The fluorescence spectra from the neat alanine + 1,2-indanedione solution and neat Rhodamine 6G were measured using a spectrometer (Ocean-Optics, USB 4000+) and by exciting with 473 nm and 532 nm lasers. The obtained spectra are shown in Fig. 5. Alanine is required to combine with 1,2-indanedione to produce the fluorescence. The action of 1,2-indanedione was also tested by developing fingerprints on white paper (a porous surface where hydrophilic aminoacids also can adhere well). After 24 h of application of the dye, one could easily observe the fingerprint even under room light conditions while the fluorescence from the fingerprint was seen under a fluorescence microscope. Fluorescence spectra from the samples on paper show a peak at 559 nm under blue light excition with a half width of 30 nm, and a peak at 600 nm under green light excitation with a half width of 26 nm. The fingermarks on aluminum and glass with the CaF2 CTF deposited and post-treated with 1,2-indanedione solution shows broadband emission under blue and green excitations. The half width of the fluorescence peak is about 80 nm under either blue or green excitation. The broadening is likely to be due to the inhomogeneous environment of the CTF.