to determine the presence of colophonium in the samples, the sample components are often derivatised and separated by gas chromatography (gc) [2, 6, 8-10, 13, 21-23] or separated by high-performance liquid chromatography (hplc) in their unmodified form [3-5, 8, 12, 13].

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To determine the presence of colophonium in the samples, the sample components are often derivatised and separated by gas chromatography (GC) [2, 6, 8-10, 13, 21-23] or separated by high-performance liquid chromatography (HPLC) in their unmodified form [3-5, 8, 12, 13].