A Facile Approach for Fabricating Fluorescent Cellulose

Fluorescent cellulose nanocrystals (CNCs) were prepared through a two-step approach. Reactive amino groups were first introduced onto the CNCs through a silanization reaction with 3-aminopropyltrimethoxysilane. The fluorescent moieties were then attached onto the cellulose by covalent grafting between the amino groups and 1-pyrenebutyric acid N-hydroxy succinimide ester or fluorescein isothiocyanate. The synthesized fluorescent CNCs were investigated and characterized with attenuated total reflectance Fourier transform infrared spectroscopy, ultraviolet-visible absorbance and fluorescence spectroscopy, confocal microscopy, and dynamic light scattering. The same fluorescent functionalization strategy could also be applied to other cellulose materials, such as microcrystalline cellulose and bulky paper sheets. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 117: 3639-3644, 2010