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another dilution question - urgent (Jul/26/2010 )

I have a sample that needs to be diluted 1:10. To make the 1:10 dilution, I take 1ul from sample and add it into 9ul water.

Next, I have to make a 1:75 dilutions from the 1:10 at final volume of at least 60ul. Are my dilutions correct? Is it the right way to do this?

make 1:20 dilution from 1:10 = 10ul from 1:10 into 10ul water
make 1:50 dilution from 1:20 = 20ul from 1:20 into 30ul water
make 1:75 dilution from 1:50 = 50ul from 1:50 into 25ul water
split the 1:75 dilution into 3 tubes of 20ul each

Can I dilute directly from 1:10 to make 1:75 at 60ul final volume, and how?

How to make 80ul final volume of 1:75 from 1:10?

-claritylight-

claritylight on Mon Jul 26 10:25:10 2010 said:


I have a sample that needs to be diluted 1:10. To make the 1:10 dilution, I take 1ul from sample and add it into 9ul water.

Next, I have to make a 1:75 dilutions from the 1:10 at final volume of at least 60ul. Are my dilutions correct? Is it the right way to do this?

make 1:20 dilution from 1:10 = 10ul from 1:10 into 10ul water
make 1:50 dilution from 1:20 = 20ul from 1:20 into 30ul water
make 1:75 dilution from 1:50 = 50ul from 1:50 into 25ul water
split the 1:75 dilution into 3 tubes of 20ul each

Can I dilute directly from 1:10 to make 1:75 at 60ul final volume, and how?

How to make 80ul final volume of 1:75 from 1:10?


8 mcl from 1:10 and 52 mcl diluent will give u 1:75 directly
10.66 mcl from 1:10 and rest make upto 80 mcl with ur diluent...

u have 1:10 already.. to make it 1:75 u need to dilute it 7.5 times more (10X7.5=75)
final volume is 60 or 80. so just divide the final volume by the dilution factor and u get the volume to be aliquoted from the stock!!!

-Prep!-

diluting is ...x...

if you dilute 10 time the first time and 2 times the second time then the total dilution is 20times.


If you have a sample that is diluted 10 times and you need it to be 75 times, then just make a new dilution of 7.5 times.

Ex: 1Ál of your sample with 6.5 of water.
Or to have more volume (more then 60): 10Ál with 65Ál...

Or to have a bit over 80: 10Ál + 65Ál + 1Ál + 6.5Ál (a bit over 80, so better to disperse over some vials.

your method is ok, but its too much work to be honest.

-pito-

Can someone just correct these also? They are different variations (different final volumes)

Again these dilutions all come from previously diluted 1:10 samples.

To make
1:75
10ul of 1:10 + 65ul of water
3ul of 1:10 + 22.5ul water
1ul of 1:10 + 6.5ul water

To make
1:15
10ul of 1:10 + 5ul water
2ul of 1:10 + 1ul of water

To make
1:20.
10ul of 1:10 + 10ul water
1ul of 1:10 + 1ul water

To make
1:100.
10ul of 1:10 + 90ul water
1ul of 1:10 + 9ul water

-claritylight-

1/75 are ok

1/100 also

1/20 also ok

1/15 also

-pito-