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Capillary Action: A phenomenon in which the surface of a liquid where it contacts a solid is elevated or depressed, because of the relative attraction of the molecules of the liquid for each other and for those of the solid. (from McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)

Thin-Layer Chromatography - Student Protocol

JoVE 11208

Source: Lara Al Hariri at the University of Massachusetts Amherst, MA, USA



Effects of Mobile Phase Composition on Compound Separation

In this section of the lab, you will use TLC to compare how well pure hexane and a mixture of 60% hexane and 40% ethyl acetate can separate phenol, benzoic acid, and butyl phenyl ether by…

 Lab: Chemistry

Adhesion

JoVE 10672

Adhesion occurs when one type of molecule is attracted to a different kind of molecule. Water exhibits adhesive properties in the presence of polar surfaces—like glass or cellulose in plants. Regarding glass, the positively charged hydrogen molecules in water are more attracted to the negatively charged oxygen molecules in the silica than to the oxygen in neighboring water molecules. Capillary action is a result of water’s adhesive tendencies. When a narrow glass tube is inserted into water, the water molecules bind to the tube surface, and the water level inside the tube rises. The smaller the tube diameter, the farther the water rises, because more water molecules are exposed to the glass surface. Capillary action continues as long as the adhesive force is greater than the pull of gravity. Plants use the adhesion of capillary action and cohesion between water molecules to move water up from the roots to the leaves. In plants, xylem vessels consist of long, narrow cells called tracheary elements, which transport water. Because water molecules have an attraction to cellulose, they cling to the xylem cell wall. Cohesive forces between water molecules also attract the water molecules to each other. Together, these forces of adhesion and cohesion create a column of water molecules that gradually moves up the xylem vessels.

 Core: Biology

Thin-Layer Chromatography- Concept

JoVE 11207

Chromatography


Chromatography is a technique used in organic chemistry to separate compounds in a mixture based on their differences in solubility between two different phases. The concept is similar to liquid-liquid extraction, except in chromatography, the two phases consist of the stationary phase and the mobile phase. The stationary phase is a solid —…

 Lab: Chemistry

Performing 1D Thin Layer Chromatography

JoVE 5499

Source: Laboratory of Dr. Yuri Bolshan — University of Ontario Institute of Technology


Thin layer chromatography (TLC) is a chromatographic method used to separate mixtures of non-volatile compounds. A TLC plate consists of a thin layer of adsorbent material (the stationary phase) fixed to an appropriate solid support such as…

 Organic Chemistry

Blood Withdrawal I

JoVE 10246

Source: Kay Stewart, RVT, RLATG, CMAR; Valerie A. Schroeder, RVT, RLATG. University of Notre Dame, IN


Blood collection is a common requirement for research studies that involve mice and rats. The method of blood withdrawal in mice and rats is dependent upon the volume of blood needed, the frequency of the sampling, the health status of the …

 Lab Animal Research

Zebrafish Microinjection Techniques

JoVE 5130

One of the major advantages to working with zebrafish (Danio rerio) is that their genetics can be easily manipulated by microinjection of early stage embryos. Using this technique, solutions containing genetic material or knockdown constructs are delivered into the blastomeres: the embryonic cells sitting atop the yolk of the newly fertilized egg. Delivery into the cytoplasm is…

 Biology II

Photosynthesis- Concept

JoVE 10565

Autotrophs

Almost all living organisms on Earth depend on photosynthesis, which is the process that converts sunlight energy into a simple sugar called glucose. This molecule can be used as a short-term energy source or to build more complex carbohydrates like starches for long-term energy storage. Autotrophs are organisms that capture light energy using photosynthesis. Also known …

 Lab Bio

Overview of BioMEM Devices

JoVE 5788

Bio-microelectromechanical systems, also called BioMEMs, are microscale devices that enable the use of small sample and reagent volumes for diagnostic devices in vivo and in vitro. These devices perform various functions such as filtration, sensing, or synthesis on the microscale, enabling cost savings and improved sensitivity.


 Bioengineering

Using a Hemacytometer to Count Cells

JoVE 5048

Many biomedical experiments require manipulation of a known quantity of cells, in order to achieve accurate, reproducible, and statistically-relevant data. Therefore, learning how to count cells is a particularly essential technique for any successful biomedical scientist. The most common way to count cells is by using a hemacytometer - an instrument that bears two laser-etched grids, which…

 Basic Methods in Cellular and Molecular Biology

Use of an Influenza Antigen Microarray to Measure the Breadth of Serum Antibodies Across Virus Subtypes

1Division of Infectious Diseases, Department of Medicine, University of California Irvine Health, 2Vaccine Research and Development Center, Department of Physiology, University of California Irvine

JoVE 59973

 Immunology and Infection

Production of Genetically Engineered Golden Syrian Hamsters by Pronuclear Injection of the CRISPR/Cas9 Complex

1Department of Animal, Dairy, and Veterinary Sciences, Utah State University, 2National Centre for International Research in Cell and Gene Therapy, Sino-British Research Centre, School of Basic Medical Sciences, Zhengzhou University, 3Department of Animal Science Division of Applied Life Science (BK21 Plus), Gyeongsang National University, 4Institute of Agriculture and Life Science, Gyeongsang National University, 5Centre for Molecular Oncology, Barts Cancer Institute, Queen Mary University of London

JoVE 56263

 Bioengineering

Extraction of Aqueous Metabolites from Cultured Adherent Cells for Metabolomic Analysis by Capillary Electrophoresis-Mass Spectrometry

1Shonai Regional Industry Promotion Center, 2Tsuruoka Metabolomics Laboratory, National Cancer Center, 3Human Metabolome Technologies, Inc, 4Division of Translational Informatics, Exploratory Oncology Research and Clinical Trial Center, National Cancer Center

JoVE 59551

 Cancer Research
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