Fabrication of 3D Micro-Blades for the Cutting of Biological Structures in a Microfluidic Guillotine

Abstract

Micro-blade design is an important factor in the cutting of single cells and other biological structures. This paper describes the fabrication process of three dimensional (3D) micro-blades for the cutting of single cells in a microfluidic “guillotine” intended for fundamental wound repair and regeneration studies. Our microfluidic guillotine consists of a fixed 3D micro-blade centered in a microchannel to bisect cells flowing through. We show that the Nanoscribe two-photon polymerization direct laser writing system is capable of fabricating complex 3D micro-blade geometries. However, structures made of the Nanoscribe IP-S resin have low adhesion to silicon, and they tend to peel off from the substrate after at most two times of replica molding in poly(dimethylsiloxane) (PDMS). Our work demonstrates that the use of a secondary mold replicates Nanoscribe printed features faithfully for at least 10 iterations. Finally, we show that complex micro-blade features can generate different degrees of cell wounding and cell survival rates compared with simple blades possessing a vertical cutting edge fabricated with conventional 2.5D photolithography. Our work lays the foundation for future applications in single cell analyses, wound repair and regeneration studies, as well as investigations of the physics of cutting and the interaction between the micro-blade and biological structures.

Determining protein polarization proteome-wide using physical dissection of individual Stentor coeruleus cells

“…We show that intracellular protein distributions can be mapped by physically dissecting a large cell into pieces and analyzing the fragments. For smaller cells, microfabricated cutting devices capable of working at the cellular level, [37][38][39] combined with increasing sensitivity for proteomic analysis of small samples such as a single mammalian cell, [40][41][42][43] should allow proteomic dissection, as demonstrated in this work, to become a general method for subcellular proteomics complementary to existing methods. 10,11,44 Conclusions A substantial fraction of all proteins is localized with respect to the global anterior-posterior body axis of the Stentor cell.…”