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Archive for the ‘cell culture’ Category

Cell passaging video

In cell culture, iGEM, Lab equipment, molecular biology, Resources, sterile, video on March 9, 2011 at 9:48 pm

We think videos can help a lot for newcommers into the molecular biology laboratory.

One of the goals of our team (iGEM Debrecen 2010) was to generate high quality videos of basic lab protocols. All the protocolls can be viewed here but you can have an intro into Cell passaging righ now if you watch this video:

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Hunting Viruses

In cell culture, DNA, molecular biology, RNA, virus on March 30, 2009 at 6:02 pm

If it comes to speak about the future possibilities of molecular biology, it is worth keeping an eye on the medical applications. And if you think about the most peculiar infection agents you should for sure think of viruses also. What is a virus? Of course we all know what a virus might cause to us, like a simple respiratory infection. These are usually caused by viral infections that later are super infected with bacteria. I had a professor who tried to explain us what a virus is. It skips almost any definitions. We can not be sure if we could consider a living thing at all!!! At the end he told us in a laconic way: a virus is a VIRUS! Nothing more.

If we try to find them it is good to know, that they were discovered through the observation that you can transfer an infection from one cell culture to the other even after filtrating the solution through a filter with 0.4 micrometer holes. That means that no bacteria can bypass this filter, but infections can be transferred with this solution. The firs experiments were done in order to monitor these infections, to see that after infection there was a “clean window period”, a period when the infections agent disappeared from the cell culture. After this window the virus reappeared and the supernatant solution had infections properties again.

Today we know plenty of details about viruses. There are basically two flavours of them DNA and RNA viruses. So that is an important point! because we have plenty of molecular biology tools that allow us to characterize nucleic acids. One of the most complex tool from this series is the DNA microarray. As one of my students pointed out last week, in the next video from TED, we can have a wonderful presentation about how these tools can be used in a fast and relatively easy way to get a deeper insight in the world of viruses. As a perspective the video shows us some excellent diagnostic applications that will be probably used to develop state of the art diagnostic tools in the next couple of years.

So, let us see how it works!

More info about the viruses and vaccination, here.

Using Serological Pipettes

In cell culture, Lab equipment, molecular biology, Pipet, sterile on March 2, 2009 at 2:07 pm
Dear Colleagues,
I promised you to give an update about serological pipettes.
We use serological pipettes when we want to manipulate (to move) liquids that are in the range of 5 to 25 ml. Smaller volumes than 5ml can be measured with Gilson type pipettes, while for larger volumes than 25ml we use measuring cylinders.
Serological pipettes have a dispensable graduated tube, and a filter that is not allowing contamination with any particles from the air. The pipettes look like this for example:
serological-pipette

serological-pipette

They can be charged, have a button to move liquids up and one for release the aspirated liquids.

We use sterile, single packed pipettes in three different ranges: up to 5ml, to 10ml and to 25ml. They have different color codes:

sterile-serological-pipettes

sterile-serological-pipettes

The same from their back:

back-of-the-sterile-serological-pipets

Please have a look to my demo of how to use them:

Settings of a typical serological pipette can be seen below. You can adjust the power of the pump that enables you to move volumes as small as 1/10 of ml. And you can switch between “drop wise” and “blow out” mode. You use “drop wise” mode when you do not want to disturb the cells on the bottom of a culturing dish.

head-of-serological-pipette

head-of-serological-pipette

A detailed demo about serological and other similar type of pipettes:

What about using Gilson type pipettes in the cell culture lab? We have sterile, pyrogenic free tips for the cell culture lab. This box contains for example certified DNAse, RNase and Pyrogen free tips. Each tip has an individual filter insert! You can use them for probably any protocoll in a standard molecular biology lab. Don’t forget, they are not cheap at all…

barrier-tip-box-1ml

barrier-tip-box-1ml

barrier-tip-1ml

barrier-tip-1ml

Smaller volumes can be measured with smaller barrier tips:

barrier-tip-10ul

barrier-tip-10ul

I think we should go to the cell culture lab in one of our next post!

That’s all for today, and let me have your feedback!

Plenty of good basic info regarding laboratory work is described <a href="”>here.

Cheers,

Balint.