Effect of Initial Conformation on the Starch Biopolymer Film Formation Studied by NMR.

The formation of a rigid porous biopolymer scaffold from aqueous samples of 1% (suspension) and 5% (gel) corn starch was studied using optical and nuclear magnetic resonance (NMR) techniques. The drying process of these systems was observed using a single-sided NMR scanner by application of the Carr-Purcell-Meiboom-Gill pulse sequence at different layer positions. The echo decays were analyzed and spin-spin relaxation times () were obtained for each layer.

Heterogeneities in gelatin film formation using single-sided NMR.

Gelatin solutions were prepared in D(2)O. The drying process of cast solutions was followed with a single-sided nuclear magnetic resonance (NMR) scanner until complete solidification occurred. Spin-spin relaxation times (T(2)) were measured at different layers with microscopic resolution and were correlated with the drying process during film formation.