Maskless arrayed nano-fibre mats by bipolar pyro-electrospinning.

The numerous advantages of micro and nanostructures produced by electrospinning (ES) have stimulated enormous interest in this technology with potential application in several fields. However, ES has still some limitations in controlling the geometrical arrangement of the fibre mats so that expensive and time-consuming technologies are usually employed for producing ordered geometries. Here we present a technique that we call 'bipolar pyro-electrospinning' (b-PES) for generating ordered-arrays of fibre mats in a direct manner by using the bipolar pyroelectric field produced by a periodically poled lithium niobate crystal (PPLN). The b-PES is free from expensive electrodes, nozzles and masks because it makes use simply of the structured pyroelectric field produced by the PPLN crystal used as collector. The results show clearly the reliability of the technique in producing a wide variety of arrayed fibre mats that could find application in bioengineering or many others field. Preliminary results of live cells patterning under controlled geometrical constraints is also reported and discussed in order to show potential exploitation as scaffold in tissue engineering.