A system for continuous flow operation of a microfluidic chip, the system comprising: a microfluidic chip, comprising: (a) a first inlet configured to receive a first solution; (b) a second inlet configured to receive a second solution; and (c) a first mixer, comprising: (i) a first inlet microchannel configured to receive the first solution from the first inlet; (ii) a second inlet microchannel configured to receive the second solution from the second inlet; and (iii) a mixing microchannel configured to mix the first solution and the second solution to provide a nanoparticle solution at a mixer outlet; and (d) a chip outlet in fluid communication with the mixer outlet through a nanoparticle solution microchannel; a first continuous flow fluid driver configured to continuously drive the first solution from a first solution reservoir into the first inlet of the microfluidic chip; a second continuous flow fluid driver configured to continuously drive the second solution from a second solution reservoir into the second inlet of the microfluidic chip; and a system outlet in fluid communication with the chip outlet, wherein the system outlet is configured to output the nanoparticle solution; wherein the first mixer is a Dean Vortex Bifurcating Mixer (DVBM) comprising an inlet channel leading into a plurality of toroidal mixing elements arranged in series, and wherein: the plurality of toroidal mixing elements includes a first toroidal mixing element downstream of the inlet channel, and a second toroidal mixing element in fluidic communication with the first toroidal mixing element via a first neck region; the first toroidal mixing element has a first leg of a first impedance and a second leg of a second impedance, wherein the first impedance is greater than the second impedance; and the second toroidal mixing element has a first leg of a third impedance and a second leg of a fourth impedance, wherein the third impedance is greater than the fourth impedance, characterized in that the first neck region has a length of 0.2 mm or greater. a microfluidic chip, comprising: (a) a first inlet configured to receive a first solution; (b) a second inlet configured to receive a second solution; and (c) a first mixer, comprising: (i) a first inlet microchannel configured to receive the first solution from the first inlet; (ii) a second inlet microchannel configured to receive the second solution from the second inlet; and (iii) a mixing microchannel configured to mix the first solution and the second solution to provide a nanoparticle solution at a mixer outlet; and (d) a chip outlet in fluid communication with the mixer outlet through a nanoparticle solution microchannel; (a) a first inlet configured to receive a first solution; (b) a second inlet configured to receive a second solution; and (c) a first mixer, comprising: (i) a first inlet microchannel configured to receive the first solution from the first inlet; (ii) a second inlet microchannel configured to receive the second solution from the second inlet; and (iii) a mixing microchannel configured to mix the first solution and the second solution to provide a nanoparticle solution at a mixer outlet; and (i) a first inlet microchannel configured to receive the first solution from the first inlet; (ii) a second inlet microchannel configured to receive the second solution from the second inlet; and (iii) a mixing microchannel configured to mix the first solution and the second solution to provide a nanoparticle solution at a mixer outlet; and (d) a chip outlet in fluid communication with the mixer outlet through a nanoparticle solution microchannel; a first continuous flow fluid driver configured to continuously drive the first solution from a first solution reservoir into the first inlet of the microfluidic chip; a second continuous flow fluid driver configured to continuously drive the second solution from a second solution reservoir into the second inlet of the microfluidic chip; and a system outlet in fluid communication with the chip outlet, wherein the system outlet is configured to output the nanoparticle solution; the plurality of toroidal mixing elements includes a first toroidal mixing element downstream of the inlet channel, and a second toroidal mixing element in fluidic communication with the first toroidal mixing element via a first neck region; the first toroidal mixing element has a first leg of a first impedance and a second leg of a second impedance, wherein the first impedance is greater than the second impedance; and the second toroidal mixing element has a first leg of a third impedance and a second leg of a fourth impedance, wherein the third impedance is greater than the fourth impedance, characterized in that the first neck region has a length of 0.2 mm or greater.