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Method Development and Sampling Techniques
Preparing Samples by State and Form
Description
Sample preparation depends on the state and form of the sample before analysis. It helps make the sample ready for accurate measurement. The main goal is to extract the analyte, which is the substance being measured, and remove parts that could interfere with the analysis.
Solid samples often nee...
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Transcript
样品制备是获得准确分析结果的关键步骤。它包括三个主要目标:提取、纯化和浓缩。
首先,萃取涉及从样品基质中分离含有目标分析物的混合物。其次,如果存在干扰物质,则将其去除以获得纯样品。第三,如果提取的分析物浓度较低,则将其浓缩至可准确检测的水平。
样品的常见形式是固体、液体和气体。太大而无法直接分析的固体块通过研磨、粉碎和研磨等物理方法制成粉末。
过筛和混合这种混合物会产生均匀的细粉末,然后将其干燥并溶解在合适的溶剂中,以将分析物提取到溶液中。
与固体不同,液体悬浮液在分析前经过过滤或离心,以去除不纯的固体颗粒。
由于固体吸附剂选择性吸附气态分析物,因此不需要对气体进行样品制备。
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