11 replies to this topic

[seanspotatobusiness]

For what would you say it's okay to use filterless tips and when would you says it's necessary to use tips with filters?

[pDNA]

i used filter tips just for qPCR ...but some people even use them for PCR ...it always depends how sensitive your assay is and if a false positve results needs to be absolutely avoided (e.g. in the testing of patient samples and so on).

If you just do an PCR screening i would not use filter tips ...but for qPCR we used to since the results got more reproducible.

Regards,
p

[Ameya P]

In my previous lab, we used non-filtered tips for everything.

However, here, we use filtered tips for PCR and non filtered for other things like loading gels. Since, we also isolate DNA from patient samples, we also use filtered tips for DNA isolation.

With experience and with the condition that you are the only one using the pipettes, I would say that you can phase out filtered tips over a period of time.

[chicken]

some times in our lab when shortage of filter tips,

i sterilize the nozzel of pippet with 70% ethanol, and it works well ,even i am working on cell cultures.

so whether u are with filtered or nonfiltered tips, it is u who knows how to protect ur experiment from contamination.

[Trof]

We use filtered generaly for all PCR, RNA and DNA isolation, everytime you need to protect the samples and chemicals from contamination and when we are pipetting bacteria to protect the pipette from contamination.

[Neanderthal]

I am using AXYgen filter tips for my RNA work. I am planning to reuse these tips for other purposes like cell culture etc (of course after washing/autoclaving/70% Ethanol application etc). But the problem is that I cant take out those filters from the tips. It is attached so tightly that I cant pull it out even with a needle. I have a good number of these tips and I don't feel like throwing them away just like that. I really want to save these tips.

Can anyone help me find an intelligent way to get the filters out of the filter tips?

Thanks
Neanderthal

[leelee]

I think re-using tips is a really bad idea. Especially given they aren't that expensive to buy (especially if you buy in bulk and rack them yourself).

If you are determined to reuse them- why do you need to take the filters out? You can just leave them in.

[Neanderthal]

leelee, on 15 November 2011 - 11:37 PM, said:

I think re-using tips is a really bad idea. Especially given they aren't that expensive to buy (especially if you buy in bulk and rack them yourself).

If you are determined to reuse them- why do you need to take the filters out? You can just leave them in.

Although I also do not like to re-use tips, I do not want to waste these resources if there is any chance that I can use them again. Removing filter is essential because if at all I can use it for cell culture, I need these tips to connect to vacuum tubing to suck out medium, PBS etc ( I am having a little technical difficulties with the vacuum pump here, so I need to connect a tip to the end of tubing). If there is filter, then the whole purpose of re-using  tips is defeated.

Moreover, if there are no filters, then it will be easier to wash/autoclave these tips in bulk. It is hard to clean/wash  tips with filters ( I may have to pipette it up and down several times, each tip individually to do so).

Thanks
Neanderthal.

Edited by Neanderthal, 16 November 2011 - 12:08 AM.

[leelee]

Fair enough. Can't help you on how to get the filters out sorry, I did try once before (for the same reason as you, to use with vacuum) but failed.
You can still vacuum through the filter, but its really slow.

[Neanderthal]

leelee, on 16 November 2011 - 01:35 AM, said:

Fair enough. Can't help you on how to get the filters out sorry, I did try once before (for the same reason as you, to use with vacuum) but failed.
You can still vacuum through the filter, but its really slow.

Thanks for sharing leelee.

Any one else want to try?

[bob1]

We used to use glass pasteur pipettes as tips for vacuum lines in cell culture, they can be easily washed and re-used if necessary.

Don't re-use the filter tips, they are designed to be single use only, so you won't be able to remove the filter.  Especially don't re-use them for PCR or cell culture, this is the reason that HeLa makes up about 30% of current cell lines...

Edited by bob1, 16 November 2011 - 02:29 PM.

[Neanderthal]

bob1, on 16 November 2011 - 02:27 PM, said:

We used to use glass pasteur pipettes as tips for vacuum lines in cell culture, they can be easily washed and re-used if necessary.

Don't re-use the filter tips, they are designed to be single use only, so you won't be able to remove the filter.  Especially don't re-use them for PCR or cell culture, this is the reason that HeLa makes up about 30% of current cell lines...

OK..so most people are against the idea of reusing filter tips. Good to know..

Thanks a lot!!