The enzyme-linked immunosorbent assay using the "indirect" method in micro-scale was applied to determine the type F toxin of $\underline{Clostridium} \underline{botulinum}$. The absorbance profiles of four different combinations of anti-botulinum serum and conjugate were compared each other. Three different concentrations of Tween 20 in diluent (0.05, 0.1, and 0.2%) were examined to search the optimal condition. The change of concentration of Tween 20 in diluent did not affect significantly the absorbance profile beside the combination of horse anti-botulinum serum as bridging antibody and rabbit conjugate. The minimum dectectabe dose of type F toxin by "indirect" ELISA was found to be 10 mouse ip $LD_{50}$ and the quantitative assay was also possible.
For the quantitative assay in range of $10^2$ to $10^4$ mouse ip $LD_{50}$ dose of type F toxin, two combinations in which mouse antiserum rabbit antiserum was used as bridging antibody were suitable for "indirect" ELISA.
But the combination which showed the linear increment of absorbance over full range tested (10 to $10^4$ mouse ip $LD_{50}$), was that of horse anti-botulinum serum as bridging antibody.
$\underline{Clostridium} \underline{botulinum}$ type F, Strain Langeland의 독소를 microtiter plate 상에서 간단히 검출 할 수 있는 면역학적 효소 방법을 연구하였다.
방법은 다음과 같다.
(1) 각기 다른 양의 botulinum type F 독소를 polystylene microtiter plate에 부착
(2) 네 가지 종의 anti-type F serum 을 가함.
(3) 각 종에 대한 anti-species IgG-HRPO conjugate를 가함.
(4) HRPO에 대한 기질 가함.
(5) 반은 정지시키고, A(492nm) 기록.
독소의 검출한계는 약 10 mouse ip $LD_{50}$였으며, 독소의 정량적 검출이 가능했다. 희석용액내의 세척제 (Tween 20) 농도 변화는 검출 감도에 큰 영향을 주지 않았다.
