As a mature sample pretreatment technique, solid phase microextraction (SPME) completes sampling, extraction and concentration at one step. With the technique, little amount of samples are needed and organic solution is seldom used. In addition, the technique can be easily used in combination with other analyzing equipment. However, it also has some shortcomings, such as short service life, valunerablity to fraction, etc, which has limited its application.

Researchers from Key Laboratory of Chemistry of Northwestern Plant Resources, Chinese Academy of Sciences, have developed a new titanium oxide extraction bar which can be used for SPME. They have received a Chinese invention patent for the technique on October 31. The patent number is ZL200810184479.3.

The titanium oxide extraction bar is prepared as follows: a plurality of titanium oxide layers are deposited on the surface of polypropylene hollow fiber by adopting a sol-gel method. And then polypropylene matrix is removed by high-temperature firing, so as to obtain the titanium oxide hollow fiber extraction bar.

The extraction bar has a three-dimensional porous stricture, larger specific surface area, controllable coating thickness, good chemical and heat stability, wide pH stabilization range (pH=1~14) and high extraction efficiency to the polar compounds.

It is expected to be used in extraction preenrichment to polar compounds with micro and trace amount in medicine and environment samples.