Our technique, a combination of atomic force microscopy (AFM) and IR spectroscopy, can be employed to create label-free chemical maps at the nanoscale. AFM-IR enables IR spectroscopy with a spatial resolution well below conventional optical diffraction limits. It acquires IR absorption imaging with lateral resolution down to 100 nm. It consists of a near-field technique based on photothermal expansion of a sample due to the absorption of IR radiation.