目的  建立白喉-破伤风-无细胞百日咳疫苗生产中百日咳毒素（pertussis toxin, PT）含量的测定方法。方法  免疫家兔制备高效价抗PT血清，纯化抗PT多克隆抗体并进行酶标记，建立双抗体夹心ELISA法并对其进行验证。结果  建立的方法在0~20 ng/ml PT测量区间呈现最佳线性，相关系数＞0.99，且重复性好。检测百日咳丝状血凝素和黏着素，结果均为阴性，说明该法特异性良好。试验内10次、不同试验间3次测定16.0、8.0、4.0、3.0 ng/ml PT，变异系数为2.8%~9.7%，回收率为95.7%~106.0%，精密度和准确度验证均符合常规质量控制要求，定量限度为3.0 ng/ml。结论  该方法能有效检测百日咳杆菌大罐发酵过程中分泌的PT，为PT质量控制奠定了重要基础。

Objective  To develop an ELISA method for quantitative determination of pertussis toxin (PT) during production of combined diphtheria, tetanus and acellular pertussis vaccine.  Methods  After chinchilla rabbits were immunized by PT, high titer anti-serum against PT was obtained and polyclonal antibody against PT was prepared. Then, a double antibody sandwich ELISA method was developed and verified.  Results The best linearity ranged from 0 to 20 ng/ml of PT (r＞0.99). No cross reactions with filamentous hemagglutinin and pertactin were observed by the developed ELISA. The variation coefficients of intra- and inter-assays were 2.8%-9.7% and the recovery rates were 95.7%-106.0% when 16.0, 8.0, 4.0 and 3.0 ng/ml of standard PTs were determined. The quantitative limit was identified as 3 ng/ml.  Conclusion  Due to the excellent specificity, precision, and accuracy, this method can be applied to detecting PT in fermentation broth quantitatively.