Air-matrix digital microfluidics (DMF) apparatuses and methods of using them to prevent or limit evaporation and surface fouling of the DMF apparatus. In particular, described herein are air-matrix DMF apparatuses and methods of using them including thermally controllable regions with a wax material that may be used to selectively encapsulate a reaction droplet in the air gap of the apparatus; additional aqueous droplets may be combined with the encapsulated droplet even after separating from the wax, despite residual wax coating, by merging with an aqueous droplet having a coating of a secondary material (e.g., an oil or other hydrophobic material) that may remove the wax from the droplet and/or allow combining of the droplets.

Described is a method and device for detecting an analyte in a sample, comprising bringing a sample comprising a target analyte into contact with magnetisable particles, the particles being coated with binding molecules complementary to the target analyte, resulting in bound and unbound binder complexes, positioning the magnetisable particles, comprising both bound and unbound binder complexes, in proximity to a magnetic field sensor, changing the magnetic field sufficient to release at least a portion of the magnetisable particles, comprising both bound and unbound binder complexes, from their proximity to the magnetic field sensor, and measuring changes in a magnetic signal detected from the net movement, being either translational or rotational movement, of the magnetisable particles relative to the magnetic sensor.

The present application discloses methods and apparatus for detecting a complex including an analyte that include contacting a sample in a solution with a population of functionalized beads of a first type, which are magnetic functionalized beads and are functionalized to include a first moiety that associates with an analyte under suitable conditions, contacting the sample solution with a population of functionalized beads of a second type, which are functionalized to include a second moiety that associates with the analyte under suitable conditions, contact resulting in formation of a complex including one of the first type of functionalized bead, the analyte, and one of the second type of functionalized bead, and detecting the complex including the analyte by detecting magnetic fields produced by the magnetic functionalized bead and by detecting the functionalized bead of the second type associated with the analyte in the complex.

A bioassay system includes at least one conductive excitation coil, the at least one conductive excitation coil configured to generate an alternating magnetic field including a first frequency and a second frequency. The bioassay system further includes a sample mount configured to position a sample within the at least one conductive excitation coil, and at least one sensing conductive coil configured to determine a magnetic response of a sample positioned within the sample mount to the alternating magnetic field.

Devices for use in determining properties of biochemicals and macromolecules derived from a biological sample include a fluid control unit and a macromolecule measurement unit integrated on a monolithic platform. Devices and methods of measuring the properties of macromolecules using immobilized magnetic particles are also disclosed.

Bead arrays suitable for analysis by mass spectrometry are disclosed. In an embodiment, a bead array includes multiple reactive sites, each of the reactive sites being capable of binding multiple distinct target analytes.

The invention relates to a sensor device (100) and a method for the detection of magnetic particles (1) in a sample chamber (2) with a contact surface (11). The sensor device (100) comprises a sensor unit (120, 130) for detecting magnetic particles (1) in a target region (TR) and/or in at least one reference region on the contact surface. Moreover, it comprises a magnetic field generator (140) for generating a magnetic field that shall guide magnetic particles to the contact surface. With the help of these components, an “auxiliary parameter” is determined that is related to the magnetic particles (1) and/or their movement but that is independent of binding processes taking place in the target region between magnetic particles and the contact surface. The auxiliary parameter may for example be related to the degree of mismatch between the positions reached by the magnetic particles (1) under the influence of a magnetic field and the target region (TR). The evaluation results can be used to validate and/or correct the measurements obtained in the target region (TR).

A sample is added to a chamber (12) in which magnetic particles (P) are provided. The sample includes a target component (T) and the chamber (12) has a detection surface (122). A magnetic force is exerted on the magnetic particles (P) to attract the magnetic particles (P) to the detection surface (122). The bound magnetic particles that captured the target component (T) in the magnetic particles (P) and the unbound magnetic particles that captured no target component (T) in the magnetic particles (P) are held at the detection surface (122). At least part of the sample is drained out of the chamber (12) and a new sample added to the chamber (12). The magnetic force exerted on the magnetic particles (P) is altered to release the unbound magnetic particles from the detection surface (122). An amount of the bound magnetic particles that are held at the detection surface (122) are measured. The target component (T) is preconcentrated by repeating the steps of magnetically binding the target component (T) from the newly added sample and washing the detection surface (122) from unbound magnetic particles.

Disclosed herein are detection methods that use magnetic nanoparticles (MNPs) to allow molecules to be identified. Embodiments of this disclosure include methods of using magnetic sensors (e.g., magnetoresistive sensors) to detect temperature-dependent magnetic fields (or changes in magnetic fields) emitted by MNPs, and, specifically to distinguish between the presence and absence of magnetic fields emitted, or not emitted, by MNPs at different temperatures selected to take advantage of knowledge of how the MNPs' magnetic properties change with temperature. Embodiments disclosed herein may be used for nucleic acid sequencing, such as deoxyribonucleic acid (DNA) sequencing.

In one aspect, presence and/or level of an analyte within a sample is determined by use of a construct comprising a magnetic moiety and a fluorescent moiety. In one embodiment, the construct is magnetically migrated to a transparent surface and then dragged along the surface. In one aspect, an evanescent field is applied and changes in the diffusional or rotational properties of the fluorescent moiety as it migrates in and out of the evanescent field are measured by changes in its fluorescent emission, providing a measure of the interaction between the construct and a component of the sample.