INFRARED SPECTROSCOPIC DETECTION OF CHARGED PARTICLES: The Use of FTIR-ATR

The motivation of this book is to develop the merits of infrared spectroscopic based methods that could be used as a detector/identifier in biological detection systems. The methods described in this book are based on Attenuated Total Reflection (ATR) because of the requirement of detection of spores in water. The use of ATR requires concentrating the spores onto the surface of internal reflection elements (IRE). In chapter 3, an electrostatic method for concentrating Bacillus globigii spores on the ZnSe IRE with alumina coating is presented. In chapter 4, an electric field assisted ATR was developed and no coating of the IRE was required. Application of the electric field without flow leads to a rapid adsorption of the spores on the IRE. The spores could be easily and rapidly removed by flowing in a new sample.The work in chapter 5 explores the packing arrangement of kaolin particles on a ZnSe IRE under an applied electric field.Polarized IR spectroscopic measurement and AFM show that kaolin deposition rearranges a flatter orientation on the surface under E-field and no flow.