Comparison of normalized FTIR and AFM-IR spectra.

Spectra acquired on (A) PMMA and (B) cancellous bone. In the cancellous bone, the newly formed bone was located on the trabecular edge (in the first 20 microns) and more mature bone was closer to the center of the trabecula. No major shifts were observed between the two techniques, but differences in shapes and ratios are evident. In the amide band of the bone spectra (B), the amide II peak was significantly smaller in the AFM-IR spectra and a shoulder was evident around 1600 cm-1 not present in the FTIR spectra. In the mineral band for the newly formed bone, the shoulder corresponding to the peak 1128 cm-1 was more prominent.