Sample interview questions: Describe your familiarity with different types of sample preparation techniques used in food analysis.
Sample answer:
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Solid-Phase Extraction (SPE):
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Technique used to extract target analytes from solid or liquid samples by selectively binding them to a solid phase, such as silica, alumina, or polymeric sorbents.
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Common in food analysis for extracting pesticides, drugs, mycotoxins, and other contaminants from complex matrices like soil, sediment, and food.
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Liquid-Liquid Extraction (LLE):
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Technique involving the transfer of analytes from one immiscible liquid phase to another.
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Widely used in food analysis to extract hydrophobic compounds like pesticides, oils, and fats from aqueous samples.
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Solid-Phase Microextraction (SPME):
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Non-exhaustive extraction technique that uses a coated fiber to selectively extract target analytes from a sample.
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Popular in food analysis for its simplicity, speed, and ability to be coupled with various analytical instruments.
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Supercritical Fluid Extraction (SFE):
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Technique utilizes a supercritical fluid, such as carbon dioxide, to extract target analytes from solid or liquid samples.