이 연구를위한 자금 조달은 USDA-ARS 연구원 프로그램 및 USDA 작물 유전자 원위원회에 의해 부분적으로 제공되었습니다.

1. 감자 덩이 식물의 전분에서 아밀로오스 결정 <ol><li> 껍질과 작은 큐브로 신선한 덩이 줄기를 잘라. </li><li> 작은 갈색 봉투에 감자 큐브를 놓고 C. -80 °에서 하룻밤 저장 </li><li> 나일론 가방과 동결 건조 감자 조각을 전송합니다. </li><li> 동결 건조 후, 박격포와 유 봉 또는 와일리 밀을 사용하여 분말로 감자 샘플을 갈기. </li><li> 50 ㎖ 튜브에, 동결 건조, 지상 괴경 20-30 mg의 샘플을 추가한다. </li><li> 45 %의 솔루션을 준비합니다 (w / v)의 과염소산 (60 % 과염소산 24.4 ㎖ 및 초순수 25.6 ㎖를 혼합한다. </li><li> 45 %의 500 μL (w / v)의 과염소산을 추가하고 흔들거나 전분 과립을 분산 할 소용돌이 친다. </li><li> 실온에서 네 분 배양 기간 후, 용액을 초순수 16 ㎖를 추가하고 텍싱하여 혼합한다. </li><li> 비 수용성 물질이 튜브 바닥에 침전 한 후 (7-10 분 이상), (마이크로 타이 터 플레이트에 용액 40 μl를 전송할모든 입자의 피펫 팅을 피하는). </li><li> 요오드 용액 ​​(2g KI + 1g의 I 초순수 900 ㎖를 2)의 50 μl를 추가하고 피펫 팅하여 샘플을 섞는다. </li><li> 550 nm에서 흡광도를 읽고 (620)는 즉시 nm의. </li><li> 의 농도 범위에서 아밀로스 및 아밀로펙틴 해법에서 생성 표준 곡선과 각 샘플의 아밀로스 / 아밀로펙틴의 비율 (620 nm/550 nm의 흡광도)를 비교하여 아밀로스 비율을 결정한다. 이 절차는 다음에 설명 될 것이다. 테스트 샘플과 함께 빈 (요오드 용액과 과염소산)를 참조하십시오. 사용 분석을위한 데이터를 숨겨진. </li></ol> 2. 아밀로스 / 아밀로펙틴 곡선 <ol><li> 별도의 튜브에서 아밀로오스의 12.5 MG와 아밀로펙틴의 12.5 mg의 무게. </li><li> 45 %의 각 튜브 5 ㎖에 추가 (W / V) 과염소산 완전히 용해. </li><li> 솔루션 (아밀로오스 및 아밀로펙틴) 각각에 대해 초순수 50 ㎖의 최종 부피로 가져온다. </li><li> 6.25 혼합20,625 ML 초순수 사용하여 이전 단계에서 아밀로오스 주식의 ML. 이것은 6.25 ㎎ / ㎖의 아밀로스 솔루션을 만들 것입니다. </li><li> 아밀로펙틴 솔루션에 대해이 절차를 반복합니다. </li><li> 단계 2.4 및 2.5에서 아밀로스 및 아밀로펙틴 표준 용액을 사용하여, 10 % 간격의 표준 곡선을 생성하기 위해 5 ㎖의 최종 부피로 0 ~ 100 %의 아밀로오스 (100~0% 아밀로펙틴) 아르 %의 아밀로스 표준 제조. 예를 들어, 제조 하였다 : 0 % 아밀로오스 / 100 % 아밀로펙틴 표준 피펫 5 ㎖ 아밀로펙틴 솔루션입니다. 10 %의 아밀로스 / 90 % 아밀로펙틴 표준은 0.5 ㎖ 아밀로스와 아밀로펙틴의 4.5 ml의 용액을 배합. 20 %의 아밀로스 / 80 % 아밀로펙틴 표준은 1.0 ml의 아밀로스와 아밀로펙틴의 4.0 ml의 용액을 배합. 30 % 아밀로오스 / 70 % 아밀로펙틴 표준은 1.5 ml의 아밀로오스와 아밀로펙틴 3.5 ml의 솔루션을 결합한다. 40 %의 아밀로오스 / 60 % 아밀로펙틴 표준은 2.0 ml의 아밀로오스와 아밀로펙틴 2.0 ml의 솔루션을 결합한다. 50 %의 아밀로오스/ 50 % 아밀로펙틴 표준, 2.5 ml의 아밀로오스와 아밀로펙틴 2.5 ml의 솔루션을 결합한다. 60 %의 아밀로스 / 40 % 아밀로펙틴 표준은 3.0 ml의 아밀로스 및 아밀로펙틴을 2.0 ㎖의 결합 등). </li><li> 마이크로 플레이트에 각각의 표준 혼합물의 40 μl를 전송합니다. 빈으로 잘 40 ㎕의 45 %와 (w / v)의 과염소산 (가) 있습니다. </li><li> 요오드 용액 ​​(2g KI + 1g의 I 초순수 900 ㎖를 2)의 50 μl를 추가하고 피펫으로 (공백 포함) 각 샘플을 섞는다. </li><li> 550 nm에서 흡광도를 읽고 (620)는 즉시 nm의 각 농도에 대한 아밀로오스 / 아밀로펙틴의 비율을 계산합니다. </li></ol>

<ol>
	<li>Composition Hoover, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=molecular+structure,+and+physicochemical+properties+of+tuber+and+root+starches:+a+review.">molecular structure, and physicochemical properties of tuber and root starches: a review.</a> Carbohydr. 45 (3), 253-267 (2001).</li><li>Bertoft, E., Blennow, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structure+of+Potato+Starch.">Structure of Potato Starch.</a> Advances in Potato Chemistry and Technology. , 83-98 (2009).</li><li>Campbell, M. R., Yeager, H., Abdubek, N., Pollak, L., Glover, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+methods+for+amylose+screening+in+maize+starches+from+exotic+backgrounds.">Comparison of methods for amylose screening in maize starches from exotic backgrounds.</a> Cereal Chem. 79, 317-321 (2002).</li><li>Zhu, T., Jackson, D. S., Wehling, R. L., Geera, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+amylose+determination+methods+and+the+development+of+a+dual+wavelength+iodine+binding+technique.">Comparison of amylose determination methods and the development of a dual wavelength iodine binding technique.</a> Cereal Chem. 85, 51-58 (2008).</li><li>Hovenkamp-Hermelink, J., Devries, J., Adamse, P., Jacobsen, E., Witholt, B., Feenstra, 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+estimation+of+the+amylose+amylopectin+ratio+in+small+amounts+of+tuber+and+leaf+tissue+of+the+potato.">Rapid estimation of the amylose amylopectin ratio in small amounts of tuber and leaf tissue of the potato.</a> Potato Res. 31, 241-246 (1988).</li><li>Shannon, J. C., Garwood, D. L., Boyer, C. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genetics+and+Physiology+of+Starch+Development.">Genetics and Physiology of Starch Development.</a> Starch. , 23-82 (2009).</li><li>Haase, N. U., Plate, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Properties+of+potato+starch+in+relation+to+varieties+and+environmental+factors.">Properties of potato starch in relation to varieties and environmental factors.</a> St&#228;rke. 48 (5), 167-171 (1996).</li><li>Johnston, F. B., Urbas, B., Khanzada, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+storage+on+the+size+distribution+and+amylose/amylopectin+ratio+in+potato+starch+granules.">Effect of storage on the size distribution and amylose/amylopectin ratio in potato starch granules.</a> Am. Pot. J. 45, 315-321 (1968).</li><li>Gibson, T. S., Solah, V. A., McCleary, B. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+procedure+to+measure+amylose+in+cereal+starches+and+flours+with+concanavalin+A.">A procedure to measure amylose in cereal starches and flours with concanavalin A.</a> J. Cereal Sci. 25 (2), 111-119 (1997).</li><li>Sun, S., Matheson, N., Yun, S. -. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Estimation+of+amylose+content+of+starches+after+precipitation+of+amylopectin+by+concanavalin+A.">Estimation of amylose content of starches after precipitation of amylopectin by concanavalin A.</a> Starch. 42, 302-305 (1990).</li></ol>

우리는 공개 아무것도 없어.

감자 괴경의 아밀로스 함량은 일반적으로 20 ~ 35 % 7,8 범위. 가장 값이 범위를 벗어나는 경우, 이러한 오류 가능성 고려 : 1) 원시 데이터가 아밀로오스 / 아밀로펙틴 표준 곡선의 건설 대신 숨겨진 데이터를 사용했다가, 2) 원시 데이터는 아밀로오스의 결정 대신에 숨겨진 데이터를 사용 하였다 / 아밀로펙틴 감자 샘플에서 비율, 또는 3) 해석에 사용하는 물이 충분히 순수하지 않았다. 우리?...

감자 괴경의 신선한 무게의 약 80 %가 물이며, 거의 모든 남아있는 건조 물질의 전분 1입니다. 나머지 동안 아밀로스 전분 (70 %)의 대부분은, 아밀로펙틴으로 구성된다. 아밀로스와 아밀로펙틴의 비율은 전분의 물성을 좌우하는 가장 중요한 속성이다. 아밀로펙틴 알파 1-6 분기 2 선형 알파 1-4 체인 동안 아밀로스는 선형 알파 1-4 포도당 체인입니다. 요오드 등의 방법 바인딩, 시차 주사 열량계 (DSC)는, 고성능 크기 배제 크로마토 그래피 (HPSEC) 및 콘 카나 발린의 상호 작용은 다양한 작물 3,4 전분 판별을 위해 개발되었다. 각 프로토콜은 어려운 한 번에 다수의 샘플을 계량하는 확장 할 만드는 특별한 기술과 장비가 필요합니다. 우리가 여기서 제시하는 방법은 바인딩 듀얼 파장 요오드 Hovenkamp-Hermelink 등. 5에서 수정 된 프로토콜입니다스테인드 전분 과립에 따라 방법. 다른 대이 방법의 장점은 정제하지 않고 원료 전분 아밀로스 판별 및 메서드 4,6의 정밀도를 높이기 위해 이중 파장 시스템의 사용을 포함한다.

<table border="1">
<tbody>
 <tr>
 <td></td>
 <td></td>
 <td></td>
 <td> Reagents</td>
 </tr>
 <tr>
 <td>Amylose </td>
 <td>Sigma</td>
 <td>859656</td>
 <td></td>
 </tr>
 <tr>
 <td>Amylopectin </td>
 <td>Sigma</td>
 <td>A8515</td>
 <td></td>
 </tr>
 <tr>
 <td>Perchloric Acid 60%</td>
 <td>Sigma</td>
 <td>311413</td>
 <td>Very hazardous to skin and eyes</td>
 </tr>
 <tr>
 <td>Iodine</td>
 <td>Sigma</td>
 <td>23214TD</td>
 <td></td>
 </tr>
 <tr>
 <td>Potassium iodide</td>
 <td>Sigma</td>
 <td>08625JE</td>
 <td></td>
 </tr>
 <tr>
 <td></td>
 <td></td>
 <td></td>
 <td>Equipment</td>
 </tr>
 <tr>
 <td>Plate Reader</td>
 <td>Bio Tek</td>
 <td>ELx800</td>
 <td></td>
 </tr>
 </tbody>
</table>

rapid high throughput amylose determination in freeze dried potato tuber samples

이 프로토콜은 요오드와 녹말 포도당 분자 사슬 사이의 복잡한의 형성에 의존 넣어 비색법을 통해 고 설명합니다. 요오드는 아밀로스와 아밀로펙틴 내 긴 사슬 모두와 복합체를 형성한다. 전분 시료에 요오드를 첨가 한 후, 아밀로오스와 아밀로펙틴의 최대 흡수는 각각 620 및 550 nm에서 발생한다. 아밀로스 / 아밀로펙틴의 비율은 620 및 550 nm의 흡광도 값의 비율을 추정하고 특정한 알려진 농도는 흡수 값에 대해 도시 된 표준 곡선에 비교를 할 수있다. 이것은 높은 처리량은, 저렴 방법은 감자 클론의 많은 개체군의 평가를 허용 신뢰성과 재현성이다.

다른 아밀로오스 / 아밀로펙틴 농도 솔루션의 숨겨진 데이터를 구축 표준 곡선은 0.7에서 1.6 (표 1)에 이르기까지 약 흡수 비율을 보여줍니다. 이러한 데이터로부터 선형 회귀 추세선 나중에 동결 건조 감자 샘플 아밀로스 함량 (도 1)를 추론하는 데 사용된다. 공장의 생산 환경은 감자 괴경 7 아밀로스 함량에 대한 몇 가지 효과가 있습니다. 두...

Watch this Scientific Journal Video about Rapid High Throughput Amylose Determination in Freeze Dried Potato Tuber Samples at JoVE.com

Rapid High Throughput Amylose Determination in Freeze Dried Potato Tuber Samples

냉동 건조 된 감자 괴경 샘플의 신속한 높은 처리량 아밀로스 결정

This protocol describes a high through put colorimetric method that relies on the formation of a complex between iodine and chains of glucose molecules in ...

rapid-high-throughput-amylose-determination-freeze-dried-potato-tuber

Research

JoVE Journal

Chemistry

13.8K 조회수.  University of Wisconsin - Madison.  이 프로토콜은 요오드와 녹말 포도당 분자 사슬 사이의 복잡한의 형성에 의존 넣어 비색법을 통해 고 설명합니다. 요오드는 아밀로스와 아밀로펙틴 내 긴 사슬 모두와 복합체를 형성한다. 전분 시료에 요오드를 첨가 한 후, 아밀로오스와 아밀로펙틴의 최대 흡수는 각각 620 및 550 nm에서 발생한다. 아밀로스 / 아밀로펙틴의 비율은 620 및 550 nm의 흡광도 값의 비?...

비디오: Rapid High Throughput Amylose Determination in Freeze Dried Potato Tuber Samples

Rapid Colorimetric Assays to Qualitatively Distinguish RNA and DNA in Biomolecular Samples

Biochemical experimentation generally requires accurate knowledge, at an early stage, of the nucleic acid, protein, and other biomolecular components in potentially heterogeneous specimens. Nucleic acids can be detected via several established approaches, including analytical methods that are spectrophotometric (e.g., A260), fluorometric (e.g., binding of fluorescent dyes), or colorimetric (nucleoside-specific chromogenic chemical reactions).1 Though it cannot readily distinguish RNA from DNA, the A260/A280 ratio is commonly employed, as it offers a simple and rapid2 assessment of the relative content of nucleic acid, which absorbs predominantly near 260 nm and protein, which absorbs primarily near 280 nm. Ratios &lt; 0.8 are taken as indicative of 'pure' protein specimens, while pure nucleic acid (NA) is characterized by ratios &gt; 1.53.
However, there are scenarios in which the protein/NA content cannot be as clearly or reliably inferred from simple uv-vis spectrophotometric measurements. For instance, (i) samples may contain one or more proteins which are relatively devoid of the aromatic amino acids responsible for absorption at &asymp;280 nm (Trp, Tyr, Phe), as is the case with some small RNA-binding proteins, and (ii) samples can exhibit intermediate A260/A280 ratios (~0.8 &lt; ~1.5), where the protein/NA content is far less clear and may even reflect some high-affinity association between the protein and NA components. For such scenarios, we describe herein a suite of colorimetric assays to rapidly distinguish RNA, DNA, and reducing sugars in a potentially mixed sample of biomolecules. The methods rely on the differential sensitivity of pentoses and other carbohydrates to Benedict's, Bial's (orcinol), and Dische's (diphenylamine) reagents; the streamlined protocols can be completed in a matter of minutes, without any additional steps of having to isolate the components. The assays can be performed in parallel to differentiate between RNA and DNA, as well as indicate the presence of free reducing sugars such as glucose, fructose, and ribose (Figure 1).

A suite of colorimetric assays is described for rapidly distinguishing protein, RNA, DNA, and reducing sugars in potentially heterogeneous biomolecular samples.

신속한 Colorimetric Assays는 질적 Biomolecular 샘플에서 RNA와 DNA를 구별 할

Biochemical experimentation generally requires accurate knowledge, at an early stage, of the nucleic acid, protein, and other biomolecular components in ...

연구

화학

A High-throughput-compatible FRET-based Platform for Identification and Characterization of Botulinum Neurotoxin Light Chain Modulators

Botulinum neurotoxin (BoNT) is a potent and potentially lethal bacterial toxin that binds to host motor neurons, is internalized into the cell, and cleaves intracellular proteins that are essential for neurotransmitter release. BoNT is comprised of a heavy chain (HC), which mediates host cell binding and internalization, and a light chain (LC), which cleaves intracellular host proteins essential for acetylcholine release. While therapies that inhibit toxin binding/internalization have a small time window of administration, compounds that target intracellular LC activity have a much larger time window of administrations, particularly relevant given the extremely long half-life of the toxin. In recent years, small molecules have been heavily analyzed as potential LC inhibitors based on their increased cellular permeability relative to larger therapeutics (peptides, aptamers, etc.). Lead identification often involves high-throughput screening (HTS), where large libraries of small molecules are screened based on their ability to modulate therapeutic target function. Here we describe a FRET-based assay with a commercial BoNT/A LC substrate and recombinant LC that can be automated for HTS of potential BoNT inhibitors. Moreover, we describe a manual technique that can be used for follow-up secondary screening, or for comparing the potency of several candidate compounds.

The botulinum neurotoxin type A light chain (BoNT/A LC) is a metalloprotease that enters motor neurons, cleaves its substrate SNAP-25, and disrupts neurotransmission, thereby resulting in flaccid paralysis. Utilizing a high-throughput-compatible FRET-based assay, large libraries of small molecules can be screened for their impact on BoNT/A LC enzymatic activity.

Botulinum neurotoxin (BoNT) is a potent and potentially lethal bacterial toxin that binds to host motor neurons, is internalized into the cell, and ...

Radiolabeling and Quantification of Cellular Levels of Phosphoinositides by High Performance Liquid Chromatography-coupled Flow Scintillation

Phosphoinositides (PtdInsPs) are essential signaling lipids responsible for recruiting specific effectors and conferring organelles with molecular identity and function. Each of the seven PtdInsPs varies in their distribution and abundance, which are tightly regulated by specific kinases and phosphatases. The abundance of PtdInsPs can change abruptly in response to various signaling events or disturbance of the regulatory machinery. To understand how these events lead to changes in the amount of PtdInsPs and their resulting impact, it is important to quantify PtdInsP levels before and after a signaling event or between control and abnormal conditions. However, due to their low abundance and similarity, quantifying the relative amounts of each PtdInsP can be challenging. This article describes a method for quantifying PtdInsP levels by metabolically labeling cells with 3H-myo-inositol, which is incorporated into PtdInsPs. Phospholipids are then precipitated and deacylated. The resulting soluble 3H-glycero-inositides are further extracted, separated by high-performance liquid chromatography (HPLC), and detected by flow scintillation. The labeling and processing of yeast samples is described in detail, as well as the instrumental setup for the HPLC and flow scintillator. Despite losing structural information regarding acyl chain content, this method is sensitive and can be optimized to concurrently quantify all seven PtdInsPs in cells.

Phosphoinositides are signaling lipids whose relative abundance rapidly changes in response to various stimuli. This article describes a method to measure the abundance of phosphoinositides by metabolically labeling cells with 3H-myo-inositol, followed by extraction and deacylation. Extracted glycero-inositides are then separated by high-performance liquid chromatography and quantified by flow scintillation.

고성능 액체 크로마토 그래피 결합 흐름 섬광에 의한 방사성 표지 및 Phosphoinositides의 세포 수준의 정량화

Phosphoinositides (PtdInsPs) are essential signaling lipids responsible for recruiting specific effectors and conferring organelles with molecular ...

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, ...

Extraction and Purification of Polyphenols from Freeze-dried Berry Powder for the Treatment of Vascular Smooth Muscle Cells In Vitro

Epidemiological studies indicate that increased flavonoid intake correlates with decreased mortality due to cardiovascular diseases (CVD) in the United States (US) and Europe. Berries are widely consumed in the US and have a high polyphenolic content. Polyphenols have been shown to interact with many molecular targets and to exert numerous positive biological functions, including antioxidant, anti-inflammatory, and cardioprotective effects. Polyphenols isolated from blackberry (BL), raspberry (RB), and black raspberry (BRB) reduce oxidative stress and cellular senescence in response to angiotensin II (Ang II). This work provides a detailed description of the protocol used to prepare the polyphenol extracts from freeze-dried berries. Polyphenol extractions from freeze-dried berry powder were performed using 80% aqueous ethanol and an ultrasonic-assisted extraction method. The crude extract was further purified and fractionated using chloroform and ethyl acetate, respectively. The effects of both crude and purified extracts were tested on Vascular Smooth Muscle Cells (VSMCs) in culture.

Extraction and Purification of Polyphenols from Freeze-dried Berry Powder for the Treatment of Vascular Smooth Muscle Cells In Vitro

This work details a step-by-step method to prepare polyphenol-rich extracts from freeze-dried berry powder. In addition, it provides a thorough description of how to use these polyphenol-rich extracts in cell culture in the presence of the peptide hormone angiotensin II (Ang II) using Vascular Smooth Muscle Cells (VSMCs).

혈관 평활근 세포 치료를위한 동결 건조 베리 파우더에서 폴리 페놀 추출 및 정제<em&gt; In Vitro</em

Epidemiological studies indicate that increased flavonoid intake correlates with decreased mortality due to cardiovascular diseases (CVD) in the United ...

Disentangling High Strength Copolymer Aramid Fibers to Enable the Determination of Their Mechanical Properties

Traditionally, soft body armor has been made from poly(p-phenylene terephthalamide) (PPTA) and ultra-high molecular weight polyethylene. However, to diversify the fiber choices in the United States body armor market, copolymer fibers based on the combination of 5-amino-2-(p-aminophenyl) benzimidazole (PBIA) and the more conventional PPTA were introduced. Little is known regarding the long-term stability of these fibers, but as condensation polymers, they are expected to have potential sensitivity to moisture and humidity. Therefore, characterizing the strength of the materials and understanding their vulnerability to environmental conditions is important for evaluating their use lifetime in safety applications. Ballistic resistance and other critical structural properties of these fibers are predicated on their strength. To accurately determine the strength of the individual fibers, it is necessary to disentangle them from the yarn without introducing any damage. Three aramid-based copolymer fibers were selected for the study. The fibers were washed with acetone followed by methanol to remove an organic coating that held the individual fibers in each yarn bundle together. This coating makes it difficult to separate single fibers from the yarn bundle for mechanical testing without damaging the fibers and affecting their strength. After washing, fourier transform infrared (FTIR) spectroscopy was performed on both washed and unwashed samples and the results were compared. This experiment has shown that there are no significant variations in the spectra of poly(p-phenylene-benzimidazole-terephthalamide-co-p-phenylene terephthalamide) (PBIA-co-PPTA1) and PBIA-co-PPTA3 after washing, and only a small variation in intensity for PBIA. This indicates that the acetone and methanol rinses are not adversely affecting the fibers and causing chemical degradation. Additionally, single fiber tensile testing was performed on the washed fibers to characterize their initial tensile strength and strain to failure, and compare those to other reported values. Iterative procedural development was necessary to find a successful method for performing tensile testing on these fibers.

The primary goal of the study is to develop a protocol to prepare consistent specimens for accurate mechanical testing of high strength copolymer aramid fibers, by removing a coating and disentangling the individual fiber strands without introducing significant chemical or physical degradation.

그들의 기계적 특성의 결정 수 있도록 고 강도 공중 합체 Aramid 섬유 disentangling

Traditionally, soft body armor has been made from poly(p-phenylene terephthalamide) (PPTA) and ultra-high molecular weight polyethylene. However, to ...

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 ...

Biological Samples Preparation for Speciation at Cryogenic Temperature using High-Resolution  X-Ray Absorption Spectroscopy

The study of elements with X-ray absorption spectroscopy (XAS) is of particular interest when studying the role of metals in biological systems. Sample preparation is a key and often complex procedure, particularly for biological samples. Although X-ray speciation techniques are widely used, no detailed protocol has been yet disseminated for users of the technique. Further, chemical state modification is of concern, and cryo-based techniques are recommended to analyze the biological samples in their near-native hydrated state to provide the maximum preservation of chemical integrity of the cells or tissues. Here, we propose a cellular preparation protocol based on cryo-preserved samples. It is demonstrated in a high energy resolution fluorescence detected X-ray absorption spectroscopy study of selenium in cancer cells and a study of iron in phytoplankton. This protocol can be used with other biological samples and other X-ray techniques that can be damaged by irradiation.

This protocol presents a detailed procedure to prepare biological cryosamples for synchrotron-based X-ray absorption spectroscopy experiments. We describe all the steps required to optimize sample preparation and cryopreservation with examples of the protocol with cancer and phytoplankton cells. This method provides a universal standard of sample cryo-preparation.

고분해능 X선 흡수 분광법을 이용한 극저온에서의 종분화를 위한 생물학적 시료 준비

The study of elements with X-ray absorption spectroscopy (XAS) is of particular interest when studying the role of metals in biological systems. Sample ...

An Externally-Heated Diamond Anvil Cell for Synthesis and Single-Crystal Elasticity Determination of Ice-VII at High Pressure-Temperature Conditions

The externally-heated diamond anvil cell (EHDAC) can be used to generate simultaneously high-pressure and high-temperature conditions found in Earth&#8217;s and planetary interiors. Here we describe the design and fabrication of the EHDAC assemblies and accessories, including ring resistive heaters, thermal and electrical insulating layers, thermocouple placement, as well as the experimental protocol for preparing the EHDAC using these parts. The EHDAC can be routinely used to generate megabar pressures and up to 900 K temperatures in open air, and potentially higher temperatures up to ~1200 K with a protective atmosphere (i.e., Ar mixed with 1% H2). Compared with a laser-heating method for reaching temperatures typically &#62;1100 K, external heating can be easily implemented and provide a more stable temperature at &#8804;900 K and less temperature gradients to the sample. We showcased the application of the EHDAC for synthesis of single crystal ice-VII and studied its single-crystal elastic properties using synchrotron-based X-ray diffraction and Brillouin scattering at simultaneously high-pressure high-temperature conditions.

This work focuses on the standard protocol for preparing the externally-heated diamond anvil cell (EHDAC) for generating high-pressure and high-temperature (HPHT) conditions. The EHDAC is employed to investigate materials in Earth and planetary interiors under extreme conditions, which can be also used in solid state physics and chemistry studies.

고압 온도 조건에서 얼음 VII의 합성 및 단결정 탄성 측정을 위한 외부 가열 다이아몬드 모루 셀

The externally-heated diamond anvil cell (EHDAC) can be used to generate simultaneously high-pressure and high-temperature conditions found in ...

포스포네이트 기반 MOF의 합성 및 발견: 용융열 접근법

Discovery and Synthesis Optimization of Isoreticular Al(III) Phosphonate-Based Metal-Organic Framework Compounds Using High-Throughput Methods

High-throughput (HT) methods are an important tool for the fast and efficient screening of synthesis parameters and the discovery of new materials. This manuscript describes the synthesis of metal-organic frameworks (MOFs) from solution using an HT reactor system, resulting in the discovery of various phosphonate-based MOFs of the composition [Al2H12-x(PMP)3]Clx&#8729;6H2O (H4PMP = N,N &#39;-piperazine bis(methylenephosphonic acid)) for x = 4, 6, denoted as Al-CAU-60-xHCl, containing trivalent aluminum ions. This was accomplished under solvothermal reaction conditions by systematically screening the impact of the molar ratio of the linker to the metal and the pH of the reaction mixture on the product formation. The protocol for the HT investigation includes six steps: a) synthesis planning (DOE = design of&#160;experiment) within the HT methodology, b) dosing and working with in-house developed HT reactors, c) solvothermal synthesis, d) synthesis workup using in-house developed filtration blocks, e) characterization by HT powder X-ray diffraction, and f) evaluation of the data. The HT methodology was first used to study the influence of acidity on the product formation, leading to the discovery of Al-CAU-60&#8729;xHCl (x = 4 or 6).

저자 스포트라이트: 미세 다공성 재료 화학의 발견 가속화 

The targeted synthesis of new metal-organic frameworks (MOFs) is difficult, and their discovery depends on the knowledge and creativity of the chemist. High-throughput methods allow complex synthetic parameter fields to be explored quickly and efficiently, accelerating the process of finding crystalline compounds and identifying synthetic and structural trends.

고처리량 방법을 사용한 isoreticular al(III) phosphonate 기반 금속-유기 프레임워크 화합물의 발견 및 합성 최적화

High-throughput (HT) methods are an important tool for the fast and efficient screening of synthesis parameters and the discovery of new materials. This ...