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Flashcards in Analysis and Diagnostics Deck (9)
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1

What is spectroscopy used for?

Chemical analysis, chemical & biochemical
processes, forensics, medical diagnosis
Medical diagnosis, Magnetic Resonance Imaging, MRI
Monitoring climate change, by analysing atmospheric gases
Environment, securing safe water supplies
Biochemical systems – fluorescence labelling
Crime detection, historic and modern, detection of drugs

2

Monitoring climate change and CO2 detection?

Carbon dioxide an important greenhouse gas, excess amounts in the atmosphere effects the climate, to deal with it and asses and prove the extent of the problem you must know how much there is which is where spectroscopy is useful

3

Method of CO2 detection?

Infrared radiation of known intensity in CO2-absorbing wavelengths is transmitted through sampled air and the amount of radiation passing through to a detector is measured and converted to a voltage value on a scale which is carefully calibrated against reference gases of known CO2 concentration

4

Main points of method of CO2 detection?

Spectroscopy points
CO2 absorbing wavelengths - (asymmetric stretch or bend)
Amount of radiation passing through -
(Beer-Lambert – at a specific wavelength)
Carefully calibrated against reference gases - (calibration curves)

5

Monitoring Chemical Reactions using Spectroscopic Analysis?

Common to use UV-vis, IR or Raman spectrometer
Beer Lambert law, absorbance
Choose a reactant or product that has an absorption band at a given wavelength

6

Research using Flow Chemistry / Crystallisation / in situ monitoring?

Devices such as this used for following syntheses and also molecular systems crystallising (such as pharmaceuticals), Monitoring of such reactions uses a range of process analytical tools (including spectroscopy – UV-vis / IR / Raman)

7


Diagnosing Colour-Change Materials – UV-Vis Spectroscopy?

Measurement (and calculation) of the UV- vis spectra from the different coloured forms of the materials, Vital in understanding the origin of the colour, Tells us how the molecules interact in the solid state to generate the colour property

8

Safety of water supply?

Water pollution can cause many problems
Drinking water can become
contaminated with many substances
that can harm human health
Heavy metals from industrial processes can
accumulate in nearby lakes and rivers, can contaminate groundwater and end up in our drinking water supply, heavy metals can slow development, result in birth defects, and have carcinogenic nature
Major water firms do a lot of analytical chemistry using spectroscopy
Analytical methods can measure parts per billion

9

Labelling in biochemistry?

Green Fluorescent Protein (GFP) is a biological marker
Monitoring of physiological processes
Used to visualize protein localization in cells, etc
GFP absorbs in the blue and UV around 390-480nm, and emits (fluoresces!) at 510nm (Green),
GFP can be used to highlight the presence of proteins in cells.
Implanted by using a gene that expresses this protein and attaches it as a tag
Fluorescence process is non-destructive, Can be used in vivo (i.e. to look at living cells and organisms)