Matrix isolation and theoretical study of the photochemical reaction of CrCl2O2 with chloroethenes.

The matrix-isolation technique has been combined with infrared spectroscopy to identify and characterize the products formed by irradiation of cage-paired CrCl(2)O(2) and a series of chloroethenes, C(2)H(x)()Cl(y)() (x + y = 4). For each system, oxygen-atom transfer occurred upon irradiation, yielding the corresponding acetyl chloride derivative and the Cl(2)CrO species. The products were formed in the same matrix cage and strongly interacted to form a distinct molecular complex after formation.

In vitro degradation of silk fibroin.

A significant need exists for long-term degradable biomaterials which can slowly and predictably transfer a load-bearing burden to developing biological tissue. In this study Bombyx mori silk fibroin yarns were incubated in 1mg/ml Protease XIV at 37 degrees C to create an in vitro model system of proteolytic degradation. Samples were harvested at designated time points up to 12 weeks and (1) prepared for scanning electron microscopy (SEM), (2) lyophilized and weighed, (3) mechanical properties determined using a servohydraulic Instron 8511, (4) dissolved and run on a SDS-PAGE gel, and (5) characterized with Fourier transform infrared spectroscopy.