The frequency dependences of the storage and loss shear moduli, G′ and G″, of pronase‐treated collagen dissolved in acetate buffer at pH 4.0 were measured at 17.0°C by use of the Birnboim‐Schrag multiple lumped resonator apparatus. Some of the solutions contained 70% glycerol. The infinite‐dilution moduli were determined and compared with theoretical models for a rigid cylinder and a semiflexible rod. Only the latter could fit the data. A rotational time of 144 μs and a slowest flexural relaxation time of 21 μs, both reduced to water at 20°C, were determined from the fit. The intrinsic viscosity and rotational relaxation time correspond to a semiflexible rod with persistence length of about 170 nm and a Young's modulus of 4 × 1010 dyn/cm2.
ASJC Scopus subject areas
- Organic Chemistry