Particle sorter with neutralized collection wells and method of using same

A particle sorting apparatus comprising:

• means for forming discrete droplets of particles from a flowing liquid stream containing said particles;
• means for detecting particles in the stream;
• means responsive to the detecting means for charging some droplets of selective interest with a positive charge and some with a negative charge;
• means for separating said charged droplets of selective interest;
• and
• means for collecting droplets of said selective interest, charged with opposite polarities, in the same ungrounded collection means so that the electrical charge of said collection means is substantially neutralized.

A method for sorting particles moving in a liquid stream according to differences in particle parameters comprising:

• producing a continuous liquid stream containing particles therein;
• detecting particles in said stream;
• modulating the flowing liquid stream to disrupt its continuous flow and cause discrete particle-containing droplets to be formed;
• electrically charging selected droplets, with a charge of selective polarity, responsive to said detecting of particles;
• deflecting charged droplets in an electrostatic field of a selective polarity to separate same from uncharged or oppositely charged droplets;
• simultaneously and periodically reversing the respective polarities of the charge applied to droplets and that of said electrostatic field;
• and
• collecting sorted particles of the same selective interest, some of which have opposite charges thereon, in a collection well inside which the electrical charge is substantially neutralized.

A method for sorting particles comprising:

• forming discrete droplets of particles from a flowing liquid stream containing said particles;
• detecting particles in the stream;
• charging droplets of selective interest, responsive to said detection of particles, some with a positive charge and some with a negative charge;
• separating said charged droplets of selective interest;
• and
• collecting droplets of said selective interest, charged with opposite polarities, in the same ungrounded collection means so that the electrical charge of said collection means is substantially neutralized.