More microscopy - 2.3 (5) Flashcards
Module 2, Chapter 2, 2.3, Page 23
What does AFM stand for?
atomic force microscope
What does the atomic force microscope do?
gathers information about a specimen by ‘feeling’ its surface with a mechanical probe
What type of microscopes are AFM and what do they generate?
scanning microscopes that generate three-dimensional images of surfaces
What does an AFM consist of?
a sharp tip (probe) on a cantilever
What is a cantilever?
a lever supported at one end
What is the purpose of the sharp tip used for?
scan the surface of the specimen
When the sharp tip is brought very close to a surface, what happens?
forces between the tip and the specimen cause deflections of the cantilever
How are these deflections measured?
using a laser beam reflected from the top of the cantilever into a detector
What is not required?
fixation and staining
In what conditions can specimens be viewed?
almost normal cell conditions
When specimens are being viewed, can damage be caused?
no - unlike the damage caused during the preparation of specimens for electron microscopy
What can be examined?
living systems
What is the resolution of AFM and is it high or low?
it is very high and has a resolution of 0.1nm
How can information be gained?
at the atomic level, even about the bonds within molecules
What do pharmaceutical industry use AFM for?
to identify potential drug targets on cellular proteins and DNA
What can these microscopes lead to a better understanding of?
how drugs interact with their target molecule or cell
What is AFM also being used for?
to identify new drugs
Finding and identifying new chemical compounds from the natural world takes a…
long time and is expensive
The molecular structures need to be understood before…
their potential use in medicine is known
What can speed up the process in understanding molecular structures?
atomic force microscopes
Can atomic force microscope save money and potentially lives?
yes
What case study is a good example of the importance of AFM?
Deep sea molecules
Case study - In 2010, what type of species did scientists work on?
bacterium from a mud sample
Case study - Where was this mud sample taken from?
the Mariana Trench - the deepest place on the planet
Case study - Where is the Mariana Trench located?
nearly 11 000 metres beneath the pacific ocean
Case study - What did scientists find?
that the bacteria produced an unknown chemical compound
Case study - What was easily determined?
the chemical composition (the number and type of atoms present)
Case study - With the use of atomic force microscopy, what were the scientists able to do?
they were able to image the molecules at very high, atomic level resolution within one week
Case study - What did AFM give scientists?
the molecular structure they needed to know
Case study - Is this the first time AFM had been used in this way?
yes
Case study - What could AFM lead to?
a faster identification of unknown compounds
Case study - What can AFM speed up?
the process of the development of new medicines
