Mechanically strong silk fibroin cryogels with two generations of pores were produced by carrying out the cryogelation reactions within the pores of the initial single-network (SN) fibroin cryogels. In this way, cryogels with interpenetrated and interconnected double- (DN), and triple-network (TN) structures were produced from fibroin solutions frozen at −18 °C in the presence of butanediol diglycidyl ether cross-linker and N,N,N′,N′-tetramethylethylenediamine as a pH regulator. Cryogel scaffolds formed at fibroin concentrations above 25 wt% exhibit a Young's modulus between 66 and 126 MPa, and sustain around 90% compressions under 87–240 MPa stresses. These values are the largest reported so far for fibroin scaffolds and hence the materials have promising applications in bone tissue engineering. We also show that the improvement in the mechanical performance of cryogels after multiple-networking is due to their increased content of fibroin network. Both DN and TN cryogels have two generations of interconnected macropores with diameters 20–30 μm and 3–9 μm. The size of both large and small pores could be adjusted by the relative amounts of fibroin in the network components.

通过在最初的单网络（SN）丝素蛋白冰晶格的孔内进行冷冻凝胶化反应，可以生产出具有两代孔的机械强度高的丝素蛋白冰晶格。这样，在丁二醇二缩水甘油醚交联剂和N，N，N存在下，由在-18°C下冷冻的丝蛋白溶液制备了具有互穿和相互连接的双（DN）和三网（TN）结构的冷冻凝胶。 ′，N′-四甲基乙二胺作为pH调节剂。在纤维蛋白浓度高于25 wt％时形成的低温凝胶支架表现出66至126 MPa之间的杨氏模量，并在87–240 MPa应力下承受约90％的压缩。这些值是迄今为止为止针对纤维蛋白支架的最大报道，因此该材料在骨组织工程中具有广阔的应用前景。我们还表明，在多次联网后，冷冻凝胶的机械性能有所提高，这是由于它们增加了丝蛋白网络的含量。DN和TN冷冻凝胶都有两代相互连接的大孔，直径分别为20–30μm和3–9μm。大孔和小孔的大小都可以通过网络组件中纤维蛋白的相对含量进行调整。