Nanopipette apparatus for manipulating cells
Disclosed herein are methods and systems for controlled ejection of desired material onto surfaces including in single cells using nanopipettes, as well as ejection onto and into cells. Some embodiments are directed to a method and system comprising nanopipettes combined with an xyz controller for depositing a user defined pattern on an arbitrary substrate for the purpose of controlled cell adhesion and growth. Alternate embodiments are directed to a method and system comprising nanopipettes combined with an xyz controller and electronic control of a voltage differential in a bore of the nanopipette electroosmotically injecting material into a cell in a high-throughput manner and with minimal damage to the cell. Yet other embodiments are directed to method and system comprising functionalized nanopipettes combined with scanning ion conductance microscopy for studying molecular interactions and detection of biomolecules inside a single living cell.
1. A system for manipulating an individual cell on a substrate, the system comprising:
an apparatus, comprising:
(a) a double-barreled nanopipette, having
(i) a first barrel containing a first electrode arranged to be in contact with a first liquid in the first barrel;
(ii) a second barrel adjacent the first barrel containing a second, reference electrode arranged to be in contact with a second liquid in the second barrel; and
(b) an xyz controller attached to said double-barreled nanopipette for effecting mechanical movements of the double-barreled nanopipette in submicron x and y steps, and effecting movement of said double-barreled nanopipette in a z direction towards or away said individual cell on the substrate, said xyz controller further having electronic controls comprising a field-programmable gate array (FPGA) programmed for controlling said mechanical movements according to user defined control; and
(c) a circuit, comprising a relay and an amplifier, connected to said first electrode, said FPGA, and to a high voltage source responsive to said FPGA, wherein said relay is configured to connect the high voltage source to the first electrode for applying an ejection voltage to said first electrode to eject said first liquid from the first barrel at a desired location, remove said ejection voltage when the xyz controller effects mechanical movement of the nanopipette away from the desired location, and connect the amplifier to said first electrode for providing a bias voltage between said first electrode and said second, reference electrode and for providing current measurement of ionic current through the first barrel;
said apparatus further operatively connected to the substrate containing said individual cell, whereby the individual cell may be injected with the ejected first liquid.
2. The apparatus of claim 1 wherein said amplifier comprises a low noise amplifier.
3. The apparatus of claim 1 further comprising a piezoelectric actuator for submicron control of the xyz controller.
4. The apparatus of claim 1 wherein said FPGA is further programmed to inject an organelle within said individual cell.
5. The apparatus of claim 1 wherein said substrate is adapted to contain a plurality of said individual cells, one cell each, in individual locations.
6. The apparatus of claim 5 wherein each individual location comprises a cavity defined in the substrate and sized for receiving only one of the plurality of individual cells.
7. The apparatus of claim 6 wherein the cavity comprises through-holes for applying negative pressure to hold the individual cell in the cavity.
8. The apparatus of claim 7 wherein the cavity comprises an electrode for attracting the individual cell to the cavity.
9. A method for injecting a material into an individual cell on a substrate, comprising the steps of:
(a) providing the system of claim 1 comprising the apparatus operatively connected to the substrate containing the individual cell;
(b) placing the first liquid comprising the material into the first barrel of the double barreled nanopipette;
(c) placing the second liquid into the second barrel of the double barreled nanopipette;
(d) actuating the xyz controller to penetrate the individual cell with the double barreled nanopipette;
(e) applying the ejection voltage to the first electrode to electrophoretically inject the material into the cell.
10. The method of claim 9 further comprising the step of immobilizing said cell on said substrate by placing said cell in a cavity defined in the substrate, said cavity sized to hold only an individual cell.
11. The method of claim 10 further comprising the step of applying a pressure differential across said cavity to aid in immobilizing said cell.
12. The method of claim 10 wherein said material injected is selected from the group consisting of a polynucleic acid, an antibody, and a dye.