W5 Biomedical Applications of Infrared and Raman Flashcards

1
Q

how are IR and Raman methods complementary

A

water is a problem in IR but not in Raman

data acquisition is slow in Raman but fast in IR

some bands are strong in IR but weak in Raman and vice versa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is the second derivative of IR spectrum

A

bands in original IR can be broad and overlapping

second derivative os spectra calculated > every maximum in original spectrum becomes a minimum > produce much sharper bands that can be easily quantified in intensity and wavenumber

has very very sharp bands and a flat baseline

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

if given a spectrum, how to tell whether its IR or Raman

A

if IR: y axis is absorbance

if Raman: y axis is intensity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is the most sensitive IR band to secondary structure

A

amide I

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is the most useful IR region for biologists

A

mid IR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

in raman, what is the incident light and what is the emitted light

A

red or nIR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is surface enhanced Raman spectroscopy (SERS)

A

method to solve issue of raman radiation being very weak and thus require long data collections

uses metallic nanostructure to increase intensity of raman scattering signals

enhancement is through resonance between excitation laser and raman scattering with localised surface plasmons (clouds of electrons) in the metallic nanostructure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is the wavelength of beta structure band

A

1635cm-1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is usually used for identification of microorganisms

A

vibrational spectroscopies as different species have different compositions of lipids and proteins > different vibrational spectra

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

why is IR better than hematoxylin and eosin

A

can be used to represent abundance in nucleic acids, proteins or lipids just by selecting different band absorbances in the spectra of the pixels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is the use of raman micro spectroscopy

A

raman radiation is very weak and requires high energy laser beam for excitation

by focussing a laser beam on a very small volume > only that small volume emit significant of raman photons

can scan small volumes in sample and collect raman spectra of each volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly