Alignment of elongated particles in a particle delivery device

A device for delivery of particles into biological tissue comprising:

• at least one conduit;
• a propellant source fluidically coupled to the conduit and configured to deliver a propellant into the conduit;
• a particle source configured to release magnetic elongated particles into the conduit, the elongated particles having a width, w, a length, l>w, the propellant source and the conduit configured to propel the elongated particles in a collimated particle stream toward the biological tissue;
• an alignment mechanism comprising a magnetic field generator that is configured to generate a magnetic field within the conduit and align a longitudinal axis of the magnetic elongated particles to be substantially parallel to a direction of the particle stream in an alignment region of the conduit, wherein the aligned elongated particles are ejected from the conduit and impact the biological tissue.