Dagalakis N, Flink J, Stasikelis P, Burke J F, Yannas I V
J Biomed Mater Res. 1980 Jul;14(4):511-28. doi: 10.1002/jbm.820140417.
Several methods are compared for preparing collagen-glycosaminoglycan (GAG) membranes of high or low porosity. Collagen-GAG membranes have been used to cover satisfactorily large experimental full-thickness skin wounds in guinea pigs over the past few years. Methods studied as means for controlling pore size are confined to purely physical processes which do not require use of additives or chemical reagents to form the porous membrane. We find that membranes, initially swollen in distilled water or saline, shrink linearly to no less than 94% of original dimension after freeze drying; to 75% after critical point drying (from CO2, following water-ethanol exchange); and to 41% of original dimension following air drying from the swollen state. Scanning electron microscopic study of the pore structure resulting from eah drying procedure confirms our major conclusion: A carefully designed freeze drying process, two variants of which are described in detail, yields membranes with the highest mean pore size, as measured by quantitative stereological procedures. Critical point drying gave significantly more shrinkage and a lower mean pore size than either one of the two freeze drying procedures used.
比较了几种制备高孔隙率或低孔隙率胶原-糖胺聚糖（GAG）膜的方法。在过去几年中，胶原-GAG膜已被用于令人满意地覆盖豚鼠的大型实验性全层皮肤伤口。作为控制孔径的方法所研究的方法仅限于纯粹的物理过程，这些过程不需要使用添加剂或化学试剂来形成多孔膜。我们发现，最初在蒸馏水或盐水中膨胀的膜，冷冻干燥后线性收缩至不小于原始尺寸的94%；临界点干燥（从二氧化碳，经过水-乙醇交换后）后收缩至75%；从膨胀状态空气干燥后收缩至原始尺寸的41%。对每种干燥程序产生的孔结构进行扫描电子显微镜研究证实了我们的主要结论：精心设计的冷冻干燥过程（详细描述了其中两种变体）产生的膜具有最高的平均孔径，这是通过定量体视学程序测量的。临界点干燥比所使用的两种冷冻干燥程序中的任何一种都产生了明显更多的收缩和更低的平均孔径。
