Microwave irradiation and cross-linking of collagen

In a multifactorial experiment, dermal sheep collagen was treated in diluted glutaraldehyde solutions, 70% ethyl alcohol, Cialit 1:5000, and distilled water for 1, 3 and 5 min, respectively, in combination with microwave irradiation at different temperature settings. The shrinkage temperature indicating the degree of cross-linking achieved was then determined. Treatment in 0.65% glutaraldehyde with microwave irradiation setting for 60°C resulted in the maximum shrinkage temperature within 1 min, whilst at the lower setting of 50°C the maximum shrinkage temperature for both glutaraldehyde solutions is only reached after 5 min. Neither microwave irradiation by itself, Cialit or ethyl alcohol induce cross-linking of collagen fibres. These findings are relevant for implant studies.