nonspecific binding is higher than total binding in radioligand binding assay, W - (Dec/28/2009 )

when performed receptor binding assay using astrocyte cell pellet and 3H-DPCPX, i chose CPA as the displacer. and then the nonspecific binding is about 80% of the total.

it happened 3 times, so i thought maybe the CPA concentration was not high enough. so i did 9 different concentration of CPA (from the highest permitted solubility, 10 time gradient dilution), and used the fixed concentration of 3H-DPCPX. but the nonspecific binding was still about 80%-120% of the total.

i would highly appreciate your insights!!
and happy holiday!

Can you please clarify (name and structure)

3H-DPCPX

and

CPA

thank you.

sure! and thanks for your reply.

3H-DPCPX is a radioactive ligand, with a structure can be found in the following link:
http://www.iuphar-db.org/DATABASE/LigandDi...rd?ligandId=386

CPA(N6-Cyclopentyladenosine) is used as the displacer to cover all the non-specific binding from A1R in this experiment. the structure of CPA can be found here:

http://www.sigmaaldrich.com/catalog/Produc..._KEY&F=SPEC

or:

http://www.iuphar-db.org/DATABASE/LigandDi...rd?ligandId=435

sgt4boston on Jan 7 2010, 03:13 PM said: