GENERAL TREATMENT OF COMPETITIVE-BINDING AS APPLIED TO THE POTENTIOMETRIC ION PROBE TECHNIQUE - APPLICATION TO THE INTERACTION OF NONSTEROIDAL ANTIINFLAMMATORY DRUGS WITH BOVINE SERUM-ALBUMIN
At. Angelakou et al., GENERAL TREATMENT OF COMPETITIVE-BINDING AS APPLIED TO THE POTENTIOMETRIC ION PROBE TECHNIQUE - APPLICATION TO THE INTERACTION OF NONSTEROIDAL ANTIINFLAMMATORY DRUGS WITH BOVINE SERUM-ALBUMIN, Journal of pharmaceutical sciences, 83(8), 1994, pp. 1150-1154
The binding of naproxen, ketoprofen, phenylbutazone, salicyclic acid,
azapropazone, and indobufen to bovine serum albumin was studied by app
lying the potentiometric ion probe technique. An ion-selective electro
de for the ion probe 1-anilino-8-naphthalenesulfonate was utilized for
the purposes of this study. A modified site-oriented competitive bind
ing model was used for the estimation of the drugs' binding parameters
, considering different number of binding sites on the competing bindi
ng class(es) for the probe and the drug. Calculations v,ere based excl
usively on the concentration data of the free probe. The model's abili
ty for accurate estimations of binding parameters was evaluated by sim
ulation studies. The following values of binding parameters were found
at 25 degrees C for the drugs under study; naproxen, n(1) = 9.1, k(1)
= 9.4 X 10(5) M(-1); ketoprofen, n(1) = 8.8, k(1) = 10.8 X 10(5) M(-1
); phenylbutazone, n(1) = 3.2, k(1) = 1.4 X 10(5) M(-1); salicylic aci
d, n(1) = 2.6, k(1) = 1.8 X 10(5) M(-1), n(2) = 21.5, k(2) = 1.0 X 10(
4) M(-1); azapropazone, n(1) = 0.5, k(1) = 7.8 X 10(5) M(-1), n(2) = 2
6.3, k(2) = 1.9 X 10(4) M(-1); indobufen, n(1) = 5.8, k(1) = 5.8 X 10(
5) M(-1), n(2) = 19.9, k(2) = 3.8 X 10(5) M(-1), where n(i) the number
of binding sites of the i class and k(i) the corresponding associatio
n constant.