HTC-15 - Abstract

Abstract Title: Investigating the potential for improved temperature responsive separations in liquid chromatography
Abstract Type: Seminar
Session Choice: Green Separations
Presenter Name: Mr Mathijs Baert
Co-authors:Mr Steven Martens
Prof Filip Du Prez
Prof Frederic Lynen
Company/Organisation: Ghent University
Country: Belgium

Abstract Information :

The use of polymer derived stationary phases in liquid chromatography, either as a replacement for or as a hybrid silica based stationary phase, has been expanding in last decades. An interesting discovery in this field has been the development of temperature responsive stationary phases, wherein a temperature responsive polymer is used to achieve separation.1 This type of polymer is an "intelligent material", as it is able to respond to a small variation in its surroundings with a sharp change in its physical properties. In the case of temperature responsive polymers, they possess a unique characteristic that allows them to change their water solubility based on changes in the ambient temperature. More specifically they show a decrease in polarity with increasing temperature. Implementing this polymer into a bonded-phase for liquid chromatography, allows for the control of the column polarity through control of the column temperature. This introduces the possibility to perform reversed phase like liquid chromatography in pure water, whereby the polarity is controlled through temperature, therefore eliminating the need for any organic modifiers.

Although successful implementation of this technique has already been demonstrated for several applications, the technique is still in its developmental stage. As a result, this strategy has not yet reached its full potential and is still being plagued by several shortcomings. Examples of this are, the often too low polymer coupling efficiencies resulting in low carbon loading, the questionable stability of the silica base at elevated temperature in fully aqueous conditions, or the less than optimal peak capacities which have been reached thus far.

In this contribution strategies are described to increase overall performance of temperature responsive columns in purely aqueous HPLC. This includes the development of improved coupling reactions between the polymers and the silica support, the study of alternative supporting materials and the development of temperature responsive stationary phases allowing for higher column efficiencies. Next to this, the applicability and potential of this promising separation mode will be illustrated through a number of (1D and 2D) applications.