Diagnostics

Question 1

What is diagnostics?

Answer 1

It is used to determine what something is (eg. Tests for diseases or tests for a particular pathogen).

Question 2

What are the classical approaches to diagnostics?

Answer 2

Colony counting and microscopy.

But these are slow and not very accurate.

Question 3

What are the immunological techniques in diagnostics?

Answer 3

Inject pathogen into a lab animal.

The animal makes antibodies in the blood for that pathogen.

You collect the antibodies from the blood.

You then use the antibodies in either:

1- ELISA (Enzyme linked immunosorbent assay) (if a well turns yellow it means the pathogen attached itself to the antibody - the pathogen is present)

Or

2- Lateral flow device (like a pregnancy test, two lines means the pathogen is present)

Question 4

What are the nucleic acid based techniques in Diagnostics?

Answer 4

1- PCR (need to know the gene of the disease to get primers for it) (open tube system so danger of contaminants and a lot of equipment)
2- Real time PCR (measures fluorescence of tubes) (closed tube system but a lot of equipment)
3- LAMP amplification (uses one temp, quick amplification time, closed tube system, portable machine)
4- Array technology (can scan the plant for a range of pathogens)
5- Biosensors (like an electronic nose - detects compounds given off in response to pathogen or from pathogen)