To study on the influence of residual liquid left on the aspirating needle of automatic Western Blot instrument on HIV Confirmation

Objective To study the influence of residual liquid left on the aspirating needle of automatic western blot instrument on HIV confirmation, to find out the contamination process and eliminate experimental methods which may cause cross contamination. Methods Using a pipettorto absorb reaction liquid which was simulated as residual liquid left on the aspirating needle of automatic western blot instrument. Then the reaction liquid was added into new reaction system to test whether the result was abnormal or not. Results If any HIV specificity stripe appears on a reagent strip without HIV samples in a test, it was considered to be contaminated. When experimenters had changed suction head to absorb reaction liquid before each test, it was found that no stripe appeared, which means no cross contamination happened. Conclusions The factor most likely to cause contamination is found out by tests. Using appropriate liquid absorption method is an effective way to prevent contamination and to make test results of automatic western blot instrument more accurate and reliable. Key words: Aspirating needle; Residual liquid; Cross contamination