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Molecular Structure: The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.

Structural Studies of Macromolecules in Solution using Small Angle X-Ray Scattering

1Alberta RNA Research and Training Institute, Department of Chemistry and Biochemistry, University of Lethbridge, 2Department of Biochemistry, University of Alberta, 3Department of Microbiology, Immunology and Infectious Diseases, Cumming School of Medicine, University of Calgary, 4DiscoveryLab, Faculty of Medicine & Dentistry, University of Alberta

JoVE 58538


 Biochemistry

Crystal Structure of the N-terminal Domain of Ryanodine Receptor from Plutella xylostella

1Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency, Collaborative Innovation Center of Chemical Science and Engineering, School of Pharmaceutical Science and Technology, Tianjin University, 2State Key Laboratory of Ecological Pest Control for Fujian/Taiwan Crops and Institute of Applied Ecology, Fujian Agriculture and Forestry University, 3Joint International Research Laboratory of Ecological Pest Control, Ministry of Education, Fuzhou, 4Fujian-Taiwan Joint Centre for Ecological Control of Crop Pests, Fujian Agriculture and Forestry University

JoVE 58568


 Biochemistry

Preparation of Polyoxometalate-based Photo-responsive Membranes for the Photo-activation of Manganese Oxide Catalysts

1Department of Applied Chemistry, The University of Tokyo, 2Clean Energy Research Center, University of Yamanashi, 3Biofunctional Catalyst Research Team, RIKEN Center for Sustainable Resource Science, 4Earth-Life Science Institute (ELSI), Tokyo Institute of Technology, 5Department of Materials Science and Engineering, Tokyo Institute of Technology, 6National Institute for Materials Science

JoVE 58072


 Chemistry

A Practical Guide on Coupling a Scanning Mobility Sizer and Inductively Coupled Plasma Mass Spectrometer (SMPS-ICPMS)

1Bioenergy and Catalysis Laboratory (LBK), Energy and Environment Research Division (ENE), Paul Scherrer Institute, 2Environmental Engineering Institute (IIE), School of Architecture, Civil and Environmental Engineering (ENAC), École; Polytechnique Fédérale de Lausanne (EPFL), 3Institute for Atmospheric and Climate Science ETH Zurich

JoVE 55487


 Chemistry

Glycan Profiling of Plant Cell Wall Polymers using Microarrays

1Australian Centre of Excellence in Plant Cell Walls, School of Botany, University of Melbourne, 2Plant Cell Biology Research Centre, School of Botany, University of Melbourne, 3CSIRO Plant Industry, Black Mountain Laboratories, 4Department of Plant Biology and Biotechnology, University of Copenhagen

JoVE 4238


 Biology

Nanomanipulation of Single RNA Molecules by Optical Tweezers

1Nanoscale Engineering Graduate Program, College of Nanoscale Science and Engineering, University at Albany, State University of New York, 2Nanoscale Science Undergraduate Program, College of Nanoscale Science and Engineering, University at Albany, State University of New York, 3Nanobioscience Constellation, College of Nanoscale Science and Engineering, University at Albany, State University of New York, 4The RNA Institute, University at Albany, State University of New York, 5Department of Biological Sciences, University at Albany, State University of New York

JoVE 51542


 Bioengineering

Raman Spectroscopy for Chemical Analysis

JoVE 5701

Source: Laboratory of Dr. Ryoichi Ishihara — Delft University of Technology

Raman spectroscopy is a technique for analyzing vibrational and other low frequency modes in a system. In chemistry it is used to identify molecules by their Raman fingerprint. In solid-state physics it is used to characterize materials, and more specifically to investigate their crystal structure or crystallinity. Compared to other techniques for investigating the crystal structure (e.g. transmission electron microscope and x-ray diffraction) Raman micro-spectroscopy is non-destructive, generally requires no sample preparation, and can be performed on small sample volumes. For performing Raman spectroscopy a monochromatic laser is shone on a sample. If required the sample can be coated by a transparent layer which is not Raman active (e.g., SiO2) or placed in DI water. The electromagnetic radiation (typically in the near infrared, visible, or near ultraviolet range) emitted from the sample is collected, the laser wavelength is filtered out (e.g., by a notch or bandpass filter), and the resulting light is sent through a monochromator (e.g., a grating) to a CCD detector. Using this, the inelastic scattered light, originating from Raman scattering, can be captured and used to construct the Raman spectrum o


 Analytical Chemistry

Nuclear Magnetic Resonance (NMR) Spectroscopy

JoVE 5680

Source: Laboratory of Dr. Henrik Sundén – Chalmers University of Technology

Nuclear magnetic resonance (NMR) spectroscopy is a vital analysis technique for organic chemists. With the help of NMR, the work in the organic lab has been facilitated tremendously. Not only can it provide information about the structure of a molecule but also determine the content and purity of a sample. Compared with other commonly encountered techniques for organic chemists — such as thermal analysis and mass spectrometry (MS) — NMR is a non-destructive method that is valuable when recovery of the sample is important. One of the most frequently used NMR techniques for an organic chemist is proton (1H) NMR. The protons present in a molecule will behave differently depending on its surrounding chemical environment, making it possible to elucidate its structure. Moreover, it is possible to monitor the completion of a reaction by comparing NMR spectra of the starting material to that of the final product. This video exemplifies how NMR spectroscopy can be used in the everyday work of an organic chemist. The following will be shown: i) preparation of an NMR sample. ii) Using 1H NMR to monitor a reaction. iii) Identifying the product obtained from


 Organic Chemistry

Introduction to Mass Spectrometry

JoVE 5634

Source: Laboratory of Dr. Khuloud Al-Jamal - King's College London

Mass spectrometry is an analytical chemistry technique that enables the identification of unknown compounds within a sample, the quantification of known materials, the determination of the structure, and chemical properties of different molecules.

A mass spectrometer is composed of an ionization source, an analyzer, and a detector. The process involves the ionization of chemical compounds to generate ions. When using inductively coupled plasma (ICP), samples containing elements of interest are introduced into argon plasma as aerosol droplets. The plasma dries the aerosol, dissociates the molecules, and then removes an electron from the components to be detected by the mass spectrometer. Other ionization methods such as electrospray ionization (ESI) and matrix assisted laser desorption ionization (MALDI) are used to analyze biological samples. Following the ionization procedure, ions are separated in the mass spectrometer according to their mass-to-charge ratio (m/z), and the relative abundance of each ion type is measured. Finally, the detector commonly consists in an electron multiplier where the collision of ions with a charged anode leads to a cascade of increasing number of electrons, which can b


 Analytical Chemistry

Growing Crystals for X-ray Diffraction Analysis

JoVE 10216

Source: Laboratory of Dr. Jimmy Franco - Merrimack College

X-ray crystallography is a method commonly used to determine the spatial arrangement of atoms in a crystalline solid, which allows for the determination of the three-dimensional shape of a molecule or complex. Determining the three-dimensional structure of a compound is of particular importance, since a compound's structure and function are intimately related. Information about a compound's structure is often used to explain its behavior or reactivity. This is one of the most useful techniques for solving the three-dimensional structure of a compound or complex, and in some cases it may be the only viable method for determining the structure. Growing X-ray quality crystals is the key component of X-ray crystallography. The size and quality of the crystal is often highly dependent on the composition of the compound being examined by X-ray crystallography. Typically compounds containing heavier atoms produce a greater diffraction pattern, thus require smaller crystals. Generally, single crystals with well-defined faces are optimal, and typically for organic compounds, the crystals need to be larger than those containing heavy atoms. Without viable crystals, X-ray crystallography is not feasible. Some molecules are inherently more crystalline than others, thu


 Organic Chemistry

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