www.ece.gatech.edu\/","title":"School of Electrical and Computer Engineering"}],"groups":[{"id":"1214","name":"News Room"}],"categories":[],"keywords":[],"core_research_areas":[],"news_room_topics":[],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cstrong\u003ELisa Grovenstein\u003C\/strong\u003E\u003Cbr \/\u003ECommunications \u0026amp; Marketing\u003Cbr \/\u003E\u003Ca href=\u0022http:\/\/www.gatech.edu\/contact\/index.html?id=lgrovenste3\u0022\u003EContact Lisa Grovenstein\u003C\/a\u003E\u003Cbr \/\u003E\u003Cstrong\u003E404-894-8835\u003C\/strong\u003E","format":"limited_html"}],"email":["lisa.grovenstein@comm.gatech.edu"],"slides":[],"orientation":[],"userdata":""}}}