Mid-infrared Microspectroscopy of Difficult Samples Using Near-Field Photothermal Microspectroscopy

www.spectroscopyonl ine.com espite recent advances in Fourier transform-infrared (FT-IR) microspectroscopy and micro-attenuated total reflectance (ATR), for many types of samples there remains a need for even higher spatial resolution, or for a nondestructive method of recording localized mid-IR spectra from asreceived samples without the risk of damage or alteration by preparation techniques. A promising technique is the recently developed method of nearfield IR microspectroscopy using a photothermal probe. We discuss progress in the development of this technique and give examples of how it can be applied to the spectroscopic characterization of real-world samples. Following a brief survey of several limitations of the more commonly used mid-IR microspectroscopy sampling techniques, this article briefly discusses the variants of near-field scanning probe methods, in which lateral spatial resoluD Mid-infrared