이 작품은 국립 자연 과학 재단의 중국 (No. 91543117)에 의해 재정적으로 지원 되었습니다.

주의: 사용 하기 전에 모든 관련 물질 안전 데이터 시트 (MSDS)를 참조 하십시오. 사용 하십시오 적절 한 개인 보호 장비, 예를 들면, 실험실 외 투, 장갑, 고글, 전체 길이 바지와 폐쇄 발가락 신발).
1. 초-nanoESI 소스를 설정
<ol><li>SESI 과정, 즉에 따르면 Sec nanoESI 소스를 설정 호흡 가스는 분무 깃털 교차 고 충전된 물방울 (그림 1)에 의해 이온화. 개별 실험실에 내장 된 소스 사용 하는 질량 분석기24,25인터페이스에 따라 다릅니다. 여기, 상용 nanoESI 소스 (그림 2)에 따라 Sec nanoESI 소스를 설정 하 고 벤치탑 4 중 극 orbitrap 질량 분석기를 구현 합니다. 참고: 소스의 본체는 입방 스테인레스 스틸 챔버 (길이 25 m m, 아이디 13 m m) (그림 2b) 챔버로 nanoESI 모 세관을 소개 하는 입구 (아이디 4 m m)와 함께. 따라서, 챔버 하지 않습니다 완전히 봉인 (그림 2b).</li>
	<li>가스 배달에 대 한 챔버의 각 측면에 두 개의 스테인레스 스틸 튜브 (길이 8 m m, 마약 5 m m, 아이디 3 m m)를 설치 합니다.</li>
	<li>NanoESI 모 세관의 눈 또는 디지털 현미경 nanoESI 스프레이 팁의 위치를 확인 하는 챔버의 위아래에 두 석 영 창 (아이디 14 m m)를 장비.</li>
	<li>질량 분석기의 스윕 콘 챔버 용접. 참고: 디자인 개별 실험실에서 사용 하는 질량 분석기의 대기압 인터페이스의 특정 형상에 따라 변경할 수 있습니다.</li>
</ol>2. 악기 최적화
<ol><li>제조업체의 지침에 따라 모두 긍정적이 고 부정적인 이온 검출 모드에서 질량 분 서 계를 보정. 보정을 적용 하 여 렌즈 잠재력 검색 조건과 같은 질량 분석기 매개 변수를 지정 된 해상도 값에 좋은 감도 및 피크 모양에 게 최적화 되어 있다. 70000의 대량 해상도 여기에 사용 됩니다.<ol>
<li>상업적인 ESI 소스;를 사용 하 여 완전 한 Q Exactive 교정 수행 그러나, 사용자 지정을 포함 하 여 모든 호환 소스와 질량 보정을 수행할 수 있습니다.</li>
	</ol>
</li>
	<li>이온 이동 관 (ITT) 질량 분석기 > 100 ° c의 온도 설정 350 ° C에서 최고 온도 설정할 수 있습니다, 하지만 그것은 몇 가지 화합물의 분해 될 수 있습니다. 따라서, 150 ° C이이 실험에 사용 됩니다. 참고: ITT 대신 샘플링 구멍을 특징으로 하는 질량 분석기에 대 한 샘플링 구멍의 온도 설정 > 100 ° c.</li>
	<li>ESI 용 매 및 흐름 속도 대 한 용 매 (예를 들어, 극성 및 변동)과 대상된 화합물 (예를 들어, 양성자 선호도)의 속성에 근거 하 여 적절 한 ESI 용 매를 선택 합니다. 물과 다양 한 비율에서 메탄올의 혼합물은 ESI 용 매25으로 일반적으로 사용 되었습니다. 이 실험에서는 물이 용 매13,,1923보고 위한 높은 이온화 효율은 0.1% (v/v) 포 름 산을 포함 하. ESI 용 매 유량 0-1.5의 범위에서 설정 μ/min와 200 nL/분. 참고: 드가 ESI 사용 하기 전에 30 분 용 매.</li>
	<li>초-nanoESI 소스 매개 변수, 주로 nanoESI 전압 및 nanoESI 모 세관 팁 위치를 최적화 합니다. 전압 일반적으로 범위는 2.0에서 4.5 kV. 여기 사용 2.5 kV입니다. 참고: ESI 전압 높은 흐름 속도 증가으로 적용 됩니다. 팁과 질량 분석기 구멍 사이의 거리는 5 m m 1에서 조정할 수 있습니다. 최적화, 후 질량 스펙트럼에서 관찰 된 정규화 된 강도 수준 (NL) > 1 x 10 해야6 및 총 이온 크로마 (TIC)의 유사 모두 긍정적이 고 부정적인 이온 검출 모드에서 < 10% 이어야 한다. 질량 스펙트럼 및 TIC m/z 50-750의 질량 범위에서 얻을 수 있습니다.</li>
	<li>가스 소스에 적용 됩니다. 이 실내 공기에서 VOCs의 영향을 줄이는 목표로 단계는 선택적입니다. 고 순도 질소 가스 (N2, 99.99%) 또는 순수한 공기를 사용할 수 있습니다. 순수 가스의 존재와 질량 스펙트럼에서 관찰 하는 NL > 1 x 10 해야5 와 TIC의 변화 모두 긍정적이 고 부정적인 이온 검출 모드에서 < 10% 이어야 한다. 고 순도 N2 는 여기에 사용 되 고 0.8 L/분 전달. 참고: 순수한 가스와 호흡 가스의 총 유량 질량 분석기의 구멍을 통해 유량 보다 높아야 한다.</li>
</ol>3입니다. exhaled 호흡의 측정
<ol><li>실내 공기를 흡입 하 고 일정 한 유량에서 폐의 모든 공기를 밖으로 호흡 하는 정상적인 증발 기를 수행 합니다. 증발 기 유량을 압력 계 또는 유량 주제를 볼 수를 모니터링 합니다. 테 프 론 (PTFE) 튜브를 사용 하 여 호흡 가스23제공.<ol>
<li>튜브 안에 수증기의 응축을 방지 하기 위해, 80-100 oC7,,2327 의 온도에 튜브가 열 하거나29Nafion 드라이어28,사용 합니다. 이 실험에서 주제 exhaled 0.4 L/분의 유량 계에 의해 제어.</li>
		<li>PTFE 튜브 (길이 13 ㎝, 아이디 4 m m)에 exhaled 호흡에서 수증기를 제거 하 고 흐름 미터의 콘센트를 연결 하는 Nafion 튜브 (길이 60 cm)를 유량의 입구를 연결 합니다. 그것은 하나의 증발 기 측정에 대 한 < 30 s를 걸립니다.</li>
		<li>4-6 복제 측정28,29를 수행 합니다.</li>
		<li>혼란 효과 최소화 하기 위해 참가자 들이 먹고, 마시고, 그리고 측정23전에 그들의 이빨 적어도 30 분을 솔 질에서 있다. 참고: 실내 공기에서 VOCs의 영향을 최소화 하기 위해 실내 공기26대신 가스를 흡입 보고 되었습니다 그것은. Nafion 튜빙을 사용 하는 경우 일부 극 지 화합물 손실 될 수 있습니다.</li>
		<li>측정, 동안 이온 강도 여부는 악기의 선형 검출 한계를 초과 하는 경우 확인 하십시오. 채도 신호의 샘플에서 화합물에서 실질적으로 발생 하지 않는 한 유물 피크 발생할 수 있습니다. 코를 통해 흡입, 주변 Voc 및 입자의 일부 제거 될 것 이다; 그러나, 그것은 주목할 만한 비 강에 화합물도 검색 될 수 있습니다.</li>
	</ol>
</li>
</ol>4. 구하는 호흡 지문 및 화합물의 시간 추적
<ol><li>Chromatograms 및 질량 스펙트럼을 얻을. 소프트웨어 (예: Xcalibur) 기록 chromatograms 및 질량 스펙트럼을 사용 합니다. 때문에 이것이 직접 MS 분석 크로마 분리를 수행, 총 이온 크로마 (TIC) 실제로 질량 스펙트럼에서 검색 된 모든 신호의 시간 추적을 나타냅니다 추출된 이온 크로마 (EIC) 표시의 시간 추적 한 지정 된 화합물입니다. 참고: 다른 상업 질량 분석기에 대 한 chromatograms 및 질량 스펙트럼 얻어질 수 있다 해당 데이터 수집 소프트웨어에 의해.</li>
	<li>Exhaled 호흡 지문 exhaled 호흡 측정 때 TIC의 다양 한 검사를 선택 하 여 얻을. 이러한 검사의 평균을 대표 하는 소프트웨어에 의해 질량 스펙트럼을 얻을.<ol>
<li>호흡 지문에서 배경 봉우리를 제거 하려면 배경 빼기 도구를 사용 하 여 소프트웨어에. 제조업체에서 제공한 설명서를 참조 하십시오. 간단 하 게, 아니 숨 샘플 도입 되어 검사의 동일한 수를 선택 하 고 빼기 호흡 지문에서 배경 질량 스펙트럼. 참고:이 방법에서는, 호흡 지문에 기능을 식별 하기 위해 임계값 세 번 배경 신호의 표준 편차로 정의 됩니다. 다른 상업 질량 분석기에 대 한 해당 데이터 수집 소프트웨어에 의해 배경 빼기를 수행할 수 있습니다.</li>
	</ol>
</li>
	<li>지정 된 화합물의 시간 추적을 가져옵니다. 호흡 지문에 대상된 화합물의 피크를 선택 하 고 화합물의 시간 추적 소프트웨어에 의해 연속적으로 취득 된다.</li>
</ol>

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Breath Res. 5 (1), 016002-016012 (2011).</li><li>Mart&#237;nez-Lozano Sinues, P., Zenobi, R., Kohler, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Analysis+of+the+exhalome+a+diagnostic+tool+of+the+future.">Analysis of the exhalome a diagnostic tool of the future.</a> Chest. 144 (3), 746-749 (2013).</li><li>Mart&#237;nez-Lozano Sinues, P., Fernandez de la Mora, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Direct+analysis+of+fatty+acid+vapors+in+breath+by+electrospray+ionization+and+atmospheric+pressure+Ionization-Mass+Spectrometry.">Direct analysis of fatty acid vapors in breath by electrospray ionization and atmospheric pressure Ionization-Mass Spectrometry.</a> Anal. Chem. 80 (21), 8210-8215 (2008).</li><li>Mart&#237;nez-Lozano Sinues, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Breath+analysis+in+real+time+by+mass+spectrometry+in+chronic+obstructive+pulmonary+disease.">Breath analysis in real time by mass spectrometry in chronic obstructive pulmonary disease.</a> Respiration. 87 (4), 301-310 (2014).</li><li>Mart&#237;nez-Lozano Sinues, P., Kohler, M., Zenobi, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Monitoring+diurnal+changes+in+exhaled+human+breath.">Monitoring diurnal changes in exhaled human breath.</a> Anal. Chem. 85 (1), 369-373 (2013).</li><li>Chen, H. W., Zenobi, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neutral+desorption+sampling+of+biological+surfaces+for+rapid+chemical+characterization+by+extractive+electropray+ionization+mass+spectrometry.">Neutral desorption sampling of biological surfaces for rapid chemical characterization by extractive electropray ionization mass spectrometry.</a> Nat. Protoc. 3 (9), 1467-1475 (2008).</li><li>Li, X., Hu, B., Ding, J., Chen, H. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rapid+characterization+of+complex+viscous+samples+at+molecular+levels+by+neutral+desorption+extractive+electrospray+ionization+mass+spectrometry.">Rapid characterization of complex viscous samples at molecular levels by neutral desorption extractive electrospray ionization mass spectrometry.</a> Nat. Protoc. 7 (6), 1010-1025 (2011).</li><li>Gordon, S. M., Szidon, J. P., Krotoszynski, B. K., Gibbons, R. D., O'Neill, H. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Volatile+organic+compounds+in+exhaled+air+from+patients+with+lung+cancer.">Volatile organic compounds in exhaled air from patients with lung cancer.</a> Clin. Chem. 31 (8), 1278-1282 (1985).</li><li>Ding, J. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+extractive+electrospray+ionization+ion+trap+mass+spectrometry+in+vivo+breath+analysis.">Development of extractive electrospray ionization ion trap mass spectrometry in vivo breath analysis.</a> Analyst. 134 (10), 2040-2050 (2009).</li><li>Basum, G., Dahnke, H., Halmer, D., Hering, P., M&#252;rtz, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Online+recording+of+ethane+trances+in+human+breath+via+infrared+laser+spectroscopy.">Online recording of ethane trances in human breath via infrared laser spectroscopy.</a> J. Appl. Physiol. 95 (6), 2583-2590 (2003).</li><li>T&#248;ien, &. #. 2. 1. 6. ;. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Automated+open+flow+respirometry+in+continuous+and+long-term+measurements:+design+and+principles.">Automated open flow respirometry in continuous and long-term measurements: design and principles.</a> J. Appl. Physiol. 114 (8), 1094-1107 (2013).</li><li>Huang, L., Li, X., Xu, M., Huang, Z. X., Zhou, Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identification+of+relatively+high+molecular+weight+compounds+in+human+breath+using+secondary+nano+electrospray+ionization+ultrahigh+resolution+mass+spectrometry.">Identification of relatively high molecular weight compounds in human breath using secondary nano electrospray ionization ultrahigh resolution mass spectrometry.</a> Chem. J. Chinese U. 38 (5), 752-757 (2017).</li></ol>

저자는 공개 없다.

Sec-nanoESI 소스 상용 nanoESI 원본을 기반 구축, 이온화 효율 ESI 소스30을 사용 하 여 보다 높은 수준 이다. 또한, 이온화 효율은 더욱 향상 닫힌된 챔버에 프로세스 분리로 주위 배경 공기에서와 같은 시간을 용이 하 게 가스 샘플 스프레이 깃털 사이 혼합. 초-nanoESI를 사용 하 여 덜 매개 변수는 ESI 소스, 쉽게 설치, 응용 프로그램 및 유지 보수에 비해 최적화가 필요 합니다.
<p class=...

현대 분석 기술의 빠른 개발, 휘발성 유기 화합물 (Voc)의 수백 인간의 exhaled 호흡1에서 확인 되었습니다. 이러한 Voc 치경 공기 (건강 한 성인에 대 한 ~ 350 mL)에서 주로 발생 하 고 해부학 죽은 공간 공기 (~ 150 mL)2, 신체 대사3,,45,6,7에 의해 영향을 받는 ,8 , 환경 오염9, 각각. 결과적으로, 식별,이 Voc 질병 진단과 환경 노출에 대 한 비-침략 적 방식으로 생체로 사용 될 것을 약속 하는.
가스 크로마토그래피 질량 분석 (GC-MS)은 가장 널리 사용 되는 기술 exhaled Voc2의 정성 및 정량 분석을 위해, 실시간 호흡 분석을 위해 개발 되었습니다, 직접 MS 기술을의 장점 높은 시간 해상도 및 간단한 샘플 사전 준비입니다. 직접 MS 기술, 양성자 이전 반응 MS (PTR-MS)10, 같은 선택 이온 흐름 관 석사 (선별-석사)11, 보조 분무 이온화 MS (SESI-MS)12,13 (또한 추출 물 분무로 라는 MS, MS EESI14,15이온화) 추적 대기 가스 분석기 (타가)16 및 플라즈마 이온화 MS (PI-MS)17 는 조사에서 최근 몇 년 동안.
모든 직접 MS 기술, 중 SESI 보편적인 부드러운 이온화 기술19,20,21;로 유명 하다 그리고 소스는 쉽게 사용자 지정 하 여 질량 분석기, 예를 들면, 시간의 비행 질량 분 서 계8,15의 다른 종류를 결합, 이온 트랩 질량 분석기14 그리고 orbitrap 질량 분석기12 ,18. 지금까지, SESI MS는 성공적으로 사용 되었다 호흡기 질환22, 진단 circadian 리듬3,,623, 약 동학7,8, 측정 및 대사 경로4, 등을 밝히고 있다. 가장 최근에, 상업 SESI 소스 사용할 수 있게 했다.
이 연구에서 손쉬운 소형 보조 nanoelectrospray 이온화 소스 (초-nanoESI) 설정 하 고 고해상도 질량 분석기를 결합 했다. 호흡에 exhaled Voc의 실시간 측정을 제시 했다.

<table>
	<tbody>
		<tr>
			<td>Ultrapure water</td>
			<td>Merck Millipore, USA</td>
			<td>MPGP04001</td>
			<td>Resistance &#62;18.2 M&#937;&#183;cm</td>
		</tr>
		<tr>
			<td>Formic acid</td>
			<td>Sigma-Aldrich, USA</td>
			<td>F0507</td>
			<td>Corrosive to the respiratory tract.</td>
		</tr>
		<tr>
			<td>Nitrogen gas</td>
			<td>Guangzhou Shiyuan Gas Co. Ltd., China</td>
			<td>N.A.a</td>
			<td>Purity &#62;99.99%</td>
		</tr>
		<tr>
			<td>Q Exactive hybrid quadrupole-orbitrap mass spectrometer</td>
			<td>Thermo Scientific, USA</td>
			<td>02634L(S/N)</td>
			<td>Beware of high voltage and high temperature</td>
		</tr>
		<tr>
			<td>NanoESI source</td>
			<td>Thermo Scientific, USA</td>
			<td>ES002373(S/N); ES071(P/N)</td>
			<td>Beware of high voltage and high temperature</td>
		</tr>
		<tr>
			<td>Nano LC pump</td>
			<td>Thermo Scientific, USA</td>
			<td>5041.0010A(P/N)</td>
			<td>/</td>
		</tr>
		<tr>
			<td>Xcalibur software (Version 3.0)</td>
			<td>Thermo Scientific, USA</td>
			<td>BRE0008596</td>
			<td>/</td>
		</tr>
		<tr>
			<td>Dino-Lite Digital Microscope</td>
			<td>Tech Video System (SuZhou) Co.Ltd., China</td>
			<td>CQ401833R(S/N)</td>
			<td>/</td>
		</tr>
		<tr>
			<td>Nafion tubing</td>
			<td>Perma Pure LLC, USA</td>
			<td>ME60</td>
			<td>/</td>
		</tr>
		<tr>
			<td>PTFE tubing (I.D. 4 mm)</td>
			<td>Dongguan Hongfu Insulating Material Co. Ltd., China</td>
			<td>N.A.</td>
			<td>Beware of the possible loss of polar compounds</td>
		</tr>
		<tr>
			<td>Mass flow controller</td>
			<td>Line-Tech, Korea</td>
			<td>M15122007 (S/N)</td>
			<td>/</td>
		</tr>
		<tr>
			<td>Flow meter</td>
			<td>Yuyao Industrial Automation Meter Factory, China</td>
			<td>40784</td>
			<td>/</td>
		</tr>
		<tr>
			<td>aN.A.: not available.</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

real-time breath analysis by using secondary nanoelectrospray ionization coupled to high resolution mass spectrometry

비-침략 적 방식으로 질병 진단과 환경 노출에 대 한 생체로 사용할 수 있습니다 이후 exhaled 휘발성 유기 화합물 (Voc) 상당한 관심을 자극 했습니다. 이 작품에서 선물이 고 분해능 질량 분석 (초-nanoESI-HRMS)에 결합 하는 보조 nanoelectrospray 이온화를 사용 하 여 실시간으로 exhaled Voc를 특성화 하는 프로토콜. 수 제 초-nanoESI 소스로 쉽게 세워졌다 기반 상용 nanoESI 소스에. 봉우리의 수백 exhaled 호흡의 배경 뺀 질량 스펙트럼에서 관찰 되었다 그리고 대량 정확도 값은-4.0-13.5 ppm와-20.3-긍정적이 고 부정적인 이온 검출 모드에서 1.3 ppm 각각. 봉우리는 정확한 질량 동위 원소 패턴에 따라 정확한 원소 구성으로 할당 되었다. 30 s 한 증발 기 측정에 사용 되 고 6 복제 된 측정에 대 한 약 7 분 소요.

그림 3 m/z 50-750 모두 긍정적이 고 부정적인 이온 검출 모드에서 기록의 대량 범위에 숨 지를 보여준다. 291 봉우리 (피크 강도 > 5.0x104) 173 봉우리 (피크 강도 > 3.0x104) 긍정적이 고 부정적인 이온 검출 모드에서 배경 빼고 숨 지문에 각각 관찰 되었습니다. 질량 스펙트럼에 봉우리를 식별 하려면 세부 정보12,</...

Watch this Scientific Journal Video about Real-time Breath Analysis by Using Secondary Nanoelectrospray Ionization Coupled to High Resolution Mass Spectrometry at JoVE.com

Real-time Breath Analysis by Using Secondary Nanoelectrospray Ionization Coupled to High Resolution Mass Spectrometry

고 분해능 질량 분석 시연 보조 nanoelectrospray 이온화를 사용 하 여 실시간으로 exhaled 호흡의 화학 성분 특성화에 대 한 프로토콜 결합.

고 분해능 질량 분석을 결합 하는 보조 Nanoelectrospray 이온화를 사용 하 여 실시간 호흡 분석

Exhaled volatile organic compounds (VOCs) have aroused considerable interest, since they can serve as biomarkers for disease diagnosis and environmental ...

real-time-breath-analysis-using-secondary-nanoelectrospray-ionization

Research

JoVE Journal

Chemistry

8.8K 조회수.  Jinan University. 고 분해능 질량 분석 시연 보조 nanoelectrospray 이온화를 사용 하 여 실시간으로 exhaled 호흡의 화학 성분 특성화에 대 한 프로토콜 결합.

비디오: Real-time Breath Analysis by Using Secondary Nanoelectrospray Ionization Coupled to High Resolution Mass Spectrometry

Untargeted Metabolomics from Biological Sources Using Ultraperformance Liquid Chromatography-High Resolution Mass Spectrometry (UPLC-HRMS)

Here we present a workflow to analyze the metabolic profiles for biological samples of interest including; cells, serum, or tissue. The sample is first separated into polar and non-polar fractions by a liquid-liquid phase extraction, and partially purified to facilitate downstream analysis. Both aqueous (polar metabolites) and organic (non-polar metabolites) phases of the initial extraction are processed to survey a broad range of metabolites. Metabolites are separated by different liquid chromatography methods based upon their partition properties. In this method, we present microflow ultra-performance (UP)LC methods, but the protocol is scalable to higher flows and lower pressures. Introduction into the mass spectrometer can be through either general or compound optimized source conditions. Detection of a broad range of ions is carried out in full scan mode in both positive and negative mode over a broad m/z range using high resolution on a recently calibrated instrument. Label-free differential analysis is carried out on bioinformatics platforms. Applications of this approach include metabolic pathway screening, biomarker discovery, and drug development.

Untargeted Metabolomics from Biological Sources Using Ultraperformance Liquid Chromatography-High Resolution Mass Spectrometry UPLC-HRMS

Untargeted metabolomics provides a hypothesis generating snapshot of a metabolic profile. This protocol will demonstrate the extraction and analysis of metabolites from cells, serum, or tissue. A range of metabolites are surveyed using liquid-liquid phase extraction, microflow ultraperformance liquid chromatography/high-resolution mass spectrometry (UPLC-HRMS) coupled to differential analysis software.

Ultraperformance 액체 크로마토 그래피 고해상도 질량 분석 (UPLC-HRMS)를 사용하여 생물 소스에서 타겟이 불분명 한 대사

Here we present a workflow to analyze the metabolic profiles for biological samples of interest including; cells, serum, or tissue. The sample is first ...

연구

화학

A Study of the Complexation of Mercury(II) with Dicysteinyl Tetrapeptides by Electrospray Ionization Mass Spectrometry

In this study we evaluated a method for the characterization of complexes, formed in different relative ratios of mercury(II) to dicysteinyl tetrapeptide, by electrospray ionization orbitrap mass spectrometry. This strategy is based on previous successful characterization of mercury-dicysteinyl complexes involving tripeptides by utilizing mass spectrometry among other techniques. Mercury(II) chloride and a dicysteinyl tetrapeptide were incubated in a degassed buffered medium at varying stoichiometric ratios. The complexes formed were subsequently analyzed on an electrospray mass spectrometer consisting of a hybrid linear ion- and orbi- trap mass analyzer. The electrospray ionization mass spectrometry (ESI-MS) spectra were acquired in the positive mode and the observed peaks were then analyzed for distinct mercury isotopic distribution patterns and associated monoisotopic peak. This work demonstrates that an accurate stoichiometry of mercury and peptide in the complexes formed under specified electrospray ionization conditions can be determined by using high resolution ESI MS based on distinct mercury isotopic distribution patterns.

A Study of the Complexation of MercuryII with Dicysteinyl Tetrapeptides by Electrospray Ionization Mass Spectrometry

The characterization of complexes formed in different relative ratios of mercury(II) to dicysteinyl tetrapeptides by electrospray ionization orbitrap mass spectrometry is presented.

전자 분무 이온화 질량 분석에 의해 Dicysteinyl Tetrapeptides와 수은 (II)의 복합체 형성에 관한 연구

In this study we evaluated a method for the characterization of complexes, formed in different relative ratios of mercury(II) to dicysteinyl tetrapeptide, ...

Rapid High-throughput Species Identification of Botanical Material Using Direct Analysis in Real Time High Resolution Mass Spectrometry

We demonstrate that direct analysis in real time-high resolution mass spectrometry can be used to produce mass spectral profiles of botanical material, and that these chemical fingerprints can be used for plant species identification. The mass spectral data can be acquired rapidly and in a high throughput manner without the need for sample extraction, derivatization or pH adjustment steps. The use of this technique bypasses challenges presented by more conventional techniques including lengthy chromatography analysis times and resource intensive methods. The high throughput capabilities of the direct analysis in real time-high resolution mass spectrometry protocol, coupled with multivariate statistical analysis processing of the data, provide not only class characterization of plants, but also yield species and varietal information. Here, the technique is demonstrated with two psychoactive plant products, Mitragyna speciosa (Kratom) and Datura (Jimsonweed), which were subjected to direct analysis in real time-high resolution mass spectrometry followed by statistical analysis processing of the mass spectral data. The application of these tools in tandem enabled the plant materials to be rapidly identified at the level of variety and species.

A method for species identification of botanical material by direct analysis in real time-high resolution mass spectrometry and multivariate statistical analysis is presented.

실시간 고해상도 질량 분석에 직접 분석을 사용하여 식물 소재의 신속한 높은 처리량 종 확인

We demonstrate that direct analysis in real time-high resolution mass spectrometry can be used to produce mass spectral profiles of botanical material, ...

Fizzy Extraction of Volatile Organic Compounds Combined with Atmospheric Pressure Chemical Ionization Quadrupole Mass Spectrometry

Chemical analysis of volatile and semivolatile compounds dissolved in liquid samples can be challenging. The dissolved components need to be brought to the gas phase, and efficiently transferred to a detection system. Fizzy extraction takes advantage of the effervescence phenomenon. First, a carrier gas (here, carbon dioxide) is dissolved in the sample by applying overpressure and stirring the sample. Second, the sample chamber is decompressed abruptly. Decompression leads to the formation of numerous carrier gas bubbles in the sample liquid. These bubbles assist the release of the dissolved analyte species from the liquid to the gas phase. The released analytes are immediately transferred to the atmospheric pressure chemical ionization interface of a triple quadrupole mass spectrometer. The ionizable analyte species give rise to mass spectrometric signals in the time domain. Because the release of the analyte species occurs over short periods of time (a few seconds), the temporal signals have high amplitudes and high signal-to-noise ratios. The amplitudes and areas of the temporal peaks can then be correlated with concentrations of the analytes in the liquid samples subjected to fizzy extraction, which enables quantitative analysis. The advantages of fizzy extraction include: simplicity, speed, and limited use of chemicals (solvents).

Fizzy extraction is a new laboratory technique for analysis of volatile and semivolatile compounds. A carrier gas is dissolved in the liquid sample by applying overpressure and stirring the sample. The sample chamber is then decompressed. The analyte species are liberated to the gas phase due to effervescence.

Chemical analysis of volatile and semivolatile compounds dissolved in liquid samples can be challenging. The dissolved components need to be brought to ...

Synthesis and Mass Spectrometry Analysis of Oligo-peptoids

Peptoids are sequence-controlled peptide-mimicking oligomers consisting of N-alkylated glycine units. Among many potential applications, peptoids have been thought of as a type of molecular information storage. Mass spectrometry analysis has been considered the method of choice for sequencing peptoids. Peptoids can be synthesized via solid phase chemistry using a repeating two-step reaction cycle. Here we present a method to manually synthesize oligo-peptoids and to analyze the sequence of the peptoids using tandem mass spectrometry (MS/MS) techniques. The sample peptoid is a nonamer consisting of alternating N-(2-methyloxyethyl)glycine (Nme) and N-(2-phenylethyl)glycine (Npe), as well as an N-(2-aminoethyl)glycine (Nae) at the N-terminus. The sequence formula of the peptoid is Ac-Nae-(Npe-Nme)4-NH2, where Ac is the acetyl group. The synthesis takes place in a commercially available solid-phase reaction vessel. The rink amide resin is used as the solid support to yield the peptoid with an amide group at the C-terminus. The resulting peptoid product is subjected to sequence analysis using a triple-quadrupole mass spectrometer coupled to an electrospray ionization source. The MS/MS measurement produces a spectrum of fragment ions resulting from the dissociation of charged peptoid. The fragment ions are sorted out based on the values of their mass-to-charge ratio (m/z). The m/z values of the fragment ions are compared against the nominal masses of theoretically predicted fragment ions, according to the scheme of peptoid fragmentation. The analysis generates a fragmentation pattern of the charged peptoid. The fragmentation pattern is correlated to the monomer sequence of the neutral peptoid. In this regard, MS analysis reads out the sequence information of the peptoids.

A protocol is described for the manual synthesis of oligo-peptoids followed by sequence analysis by mass spectrometry.

합성 및 올리고 peptoids의 질량 분석 분석

Peptoids are sequence-controlled peptide-mimicking oligomers consisting of N-alkylated glycine units. Among many potential applications, peptoids have ...

Characterization of Synthetic Polymers via Matrix Assisted Laser Desorption Ionization Time of Flight (MALDI-TOF) Mass Spectrometry

There are many techniques that can be employed in the characterization of synthetic homopolymers, but few provide as useful of information for end group analysis as matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS). This tutorial demonstrates methods for optimization of the sample preparation, spectral acquisition, and data analysis of synthetic polymers using MALDI-TOF MS. Critical parameters during sample preparation include the selection of the matrix, identification of an appropriate cationization salt, and tuning the relative proportions of the matrix, cation, and analyte. The acquisition parameters, such as mode (linear or reflector), polarization (positive or negative), acceleration voltage, and delay time, are also important. Given some knowledge of the chemistry involved to synthesize the polymer and optimizing both the data acquisition parameters and the sample preparation conditions, spectra should be obtained with sufficient resolution and mass accuracy to enable the unambiguous determination of the end groups of most homopolymers (masses below 10,000) in addition to the repeat unit mass and the overall molecular weight distribution. Though demonstrated on a limited set of polymers, these general techniques are applicable to a much wider range of synthetic polymers for determining mass distributions, though end group determination is only possible for homopolymers with narrow dispersity.

Characterization of Synthetic Polymers via Matrix Assisted Laser Desorption Ionization Time of Flight MALDI-TOF Mass Spectrometry

A protocol for the matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) characterization of synthetic polymers is described including the optimization of sample preparation, spectral acquisition, and data analysis.

매트릭스를 통해 합성 고분자의 특성화 지원 레이저 탈 착 이온화 시간의 비행 (TOF MALDI) 질량 분석

There are many techniques that can be employed in the characterization of synthetic homopolymers, but few provide as useful of information for end group ...

An Efficient Sample Preparation Method to Enhance Carbohydrate Ion Signals in Matrix-assisted Laser Desorption/Ionization Mass Spectrometry

Sample preparation is a critical process in mass spectrometry (MS) analysis of carbohydrates. Although matrix-assisted laser desorption/ionization (MALDI) MS is the method of choice in carbohydrate analysis, poor ion signal and data reproducibility of carbohydrate samples continue to be severe problems. For quantitative analysis of carbohydrates, an effective analytical protocol providing superior data quality is necessary. This video demonstrates sample preparation protocols to improve signal intensity and minimize data variation of carbohydrates in MALDI-MS. After drying and crystallization of sample droplets, the crystal morphology is reformed by methanol before mass spectrometric analysis. The enhancement in carbohydrate signal is examined with MALDI imaging mass spectrometry (IMS). Experimental results show that crystal reformation adjusts crystalline structures and redistributes carbohydrate analytes. In comparison with the dried droplet preparation method in conventional MALDI-MS, reforming carbohydrate crystal morphologies with methanol shows significantly better signal intensity, ion image distribution, and data stability. Since the protocols demonstrated herein do not involve changes in sample composition, they are generally applicable to various carbohydrates and matrixes.

A protocol for enhancing carbohydrate ion signals in MALDI mass spectrometry by reforming crystalline structures during sample preparation processes is demonstrated.

매트릭스 보조 레이저 탈 착/이온화 질량 분석에서 탄수화물 이온 신호를 강화 하는 효율적인 샘플 준비 방법

Sample preparation is a critical process in mass spectrometry (MS) analysis of carbohydrates. Although matrix-assisted laser desorption/ionization (MALDI) ...

High-throughput and Comprehensive Drug Surveillance Using Multisegment Injection-Capillary Electrophoresis-Mass Spectrometry

New analytical methods are urgently needed to enable high-throughput, yet comprehensive drug screening, given an alarming opioid and prescription drug crisis in public health. Conventional urine drug testing based on a two-tier immunoassay screen followed by a gas chromatography-tandem mass spectrometry (GC-MS/MS) or liquid chromatography-tandem mass spectrometry (LC-MS/MS) method are expensive and prone to bias while being limited to targeted panels of known drugs of abuse (DoA). Herein, we outline an improved method for drug surveillance that allows for the resolution and detection of an expanded panel of DoA and their metabolites when using multisegment injection-capillary electrophoresis-mass spectrometry (MSI-CE-MS). Multiplexed separations of ten urine samples with a quality control by CE (&lt; 3 min/sample) in conjunction with full-scan data acquisition using a time-of-flight mass spectrometer (TOF-MS) under positive ion mode detection allows for the identification and quantification of DoA above recommended cut-off levels. An excellent resolution of drug isomers and isobars, including background interferences, are achieved when using MSI-CE-MS with an electrokinetic spacer between sample segments, where accurate mass/molecular formula together with the comigration of a matching deuterated internal standard and the detection of one or more bio-transformed metabolites facilitate DoA identification over a wider detection window. Additionally, urine samples can be analyzed directly without enzyme deconjugation for the rapid screening without complicated sample workup. MSI-CE-MS enables the surveillance of a broad spectrum of DoA that is required for the treatment monitoring of high-risk patients, including confirming prescribed drug adherence, revealing illicit drug use/substitution, and evaluating optimal dosage regimes as required for new advances in precision medicine.

Here we describe a high-throughput method for comprehensive drug surveillance that allows for the improved resolution and detection of large panels of drugs of abuse and their metabolites, with quality control based on multisegment injection-capillary electrophoresis-mass spectrometry.

멀티 주입-모 세관 전기 이동 법 질량 분석을 사용 하 여 높은 처리량 및 포괄적인 약물 감시

New analytical methods are urgently needed to enable high-throughput, yet comprehensive drug screening, given an alarming opioid and prescription drug ...

Imaging Corrosion at the Metal-Paint Interface Using Time-of-Flight Secondary Ion Mass Spectrometry

Corrosion developed at the paint and aluminum (Al) metal-paint interface of an aluminum alloy is analyzed using time-of-flight secondary ion mass spectrometry (ToF-SIMS), illustrating that SIMS is a suitable technique to study the chemical distribution at a metal-paint interface. The painted Al alloy coupons are immersed in a salt solution or exposed to air only. SIMS provides chemical mapping and 2D molecular imaging of the interface, allowing direct visualization of the morphology of the corrosion products formed at the metal-paint interface and mapping of the chemical after corrosion occurs. The experimental procedure of this method is presented to provide technical details to facilitate similar research and highlight pitfalls that may be encountered during such experiments.

Time-of-flight secondary ion mass spectrometry is applied to demonstrate the chemical mapping and corrosion morphology at the metal-paint interface of an aluminum alloy after being exposed to a salt solution compared with a specimen exposed to air.

비행 시간 보조 이온 질량 분석기를 사용 하 여 금속 페인트 인터페이스의 이미징 부식

Corrosion developed at the paint and aluminum (Al) metal-paint interface of an aluminum alloy is analyzed using time-of-flight secondary ion mass ...

Analysis of Complex Molecules and Their Reactions on Surfaces by Means of Cluster-Induced Desorption/Ionization Mass Spectrometry

Desorption/Ionization Induced by Neutral SO2 Clusters (DINeC) is employed as a very soft and efficient desorption/ionization technique for mass spectrometry (MS) of complex molecules and their reactions on surfaces. DINeC is based on a beam of SO2 clusters impacting on the sample surface at low cluster energy. During cluster-surface impact, some of the surface molecules are desorbed and ionized via dissolvation in the impacting cluster; as a result of this dissolvation-mediated desorption mechanism, low cluster energy is sufficient and the desorption process is extremely soft. Both surface adsorbates and molecules of which the surface is composed of can be analyzed. Clear and fragmentation-free spectra from complex molecules such as peptides and proteins are obtained. DINeC does not require any special sample preparation, in particular no matrix has to be applied. The method yields quantitative information on the composition of the samples; molecules at a surface coverage as low as 0.1 % of a monolayer can be detected. Surface reactions such as H/D exchange or thermal decomposition can be observed in real-time and the kinetics of the reactions can be deduced. Using a pulsed nozzle for cluster beam generation, DINeC can be efficiently combined with ion trap mass spectrometry. The matrix-free and soft nature of the DINeC process in combination with the MSn capabilities of the ion trap allows for very detailed and unambiguous analysis of the chemical composition of complex organic samples and organic adsorbates on surfaces.

Neutral SO2 clusters of low kinetic energy (&#60; 0.8 eV/constituent) are used to desorb complex surface molecules such as peptides or lipids for further analysis by means of mass spectrometry using an ion trap mass spectrometer. No special sample preparation is required, and real-time observation of reactions is possible.