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Food Industry: The industry concerned with processing, preparing, preserving, distributing, and serving of foods and beverages.

Improved Method for the Establishment of an In Vitro Blood-Brain Barrier Model Based on Porcine Brain Endothelial Cells

1Lundbeck Foundation Research Initiative on Brain Barriers and Drug Delivery, Department of Biomedicine, Aarhus University, 2Institute of Pharmaceutical Science, King's College London, 3HICoE Centre for Drug Research, Universiti Sains Malaysia

JoVE 56277


 Medicine

Gas Chromatography (GC) with Flame-Ionization Detection

JoVE 10187

Source: Laboratory of Dr. B. Jill Venton - University of Virginia

Gas chromatography (GC) is used to separate and detect small molecular weight compounds in the gas phase. The sample is either a gas or a liquid that is vaporized in the injection port. Typically, the compounds analyzed are less than 1,000 Da, because it is difficult to vaporize larger compounds. GC is popular for environmental monitoring and industrial applications because it is very reliable and can be run nearly continuously. GC is typically used in applications where small, volatile molecules are detected and with non-aqueous solutions. Liquid chromatography is more popular for measurements in aqueous samples and can be used to study larger molecules, because the molecules do not need to vaporize. GC is favored for nonpolar molecules while LC is more common for separating polar analytes. The mobile phase for gas chromatography is a carrier gas, typically helium because of its low molecular weight and being chemically inert. Pressure is applied and the mobile phase moves the analyte through the column. The separation is accomplished using a column coated with a stationary phase. Open tubular capillary columns are the most popular columns and have the stationary phase coated on the walls of the capillary. Stationary phases a


 Analytical Chemistry

Production of Chemicals by Klebsiella pneumoniae Using Bamboo Hydrolysate as Feedstock

1Lab of Biorefinery, Shanghai Advanced Research Institute, Chinese Academy of Sciences, 2University of Chinese Academy of Sciences, 3Biorefinery Research Center, Jeonbuk Branch Institute, Korea Research Institute of Bioscience & Biotechnology (KRIBB), 4School of Life Science and Technology, ShanghaiTech University

JoVE 55828


 Bioengineering

Hydrogenation

JoVE 10350

Source: Vy M. Dong and Zhiwei Chen, Department of Chemistry, University of California, Irvine, CA

This experiment will demonstrate the hydrogenation of chalcone as an example of an alkene hydrogenation reaction (Figure 1). In this experiment, palladium on carbon (Pd/C) will be used as a heterogeneous catalyst for the process. A balloon will be used to supply the hydrogen atmosphere. Figure 1: Diagram showing the hydrogenation of chalcone to 3-phenylpropiophenone.


 Organic Chemistry II

Fractional Distillation

JoVE 5700

Source: Laboratory of Dr. Nicholas Leadbeater — University of Connecticut 

Distillation is perhaps the most common laboratory technique employed by chemists for the purification of organic liquids. Compounds in a mixture with different boiling points separate into individual components when the mixture is carefully distilled. The two main types of distillation are "simple distillation" and "fractional distillation", and both are widely used in organic chemistry laboratories. Simple distillation is used when the liquid is (a) relatively pure (containing no more than 10% liquid contaminants), (b) has a non-volatile component, such as a solid contaminant, or (c) is mixed with another liquid with a boiling point that differs by at least 25 °C. Fractional distillation is used when separating mixtures of liquids whose boiling points are more similar (separated by less than 25 °C). This video will detail the fractional distillation of a mixture of two common organic solvents, cyclohexane and toluene.


 Organic Chemistry

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