Microextraction Tech

Single drop microextraction (SDME) can be considered the first technique in the liquid phase microextraction context. It is a simple procedure which involves sampling and injection in the same device in a similar way to solid phase microextraction. In this case, a small drop (usually in the range from 1 to 5 µL) is suspended in the needle of a microsyringe which is immersed in the sample or kept into close contact with its headspace. Single drop-based microextractions usually present problems derived from the instability of the drop which results in its detachment when volumes higher than 5 µL are employed. This limitation has also a clear influence in the absolute recovery of the extraction technique and it may restrict its coupling with liquid chromatography where higher injection volumes are required. In 2006, Lu et al. presented the so-called directly suspended droplet microextraction (DSDME) which overcame some of these limitations. This single drop-based technique consists...