Tuesday, October 16, 2007

A morning in the laboratory.

It is so good to meet someone who is enthusiastic about what they do and yesterday I met a couple of virologists at a nearby hospital who really love their subject - and I could see why; it is fascinating.

A group of nurses were being shown around and I went along too. Their job is to extract blood from drug-users to test them for diseases including hepatisis A, B and C, AIDS and syphilis.

The laboratories we saw were highly automated. Great banks of machines are fed by workers dressed in the pale blue lab coats of the bioscientist. Trays are filled with tiny sample bottles and then the lids closed and the whole thing is left to go. There is a quiet hum and robotic arms shift, lift and sample. Everything seems relaxed and organised. I saw only about ten laboratory workers and yet they handle thousands of samples each week. It is one of the largest virology labs in the world.

Each incoming sample is is labelled and logged on the computer so its progress can be followed. It is then fed into a sampling machine and robotic arms inject tiny beads which are impregnated with suitable antibodies. Any virus in the samples then reacts and sticks to the bead. The beads are then held by a magnet and washed and then tagged with another antibody which fluoresces in ultra-violet light. The greater the amount of light the greater the concentration of virus in the sample.

Another technique we saw used the polymerise chain reaction (PCR) in which the DNA or RNA from a particular virus is amplified using a repetitive cyclic reaction. The cells in the sample are first 'opened' so that the RNA and DNA of the virus is exposed. This sample is then added to a fluorescent enzyme which will only bind to a full length of the RNA of, say, hepatitis C. This allows selective replication of the RNA. The solution is then heated to 95 degrees C which causes the strands to separate so that with more enzyme the replication process can then occur again. In the first cycle the quantity doubles, in the next it doubles again until, by cycle 20 there may be enough fluorescent RNA to be seen in the light detector.

Maybe I am strange but I found this really exciting. It means that if you have a sample you are desperate to analyse you can stand over the machine and see exactly how much virus there is in a sample just by watching when the light is emitted.

Then we saw the cold rooms and autoclaves, the category III laboratory where dangerous diseases are handled in low pressure rooms (so if there is a leak air goes in rather than out) and there are gloves boxes and air trap entrances.

I came away determined to find out more...and of course have ordered a few more books for my research. I feel a new obsession coming on.


Blogger Susangalique said...

this sounds really interesting, you are going to be knowing all kinds of new things.

Tue Oct 16, 11:08:00 pm  
Anonymous Clare said...

Thanks S. It is facinating, and I want to do it but don't know if I can now...

Fri Oct 19, 08:39:00 am  
Blogger Lee said...

FAscinating, please keep reporting!

Fri Oct 19, 09:55:00 am  
Anonymous marly said...

Ah, a new obsession. Delicious!

Fri Oct 19, 03:55:00 pm  
Anonymous Clare said...

Yes, I have today decided that the obsession will be allowed to continue unrestrained...

Fri Oct 19, 10:32:00 pm  

Post a Comment

Comments are subject to moderation.

<< Home