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Peniel

Member Since 20 Feb 2013
Offline Last Active Yesterday, 08:57 AM

In Topic: Any tips on how to avoid lifting cells in 96well plates

24 April 2013 - 03:28 AM

Tom M, on 23 April 2013 - 01:11 PM, said:

We have a similar problem with HEK293 cells.  Using coated plates, poly-d-lysine or collagen for example, helps keep the cells attached.  In addition, we don't aspirate the media but rather invert the dish and gently pat the dish on an absorbent surface to remove buffer during the washing.

Good luck!

Thanks for the responses, I will try inverting them and patting on absorbent paper. Also putting the medium in slowly.

In Topic: Calculating Drug concentrations in Log scales

06 April 2013 - 02:45 AM

In Topic: Calculating Drug concentrations in Log scales

03 April 2013 - 02:12 PM

Tom M, on 03 April 2013 - 01:18 PM, said:

If you wish to run a curve between 100 nM to 10 uM and generate a "linear" log scale then try these concentrations:   100 nM, 300 nM, 1uM, 3uM and finally 10 uM.  That will yield values on the x-axis of (log molar) -7, -6.5, -6, -5.5, -5, -4.5; respectively.

Thank you so much Tom, I appreciate this. How does this relate to log10 values. One of my peers keep emphasizing 0.001, 0.01, 0.1, 1.0, 10, 100, 1000. Sorry this questions might seem stupid or basic but I have no clue.

Thanks

In Topic: Calculating Drug concentrations in Log scales

03 April 2013 - 11:30 AM

Peniel, on 03 April 2013 - 10:40 AM, said:

mdfenko, on 03 April 2013 - 06:48 AM, said:

log scales are 10-fold differences between doses.

you can do more than one dose within each log (eg 1, 2, 5, 7.5, 10, 20, 50, 75, 100, 200, 500, 750, ...)

Thanks mdfenko.

I don't know how to work this out. What I'm thinking is if my first concentration is 100nM then the log10 will be -7? Do I work then work from that in log scale i.e -6, -5, -3, -1, 0.01, 0.1, 1, 10.

I want to work within the range of 100nM to 10uM. Please I'll need some elementary explanation as I am rubbish at this.

thanks

I think I got that all wrong.
so for 1uM it'll be 0.01 in log scale. So I can do 0.01, 0.10, 0.30, 0.40, 0.50, 0.60, 0.65, 0.70, 0.80 and it will be equivalent to (uM) 1.02, 1.23, 1.995, 2.511, 3.162, 3.98, 4.67, 5.01, 6.31 and so on. Does this sound right?

In Topic: Calculating Drug concentrations in Log scales

03 April 2013 - 10:40 AM

mdfenko, on 03 April 2013 - 06:48 AM, said:

log scales are 10-fold differences between doses.

you can do more than one dose within each log (eg 1, 2, 5, 7.5, 10, 20, 50, 75, 100, 200, 500, 750, ...)

Thanks mdfenko.

I don't know how to work this out. What I'm thinking is if my first concentration is 100nM then the log10 will be -7? Do I work then work from that in log scale i.e -6, -5, -3, -1, 0.01, 0.1, 1, 10.

I want to work within the range of 100nM to 10uM. Please I'll need some elementary explanation as I am rubbish at this.

thanks