이 작품은 소나타, 프랑스 회사 직원 국립 드 라 공들인 (ANR-13 IS08-0001)와 미국 국립 과학 재단 (National Science Foundation)의 공동 프로젝트에 의해 투자되었다. 크리스틴 Baduel는 ANR-16 ACHN-0026 프로젝트를 통해 프랑스 국립 연구 기관 (ANR)에 의해 지원된다. 또한 저자는 따뜻하게 마리나 Frapa, Rogoznica의, 크로아티아의 에어로졸 샘플링과 도움을 루디어 보스코빅 자그레브 연구소, 크로아티아 마리자 마거스, 아나 Cvitešić, 상하 프르카 밀로사벼빅과 이레나 Ciglenecki을, 감사합니다.

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저자가 공개하는 게 없다.

프로토콜에서 모든 중요한 단계가 설명되어있다. 이들 필터의 에어로졸의 컬렉션을 포함한다 (이중 추출 사용 : SPE를 추출하여 물 추출) 그들로부터 계면 활성제를 추출하고, 추출 (표면 장력 농도 측정)의 분석. 전체 방법, 품질 관리가 빈 필터 (의 추출 및 분석 방법의 적용에 의해 1) 제작 된 편차 &lt;5 mN의 m -1 색채에 대한 검출 한계 미만 표면 장력 흡광도 초순수 비해 2) 농도의 소정 범위의 광 추출 효율과 재현성 / 반복성 포함한 불확실성 추출 계면 활성제의 %를 결정함으로써 법), 3) 비색법에 잠재적 간섭 물질을 선택하여, 해당 방법의 검출을 확인함으로써, 즉 계면 활성제의 타겟 타입 (anioNIC, 양이온 성 및 비이 온성) 참고 문헌 4에 완전히 설명 된대로 다른 보이지 않는 6) 문헌 6에서와 같이 완전히 상세한 비색법에 에어로졸 추출물 잠재적 간섭 물질 (무기 염, 작은 산)을 선택하여. 우리가 알기로,이 문서에 제시된 대기 샘플에서 계면 활성제의 추출 방법은 현재 대기 화학에서 가장 선택적입니다. 특히 훨씬 더 선택적 화합물의 조사 이전에 수행되는 간단한 물 추출 이상이다. (11) (23)가 이러한 에어로졸 샘플에서 고농도에있는 농도의 지표 성과 방해 무기 염 및 작은 유기 산, 이온 성 성분을 제거하기 위해 도시 된 바와 같이, (24) 제 2 추출 단계는 중요ements. (6)이 추출 방법은 또한 표면 및 벌크 시료에 존재하는 모든 계면 활성제를 제거하는 것으로 나타났다. 얻어진 추출물을 따라서 이들 화합물의 정확한 특성화를 허용하도록 충분히 집중된다. 그러나, 계면 활성제 이외에, 다른 비극성 또는 약간 극성 화합물이 대기 에어로졸로부터 추출되는 것이 가능하다. 예를 들어, 일반적으로 샘플링 영역에 따라 유사한 방법 (25)에 의해 추출 된 &quot;부식 형상 물질&quot;(HULIS)는 상기 추출물에 존재할 수있다. 이들 화합물은 단지 약간 우리 활성제 시료 26, 27에있어서 계면 활성제와 비교된다 (28)는 이렇게 측정 한 표면 장력 또는 CMC 크게 기여해서는 안된다. 그러나, 그들은 폴리 산이며 음이온 conce을 방해 할 수<html> ntration 측정. 향후 (그들은 에틸 바이올렛, 음이온 성 계면 활성제를 사용하는 적정 염색 반응 여부 IE) 계면 활성제 농도에 대한 기여도를 결정해야 할 것이다. 기여도가 큰 경우, 추가 단계는 예를 들어 HULIS 아니라 계면 활성제를 포함하는 것 UV-마주 또는 형광에 의해 활성화 된 모든 화합물을 제거하기 위해, 추출 방법에 추가 할 수 있습니다. 지금까지, 에어로졸의 표면 장력의 측정이 논문에 제시된 하나 이상의 에어로졸 계면 활성제 표면 장력 곡선의 다른 방법을 사용할 수 없다. 그것은 대기 샘플과 일치 샘플 볼륨을 필요로 하나가 그대로 걸려 물방울 기술은 이러한 측정을 권장합니다. 직접 추출없이 미크론 크기의 입자의 표면 장력을 측정하는 광학 기술이 개발되고있다. 10,엉덩이 = &quot;외부 참조&quot;&gt; (20), (29)는 지금까지, 그들은 실험실에서 생산 된 입자에만 적용하지만 잠재적으로 언젠가 대기들에 적용될 수있다. 계면 활성제 농도 측정 본 연구에 제시된 비색법 우리의 방법과 같이, 추출 배로 대기 에어로졸 샘플 11, 13, 14, 30 만 물 추출물과하지에 이미 적용되었다. 상기 밑줄로, 제 2 추출 단계는 농도 측정을 방해 무기 염 및 작은 유기산 화합물 등을 제거하고, 이것은 중요한 차이이다. 6 초기 해수 큰 수성 샘플 위해 개발 된 전기 화학적 기술은 또한 ATMOS에서 계면 활성제의 농도를 측정하는 데 사용되어왔다pheric 에어로졸. 얻어진 계면 활성제 농도가 선택한 기준 화합물에 의존하는 모든 계면 활성제의 검출 감도가 동일하다고 가정한다, 즉 31, 32이 방법은 상대적이다. 이 방법에 대해보고 된 검출 한계는 0.02 mg을 L -1 비색 방법에 의해 음이온 성 및 양이온 성 계면 활성제에 대해 0.05 μM의 검출 한계는 0.03 μM 따라서, 기준으로서 테트라 octylphenolethoxylate를 사용하고 유사한 경우. 그러나 때문에 비색법으로 비이 온성 계면 활성제 및 총 농도를 결정의 불확실성, 두 가지 방법 (인터 - 교정)를 비교하는 흥미로운 것이다. 제시된 방법에 몇 점을 더욱 향상시킬 수있다. 모든 비이 온성 계면 활성제 및 재치 동일한 감도를 검출 할 코발트 티오 아닌 다른 염료는 매우 USEF 것UL 및 현재 농도 측정 불확실성의 주요 원천을 줄일 수 있습니다. 이들 화합물은 대기 시료에서 검출 한계에 종종 현재 20 %로 추정 양이온 계면 활성제의 추출 효율도 개선 될 수있다. 이것은 특정 SPE 열을 사용하여, 예를 들어, 수행 할 수있다. 추출 및 적정 조건은 더욱 향상 될 수있다. 예를 들어, 평행 한 세 가지 SPE 셋업에 사용하는 각각의 추출 효율을 개선하고, 방법 (이하 오염 리스크)의 품질을 향상시킬 수있는, 계면 활성제의 종류에 최적화. 시료의 질량 분석 할위한 SPE 카트리지의 최적 흡착제 밀도는 결정되어 있었다. 적정 반응 (PH, 첨가제)에 대한 조건은 추가로 상기 즉, 농도 측정의 감도를 향상 검출 한계를 낮추기 위해 최적화 될 수있다. 분석 자체의 품질을 개선하지 않으면 서 추가 수정은로서는, 에어로졸보다는 수집 된 모든 입자에서 다른 크기 분획에 본 발명의 방법 (즉, 하위 집단)를 적용하는 것과 대기 계면 활성제에 대한 정보 가져다 여기에 제시된. 분석의 다른 유형은 또한 계면 활성제 또는 UV-비스 흡수, 형광, 또는 편광의 화학 구조를 결정하기 위해, 고도로의 존재를 나타 내기 위해 이러한 LC / HR MS 탠덤 MS 나 NMR, 같은 추출에 적용될 수있다 추출물의 공액 또는 키랄 화합물.

구름은 대부분의 환경과 생태계의 문학에 대한, 지구 대기에 필수적이며, 기후 시스템. 그러나 그들의 형성 메커니즘의 일부 측면은 아직 잘 이해되지 않으며, 특히 응축 핵으로서 작용하는 에어로졸 입자에 존재하는 화학 물질의 기여. 이론 1 에어로졸 입자 표면에 존재하는 활성 화합물 또는 계면 활성제가 강하게 형성 그들의 에너지 따라서, 그 표면 장력을 낮춤으로써 구름 방울 형성을 향상시키는 것을 예측한다. 그러나 이러한 효과는 수십 년 동안 관찰에 어려운 유지하고 구름 형성에 계면 활성제의 역할은 현재 모든 클라우드 조사와 대기 및 기후 모델에 대기 지역 사회의 큰 부분에 의해 거부와 무시됩니다. 구름 형성에 어로 졸 계면 활성제의 역할에 대한 이해의 부족에 대한 이유 중 하나는 ISO에 대한 방법의 부재있다후반 그들을 특징. 다른 환경에서 샘플 달리 대기압 샘플의 분석은 매우 작은 샘플 부피와 질량 (여기서, 일반적으로 10 내지 100 μg의 사이), 화학적 복잡성 (염 광물의 혼합물, 및 다양한 유기 물질) 등의 반복 도전 2 대향. 이러한 과제를 극복하고 에어로졸의 이해를 개선하는 것은 특히 대기 에어로졸 샘플로부터 이들 화합물 2) 에어로졸 단계에서 절대 농도를 결정 추출 3) 그 표면 장력 곡선을 결정하는) 몇 가지 방법이 최근 1 우리 그룹에 의해 개발 된 계면 활성제 자신의 임계 미셀 농도 (CMC)를 포함하여 물에 계면 활성제가 표면 포화에 시작되는 농도는 벌크 미셀을 형성한다. 이러한 방법의 최신 버전이 논문에 제시되어있다. 완에 사용될 수있는 추가 개선 및 특성화의 다른 유형제시된 것과 lement이 논의 될 것이다. 이러한 방법의 최근 어플리케이션이 이미 대기 에어로졸 3, 4, 5, 6 및 작용 모드에서의 계면 활성제 농도를 결정하고, 그 자체 (3)이 역할을 증명함으로써 이러한 분석은 구름 형성 계면 활성제의 역할에 대한 이해를 향상시킬 수있는 방법을 도시 한 그들의 생물학적 기원, 3, 4, 7 증명 고전 인스트루먼트 관찰 부족을 설명 구름 방울 형성, 3, 6. 8, 9, 10

<table><tbody><tr><td>Quartz filters</td><td>Fioroni</td><td></td><td>for example &amp;Oslash; 47 mm or &amp;Oslash; 150 mm, Grammage 85 g/m&lt;sup&gt;2&lt;/sup&gt;</td></tr><tr><td>Aluminium foils or glass Petri dishes</td><td></td><td></td><td>baked in oven (773 K, 6&amp;nbsp;h)</td></tr><tr><td>Tweezers, scissors</td><td></td><td></td><td></td></tr><tr><td>Desiccator</td><td></td><td></td><td></td></tr><tr><td colspan="4">&lt;strong&gt;SPE (Solid Phase Extraction) set-up&lt;/strong&gt;</td></tr><tr><td>SPE vacuum manifold Ac-Elut</td><td>Varian&amp;nbsp;</td><td></td><td></td></tr><tr><td>Pump Laboxat</td><td>Knf LAB</td><td></td><td></td></tr><tr><td colspan="4">&lt;strong&gt;Nitrogen dryer set-up&lt;/strong&gt; (hand-made)</td></tr><tr><td>Compressed Nirogen 4.5 in bottle B50, 200 bar at 15 &amp;deg;C</td><td>Linde</td><td></td><td></td></tr><tr><td>Tensiometer</td><td>Dataphysics</td><td>OCA 15EC</td><td></td></tr><tr><td>Tensiometer Software</td><td></td><td>SCA software for OCA version 4-4.1</td><td></td></tr><tr><td>UV-Vis spectrometer</td><td>Agilent</td><td>8453</td><td></td></tr><tr><td>Stir-plates</td><td></td><td></td><td></td></tr><tr><td colspan="4">&lt;strong&gt;Glassware&lt;/strong&gt;</td></tr><tr><td>Glass Petri dishes</td><td></td><td></td><td>for the water extraction step</td></tr><tr><td>Beakers</td><td></td><td></td><td></td></tr><tr><td>15 mL, 30 mL, 60 mL glass bottles with corks</td><td></td><td></td><td></td></tr><tr><td>Tubes for SPE</td><td></td><td></td><td></td></tr><tr><td>Magnetic stirring bars</td><td></td><td></td><td></td></tr><tr><td>Ultrasound bath</td><td></td><td></td><td>for glassware washing</td></tr><tr><td>Micropipettes (0.5 - 5&amp;nbsp;mL, 0.100 - 1&amp;nbsp;mL, 10 - 100 &amp;mu;L)</td><td>Rainin Pipette-Life XLS</td><td></td><td></td></tr><tr><td colspan="4">&lt;strong&gt;Disposable small equipment&lt;/strong&gt;</td></tr><tr><td>Syringe filters 0.45 &amp;mu;m PVDF</td><td>Fisherbrand</td><td></td><td></td></tr><tr><td>SPE C18 cartridges Strata C18-E cartridges 500 mg / 3 mL&amp;nbsp;</td><td>Phenomenex</td><td></td><td></td></tr><tr><td>Plastic syringes</td><td></td><td></td><td></td></tr><tr><td>Needles</td><td></td><td></td><td></td></tr><tr><td>4 mL-vials</td><td></td><td></td><td></td></tr><tr><td>Pasteur glass pipettes</td><td></td><td></td><td></td></tr><tr><td>Micropipette tips</td><td></td><td></td><td></td></tr><tr><td colspan="4">&lt;strong&gt;Chemicals&lt;/strong&gt;</td></tr><tr><td>Sodium dodecyl sulfate (SDS) &amp;ge; 98.5% Bioreagent</td><td>Sigma- Aldrich</td><td>L3771</td><td></td></tr><tr><td>Dioctyl sulfosuccinate sodium salt (AOT) &amp;ge; 97%</td><td>Sigma- Aldrich</td><td>323586</td><td></td></tr><tr><td>Benzyltetradecyldimethylammonium (zephiramine)&amp;nbsp; &amp;ge; 99.0% anhydrous Fluka</td><td>Sigma- Aldrich</td><td>13401</td><td></td></tr><tr><td>Cetyltrimethylammonium chloride solution (CTAC) 25 wt% in H&lt;sub&gt;2&lt;/sub&gt;O</td><td>Sigma- Aldrich</td><td>292737</td><td></td></tr><tr><td>(1,1,3,3-tetramethylbutyl)phenyl-polyethylene glycol (Triton X114) laboratory grade</td><td>Sigma- Aldrich</td><td>X114</td><td></td></tr><tr><td>Polyethylene glycol dodecyl ether (Brij35) Fluka Bio Chemika</td><td>Sigma- Aldrich</td><td>858366</td><td></td></tr><tr><td>L-&amp;alpha;-phosphatidylcholine from egg yolk type XVI-E lyophilized powder &amp;ge;&amp;nbsp;99%</td><td>Sigma- Aldrich</td><td>P3556</td><td></td></tr><tr><td>Surfactin from Bacillus subtilis &amp;ge; 98%</td><td>Sigma- Aldrich</td><td>S3523</td><td></td></tr><tr><td>R-95Dd rhamnolipid (95% dirhamnolipid, 5% monorhamnolipid)</td><td>Sigma- Aldrich</td><td>L510025</td><td></td></tr><tr><td>Ethyl violet cationic triarylmethane dye</td><td>Sigma- Aldrich</td><td>228842</td><td></td></tr><tr><td>Patent Blue VF dye content 50%</td><td>Sigma-Aldrich</td><td>198218</td><td></td></tr><tr><td>Ammonium thiocyanate &amp;ge; 99% puriss. p.a., ACS reagent</td><td>Sigma-Aldrich</td><td>31120</td><td></td></tr><tr><td>Cobalt(II) nitrate hexahydrate &amp;ge; 98% ACS reagent</td><td>Sigma-Aldrich</td><td>239267</td><td></td></tr><tr><td>Acetic anhydride &amp;ge; 99% ReagentPlus</td><td>Sigma-Aldrich</td><td>320102</td><td></td></tr><tr><td>Sodium acetate &amp;ge; 99.0% anhydrous Reagent Plus</td><td>Sigma-Aldrich</td><td>S8750</td><td></td></tr><tr><td>Ethylenediaminetetraacetic acid 99.4&amp;minus; 100.6% ACS reagent powder</td><td>Sigma-Aldrich</td><td>E9884</td><td></td></tr><tr><td>Sodium sulfate anhydrous &amp;ge; 99.0% granulated puriss. p.a. ACS reagent Fluka</td><td>Sigma-Aldrich</td><td>71960</td><td></td></tr><tr><td>Ethanol puriss. p.a. ACS Reagent reag. Ph. Eur. 96% (v/v)</td><td>Sigma-Aldrich</td><td>32294</td><td></td></tr><tr><td>Acetonitrile &amp;ge; 99.9% HiPerSolv CHROMANORM Reag. Ph. Eur. (European Pharmacopoeia Reagent) grade gradient for HPLC</td><td>VWR BDH Prolabo</td><td>20060.32</td><td>to be manipulated under hood</td></tr><tr><td>Chloroform 99% stable with 0.8&amp;minus;1% ethanol</td><td>Alfa Aesar</td><td>L13200-0F</td><td>to be manipulated under hood</td></tr><tr><td>Toluene &gt; 99%</td><td>Chimie Plus</td><td>24053</td><td>to be manipulated under hood</td></tr><tr><td>Denatured ethanol for washing</td><td></td><td></td><td></td></tr><tr><td>Ultra-Pure water</td><td>Ultrapure water system Purelab Classic, Elga</td><td></td><td></td></tr></tbody></table>

extraction and characterization of surfactants from atmospheric aerosols

대기 에어로졸에 존재하는 표면 활성 화합물, 또는 계면 활성제는, 지구의 대기, 기상학, 수 문학의 중심 과정에서 액체 상태의 물이 구름의 형성에 중요한 역할을 할 것으로 기대하고 기후 시스템에있다. 이러한 화합물의 특정 추출 및 특성이 수십 년 동안 부족했기 때문에하지만, 아주 작은 따라서 구름 형성과 지구의 생태계와의 잠재적 인 링크의 완전한 이해를 방지 행동과 기원의 정체성, 특성, 모드에 알려져있다. 본 논문에서는 최근 대기 에어로졸 샘플로부터의 모든 계면 활성제는 1) 타겟 추출 및 그 긴급 포함한 에어로졸 단계에서 절대 농도) (2)의 결정 및 물 3) 자신의 정적 표면 장력 곡선위한 방법을 개발 선물합니다 미셀 농도 (CMC). 이러한 방법은도 9 참조 활성제로 검증되고 난ncluding 음이온 성, 양이온 및 비 이온들. 결과의 예는 나중에 설명하는 개선되게 이외 ​​특성화 크로아티아위한 제안에서 해안 사이트에서 수집 된 미세 에어로졸 입자 (직경 &lt;1 ㎛)에서 발견 활성제 제시된다.

주 : 대기 시료에인가되기 전에,이 섹션에 제시된 모든 프로토콜 9 참조 계면 활성제 표면 장력 곡선 최소 표면 장력 테스트되었고, 수득 된 CMC를 문헌 우수한 일치 하였다. 21 22 1. 농도 의 각각 섹션 2와 3에 기재된 바와 같이 미세 에어로졸은 (&lt;직경 1 ㎛ 또는 &quot;PM1 &#39;) 샘플이 샘플을 처리하고 추출한 2월 2015 년 Rogoznica의 크로아티아 해안 사이트 석영 섬유 필터에 모았다 이 원고. 음이온 성, 양이온 성 및 비이 온성 계면 활성제 에어로졸 샘플 볼륨의 전체 계면 활성제의 농도, C 서핑, P (M)의 농도는 제 4 T에 따라 측정했다그 결과는도 1에 제시하고, 측정 된 계면 활성제 중에서 음이온 성 및 비이 온성 계면 활성제의 지배를 증거. 추출 된 활성제의 샘플과 표면 장력 곡선 2. 표면 장력 도 2에 도시 된 바와 같이, 제 5, 및 농도 측정에 기재된 표면 장력 측정을 결합하여, 동일한 샘플 절대 표면 장력 곡선 결과. 이러한 곡선은 에어로졸 샘플 계면 활성제 농도와 이들 샘플의 표면 장력 ( &quot;σ 분&quot;)를 표시하고 그래픽 CMC 값 (도 2)를 판별 할 수있다. <img alt="그림 1" class="xfigimg" src="/files/ftp_upload/55622/55622fig1.jpg" /> 그림1 : Rogoznica의 크로아티아 수집 미세 에어로졸 (PM1)에서의 계면 활성제 농도. 음이온 (파란색), 양이온 (적색), 비 이온 계면 활성제 (녹색), 총 계면 활성제 농도 에어로졸 위상 (각 계면 활성제의 농도의 합), C 서핑, P (M)에 대한 농도를, 색채 측정 2월 2015 년 Rogoznica의 크로아티아의 해안에서 수집 사이트 미세 (&lt;1 ㎛)의 대기 에어로졸 메소드 결과는 명확하게, 음이온 및 비 이온 계면 활성제의 우위를 나타낸다. <a href="http://ecsource.jove.com/files/ftp_upload/55622/55622fig1large.jpg" target="_blank">이 그림의 더 큰 버전을 보려면 여기를 클릭하십시오.</a> <img alt="그림 2" class="xfigimg" src="/files/ftp_upload/55622/55622fig2.jpg" /> 에어로졸의 계면에서의 일반적인 표면 장력 곡선과 CMC :도 2Rogoznica의, 크로아티아. 표면 장력 농도 측정을 조합 한 2015년 3월 2일의 샘플 절대 계면 활성제 표면 장력 곡선. 흑점은 계면 추출물의 측정 된 표면 장력을 나타낸다. 곡선의 끝에서 오렌지 점은 계산 된 에어로졸 샘플 농도 (단계 4.4.6), 및 &quot;σ 분&quot;의 표면 장력을 나타낸다. CMC의 그래픽 결정이 설명된다. <a href="http://ecsource.jove.com/files/ftp_upload/55622/55622fig2large.jpg" target="_blank">이 그림의 더 큰 버전을 보려면 여기를 클릭하십시오.</a>

Watch this Scientific Journal Video about Extraction and Characterization of Surfactants from Atmospheric Aerosols at JoVE.com

Extraction and Characterization of Surfactants from Atmospheric Aerosols

방법은 대기 에어로졸 본 활성제의 타겟 추출 및 그들의 임계 미셀 농도 (CMC)를 포함하여 물 절대 농도 및 표면 장력 곡선의 측정을 위해 제공된다.

대기 에어로졸의 추출 및 계면 활성제의 특성

Surface-active compounds, or surfactants, present in atmospheric aerosols are expected to play important roles in the formation of liquid water clouds in ...

extraction-characterization-surfactants-from-atmospheric

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JoVE Journal

Environment

16.8K 조회수.  IRCELYON, F-69626.  방법은 대기 에어로졸 본 활성제의 타겟 추출 및 그들의 임계 미셀 농도 (CMC)를 포함하여 물 절대 농도 및 표면 장력 곡선의 측정을 위해 제공된다. 

비디오: Extraction and Characterization of Surfactants from Atmospheric Aerosols

Extraction and Analysis of Microbial Phospholipid Fatty Acids in Soils

Phospholipid fatty acids (PLFAs) are key components of microbial cell membranes. The analysis of PLFAs extracted from soils can provide information about the overall structure of terrestrial microbial communities. PLFA profiling has been extensively used in a range of ecosystems as a biological index of overall soil quality, and as a quantitative indicator of soil response to land management and other environmental stressors.
The standard method presented here outlines four key steps: 1. lipid extraction from soil samples with a single-phase chloroform mixture, 2. fractionation using solid phase extraction columns to isolate phospholipids from other extracted lipids, 3. methanolysis of phospholipids to produce fatty acid methyl esters (FAMEs), and 4. FAME analysis by capillary gas chromatography using a flame ionization detector (GC-FID). Two standards are used, including 1,2-dinonadecanoyl-sn-glycero-3-phosphocholine (PC(19:0/19:0)) to assess the overall recovery of the extraction method, and methyl decanoate (MeC10:0) as an internal standard (ISTD) for the GC analysis.

Phospholipid fatty acids provide information about the structure of soil microbial communities. We present methods for extraction from soil samples with a single-phase chloroform mixture, fractionation of extracted lipids using solid phase extraction columns, and methanolysis to produce fatty acid methyl esters, which are analyzed by capillary gas chromatography.

추출 및 토양의 미생물 인지질 지방산의 분석

Phospholipid fatty acids (PLFAs) are key components of microbial cell membranes. The analysis of PLFAs extracted from soils can provide information about ...

연구

환경과학

Production and Measurement of Organic Particulate Matter in a Flow Tube Reactor

Organic particulate matter (PM) is increasingly recognized as important to the Earth's climate system as well as public health in urban regions, and the production of synthetic PM for laboratory studies have become a widespread necessity. Herein, experimental protocols demonstrate approaches to produce aerosolized organic PM by &#945;-pinene ozonolysis in a flow tube reactor. Methods are described for measuring the size distributions and morphology of the aerosol particles. The video demonstrates basic operations of the flow tube reactor and related instrumentation. The first part of the video shows the procedure for preparing gas-phase reactants, ozonolysis, and production of organic PM. The second part of the video shows the procedures for determining the properties of the produced particle population. The particle number-diameter distributions show different stages of particle growth, namely condensation, coagulation, or a combination of both, depending on reaction conditions. The particle morphology is characterized by an aerosol particle mass analyzer (APM) and a scanning electron microscope (SEM). The results confirm the existence of non-spherical particles that have grown from coagulation for specific reaction conditions. The experimental results also indicate that the flow tube reactor can be used to study the physical and chemical properties of organic PM for relatively high concentrations and short time frames.

This paper describes the operation procedure for the flow tube reactor and related data collection. It shows the protocols for setting the experiments, recording data and generating the number-diameter distribution as well as the particle mass information, which gives useful information about chemical and physical properties of the organic aerosols.

생산 및 흐름 튜브 반응 기에서 유기 미 립 자 물질의 측정

Organic particulate matter (PM) is increasingly recognized as important to the Earth's climate system as well as public health in urban regions, and the ...

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 ...

화학

Composition and Distribution Analysis of Bioaerosols Under Different Environmental Conditions

Variable microorganisms in particulate matter (PM) under different environmental conditions may have significant impacts on human health. In this study, we described a protocol for multiple analyses of the biological compositions in environmental PM. Five experiments are presented: (1) PM number monitoring by using a laser particle counter; (2) PM collection by using a cyclonic aerosol sampler; (3) PM collection by using a high-volume air sampler with filters; (4) culturable microbes collection by the Andersen six-stage sampler; and (5) detection of biological composition of environmental PM by bacterial 16SrDNA and fungal ITS region sequencing. We selected hazy days and a livestock farm as two typical examples of the application in this protocol. In this study, these two sampling methods, cyclonic aerosol sampler and filter sampler, showed different sampling efficiency. The cyclonic aerosol sampler performed much better in terms of collecting bacteria, while these two methods showed the same efficiency in collecting fungi. Filter samplers can work under low temperature conditions while cyclonic aerosol samplers have a sampling limitation for temperature. A solid impacting sampler, such as an Andersen six-stage sampler, can be used to sample bioaerosols directly into the culture medium, which increases the survival rate of culturable microorganisms. However, this method mainly relies on culture while more than 99% of microbes cannot be cultured. DNA extracted from the culturable bacteria collected by the Andersen six-stage sampler and samples collected by cyclonic aerosol sampler and filter sampler were detected by bacterial 16S rDNA and fungal ITS region sequencing.All the methods above may have wide application in many fields of study, such as environmental monitoring and airborne pathogen detection. From these results, we can conclude that these methods can be used under different conditions and may help other researchers further explore the health impacts of environmental bioaerosols.

Understanding the biological composition of environmental particulate matter is important for the study of its significant impacts on human health and disease spread. Here, we used three types of bioaerosol sampling methods and a biological analysis of airborne microbes to better explore airborne microbial communities under different environmental conditions.

구성 및 다른 환경 조건에서 Bioaerosols의 유통 분석

Variable microorganisms in particulate matter (PM) under different environmental conditions may have significant impacts on human health. In this study, ...

Preparation of Hollow Polystyrene Particles and Microcapsules by Radical Polymerization of Janus Droplets Consisting of Hydrocarbon and Fluorocarbon Oils

In this article, we have demonstrated a method for producing hollow particles and microcapsules using oil droplets consisting of hydrocarbon oil (styrene) and fluorocarbon oil (perfluoro-n-octane, PFO) in aqueous surfactant (sodium dodecylsulfate, SDS) solutions. Since fluorocarbon oils are immiscible with hydrocarbon oils, the two oils are separated. Emulsions are prepared by stirring styrene/PFO/aqueous SDS solution mixtures at 80 &#176;C. The type of emulsions and the morphology of droplets in the emulsions are observed by light microscope and scanning confocal fluorescence microscope. It is found that oil droplets with Janus-type morphologies consisting of mutually immiscible styrene and PFO are formed in aqueous SDS solutions. Polystyrene particles are fabricated by radical polymerization of the ternary mixtures of styrene/PFO/aqueous SDS solution at 80 &#176;C. The morphologies of the polystyrene are confirmed by scanning electron microscopy and scanning transmission electron microscopy observations. These observations show the preparation of hollow polystyrene particles with a single hole on the surface. To our knowledge, this method is a novel strategy using the immiscibility of hydrocarbon and fluorocarbon oils. The hollow particles can also be applied to the preparation of microcapsules.

A protocol for the fabrication of hollow polymer particles and microcapsules by radical polymerization using emulsions consisting of styrene, perfluoro-n-octane, and aqueous SDS (sodium dodecylsulfate) solution is presented.

빈 폴리스 티 렌 입자와 탄화수소와 탄 화 불 소 오일을 구성 된 야누스 방울의 과격 한 중 합에 의해 Microcapsules의 준비

In this article, we have demonstrated a method for producing hollow particles and microcapsules using oil droplets consisting of hydrocarbon oil (styrene) ...

Enhanced Oil Recovery using a Combination of Biosurfactants

Biosurfactants are surface-active compounds capable of reducing the surface tension between two phases of different polarities. Biosurfactants have been emerging as promising alternatives to chemical surfactants due to less toxicity, high biodegradability, environmental compatibility and tolerance to extreme environmental conditions. Here, we illustrate the methods used for screening of microbes capable of producing biosurfactants. The biosurfactant producing microbes were identified using drop collapse, oil spreading, and emulsion index assays. Biosurfactant production was validated by determining the reduction in surface tension of the media due to growth of the microbial members. We also describe the methods involved in characterization and identification of biosurfactants. Thin layer chromatography of the extracted biosurfactant followed by differential staining of the plates was performed to determine the nature of the biosurfactant. LCMS, 1H NMR, and FT-IR were used to chemically identify the biosurfactant. We further illustrate the methods to evaluate the application of the combination of produced biosurfactants for enhancing residual oil recovery in a simulated sand pack column.

We illustrate the methods involved in screening and identification of the biosurfactant producing microbes. Methods for chromatographic characterization and chemical identification of the biosurfactants, determining the industrial applicability of the biosurfactant&#160;in enhancing residual oil recovery are also presented.

생체 계면활성제의 조합을 사용한 향상된 오일 회수

Biosurfactants are surface-active compounds capable of reducing the surface tension between two phases of different polarities. Biosurfactants have been ...

Studying Surfactant Effects on Hydrate Crystallization at Oil-Water Interfaces Using a Low-Cost Integrated Modular Peltier Device

We introduce an approach to study the formation and growth of hydrates under the influence of nonionic surfactants. The experimental system includes a temperature regulator, visualization techniques, and inner pressure measurements. The temperature control system contains a low-cost, programmable temperature regulator made with solid-state Peltier components. Along with the temperature control system, we incorporated visualization techniques and internal pressure measurements to study hydrate formation and inhibition in the presence of nonionic surfactants. We studied the hydrate-inhibiting ability of nonionic surfactants (sorbitane monolaurate, sorbitane monooleate, PEG-PPG-PEG, and polyoxyethylenesorbitan tristearate) at low (i.e., 0.1 CMC), medium (i.e., CMC), and high (i.e., 10 CMC) concentrations. Two types of crystals were formed: planar and conical. Planar crystals were formed in plain water and low surfactant concentrations. Conical crystals were formed in high surfactant concentrations. The results of the study show that conical crystals are the most effective in terms of hydrate inhibition. Because conical crystals cannot grow past a certain size, the hydrate growth rate as a conical crystal is slower than the hydrate growth rate as planar crystal. Hence, surfactants that force hydrates to form conical crystals are the most efficient. The goal of the protocol is to provide a detailed description of an experimental system that is capable of investigating the cyclopentane hydrate crystallization process on the surface of a water droplet in the presence of surfactant molecules.

We present a protocol to study the formation of hydrates in the presence of nonionic surfactants on the interface of a water droplet submerged in cyclopentane. The protocol consists of building a low-cost, programmable, temperature regulator. The temperature control system is combined with visualization techniques and internal pressure measurements.

저비용 통합 모듈형 펠티에 장치를 사용하여 오일-워터 인터페이스에서 수화물 결정화에 대한 계면활성제 효과 연구

We introduce an approach to study the formation and growth of hydrates under the influence of nonionic surfactants. The experimental system includes a ...

Capturing Actively Produced Microbial Volatile Organic Compounds from Human-Associated Samples with Vacuum-Assisted Sorbent Extraction

Volatile organic compounds (VOCs) from biological samples have unknown origins. VOCs may originate from the host or different organisms from within the host&#39;s microbial community. To disentangle the origin of microbial VOCs, volatile headspace analysis of bacterial mono- and co-cultures of Staphylococcus aureus, Pseudomonas aeruginosa, and Acinetobacter baumannii, and stable isotope probing in biological samples of feces, saliva, sewage, and sputum were performed. Mono- and co-cultures were used to identify volatile production from individual bacterial species or in combination with stable isotope probing to identify the active metabolism of microbes from the biological samples.
Vacuum-assisted sorbent extraction (VASE) was employed to extract the VOCs. VASE is an easy-to-use, commercialized, solvent-free headspace extraction method for semi-volatile and volatile compounds. The lack of solvents and the near-vacuum conditions used during extraction make developing a method relatively easy and fast when compared to other extraction options such as tert-butylation and solid phase microextraction. The workflow described here was used to identify specific volatile signatures from mono- and co-cultures. Furthermore, analysis of the stable isotope probing of human associated biological samples identified VOCs that were either commonly or uniquely produced. This paper presents the general workflow and experimental considerations of VASE in conjunction with stable isotope probing of live microbial cultures.

This protocol describes the extraction of volatile organic compounds from a biological sample with the vacuum-assisted sorbent extraction method, gas chromatography coupled with mass spectrometry using the Entech Sample Preparation Rail, and data analysis. It also describes culture of biological samples and stable isotope probing.

진공 보조 흡착제 추출을 통해 인간 관련 샘플에서 활발히 생산된 미생물 휘발성 유기 화합물 포획

Volatile organic compounds (VOCs) from biological samples have unknown origins. VOCs may originate from the host or different organisms from within the ...

생화학

Solid-Liquid Extraction

Source: Laboratory of Dr. Jay Deiner &#8212; City University of New York
Extraction is a crucial step in most chemical analyses. It entails removing the analyte from its sample matrix and passing it into the phase required for spectroscopic or chromatographic identification and quantification. When the sample is a solid and the required phase for analysis is a liquid, the process is called solid-liquid extraction. A simple and broadly applicable form of solid-liquid extraction entails combining the solid with a solvent in which the analyte is soluble. Through agitation, the analyte partitions into the liquid phase, which may then be separated from the solid through filtration. The choice of solvent must be made based on the solubility of the target analyte, and on the balance of cost, safety, and environmental concerns.

Solid-Liquid Extraction: Principle, Procedure, Applications

고체 액체 추출

Source: Laboratory of Dr. Jay Deiner &#8212; City University of New York
Extraction is a crucial step in most chemical analyses. It entails removing the ...

교육

JoVE Science Education

유기 화학

Soxhlet Extraction of Lipid Biomarkers from Sediment

Source: Laboratory of Jeff Salacup&#160;- University of Massachusetts Amherst
Every lab needs standards that track the performance, accuracy, and precision of its instruments over time to ensure a measurement made today is the same as a measurement made a year from now (Figure 1). Because standards must test the performance of instruments over a long period of time, large volumes of the standards are often required. Many chemical standards can be purchased from retail scientific companies, like Sigma-Aldrich and Fisher. However, some compounds that occur in nature and that are relevant to paleoclimatic studies have not yet been isolated and purified for purchase. Therefore, these compounds need to be extracted from natural samples, and because of the large volumes of standards required, large volumes of sediment need to be extracted. The Accelerated Solvent Extraction (Dionex) and sonication extractions are not appropriate for the extraction of such large sediment volumes. In these circumstances, a Soxhlet extraction is used.
<img alt="Figure 1" src="/files/ftp_upload/10096/10096fig1.jpg" /> 
Figure 1. Schematic depicting how chemical standard tracks the performance of an instrument through time. The dashed line represents a 1:1 relationship between the accepted and measured (on the instrument) value of a variable. Each star is a weekly measurement of the chemical standard. Green stars represent standards that are accurate. Red stars reflect those that are not accurate indicating that the instrument requires corrective maintenance.