Non-polar benzotriazoles, commonly known as benzotriazole UV stabilizers, are capable of absorbing radiation in a broad UV spectrum, making them extremely important industrial chemicals. In recent decades, the use of non-polar benzotriazoles has increased in all parts of the world, they are frequently found in shampoo, toothpaste, hair dyes, nail polish, make-up, contact lenses and similar products. Their widespread use as a result of anthropogenic activity leads to a proven accumulation in the environment. Elevated levels have been found in a wide range of marine and coastal organisms around the world, as well as in water and sediment samples.
In my diploma thesis I concentrated on the verification of the methods developed so far for the determination of nonpolar benzotriazoles. In the experimental part I optimized the conditions for the separation on a high performance liquid chromatography column with a diode array detector.
In the methods developed so far, solid phase extraction predominates as an extraction technique for the analysis of liquid samples. The use of sorptive stirred rod extraction, solid-phase microextraction and liquid-liquid extraction with a funnel separator is also frequently observed. Among the extraction techniques for the analysis of sediments and biological samples, Soxhlet extraction predominates. Pressure liquid extraction, ultrasonic extraction, high speed solvent extraction, "shaking" extraction and microwave assisted extraction were also used. The separation of individual chemical species is usually performed on GC or HPLC columns and their modifications, coupled with MS or MS /MS detector.
In the experimental part I successfully optimized the gradient of the mobile phase, resulting in sharp and well separated chromatographic peaks with a relatively short analysis time. The optimized method has a good repeatability over a wide linear range.
|