Embodiments disclosed include methods and apparatus for Fluorescent Enhanced Photothermal Infrared (FE-PTIR) spectroscopy and chemical imaging, which enables high sensitivity and high spatial resolution measurements of IR absorption with simultaneous confocal fluorescence imaging. In various embodiments, the FE-PTIR technique utilizes combined/simultaneous OPTIR and fluorescence imaging that provides significant improvements and benefits compared to previous work by simultaneous detection of both IR absorption and confocal fluorescence using the same optical detector at the same time.