Comparison in purification methods of the recombinant human cardiac troponin I

Objective To compare the two kinds of purification method for purifying recombinant human cardiac troponin I (cTnI) to obtain the stable cTnI and promote the study of cTnI diagnosis standardization. Methods The cTnI inclusion body was obtained by the ultrasonic broken engineering, after washing by 2% Tritonx-100, 2M urea, dissolved in 8M urea, then purified by the column refolding on CM-FF and the dilution refolding respectively. The cTnI yields were compared between the two kinds of method and the stability at 4 [degrees]C ,20 [degrees]C, - 80 [degrees]C and on the freeze-dried condition was compared. Then the purification method to efficiently obtain the stable cTnI was established. Results The protein about 2 mg and 1.4 mg could be obtained by CM-FF on the column refolding and the dilution refolding from 0.1 g of wet inclusion body, respectively. The former method had the short cycle and high efficiency. The cTnI purified by the column refolding on CM-FF was more stable at 4 [degrees]C, 20 [degrees]C, -80