BioSemi.nl

Hello

I'm using the ActiveTwo2 system, and I wonder how long does a set of electrodes usually last?
I think our lab purchased these sets 5-6 years ago.

The older sets last 100-200 measurements. The new sets with red rubber strain reliefs should last considerably longer. On a mechanical test rig, the new sets sustained 5 to 10 times a much bending actions before the conducting core broke. However, since we are distributing the "rubberrized" sets only since November 2015, we cannot yet say how exactly this will translate into longer lifetime in practice (although not a single defect was reported yet, so things look good). With the new sets, the limiting factor will probably be the slow deterioration of the silver-silverchloride tip due to pollution with non-silver metal particles (increased noise, baseline drift and offset).

When stored in a dark environment (to prevent deterioration of the Ag-AgCl tips by UV light), the sets should have a shelf-life of at least 5 years.

Best regards, Coen

Hi,
I'd like to reply on the above, although it's quite an old message.
I'm in a new lab, and there are a few bundles that various groups use, and nobody really seems to know how often they were used and how old they are...
In my previous lab every group had its own bundle, and we marked the bundles and renewed after 200 measurements. So I'm trying to figure out what people recommend but there isn't much out there on the web.
In your post you replied that "older sets last 100-200 measurements". What is older in this case?
And, is there a good, reliable way to actually measure the data quality of the electrodes, some sort of signal to noise ratio?
I need to give my boss good reasons to buy a new set
Thanks,
Joram

Test the electrodes in salt water as described on http://www.biosemi.com/faq/check_electrodes.htm

Noise should not be much higher than approx. 5 uV peak-to-peak (referenced to the average of all electrodes, 100 Hz low pass), offsets should be stable and within approx. +50 mV and - 50 mV.

Best Regards, Coen