Control of Cryopreservation Procedures on Blood Vessels Using Fiber X-Ray Diffraction

Abstract Aim We sought to determine variations in fiber organization at the molecular level using x-ray diffraction analyses on human blood vessel specimens after cryopreservation processes. Materials and Methods Diffractometric profiles were performed on aortic and carotid cryopreserved-thawed vessel samples (CVS) versus the same fresh vessel samples (FVS). X-ray diffraction was performed on vascular tissues from 17 cadaveric donors after informed consent. Measurements utilized a Seifert Scintag PAD-II powder diffractometer with CuKa radiation; λ = 1.5418 Å. Scans were evaluated in the 5° to 60° range in theta −2theta mode, in the 5° to 60° range in 2-theta, with steps 0.1° and 10 seconds per step. Ten aortic and 8 carotid diffractometric profiles were analyzed, using differential planimetric surfaces measured under x-ray diffraction curve. Diffractographic profiles were analyzed according to intervals based upon the ages of the donors. An ordering profile coefficient (OPC) was obtained as the quotient between the differential planimetric surface (DPS) of FVS versus CVS vessel ordering diffraction. Results There was a decreased ordering profile according to age: older donors showed less ordering than younger ones. Clear peaks at d-spacing of 2.86 Å and 2.15 Å (2-theta = 31.3° and 42.0°, respectively) were always confirmed despite the different profiles of samples. OPC showed a higher ordering profile among the CVS than FVS: 70% aortas and 62.5% carotids. Conclusion The cryopreserved-thawed procedure does not damage the fibrillar organization of vessels.