添加樣品分析

Standard Addition Analysis

添加樣品分析係將適當體積且已知濃度之待測物標準品添加於樣品，以檢測方法分析添加標準品之樣品與未添加之樣品；由測得之檢測訊號、樣品體積、待測物標準品濃度與添加之標準品體積，利用簡易公式求得樣品中待測物濃度。本文除回顧添加樣品分析，亦介紹添加標準品體積小於樣品體積百分之一的微量體積添加樣品分析。運用微量體積添加樣品分析除可求得樣品中待測物濃度，並可確認樣品基質是否干擾檢測方法。本文亦探討基質對檢測方法之干擾型式以及基質干擾對以微量體積添加樣品分析求得之待測物濃度的影響。

The standard addition analysis is a method to determine the concentrationof an analyte in an unknown sample via adding a proper quantity of thevolume of a known-concentration standard solution of the analyte to thesample. The added sample and the sample are measured individually byan analytical method. The concentration of the analyte in the sample canthen be calculated by using a simple formula with the information of themeasured analytical signals collected from the analytical method, thesample volume, the concentration and the added volume of the standardsolution. Besides reviewing the standard addition analysis, this articlepresents the minor volume standard addition analysis, in which a minorquantity of the volume of the standard solution is added to the sample.The minor quantity of the added volume is defined as one percent or less ofthe sample volume. The minor volume standard addition analysis is capableof not only determining the concentration of the analyte in the sample,but also identifying the interference from the matrix of the sample on theanalytical method. This article also discusses the types of matrix inter- ference on the analytical method and the effect of matrix interference onthe concentration of an analyte as determined by the minor volume standardaddition analysis.