提高过滤浓缩阶段对两虫回收率的试验研究

针对美国EPA1623检测方法中过滤浓缩、免疫磁分离和荧光免疫镜检这3个主要步骤进行了分段回收率的研究。结果表明,过滤浓缩为导致两虫回收率损失的关键步骤,因此对过滤浓缩中的洗脱和分离过程进行了相应的改进和替代。以超声洗脱替代振荡洗脱,用滤膜抽滤/超声洗脱替代离心分离,构成优化的过滤浓缩工艺,具有较高的回收率,操作简单且成本较低。其对卵囊和孢囊的初始回收率分别为61%和55%,远高于EPA1623方法的最低要求,适宜作为国内自来水厂的常规检测方法。

Improvement of Cryptosporidium and Giardia Recovery in Filtration and Concentration Stages

The three main steps of USEPA1623, filtration and concentration, immunomagnetic separation and immunofluorescent microscopy were analyzed to investigate the recovery rates of Cryptospo-ridium and Giardia. The filtration and concentration are key steps induce to the recovery loss, and the appropriate improvement and replacement during elution and separation were carried out. Using ultrasonic elution to replace oscillation and membrane filtration plus ultrasonic elution to replace centrifugal separa-tion compose a optimized filtration and concentration process which has high recovery rate, simple opera-tion and low cost. The initial recovery rates of oocysts and cysts are 61% and 55% respectively, which are much higher than the minimum requirement of EPA1623 method. The new method can be used as a conventional detection method in China.