Attoliter Control of Microliquid

Abstract

The technology of the sub-femtoliter volume control of liquids in nanometer range pipettes (nanopipettes) has been developed for carrying out surgical operations on living cells. We focus attention on an interface forming between oil and water in a nanopipette. The interface position can be moved by increasing or decreasing the input pressure. If the volume of liquid in the nanopipette can be controlled by moving the position of the interface, cell organelles can be discharged or suctioned and a drug-solution can be injected into the cell. Quantity volume control in the pico-attoliter range using a tapered nanopipette is controlled by the condition of an interface with a convex shape toward the top of the nanopipette. The volume can be controlled by the input pressure corresponding to the interfacial radius without the use of a microscope by preliminarily preparing the pipette shape and the interface radius as a function of the input pressure.

Applications of nanopipettes in the analytical sciences

“…As per the original intention of design, nanopipettes are useful in the deposition of small volumes. Commonly used as injection nozzles, 7,8,151 nanopipettes are well-suited for applications related to biological systems due to their precise spatial and injection control capabilities. 116,132 In these experiments, an isolated cell is punctured with the nanopipette and a potential is applied to deliver the species of interest from the filled nanopipette.…”

“…5,6 Recently, pipettes with tip openings on the scale of tens to hundreds of nanometres, hereafter referred to as nanopipettes, have been utilized in a number of fields related to the analytical sciences. Nanopipettes used to control and deposit ultra-small volumes [7][8][9][10][11][12] and for the development of electrochemical and optical sensors have been reported. [13][14][15][16] Applications of nanopipettes as probes in scanning probe microscopes have also been described.…”

Silica-Based Nanopipettes for Rapid Living Single-Cell Transfection

“…The delivery of cargo into cells has become a critical step in gene editing, , cell therapy, , and drug delivery. − Nanopipettes, due to their nanometer-sized sharp tip and ability to avoid damaging the objects they pierce, − have become a critical mechanical tool in intracellular delivery , and been used for injecting − and sampling − single living cells. Because most living animal cells have a small size (diameter < 30 μm) and ultralow concentration of the target, the single-cell research based on injecting and sampling with high spatial and temporal resolution ,, still faces considerable challenges.…”

Surfactant effects of gallium on quality of AlN epilayers grown via metal-organic chemical-vapour deposition on SiC substrates

“…AlN growth is best performed at higher temperatures than GaN growth, because Al atoms are less mobile than Ga atoms. High structural quality crack-free AlN epilayers grown at temperatures as high as 1500 • C were reported [13,14]. Because high-temperature metalorganic chemical-vapour deposition (MOCVD) systems require specialized heater and growth chamber designs, it is desirable to find methods for growing crack-free high-quality AlN at lower temperatures.…”