The following points must be dealt with on ELISA operation:
1） Only the disposable tips can be used for the experiments and the tips must be changed when used for different reagents.
2） Before the experiment, each experimental equipment must be clean and should be re-cleaned if necessary, in order to avoid the contamination that interferes with the experimental results.
3） The room temperature below 20 ℃ or the temperature of the reagents and the samples being not returned to the room temperature (20-25 ℃) will lead to a lower standard OD value;
4） Dryness of the microplate in the washing process will be accompanied by the situations
5） including the non-linear standard curves and the undesirable reproducibility;
6） Mix every reagent and reaction mixture evenly and wash the microplate thoroughly, otherwise there will be the undesirable reproducibility;
7） The stop solution is the 2 M sulfuric acid solution, avoid contacting with the skin;
8） Put the unused microplate into an auto-sealing bag to re-seal it. The standard substance and the colourless color former is light sensitive, and thus they cannot be directly exposed to the light;
9） Do not use the kit exceeding its expiry date. The use of diluted or adulterated reagents from the kits will lead to the changes in the sensitivity and the detecting OD values. Do not exchange the reagents from the kits of different lot numbers to use;
10） Discard the colouration solution with any color that indicates the degeneration of this solution. The detecting value of standard solution 1（0 ppb） of less than 0.5 indicates its degeneration;
11） Colouration time is 15 min after the addition of the substrate A and then the B solution, if the color is light, prolong the time, don’t exceed 30min;
12） The optimum reaction temperature is 37 ℃, and too high or too low temperatures will result in the changes in the detecting sensitivity and OD values.