Controlled deposition of electrospun nanofibers by electrohydrodynamic deflection

Electrospinning is a technique often used for the production of nanofibers composed of various polymers and ceramics. For enhanced material performance, it is desirable to obtain nanofibrous structures with a pre-determined microscopic fiber orientation and macroscopic geometry. However, it is challenging to control or predict the final deposition structure of an electrospun nanofiber due to the inherent instabilities induced along the polymer jet during the electrospinning process. Historically, mitigating these instabilities has been attempted electrically, magnetically, and mechanically with limited levels of success. Here, a new technique to electrically control the trajectory of an electrospun jet by electrohydrodynamic deflection is introduced. This protocol is achieved using a set of linearly actuated intermediary electrodes and a rapidly oscillating electric potential, driven by home-built AC amplifiers and a switching algorithm to control the amplitude, frequency, duty cycle, and the relative phase of the external electric field. Predetermined nanofibrous geometries are printed along predetermined paths using a 10% polyethylene oxide polymer solution.