MN-S는 국립 과학 재단 (National Science Foundation)의 지원을 인정, 루이 저자는 감사 써모 피셔 과학 LTQ Orbitrap XL 질량 분석기의 사용을 위해 그린 즈 버러 노스 캐롤라이나 대학의 인조 질량 분석 시설을 인정 CHE 1011859.을 부여합니다. 저자는이 작품에 대한 유용한 제안과 의견을 그린 즈 버러 노스 캐롤라이나 대학의 다니엘 토드, 빈센트 시카 및 Brandie Erhmann 감사합니다.

참고 : 사용하기 전에 모든 관련 물질 안전 보건 자료 (MSDS)를 참조하시기 바랍니다. 염화 수은은 독성 화학 물질이다. IT와 관련된 모든 솔루션을 전달하는 경우 개인 보호 장비 (장갑, 보안경 및 실험실 코트)를 착용해야합니다. 중금속 지정된 명확하게 표시 화학 폐기물 병에 솔루션을 폐기하십시오. 1. 준비 5 mM의 탈기 암모늄 편대 버퍼, pH가 7.5 <ol><li> HPLC 등급의 물 450 ㎖에 포름산 암모늄 완충액 0.1576 g을 녹인다. 1 M 포름산 7.5에 1 M 수산화 암모늄으로 상기 용액의 pH를 조정한다. 500㎖의 메스 플라스크에이 용액을 전송 및 5mM의 포름산 암모늄 용액을 만들기 위해 검량선을 HPLC 물을 추가한다. </li><li> 아르곤으로 10 분, 퍼지 용 진공 하에서 5mM의 포름산 암모늄 버퍼를 탈기. 두 번 반복 아르곤하에 저장 솔루션입니다. 사용 당일에, 0.2 마이크론 필터 befor를 통해 완충액을 필터E 사용. </li></ol> 수은 (II) 염화물 솔루션 2. 준비 <ol><li> 0.2375 g의 수은 (II) 클로라이드를 달다. 0.035 M 수은 (II) 클로라이드 용액을 제조 5 mM의 포름산 암모늄 완충액 25 ㎖에 용해. </li><li> 7.5 X 10-4 M 용액을 만들 9.785 ㎖의 5 mM로 포름산 암모늄 버퍼에 0.214 ㎖의 0.035 M 수은 (II) 클로라이드 용액을 첨가한다. 아르곤 가스로 7.5 X 10-4 M 수은 (II) 용액 담요. </li></ol> CGGC 원액 3. 준비 <ol><li> HPLC 등급 아세토 니트릴 0.118 ㎖ 중의 dicysteinyl의 테트라, CGGC 2.0 밀리그램을 용해하고 1.0647 ​​㎖의 5 mM의 암모늄 포르 메이트, pH를 5 mM의 CGGC 스톡 용액을 수득 아르곤으로 탈기 한 7.5 완충액 추가. </li><li> 5 mM의 암모늄 형성의 pH 1,275 μL에 7.5 × 10 -4 M CGGC 솔루션을 제공하는 7.5 버퍼를 5 밀리미터 CGGC 주식 솔루션의 225 μl를 추가합니다. </li></ol> 4. 준비수은 (II) 및 CGGC 다양한 반응 혼합물 <ol><li> (1)의 제조 : 0.5 비율의 수은 (II) 용액 CGGC <ol><li> 1.5 ml의 microcentrifuge 관에 5 밀리미터 포름산 암모늄, pH가 7.5 버퍼의 255 μl를 놓습니다. 포름산 암모늄 완충액 1.5 ml의 마이크로 원심 튜브에 7.5 X10 -4 M 수은 (II) 클로라이드 용액 30 μL를 추가한다. </li><li> 10 초에 대한 솔루션을 소용돌이. 그런 다음 1.5 ml의 마이크로 원심에 7.5 × 10 -4 M CGGC 솔루션의 15 μl를 추가합니다. 10 초에 대한 솔루션을 소용돌이. 용액은 질량 분석기로 주입 전에 10 분 동안 방치하자. </li></ol></li><li> 수은의 비율이 1 (II) : 1의 제조 CGGC 용액 <ol><li> 1.5 ml의 microcentrifuge 관에 5 밀리미터 포름산 암모늄, pH가 7.5 버퍼의 240 μl를 놓습니다. 포름산 암모늄 완충액 1.5 ml의 마이크로 원심 튜브에 7.5 X10 -4 M 수은 (II) 클로라이드 용액 30 μL를 추가한다. </li><li> 10 초에 대한 솔루션을 소용돌이. 그때1.5 ml의 microcentrifuge 관에 7.5 × 10 -4 M CGGC 솔루션의 30 μl를 추가합니다. 섹션 4.1에 기재된 바와 같이 유사한 방식으로 반복한다. </li></ol></li><li> 수은의 비율이 2 (II) : 1의 제조 CGGC 용액 <ol><li> 1.5 ml의 microcentrifuge 관에 5 밀리미터 포름산 암모늄, pH가 7.5 버퍼의 210 μl를 놓습니다. 포름산 암모늄 완충액 1.5 ml의 마이크로 원심 튜브에 7.5 X10 -4 M 수은 (II) 클로라이드 용액 30 μL를 추가한다. </li><li> 10 초에 대한 솔루션을 소용돌이. 그런 다음 1.5 ml의 microcentrifuge 관에 7.5 × 10 -4 M CGGC 솔루션의 60 μl를 추가합니다. 섹션 4.1에 기재된 바와 같이 유사한 방식으로 반복한다. </li></ol></li></ol> CEEC 원액 5. 준비 <ol><li> 펩티드를 용해 HPLC 등급 아세토 니트릴 0.145 ㎖ 중의 dicysteinyl의 테트라, CEEC 3.5 밀리그램을 용해. 이어서 13.067 ㎖의 5 mM의 암모늄 포르 메이트의 추가, pH는 아르곤으로 탈기 된 완충액 7.5 0.5 m를 제조M CEEC 솔루션입니다. </li><li> 모든 펩타이드가 용해 될 때까지 용액을 소용돌이. 7.5 × 10 -5 M CEEC 솔루션을 제공하는 1.5 ml의 microcentrifuge 관에, pH가 7.5 버퍼를 CEEC 솔루션 1.125 ml의 0.5 mm의 추가 0.375 ml의 5 ㎜의 포름산 암모늄. 소용돌이 혼합 때까지. </li></ol> 수은 (II) 및 CEEC 솔루션의 다양한 반응 혼합물의 제조 6 <ol><li> (1)의 제조 : 수은 (II)의 비율이 0.5 : CEEC 용액 <ol><li> 1.5 ml의 microcentrifuge 관에 5 밀리미터 포름산 암모늄, pH가 7.5 버퍼의 255 μl를 놓습니다. 포름산 암모늄 완충액 1.5 ml의 마이크로 원심 튜브에 7.5 X10 -4 M 수은 (II) 클로라이드 용액 30 μL를 추가한다. </li><li> 10 초에 대한 솔루션을 소용돌이. 그런 다음 1.5 ml의 microcentrifuge 관에 7.5 × 10 -4 M CEEC 솔루션의 15 μl를 추가합니다. 섹션 4.1에 기재된 바와 같이 유사한 방식으로 반복한다. </li></ol></li><li> 수은 (II)의 1의 비율 : 1의 제조 CEEC 솔루션 <ol><li> (240)를 배치81; 1.5 ml의 마이크로 원심 튜브에 5 mM의 암모늄 포르 메이트, pH가 7.5 완충액 L. 포름산 암모늄 완충액 1.5 ml의 마이크로 원심 튜브에 7.5 X10 -4 M 수은 (II) 클로라이드 용액 30 μL를 추가한다. </li><li> 10 초에 대한 솔루션을 소용돌이. 그런 다음 1.5 ml의 microcentrifuge 관에 7.5 × 10 -4 M CEEC 솔루션의 30 μl를 추가합니다. 섹션 4.1에 기재된 바와 같이 유사한 방식으로 반복한다. </li></ol></li><li> 수은 (II)의 비율이 2 : 1의 제조 CEEC 용액 <ol><li> 1.5 ml의 microcentrifuge 관에 5 밀리미터 포름산 암모늄, pH가 7.5 버퍼의 210 μl를 놓습니다. 포름산 암모늄 완충액 1.5 ml의 마이크로 원심 튜브에 7.5 X10 -4 M 수은 (II) 클로라이드 용액 30 μL를 추가한다. </li><li> 10 초에 대한 솔루션을 소용돌이. 그런 다음 1.5 ml의 microcentrifuge 관에 7.5 × 10 -4 M CEEC 솔루션의 60 μl를 추가합니다. 섹션 4.1에 기재된 바와 같이 유사한 방식으로 반복한다. </li></ol></li></ol> 7. AnalyOrbitrap ESI 질량 분광기 수은 (II) 및 CGGC 샘플의 반응 혼합물 쌩쌩 <ol><li> ESI 질량 분석기 (16)을 준비 <ol><li> 500 μL 유리 주사기로 교정 표준 100 μL를 그린다. </li><li> , MS 펌프의 주사기 크래들에 주사기를 놓고 튜브를 부착하고, 질량 분광 광도계에 주입. </li><li> 파일 아이콘을 선택하고, 파일 이름을 입력하여 실행을 위해 파일 이름을 설정한다. </li><li> 데이터 수집 모듈에서 획득 데이터 버튼을 선택하고 150 스캔을 수집합니다. </li><li> 소프트웨어의 데이터 처리 모듈을 열어 교정 기준을 확인하기 위해 크로마토 그램을 분석한다. 모듈을 열고 메뉴를 파일로 이동하여 &quot;열기&quot;를 선택하고 대화 상자에서 파일을 선택합니다. 크로마토 그램의 피크가 표준 비율을 충전 질량에 상관 관계가 있는지 확인합니다. </li><li> 500 μL를 HPLC 등급 메탄올을 그려 500 μL 유리 주사기를 청소하고 다음 m를 분배비이커에 에탄올. </li><li> 유리 주사기에 HPLC 등급 메탄올 500 μL를 그려 단계 7.1.2에 따라 시스템을 세척하십시오. </li><li> 매개 변수를 설정하기위한 방법의 소프트웨어 설정 모듈을 선택한다. 스캔 모드 메뉴를 선택하고 FTMS와 분석기를 식별 한 후 &quot;확인&quot;을 클릭합니다. 시스 가스 유량 : 10, 소스 온도 : 0, 모세관 전압 : 37 V 튜브 렌즈 : 95 V, 분무 전압 : 4.20 kV로 다음 실시간보기 스펙트럼 페이지에 다양한 아이콘을 클릭하면, 다음과 같은 파라미터를 설정할 , 흐름은 10.00 μL / 분, 분석 평가 : FTMS, 검색 수 : 150. </li></ol></li><li> ESI 질량 분석기에 CGGC 샘플 러닝 <ol><li> 5 mM의 포름산 암모늄의 pH 7.5 버퍼를 실행합니다. <ol><li> , 500 μL 유리 주사기에 5 mM의 포름산 암모늄 버퍼의 500 μl를 놓고 MS 펌프의 주사기 크래들에 배치하고, 튜브를 연결합니다. </li><li> 1 ~ 2 분 동안 튜브를 통해 버퍼를 실행합니다. </li><li> 실행의 파일 이름을 설정파일 아이콘을 선택하고, 파일 이름을 입력하여. </li><li> 모듈에서 획득 데이터 버튼을 선택하고 150 스캔을 수집합니다. </li><li> 150 스캔이 수집 한 후 수집을 중지하려면 실행 버튼을 클릭합니다. </li><li> 데이터 브라우저 모듈을 연 다음 파일 (File) 메뉴로 이동하여 &quot;열기&quot;를 선택하고 대화 상자에서 파일을 선택합니다. 483, 683, 1163 및 1,363m / Z에서 더 피크가 펩타이드 또는 수은 (II) -peptide 단지를 닮은 그 존재하지 않는 것을 확인합니다. </li></ol></li><li> 0.5 수은 (II) : CGGC 비율 솔루션 (1)을 실행합니다. <ol><li> 0.5 수은 (II) : 주사기로 시료의 CGGC 비율 1의 250 μl를 놓습니다. </li><li> 튜브 및 주요 장치를 부착, MS 펌프의 주사기 크래들에 주사기를 놓습니다. </li><li> 파일 아이콘을 선택하고 파일 이름을 입력하여 실행 파일 이름을 선택합니다. </li><li> 데이터 수집 모듈에서 획득 데이터 버튼을 눌러 150 스캔을 수집하고 수집을 중지하려면 실행 버튼을 클릭합니다. </li><li> 모듈을 열고 메뉴를 파일로 이동하여 &quot;열기&quot;를 선택하고 대화 상자에서 파일을 선택합니다. 크로마토 그램 혼자 CGGC 펩타이드에 대한 것을 포함하여 피크가 포함되어 있는지 확인합니다. </li><li> 500 μL 포름산 암모늄 완충액으로 흡인하고 비이커에 포름산 암모늄 버퍼를 분배하여 주사기 씻는다. </li><li> MS의 폐기물 버튼을 선택하고 튜브 500 μL 포름산 암모늄 버퍼로 3 회 세척하십시오. </li><li> 비이커에 메탄올을 분배 한 후 500 ㎕를 메탄올로 흡입에 의해 주사기를 씻으십시오. </li><li> 500 μL 메탄올 튜브를 한 번 플래시합니다. </li><li> MS에로드를 선택 검출기 버튼을 누릅니다. </li><li> 주사기에 포름산 암모늄 버퍼의 500 μl를 추가합니다. </li><li> 튜브 및 주요 장치를 부착, MS 펌프의 주사기 크래들에 주사기를 놓습니다. </li><li> 파일 아이콘을 선택하고, 파일 이름을 입력하여 실행하는 상기 버퍼의 파일 이름을 선택한다. </li><li> 프레스취득 데이터 버튼을 누르고 150 스캔을 수집 한 다음 정지 실행 버튼을 클릭합니다. </li><li> 데이터 브라우저 모듈을 열고 메뉴를 파일로 이동하여 &quot;열기&quot;를 선택하고 대화 상자에서 파일을 선택합니다. CGGC 실행 : 크로마토 그램 이전 수은에서 피크의 무효 확인합니다. </li></ol></li><li> 1 수은 (II) : CGGC 비율 솔루션 (1)을 실행합니다. <ol><li> 주사기에 CGGC 비율 샘플 : 1 수은 (II) : 1 250 μl를 놓습니다. </li><li> 7.2.2.15 스텝 7.2.2.2에 기재 한 것과 유사한 방식으로 반복한다. </li></ol></li><li> 2 수은 (II) : 1을 실행 CGGC 비율 솔루션 <ol><li> 주사기에 CGGC 농도 샘플 : 2 수은 (II) : 1 250 μl를 놓습니다. </li><li> 7.2.2.15 스텝 7.2.2.2에 기재 한 것과 유사한 방식으로 반복한다. </li></ol></li></ol></li></ol> 8. Orbitrap ESI 질량 분석에 의해 반응 혼합물 및 수성 CEEC 샘플 분석 <ol><li> ESI 질량 분석기에 시료를 실행 CEEC <ol><li> 반복 분석 절차 (단계 7.1-7.2) CEEC 샘플 및 다양한 화학 양론 비로 수은 (II) 및 CEEC의 반응 혼합물을 사용. </li></ol></li></ol>

<ol>
	<li>Clifton, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mercury+exposure+and+public+health.">Mercury exposure and public health.</a> Pediatr. Clin. N. Am. 54, 237-269 (2007).</li><li>Andersen, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Principles+and+Recent+Developments+in+Chelation+Treatment+of+Metal+Intoxication.">Principles and Recent Developments in Chelation Treatment of Metal Intoxication.</a> Chem. Rev. 99, 2683-2710 (1999).</li><li>Aposhian, H. V., Maiorino, R. M., Gonzalez-Ramirez, D., Zuniga-Charles, M., Xu, Z., Hurlbut, J. M., Junco-Munoz, P., Dart, R. C., Aposhian, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mobilization+of+heavy+metals+by+newer,+therapeutically+useful+chelating+agents.">Mobilization of heavy metals by newer, therapeutically useful chelating agents.</a> Toxicology. 97, 23-38 (1995).</li><li>Flora, S. J. S., Pachauri, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chelation+in+Metal+Intoxication.">Chelation in Metal Intoxication.</a> Int. J. Environ. Res. Public Health. 7, 2745-2788 (2010).</li><li>Campbell, J. R., Clarkson, T. W., Omar, M. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+therapeutic+use+of+2,3-dimercaptopropane-1-sulfonate+in+two+cases+of+inorganic+mercury+poisoning.">The therapeutic use of 2,3-dimercaptopropane-1-sulfonate in two cases of inorganic mercury poisoning.</a> JAMA. 256, 3127-3130 (1986).</li><li>Rooney, J. P. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+role+of+thiols,+dithiols,+nutritional+factors+and+interacting+ligands+in+the+toxicology+of+mercury.">The role of thiols, dithiols, nutritional factors and interacting ligands in the toxicology of mercury.</a> Toxicology. 234, 145-156 (2007).</li><li>Lin, X., Brooks, J., Bronson, M., Ngu-Schwemlein, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evalution+of+the+association+of+mercury+(II)+with+some+dicysteinyl+tripeptides.">Evalution of the association of mercury (II) with some dicysteinyl tripeptides.</a> Bioorg. Chem. 44, 8-18 (2012).</li><li>Ngu-Schwemlein, M., Lin, X., Rudd, B., Bronson, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthesis+and+ESI+mass+spectrometric+analysis+of+the+association+of+mercury(II)+with+multi-cysteinyl+peptides.">Synthesis and ESI mass spectrometric analysis of the association of mercury(II) with multi-cysteinyl peptides.</a> J. Inorg. Biochem. 133, 8-23 (2014).</li><li>Winther, J. R., Thorpe, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantification+of+thiols+and+disulfides.">Quantification of thiols and disulfides.</a> Biochimica et. Biophysica Acta. 1840, 838-846 (2014).</li><li>D'Agstino, A., Colton, R., Traeger, J. C., Cantry, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+Electrospray+Mass+Spectrometric+Study+of+Organomercury+(II)+and+Mercuric+Interactions+with+Peptides+Involving+Cysteinyl+Ligands.">An Electrospray Mass Spectrometric Study of Organomercury (II) and Mercuric Interactions with Peptides Involving Cysteinyl Ligands.</a> Eur. Mass Spectrom. , 273-285 (1990).</li><li>Hofstadler, S. A., Sannes-Lowery, K. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Applications+of+ESI-MS+in+drug+discovery:+interrogation+of+noncovalent+complexes.">Applications of ESI-MS in drug discovery: interrogation of noncovalent complexes.</a> Nature Reviews Drug Discovery. 5, 585-595 (2006).</li><li>Rubino, F. M., Verduci, C., Giampiccolo, R., Pulvirenti, S., Brambilla, G., Columbi, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Molecular+Characterization+of+Homo-+and+Heterodimeric+Mercury+(II)-bis-thiolates+of+Some+Biologically+Relevant+Thiols+by+Electrospray+Ionization+and+Triple+Quadruple+Tandem+Mass+Spectrometry.">Molecular Characterization of Homo- and Heterodimeric Mercury (II)-bis-thiolates of Some Biologically Relevant Thiols by Electrospray Ionization and Triple Quadruple Tandem Mass Spectrometry.</a> J. Am. Soc. Mass Spectrom. 15, 288-300 (2003).</li><li>Krupp, E. M., Milne, B. F., Mestrot, A., Meharg, A. A., Feldmann, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Investigation+into+mercury+bound+to+biothiols:+structural+identification+using+ESI-ion-trap+MS+and+introduction+of+a+method+for+their+HPLC+separation+with+simultaneous+detection+by+ICP-MS+and+and+ESI-MS.">Investigation into mercury bound to biothiols: structural identification using ESI-ion-trap MS and introduction of a method for their HPLC separation with simultaneous detection by ICP-MS and and ESI-MS.</a> Anal. Bioanal. Chem. 390, 1753-1764 (2008).</li><li>Schauml&#246;ffel, D., Tholey, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+directions+of+electrospray+mass+spectrometry+for+elemental+speciation+analysis.">Recent directions of electrospray mass spectrometry for elemental speciation analysis.</a> Anal. Bioanal. Chem. 400, 1645-1652 (2011).</li><li>Patiny, L., Borel, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=ChemCalc:+a+building+block+for+tomorrow's+chemical+infrastructure.">ChemCalc: a building block for tomorrow's chemical infrastructure.</a> J. Chem. Inf. Model. 53, 1223-1228 (2013).</li><li>Thermo Scientific. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Xcaibur Versions 2.1.0-2.3.0 Data Acquisition and Processing User Guide. Revision E. United States. , (2012).</li><li>Falcone, G., Foti, C., Gianguzza, A., Giuffr&#232;, O., Napoli, A., Pettignano, A., Piazzese, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sequestering+ability+of+some+chelating+agents+towards+methylmercury(II).">Sequestering ability of some chelating agents towards methylmercury(II).</a> Anal. Bioanal. Chem. 405 (2), 881-893 (2013).</li><li>Mah, V., Jalilehvand, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Glutathione+Complex+Formation+with+Mercury(II)+in+Aqueous+Solution+at+Physiological+pH.">Glutathione Complex Formation with Mercury(II) in Aqueous Solution at Physiological pH.</a> Chem. Res. Toxicol. 23, 1815-1823 (2010).</li></ol>

There is no disclosure for the work reported.

소수성 dicysteinyl의 테트라 CGGC (C 10 H 18 N 4 O 5 S 2; MW는 = 338) (도 1), 수은과 복합체를 형성한다 (II)도 2에 도시되고 표 1 또한, 펩티드 이량 체 및 삼량 체를 형성하고있다.이 점진적 반응 혼합물 중의 펩티드의 양이 증가 등. m / z에 연결된 이량 체의 값 [(2M + H) + = 677] 및 삼량 체에 의해 도시 된 바와 같이 [(3M + H)은...

Current clinical drugs prescribed for chelation therapy of mercury poisoning1 contain thiol group(s), which is/are responsible for binding and sequestering mercury ions2,3. However, studies have shown that these small thiol compounds [dimercaptosuccinic acid (DMSA) and dimercaptopropane-sulfonic acid (DMPS)] are not optimal for mercury chelation therapy4-6. Therefore, there is a need to understand the association and complex formation tendencies of mercury with thiols to enhance the rational drug design of thiol compounds for mercury chelation. Recently, we reported that n-alkyl and aryl dicysteinyl tripeptides with dithiol groups can serve as effective "double anchors" to accommodate the coordination sites of mercury(II) to form 1:1 mercury(II):peptide and 1:2 mercury(II):(peptide)2 complexes7. Additionally, we studied the effect of increasing cysteinyl residues on complex type formations8. In this study, we investigate the association of mercury(II) with two dicysteinyl tetrapeptides, where the cysteinyl residues are separated by two amino acid residues. In order to evaluate the effect of auxiliary binding groups for mercury, the intervening amino acids are either two glycine (unsubstituted) residues or two glutamic acid (gamma-carboxylated) residues. 
The reaction of cysteinyl peptide with mercury(II) requires conditions that will prevent the oxidation of the cysteinyl thiol groups to form disulfide bonds9. Moreover, the association of mercury(II) with cysteinyl peptides to form various types of mercury-peptide complexes is dependent on the initial ratio of mercury(II): peptide in the reaction mixture7,8. The types of mercury-peptide complexes formed in these reaction mixtures can be analyzed by soft-ionization mass spectroscopy, which is a sensitive analytical tool for determining species interactions between metal ions and peptides10-14. Accordingly, it will provide a profile of the various types of mercuriated peptide adducts that are formed under a specified electrospray ionization condition. Here, we will show how cysteinyl peptides and mercury(II) chloride solutions can be prepared in degassed ammonium formate buffer solution blanketed with argon to minimize oxidation. By reacting varying mole equivalents of mercury(II) with dicysteinyl tetrapeptides, we will show how the initial ratio of mercury(II):peptide has an effect on the types of complexes formed. We will also show how electrospray ionization (ESI) mass spectrometry can be used as a characterization tool to provide an accurate stoichiometry of mercury to peptide in the complexes formed. The associated video protocol will demonstrate the experimental conditions for preparing the mercury complexes, the procedure for analyzing the reaction mixtures under specified electrospray ionization conditions, and the characterization of the stoichiometries of mercury(II)-dicysteinyl tetrapeptide complexes, based on the distinct mercury isotope distribution patterns, by using the ChemCal program15. It is intended to assist those who are interested in using ESI orbitrap mass spectrometry to analyze various complexes formed by metal ions that exist in different isotopic forms.

<table border="0" cellpadding="0" cellspacing="0" width="573">
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Mercury(II) chloride</td>
			<td style="width:71px;">Sigma-Aldrich</td>
			<td style="width:119px;">429724</td>
			<td style="width:167px;">Highly toxic</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Ammonium formate</td>
			<td style="width:71px;">Sigma-Aldrich</td>
			<td style="width:119px;">516961</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Formic acid</td>
			<td style="width:71px;">Sigma-Aldrich</td>
			<td style="width:119px;">F0507</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Ammonium hydroxide</td>
			<td style="width:71px;">Fisher</td>
			<td>A512-P500</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">HPLC water</td>
			<td style="width:71px;">Fisher</td>
			<td style="width:119px;">W5-4</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">HPLC Acetonitrile</td>
			<td style="width:71px;">Fisher</td>
			<td style="width:119px;">BP2405-1</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">HPLC Methanol</td>
			<td style="width:71px;">Fisher</td>
			<td style="width:119px;">A452-4</td>
			<td></td>
		</tr>
	</tbody>
</table>

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.

<html> 연구는 ESI 질량 분석에 의해 두 tetrapeptides, CGGC 및 CEEC (그림 1)에 사용할 수있는 수은 펩타이드 복합 성분의 특성을 실시 하였다. CGGC 또는 CEEC 수은 (II) 착물은 수은의 혼합물의 반응에 의해 조사 하였다 (II) 및 세 개의 다른 몰비에서 펩티드 용액 : 1 : 0.5, 1 : 1 및 1 : 2 ((II) 수은 : 펩티드) . 수은의 농도 (II)는 7.5 × 10 -6 M이고 펩티드 농도는 그에 따라 ...

Watch this Scientific Journal Video about A Study of the Complexation of MercuryII with Dicysteinyl Tetrapeptides by Electrospray Ionization Mass Spectrometry at JoVE.com

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, ...

a-study-complexation-mercury-ii-with-dicysteinyl-tetrapeptides

Research

JoVE Journal

Chemistry

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

7.8K 조회수.  University of North Carolina at Greensboro. The characterization of complexes formed in different relative ratios of mercury(II) to dicysteinyl tetrapeptides by electrospray ionization orbitrap mass spectrometry is presented.

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

Visualization of Ambient Mass Spectrometry with the Use of Schlieren Photography

This manuscript outlines how to visualize mass spectrometry ambient ionization sources using schlieren photography. In order to properly optimize the mass spectrometer, it is necessary to characterize and understand the physical principles of the source. Most commercial ambient ionization sources utilize jets of nitrogen, helium, or atmospheric air to facilitate the ionization of the analyte. As a consequence, schlieren photography can be used to visualize the gas streams by exploiting the differences in refractive index between the streams and ambient air for visualization in real time. The basic setup requires a camera, mirror, flashlight, and razor blade. When properly configured, a real time image of the source is observed by watching its reflection. This allows for insight into the mechanism of action in the source, and pathways to its optimization can be elucidated. Light is shed on an otherwise invisible situation.

This paper presents a protocol for the visualization of gaseous streams of an ambient ionization source using schlieren photography and mass spectrometry.

슐 리렌 사진의 사용과 주변 질량 분석의 시각화

This manuscript outlines how to visualize mass spectrometry ambient ionization sources using schlieren photography. In order to properly optimize the mass ...

연구

화학

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 ...

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

Exhaled volatile organic compounds (VOCs) have aroused considerable interest, since they can serve as biomarkers for disease diagnosis and environmental exposure in a non-invasive manner. In this work, we present a protocol to characterize the exhaled VOCs in real time by using secondary nanoelectrospray ionization coupled to high resolution mass spectrometry (Sec-nanoESI-HRMS). The homemade Sec-nanoESI source was readily set up based on a commercial nanoESI source. Hundreds of peaks were observed in the background-subtracted mass spectra of exhaled breath, and the mass accuracy values are -4.0-13.5 ppm and -20.3-1.3 ppm in the positive and negative ion detection modes, respectively. The peaks were assigned with accurate elemental composition according to the accurate mass and isotopic pattern. Less than 30 s is used for one exhalation measurement, and it takes approximately 7 min for six replicated measurements.

A protocol for characterizing chemical composition of exhaled breath in real time by using secondary nanoelectrospray ionization coupled to high resolution mass spectrometry is demonstrated.

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 ...

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) ...

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.

클러스터 유도 탈착/이온화 질량 분광법에 의한 표면에 대한 복잡한 분자 및 표면의 반응 분석

Desorption/Ionization Induced by Neutral SO2 Clusters (DINeC) is employed as a very soft and efficient desorption/ionization technique for mass ...

Capillary Electrophoresis Mass Spectrometry Approaches for Characterization of the Protein and Metabolite Corona Acquired by Nanomaterials

The adsorption of biomolecules from surrounding biological matrices to the surface of nanomaterials (NMs) to form the corona has been of interest for the past decade. Interest in the bio-nano interface arises from the fact that the biomolecular corona confers a biological identity to NMs and thus causes the body to identify them as &#8220;self&#8221;. For example, previous studies have demonstrated that the proteins in the corona are capable of interacting with membrane receptors to influence cellular uptake and established that the corona is responsible for cellular trafficking of NMs and their eventual toxicity. To date, most research has focused upon the protein corona and overlooked the possible impacts of the metabolites included in the corona or synergistic effects between components in the complete biomolecular corona. As such, this work demonstrates methodologies to characterize both the protein and metabolite components of the biomolecular corona using bottom-up proteomics and metabolomics approaches in parallel. This includes an on-particle digest of the protein corona with a surfactant used to increase protein recovery, and a passive characterization of the metabolite corona by analyzing metabolite matrices before and after NM exposures. This work introduces capillary electrophoresis &#8211; mass spectrometry (CESI-MS) as a new technique for NM corona characterization. The protocols outlined here demonstrate how CESI-MS can be used for the reliable characterization of both the protein and metabolite corona acquired by NMs. The move to CESI-MS greatly decreases the volume of sample required (compared to traditional liquid chromatography &#8211; mass spectrometry (LC-MS) approaches) with multiple injections possible from as little as 5 &#181;L of sample, making it ideal for volume limited samples. Furthermore, the environmental consequences of analysis are reduced with respect to LC-MS due to the low flow rates (&#60;20 nL/min) in CESI-MS, and the use of aqueous electrolytes which eliminates the need for organic solvents.

Here we present a protocol to characterize the complete biomolecular corona, proteins, and metabolites, acquired by nanomaterials from biofluids using a capillary electrophoresis &#8211; mass spectrometry approach.

나노 물질에 의해 획득 된 단백질과 대사 산물 코로나특성화를위한 모세관 전기 전구 질량 분광법 접근법

The adsorption of biomolecules from surrounding biological matrices to the surface of nanomaterials (NMs) to form the corona has been of interest for the ...

Covalent Labeling with Diethylpyrocarbonate for Studying Protein Higher-Order Structure by Mass Spectrometry

Characterizing a protein&#39;s higher-order structure is essential for understanding its function. Mass spectrometry (MS) has emerged as a powerful tool for this purpose, especially for protein systems that are difficult to study by traditional methods. To study a protein&#39;s structure by MS, specific chemical reactions are performed in solution that encode a protein&#39;s structural information into its mass. One particularly effective approach is to use reagents that covalently modify solvent accessible amino acid side chains. These reactions lead to mass increases that can be localized with residue-level resolution when combined with proteolytic digestion and tandem mass spectrometry. Here, we describe the protocols associated with use of diethylpyrocarbonate (DEPC) as a covalent labeling reagent together with MS detection. DEPC is a highly electrophilic molecule capable of labeling up to 30% of the residues in the average protein, thereby providing excellent structural resolution. DEPC has been successfully used together with MS to obtain structural information for small single-domain proteins, such as &#946;2-microglobulin, to large multi-domain proteins, such as monoclonal antibodies.

The experimental procedures for performing diethylpyrocarbonate-based covalent labeling with mass spectrometric detection are described. Diethylpyrocarbonate is simply mixed with the protein or protein complex of interest, leading to the modification of solvent accessible amino acid residues. The modified residues can be identified after proteolytic digestion and liquid chromatography/mass spectrometry analysis.

질량 분광법에 의한 단백질 고차 구조를 연구하기 위한 디틸피로카보네이트와 공유 라벨링

Characterizing a protein&#39;s higher-order structure is essential for understanding its function. Mass spectrometry (MS) has emerged as a powerful tool ...

Organic Solvent-Based Protein Precipitation for Robust Proteome Purification Ahead of Mass Spectrometry

While multiple advances in mass spectrometry (MS) instruments have improved qualitative and quantitative proteome analysis, more reliable front-end approaches to isolate, enrich, and process proteins ahead of MS are critical for successful proteome characterization. Low, inconsistent protein recovery and residual impurities such as surfactants are detrimental to MS analysis. Protein precipitation is often considered unreliable, time-consuming, and technically challenging to perform compared to other sample preparation strategies. These concerns are overcome by employing optimal protein precipitation protocols. For acetone precipitation, the combination of specific salts, temperature control, solvent composition, and precipitation time is critical, while the efficiency of chloroform/methanol/water precipitation depends on proper pipetting and vial manipulation. Alternatively, these precipitation protocols are streamlined and semi-automated within a disposable spin cartridge. The expected outcomes of solvent-based protein precipitation in the conventional format and using a disposable, two-stage filtration and extraction cartridge are illustrated in this work. This includes the detailed characterization of proteomic mixtures by bottom-up LC-MS/MS analysis. The superior performance of SDS-based workflows is also demonstrated relative to non-contaminated protein.

The present protocol describes solvent-based protein precipitation under controlled conditions for robust and rapid recovery and purification of proteome samples prior to mass spectrometry.

While multiple advances in mass spectrometry (MS) instruments have improved qualitative and quantitative proteome analysis, more reliable front-end ...