In uitro Calcification Model (2):Apatite Formation on Segmented Polyurethane Thin Films by Using an Alternate Soaking Process:The Effect of Adsorbed Serum Proteins on Calcification

摘要

In the present study,the effect of serum proteins on the calciffication (apatite deposition) of commercially available polyurethane (PU) films,Pellethane 2363-80AE,Pellathane 2363-55DE,and K-III,was evaluated by using an alternating soaking process.Bovine serum albumin,#gamma#-globulin and fibrinogen were used as typical serum proteins.After the proteins were adhered to PU films,the films were used in the apatite formation process.The thin-filmX-ray diffraction spectra of a fibrinogen adhered K-III sample,after 200 calcification sequences,showed HAp formation.The calcium content on the surface of all films to which protein adhered was greater than that of films incubated in protein free solutions.The films to which fibrinogen adhered showed remarkable apatite formation,though the amount of adhered fibrinogen was much smaller than the amounts of the other proteins.K-III films to which fibrinogen had adhered showed small globular apatite aggregations,whereas the Pellethane 2363 series films showed confetti-shaped apatite.Different morphologies exhibited by the deposits depended on the types of serum protein and on the substrate chemistry.The reason for the different apatite morphology on different PU films is not clear,however,the kind of serum protein seems to play an important role in the calcification of a PU.