Development of liquid gene chip technique for detecting Toxoplasma gondii and Trichinella spiralis in food.

A duplex PCR based on liquid gene chip technique for detecting Toxoplasma gondii and Trichinella spiralis in foods was developed using primers designed according to the T.gondii B1 and T.spiralis 18S rDNA gene sequences,respectively.The amplified B1 and 18S rDNA PCR fragments were 188 bp and 92 bp in length,had 99.47% and 100% identities to the corresponding sequences in GenBank.The liquid chip was able to detect both single and duplex PCR products from the targets with high specificity and reproducibility.The detection limit of the assay was 65.6 ng/mL for T.gondii and 39.06 ng/mL for T.spiralis,which was 8-fold more sensitive than that of agarose gel method.The simulation of pollution test showed that the accuracy rate of blind test was more than 98%.The results showed that liquid gene chip technique was a rapid,sensitive and specific method for detecting T.gondii and T.spiralis in food.