Biology-Online • View topic - Finding Final concentration after dilutions
Login

Join for Free!
121815 members
Advertisement
Advertisement

Finding Final concentration after dilutions

Discussion of all aspects of biological molecules, biochemical processes and laboratory procedures in the field.

Moderator: BioTeam

Finding Final concentration after dilutions

Postby FireWarden » Wed Feb 10, 2010 9:44 pm

Hi. Ive been trying to figure this out but havent been able to get a concrete way of doing this.

I have a stock solution of 50pg/ml. The stock solution is diluted a number of times:

Dilution of stock
0.0001
0.001
0.01
0.1
0.1
0.5
0.5
1

Volume of Diluted stock taken
7.5[µL]
7.5
7.5
7.5
75
75
175
175

*the two lists should be beside each other and the rows should match...each row would basically be a well and a point on a graph*

Then a volume of this stock (noted above) is taken in microlitres, added to an ELISA reaction which has a total volume of 200 [µL]. The aim of this question is to make a standard curve blah blah...i dont need help with that. I need help in calc the final concentration for the stock after the Stock has been diluted and taken with the volume indicated.

I know I have to use C1 x V1= C2 x V2......C1 is the diluted concentration and V1 is the volume of diluted stock take...right?

C2 is what I need and V2 is the 200 [µL]...correct?

So its simple algebra. Where I am getting confused is whether or not I should convert the stock 50picograms/ml to 50 picograms/ [µL]....so that all the units are the same...or does that matter?

Can i just go.....50pg/ml x 0.0001= C1
and 7.5 [µL] =V1

and go on from there for each one to make my points on the curve? Any help with be great.
FireWarden
Garter
Garter
 
Posts: 2
Joined: Wed Feb 10, 2010 9:17 pm

Postby JackBean » Wed Feb 10, 2010 9:53 pm

how can you get different dilution, when using the same volume?
http://www.biolib.cz/en/main/

Cis or trans? That's what matters.
User avatar
JackBean
Inland Taipan
Inland Taipan
 
Posts: 5694
Joined: Mon Sep 14, 2009 7:12 pm

Postby FireWarden » Wed Feb 10, 2010 10:05 pm

I am not sure I understand your question...try to think of each row as a well...

so for the first well...

1.Dilution of the 50 pg/ml stock is 0.0001 and the volume of stock is 7.5 mirolitres
2. dilution of the 50 pg/ml stock is 0.001 and the volume of stock is again 7.5 microlitres

...this is done for each row. I am looking for the C2 for each of those rows.
FireWarden
Garter
Garter
 
Posts: 2
Joined: Wed Feb 10, 2010 9:17 pm


Postby JackBean » Thu Feb 11, 2010 12:10 pm

OK, forget now about some dilutions.

Your original concentration is 50pg/ml in this volume:
Volume of Diluted stock taken
7.5[µL]
7.5
7.5
7.5
75
75
175
175

into final volume of 200 ul, right?
Than you have to get the same contcentration in first four wells
http://www.biolib.cz/en/main/

Cis or trans? That's what matters.
User avatar
JackBean
Inland Taipan
Inland Taipan
 
Posts: 5694
Joined: Mon Sep 14, 2009 7:12 pm


Return to Molecular Biology

Who is online

Users browsing this forum: No registered users and 0 guests