Preparation of Mineralized Nanofibers: Collagen Fibrils Containing Calcium Phosphate

Abstract

We report a straightforward, bottom-up, scalable process for preparing mineralized nanofibers. Our procedure is based on flowing feed solution, containing both inorganic cations and polymeric molecules, through a nanoporous membrane into a receiver solution with anions, which leads to the formation of mineralized nanofibers at the exit of the pores. With this strategy, we were able to achieve size control of the nanofiber diameters. We illustrate this approach by producing collagen fibrils with calcium phosphate incorporated inside the fibrils. This structure, which resembles the basic constituent of bones, assembles itself without the addition of noncollagenous proteins or their polymeric substitutes. Rheological experiments demonstrated that the stiffness of gels derived from these fibrils is enhanced by mineralization. Growth experiments of human adipose derived stem cells on these gels showed the compatibility of the fibrils in a tissue-regeneration context.

Bone tissue engineering via nanostructured calcium phosphate biomaterials and stem cells

“…48,55,56 However, the use of collagen is limited as it is costly, and its potential of antigenicity and pathogen transmission. 48,55,56 Gelatin is a denatured form of collagen, which is free of immunogenic concerns. Gelatin contains integrin binding sites which are important for cell adhesion.…”

To achieve self‐assembled collagen mimetic fibrils using designed peptides

“…[14,15] The D -periodicity of the fibrils is also involved in the resistance of the tensile strength of tissues, [16] and the mineralization of bones. [17] Thus, capturing the structural features of the D -period in collagen-mimetic materials represents a major step forward in developing biomaterials with improved, native-like properties and functionality.…”

Fibril formation pH controls intrafibrillar collagen biomineralization in vitro and in vivo

“…Fetuin's small dimension (<6 kDa) allows it to diffuse in all the water compartments within the collagen fibrils [12,16e18]. In addition, a flowing solution of inorganic cations and tropocollagen forced through a nanoporous membrane into an anion-rich receiving solution has successfully led to the formation of mineralized nanofibres [19].…”