[KE.003] Coaxial micro/nanojets generated by EHD forces. Scaling laws

A method to generate electrified coaxial jets of immiscible liquids using the electrospray technique has been recently reported (Loscertales et al., Science, 295, 1695, 1 March 2002). Basically, when two immiscible liquids are injected at appropriate flow rates through two electrified capillary needles, one of them inside the other, the menisci of the two liquids adopt an almost conical shape with the outer meniscus surrounding the inner one. The thin jets issued from each vertex give downstream rise to the coaxial jet structure. This method has proved its ability to produce encapsulated particles in the micro/nanometric range with a well defined size, narrow size distribution, and good control over the coating thickness. Here, we present some experimental results of both the current transported through these coaxial jets and the size of the droplets resulting from the jet break-up. Different couples of liquids have been used to investigate the influence of the liquid properties on both the current and size.

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Micro-jets make designer droplets

28 February 2002

Drug delivery and food manufacturing could benefit from a new technique for coating tiny liquid droplets with other liquids. Ignacio Loscertales of the University of Malaga in Spain and colleagues have created a device that uses electrohydrodynamics to tailor the size of the