Solubilized collagen, enzyme

A variety of methods for preparing collagen films from enzyme-solubilized, monomeric collagen with diflFerent surface structures were evaluated. Our initial interest was to determine the effects of various preparative techniques on the in vivo behavior of the films. 

Figure 1 is a control (not crosslinked) film prepared by method II with enzyme-solubilized collagen. The film was removed after 7 days... 

Figure 2 is the same type of film removed after 14 days of intramuscular implantation. Here the collagen is fragmented and infiltrated with infiammatory cells. After 21 days, all control films disappeared except for the ones prepared from a mixture of insoluble collagen fiber and enzyme-solubilized collagen. Some of these remained for 30 days. 

All of the crosdinked implants lasted for at least 60 days. At this time, a few of the enzyme-solubilized collagen films crosslinked with either glutaraldehyde or dialdehyde starch appeared to be thinner. Some of the films crosslinked with glutaraldehyde appeared to be somewhat thinner after 90 days, although most were intact. 

Figure 3 is a method II enzyme-solubilized collagen film crosslinked with glutaraldehyde and implanted subcutaneously. It was unchanged after 90 days. 

Chein, J. C. W., and Wise, W. B. (1975). Biochemistry 14, 2786. A 1 3C Nuclear Magnetic Resonance and Circular Dichroism Study of the Collagen-Gelatin Transformation in Enzyme Solubilized Collagen. 

Fig. 8. The network structure of type IV collagen as deduced from electron microscopy of fragments solubilized with proteases (Timpl et at., 1981). The top left micrograph shows the short form of the 7 S region. In the top right, a more limited enzyme digestion allows a portion of the helical domain of each molecule to remain linked to the 7 S domain. The bottom left micrograph shows isolated dimeric NCI fragments and, at the lower right, dimeric triple helical material connected in the center by the NCI domain.

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