Determination of Organic Solvent in Radioactive Tracer ¹⁸FPBR06 Injection by Cold-on-Column Inlet Gas Chromatography

To develop a quality control inspection method for determining content of ethanol and residual solvent in radiolabeled tracer ¹⁸FPBR06 injection which is used for positron emission tomography imaging. Stabilwax CG column (30 m×0.52 mm, 1 μm) is selected. Temperature program: set initial temperature at 55 ℃, kept for 4 min, then increased to 200 ℃ at rate of 40 ℃/min, hold for 3 min. Hydrogen flame ionization detector is used and the temperature is 240 ℃. The carrier gas is high-purity nitrogen, and the inlet pressure is 5.5 psi (37.9 kPa). The temperature of Cold-on-Column inlet follows the column temperature. The results show that ethanol, acetonitrile, and DMSO have good linear relationships in the concentration range of 0.5%-12.0% (v·v^-1), 0.004 0%-0.048 0% (g·g^-1) and 0.025%-0.590% (g·g^-1). The limit of quantification (S/N=10) for ethanol, acetonitrile, and DMSO is 0.15% (v·v^-1), 0.002 9% (g·g^-1) and 0.008 2% (g·g^-1). The limits of detection (S/N=3) is 0.05% (v·v^-1), 0.000 87% (g·g^-1) and 0.002 5% (g·g^-1), respectively. The results of the standard addition recovery show that the method has good accuracy. The Cold-on-Column inlet GC method developed in this study is suitable for inspecting the content of ethanol, acetonitrile and DMSO in ¹⁸FPBR06 injection. The results of the method validation meet the requirements of the Chinese Pharmacopoeia 2020 edition. The method is accurate and time-saving, requiring only a small volume of sample, which is beneficial to improve the efficiency of product quality control inspection.