Search

Electrospun polymer nanofibers with entrapped magnetic nanoparticles (magnetic NP-NF) represent a novel scaffold substrate that can be functionalized for single-step isolation and activation of specific lymphocyte subsets. Using a surface-embedded T cell receptor ligand/trigger (anti-CD3 monoclonal antibody), we demonstrate, as proof of principle, the use of magnetic NP-NF to specifically isolate, enrich, and activate CD3(+) T cells from a heterogeneous cell mixture, leading to preferential expansion of CD8(+)CD3(+) T cells. The large surface area, adjustable antibody density, and embedded paramagnetic properties of the NP-NF permitted enhanced activation and expansion; its use represents a strategy that is amenable to an efficient selection process for adoptive cellular therapy as well as for the isolation of other cellular subsets for downstream translational applications.

The construction of a trypsin column for rapid and efficient protein digestion in proteomics is described. Electrospun and alcohol-dispersed polymer nanofibers were used for the fabrication of highly stable trypsin coatings, which were prepared by a two-step process of covalent attachment and enzyme cross-linking. In a comparative study with the trypsin coatings on as-spun and nondispersed nanofibers, it has been observed that a simple step of alcohol dispersion improved not only the enzyme loading but also the performance of protein digestion. In-column digestion of enolase was successfully performed in less than 20 min. By applying the alcohol dispersion of polymer nanofibers, the bypass of samples was reduced by filling up the column with well-dispersed nanofibers, and subsequently, interactions between the protein and the trypsin coatings were improved, yielding more complete and reproducible digestions. Regardless of alcohol dispersion or not, trypsin coatings showed better digestion performance and improved performance stability under recycled uses than covalently attached trypsin, in-solution digestion, and commercial trypsin beads. The combination of highly stable trypsin coatings and alcohol dispersion of polymer nanofibers has opened up a new potential to develop a trypsin column for online and automated protein digestion.