Improved resolution and detection of nanoparticles are achieved when a nanopore connecting liquid compartments in a device running on the Coulter principle is provided with fluid coatings such as lipid walls. Fluid lipid walls are made of a lipid bilayer, and preferably include lipid anchored mobile ligands as part of the lipid bilayer. By varying the nature and concentration of the mobile ligand in the lipid bilayer, multifunctional coatings of lipids are provided.

The present invention provides methods and systems to combine the capabilities of a hematology analyzer with those of a flow cytometer to yield a far more powerful analytical system than either device alone. In one embodiment, a method of analyzing a cell sample includes receiving a first data generated by an analysis of a first aliquot of the sample on a first particle analyzer having a fluorescence measurement device such as a flow cytometer, detecting at least one unresolved cell population in the first data, and accessing a second data stored on a storage device wherein the second data was previously generated by interrogating a second aliquot of the sample using at least one of a cell volume measurement device and a cell conductivity measurement device in a second particle analyzer such as a hematology analyzer. The unresolved cell population in the first data is then resolved using the second data. Corresponding system embodiments are also disclosed.

A nano-Coulter counter (nCC) device can include: an inlet; a plurality of nanochannels having a nanopore, wherein each nanochannel includes an inlet tapered region coupled to an inlet of the nanopore, wherein each nanopore has the second cross-dimension of at least about 50 nm to about 300 nm, and a pore length of at least about 50 nm to about 300 nm, wherein each nanochannel includes an outlet expansion region coupled to an outlet of the nanopore that expands from the second cross-dimension to a third cross-dimension that is larger than the second cross-dimension; an outlet microchannel fluidly coupled to an outlet of each of the plurality of nanochannels; an electrode pair having one electrode at the inlet microchannel and another electrode at the outlet microchannel; a power source electrically coupled with the electrode pair; and a pump operably coupled with the plurality of nanochannels.

A method of forming a plurality of lipid bilayers over an array of cells in a nanopore based sequencing chip is disclosed. Each of the cells comprises a well. A first salt buffer solution with a first osmolarity is flowed over a cell in the nanopore based sequencing chip to substantially fill a well in the cell with the first salt buffer solution. A lipid and solvent mixture is flowed over the cell to deposit a lipid membrane over the well that encloses the first salt buffer solution in the well. A second salt buffer solution with a second osmolarity is flowed above the well to reduce the thickness of the lipid membrane, wherein the second osmolarity is a lower osmolarity than the first osmolarity such that an osmotic imbalance is created between a first volume inside the well and a second volume outside the well.

Systems and methods described herein employ focused acoustic energy applied to a reservoir containing a fluid to eject a fluid sample from the fluid sample reservoir, e.g. to an inlet of an analytical device. In many embodiments, the ejected fluid sample traverses an air gap separating the inlet of the analytical device from an upper surface of the fluid in the fluid sample reservoir. In many embodiments, the ejected fluid sample comprises one or more droplets ejected from the fluid sample reservoir, which can contain particles in the fluid sample.

A biological particle counting system can include: an impedance particle counter comprising at least one sample aperture; a pump configured to pull particles through the at least one sample aperture of the impedance particle counter for counting, the pump producing a vacuum pressure; and a stepper motor configured to adjust a speed of the pump to substantially maintain the vacuum pressure.

Systems, devices, and methods for determining health characteristics are disclosed herein. In some embodiments, a method includes receiving a fluid sample from a user and transferring at least some of the biological cells of the fluid sample through a microchannel including (i) an upstream viscosity-elimination section sized to compress the biological cells and (ii) a downstream measurement section sized to keep the biological cells compressed to measure one or more elastic characteristics of the biological cells. The method can continue by measuring parameters of the biological cells at first and second detection regions of the downstream measurement section, and determining, based on the measured parameters of the biological cells at at least one of the first or second detection region, a health characteristic of the user.

A method of forming a plurality of lipid bilayers over an array of cells in a nanopore based sequencing chip is disclosed. Each of the cells comprises a well. A first salt buffer solution with a first osmolarity is flowed over a cell in the nanopore based sequencing chip to substantially fill a well in the cell with the first salt buffer solution. A lipid and solvent mixture is flowed over the cell to deposit a lipid membrane over the well that encloses the first salt buffer solution in the well. A second salt buffer solution with a second osmolarity is flowed above the well to reduce the thickness of the lipid membrane, wherein the second osmolarity is a lower osmolarity than the first osmolarity such that an osmotic imbalance is created between a first volume inside the well and a second volume outside the well.