Patent ID: 7943117

Claim:
A method for testing radiochemical purity of Tc-99m-TRODAT-1, comprising steps of: (A) obtaining a Tc-99m-TRODAT-1 solution as a sample; and (B) processing an test through a high performance liquid chromatography (HPLC), said HPLC comprising steps of: (I) delivering an eluent into a chromatography column under a certain speed by using a high pressure pump; (II) injecting an amount of sample into said chromatography column by using an injector; (II) eluting said chromatography column by using said eluent to process a separation of said sample to elute outcomes from said chromatography column sequentially; and (IV) processing said chromatography column with a detector to obtain a chromatography, wherein said eluent is obtained by mixing acetonitrile and 5 millimolars of 3,3-dimethylglutaric acid (DMGA) with a pH value of 7; wherein said eluent is delivered to said chromatography column in a speed between 0.5 milliliters per minute (ml/min) and 3 ml/min; wherein said chromatography column is a C-18 column; wherein said sample is injected into said chromatography column in an amount between 0.5 microliters (μl and 3 μl; and wherein said detector is a radio-detector; wherein the said chromatography results in a separation of two diastereomer peaks; the resolution (Rs) of the first diastereomer peak to the impurity is 11.548, 11.523, 12.531, 12.787 14.308, 11.100, 10.153, 9.125, or 11.457; the resolution (Rs) of the second diastereomer peak to the impurity is 4.854, 4.654, 4.475, 4.564, 5.023, 4.524, 4.423, or 4.611; and the tailing coefficient for the first peak is 1.213 and the tailing coefficient for the second peak is 1.043.