Textile Functionalization by Porous Protein Crystal Conjugation and Guest Molecule Loading

Protein crystals are versatile nanostructured materials that can be readily engineered for applications in nanomedicine and nanobiotechnology. Despite their versatility, the small size of typical individual protein crystals (less than one cubic mm) presents challenges for macroscale applications. One way to overcome this limitation is by immobilizing protein crystals onto larger substrates. Cotton is composed primarily of cellulose, the most common natural fiber in the world, and is routinely used in numerous material applications including textiles, explosives, paper, and bookbinding. Here, two types of protein crystals were conjugated to the cellulosic substrate of cotton fabric using a 1,1′-carbonyldiimidazole/aldehyde mediated coupling protocol. The efficacy of this attachment was assessed via accelerated laundering and quantified by fluorescence imaging. The ability to load guest molecules of varying sizes into the scaffold structure of the conjugated protein crystals was also assessed. This work demonstrates the potential to create multifunctional textiles by incorporating diverse protein crystal scaffolds that can be infused with a multiplicity of useful guest molecules. Cargo molecule loading and release kinetics will depend on the size of the guest molecules as well as the protein crystal solvent channel geometry. Here, we demonstrate the loading of a small molecule dye into the small pores of hen egg white lysozyme crystals and a model enzyme into the 13-nm pores delimited by “CJ” crystals composed of an isoprenoid-binding protein from Campylerbacter jejuni

Characterizing the Cytocompatibility of Various Cross-Linking Chemistries for the Production of Biostable Large-Pore Protein Crystal Materials

With rapidly growing interest in therapeutic macromolecules, targeted drug delivery, and in vivo biosensing comes the need for new nanostructured biomaterials capable of macromolecule storage and metered release that exhibit robust stability and cytocompatibility. One novel possibility for such a material are engineered large-pore protein crystals (LPCs). Here, various chemically stabilized LPC derived biomaterials were generated using three cross-linking agents: glutaraldehyde, oxaldehyde, and 1-ethyl-3-(3-(dimethylamino)­propyl)­carbodiimide. LPC biostability and in vitro mammalian cytocompatibility was subsequently evaluated and compared to similarly cross-linked tetragonal hen egg white lysozyme crystals. This study demonstrates the ability of various cross-linking chemistries to physically stabilize the molecular structure of LPC materialsincreasing their tolerance to challenging conditions while exhibiting minimal cytotoxicity. This approach produces LPC-derived biomaterials with promising utility for diverse applications in biotechnology and nanomedicine