Characterization of chitin from Illex argentinus squid pen

β-Chitin from Illex argentinus squid pens was isolated by using chemical methods and the pens composition determined. The structural characteristics of β-chitin were identified with infrared (IR), solid-state cross-polarization/magic-angle-spinning (CP-MAS) 13C NMR spectroscopy and X-ray analysis. The viscosity average molecular weight Mv, calculated from the intrinsic viscosity was above 2 × 106 g mol−1. The stiffness of the macromolecule was analyzed using the Yamakawa and Fujii theory for wormlike cylinders.