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Dear all,
I have one doubt, can we do serial dilutions for the prepartion of
calibration curve samples instead of spiking the drug to
individual samples.
For Ex: 100ul of plasma containing 10ug/ml of the drug, 50ul of
this(10ug/ml) will be diluted to 100ul with normal plasma to get
5ug/ml, 50ul of 5ug/ml will be diluted to 100ul with normal plasma
to get 2.5ug/ml and so on......... After this spiking internal
standard and extracting.
Is it acceptable?
Thanks,
B.L.Suresh
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Hello Suresh
No, this way you will transfer the error uniformly throughout. If you
really
want to do serial dilution then the best way is to prepare 3 sets from
three
intermediate stock solutions and prepare three separate dilutions (Say
series A1-A5, B1-B5 and C1-C5...). Then randomly pick up the tubes from
the
dilutions and then analyse. In this way the error will not be constant
but
more random which is essentially you quantify. This procedure will
require
more work!! You can then mix the remainder serum according to the
concentration to make more independent samples and then use them as
QC's.
Venkatesh Atul Bhattaram
Post-doctoral Fellow
University of Florida
Gainesville-32610
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All depends on the risk you are willing to accept. An alternative is to
prep two stocks then prep working standards A and B from the two stocks.
Points c, e etc are serially diluted from a while points d, f etc are
serially diluted from B.
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