Fragmented Nanofibers with Bulky Aggregation Behavior\nfor a Turbidimetric Immunoassay

Much attention has been paid to nonspherical\npolymer particles,\nwhich have hidden and intriguing properties compared to those of conventional\nspherical particles. Polymeric nanofibers are one type of nonspherical\nnanomaterial, but fabricating such nanofibers stably suspended in\nwater and controlling their aggregation and dispersion properties\nremain a challenge. Herein, we propose a top-down method to fabricate\nnonspherical and fragmented nanofibers stably suspended in water.\nWe use a simple procedure: (i) electrospinning of the polystyrene\nnanofibers, (ii) fragmentation by homogenizer, and (iii) surface modification\nof the fragmented nanofibers. Intriguingly, the fragmented nanofibers\nafter precipitation were bulkily packed together, compared to spherical\nparticles, due to their nonspherical shape and the stiffness derived\nfrom polystyrene. Using this unique property, we demonstrate that\nfragmented nanofibers with a bulky aggregation property can provide\nspecific, visual, and highly sensitive detection of antigen. The fragmented\nnanofibers may be a candidate carrier for an alternative to a conventional\nlatex turbidimetric immunoassay.