Charge Transfer Reaction Between L-Threonine and Tetrachloro-p-Benzoquinone

In a borate buffer solution of pH 9.0,charge-transfer reaction between L-threonine and tetrachloro-p-benzoquinone was observed,and the complex formed had its absorption maxima at the wavelength of 220.3 nm and the value of its apparent molar absorptivity of 5.9×105L·mol-1·cm-1.Beer′s law was obeyed in the range of 0.39-1.94 mg·L-1 of L-threonine.This method was applied to the determination of L-threonine in samples of injection liquor,giving results in consistency with the results obtained by method in pharmacopoeia,and the value of RSD′s (n=9) found was less than 1%.Results of recovery test obtained by standard addition method were in the range of 99.8%-100.3%.