Kitagawa T, Kanamaru T, Wakamatsu H, Kato H, Yano S, Asanuma Y
J Biochem. 1978 Aug;84(2):491-4. doi: 10.1093/oxfordjournals.jbchem.a132151.
A new method for the preparation of ampicillin-BSA conjugate by a three step procedure was developed. The first step is the introduction of a maleimide residue to ampicillin by a cross-linking reagent, MBS. The second step is reductive cleavage of disulfide bonds in BSA. The third step is thioether formation between the introduced maleimide residues and the reduced thiol groups. The obtained ampicillin-BSA conjugated raised an anti-ampicillin serum in rabbits. A new reagent, MPGS, was used for enzyme labelling of ampicillin to avoid immunological cross reaction. Using the enzyme labelled ampicillin and anti-ampicillin serum, enzyme immunoassay of ampicillin was successful in detecting 4 ng to 1 mug. Cross reactivities of anti-ampicillin to ampicillin analogs were studied by the enzyme immunoassay to find that the antiserum is specific to penicillin especially to ampicillin but hardly reacts with cephalosporins or the penicilloic acid derivative of ampicillin.
开发了一种通过三步法制备氨苄青霉素 - 牛血清白蛋白（BSA）偶联物的新方法。第一步是通过交联剂MBS将马来酰亚胺残基引入氨苄青霉素。第二步是还原裂解BSA中的二硫键。第三步是在引入的马来酰亚胺残基与还原的巯基之间形成硫醚。所获得的氨苄青霉素 - BSA偶联物在兔体内引发了抗氨苄青霉素血清。一种新试剂MPGS用于氨苄青霉素的酶标记以避免免疫交叉反应。使用酶标记的氨苄青霉素和抗氨苄青霉素血清，氨苄青霉素的酶免疫测定成功检测到4 ng至1μg。通过酶免疫测定研究了抗氨苄青霉素对氨苄青霉素类似物的交叉反应性，发现抗血清对青霉素特别是氨苄青霉素具有特异性，但几乎不与头孢菌素或氨苄青霉素的青霉酸衍生物反应。
