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autoclaving tubes for PCR/RT-PCR - (Mar/01/2007 )


some time ago i began to think about why we autoclave tubes before using them. I mean, they are specified as RNAse and DNAse and DNA free, so is it really a good idea to put them in the probably not RNAse and DNAse and DNA free auotoclave or is this necessary, especially for RNA working? I use sterile filter tips for RNA working, but we do not have sterile tubes. (I mean, if the tubes were really free of any RNAses and DNAses they have to be sterile, because any organism contains these enzymes).

I am not talking of work with bacterial cultures, only of work with RNA or DNA.

I'm wondering if i do more good ore more harm by autoclaving them.

Thank you in advance for your opinion



I agree - if the tubes are clean, they'd have to be sterile. I stopped autoclaving my PCR tubes a while ago under this logic. Of course it is a leap of faith to assume that the tubes purchased as RNase/Dnase free actually are, but I've not had problems as long as their bags are stored in a clean environment and opened onto a Rnase-away treated surface while wearing gloves.


I dont bother autoclaving them for DNA/RNA work - The tubes I use are pyrogen, DNAse and RNAse free and I my experience, I have never had any problems. You can get little bags of 50 tubes for RNA work - open a new bag every time and use the ones you have left for something else.

I was once told that autoclaving can introduce RNAse into the tubes, although to be honest, I don't know how you'd check this.


Autoclaving does not destroy RNAses, so if (by accident) the user before somehow contaminated your autoclave with RNAses yoou might get into trouble.
I wouldn't autoclave them if you buy them pyrogen,dnase,rnase free.


You are right about autoclaving wouldnt really destroy RNases. But i guess even though some packets claimed to be dnase or rnase free, after autoclaving, some people might think it is much safer and cleaner and more confident to use. Mindset really. There were some cases whereby I have to use UN autoclaved tubes cause I had finished my autoclaved one. So I went to use the non autoclaved. And nothing really happened. Still the same. I guess after all, it is ok not to autoclave tubes. wink.gif


Well it depends how many people used them and if they practice good laboratory procedures. In past I seen so much mistakes...then they curse because of get contamination, as possible I prefer to have my own pack of tubes and pipet tips...but not always is possible...So I just put them under UV...just in case that the person before me sneeze over them dry.gif . The only ones that I don't put under uv are the caps for QPCR apparently they change color (that's what I had been told).