An apparatus comprising: a body having an aperture dimensioned to receive an air-borne particle of corresponding size; first and second electrodes positioned within the aperture between which a potential difference can be applied; and a measurement circuit configured to measure an electrical property between the first and second electrodes such that the presence of the air-borne particle within the aperture can be detected based on a change in the electrical property when the air-borne particle contacts both the first and second electrodes.

Provided is a device for electrical measurement designed to be able to perform high sensitivity detection by reading not only changes in steady-state current, but also the occurrence of transient current, and an electrical measurement apparatus including the device for electrical measurement. The device for electrical measurement includes a substrate on which are formed at least a sample separation channel and a sample migration channel, as well as a sample measuring unit, with one end of the sample separation channel formed to connect to one end of the sample migration channel, and the sample measuring unit including a first measuring unit connected to the sample migration channel, and a second measuring unit connected to the sample migration channel from the reverse side to the first measuring unit.

A method of forming a nanopore in a lipid bilayer is disclosed. A nanopore forming solution is deposited over a lipid bilayer. The nanopore forming solution has a concentration level and a corresponding activity level of pore molecules such that nanopores are substantially not formed un-stimulated in the lipid bilayer. Formation of a nanopore in the lipid bilayer is initiated by applying an agitation stimulus level to the lipid bilayer. In some embodiments, the concentration level and the corresponding activity level of pore molecules are at levels such that less than 30 percent of a plurality of available lipid bilayers have nanopores formed un-stimulated therein.

A method of forming a nanopore in a lipid bilayer is disclosed. A nanopore forming solution is deposited over a lipid bilayer. The nanopore forming solution has a concentration level and a corresponding activity level of pore molecules such that nanopores are substantially not formed un-stimulated in the lipid bilayer. Formation of a nanopore in the lipid bilayer is initiated by applying an agitation stimulus level to the lipid bilayer. In some embodiments, the concentration level and the corresponding activity level of pore molecules are at levels such that less than 30 percent of a plurality of available lipid bilayers have nanopores formed un-stimulated therein.

A method of determining a charge of at least one test particle (as herein defined), comprising: applying one of an electric current or a voltage across an aperture connecting two chambers, whereby the chambers are at least partially filled with electrolyte and whereby the at least one test particle is suspended in the electrolyte of at least one of the chambers; measuring a value indicative of the other of the electric current or voltage across the aperture; determining a time interval between a first and a second point in time, the second point in time corresponding to a point in time when the measured current or voltage has reached a specific proportion of the measured current or voltage at the first point in time; and determining the charge of the at least one test particle by: determining a value indicative of an electrical velocity component of a total velocity of at least one calibration particle having a known charge, taking into account that the total velocity of the at least one calibration particle comprises a non zero-convective velocity component and the electrical velocity component; determining a value indicative of an electrical velocity component of a total velocity of the at least one test particle, taking into account that the total velocity of the at least one test particle comprises a non-zero convective-velocity component and the electrical velocity component; and using the determined values indicative of the electrical velocity components of the test particle and the calibration particle to calibrate the quantitative relationship between the charge of the at least one test particle and the determined time interval.

A method of forming a nanopore in a lipid bilayer is disclosed. A nanopore forming solution is deposited over a lipid bilayer. The nanopore forming solution has a concentration level and a corresponding activity level of pore molecules such that nanopores are substantially not formed un-stimulated in the lipid bilayer. Formation of a nanopore in the lipid bilayer is initiated by applying an agitation stimulus level to the lipid bilayer. In some embodiments, the concentration level and the corresponding activity level of pore molecules are at levels such that less than 30 percent of a plurality of available lipid bilayers have nanopores formed un-stimulated therein.

A sensing tip including a pipette tip having a cavity which communicates with an external environment of the pipette tip through an aperture located at a distal end of the pipette tip, and an impedance sensor having a sensing area including at least two electrodes located respectively outside and inside the pipette tip, wherein the sensing area is arranged within the aperture.

A device for biological material detection includes a substrate; a through-hole through which a biological material to be tested passes, the through-hole being formed in the substrate; a molecule that interacts with the biological material to be tested passing through, the molecule being formed in the through-hole; a first chamber member that forms, with at least the surface including the through-hole on one surface side of the substrate, a first chamber to be filled with electrolyte; and a second chamber member that forms, with at least the surface including the through-hole on the other surface side of the substrate, a second chamber to be filled with electrolyte. The biological material to be tested is identified by the waveform of the ion current (passage time, shape, etc.) when the biological material to be tested passes through the through-hole.

An object is to provide a device that can measure a moving time (velocity) of a single particle with high accuracy, and an ion current measuring apparatus and a zeta potential measuring apparatus with the device, and an ion current measuring method and a zeta potential measuring method. The object can be achieved by a device used for measurement of ion current, the device including: a substrate; and a channel formed in the substrate. The channel includes a sample liquid supply channel, a sample collection channel, and constricted channel formed between the sample liquid supply channel and the sample collection channel. The constricted channel includes three or more constricted parts each formed with a protrusion part, the three or more constricted parts are formed substantially straight in a direction from the sample liquid supply channel to the sample collection channel, and when the width of each of the constricted parts is defined as 1, the spacing between adjacent constricted parts is 0.5 to 3.

Provided is a device for electrical measurement designed to be able to perform high sensitivity detection by reading not only changes in steady-state current, but also the occurrence of transient current, and an electrical measurement apparatus including the device for electrical measurement. The device for electrical measurement includes a substrate on which are formed at least a sample separation channel and a sample migration channel, as well as a sample measuring unit, with one end of the sample separation channel formed to connect to one end of the sample migration channel, and the sample measuring unit including a first measuring unit connected to the sample migration channel, and a second measuring unit connected to the sample migration channel from the reverse side to the first measuring unit.