Fiducial markers are provided on patterned arrays of the type that may be used for molecular analysis, such as sequencing. The fiducials may have configurations that enhance their detection in image or detection data, that facilitate or improve processing, that provide encoding of useful information, and so forth. Examples of the fiducials may include an always on type that respond to multiple frequencies of radiation used during processing and detection so as to return signals during successive cycles of imaging.

The present invention provides methods, compositions, and systems for distributing single polymerase molecules into array regions. In particular, the methods, compositions, and systems of the present invention result in a distribution of single polymerase molecules into array regions at a percentage that is larger than the percentage expected to be occupied under a Poisson distribution.

Fiducial markers are provided on patterned arrays of the type that may be used for molecular analysis, such as sequencing. The fiducials may have configurations and layouts that that enhance their detection in image or detection data, that facilitate or improve processing, that provide encoding of useful information, and so forth. Examples of the fiducials may include non-rectilinear layouts that may provide for more robust location of both the fiducials and sites of the array.

A fluidic device includes a plurality of reaction wells, typically in a dense array, with at least one bead retention segment in fluid communication with and spatially separated from at least one signal detection segment. A respective bead retention segment can be configured to hold a single bead, which can have a reagent attached thereto.

A device for performing biological sample reactions may include a plurality of flow cells configured to be mounted to a common microscope translation stage, wherein each flow cell is configured to receive at least one sample holder containing biological sample. Each flow cell also may be configured to be selectively placed in an open position for positioning the at least one sample holder into the flow cell and a closed position for reacting biological sample contained in the at least one sample holder. The plurality of flow cells may be configured to be selectively placed in the open position and the closed position independently of each other.

An example of a flow cell includes a base support, a reversibly swellable resin positioned over the base support, and a depression defined in the reversibly swellable resin. The reversibly swellable resin includes at least one hydrophilic monomer selected from the group consisting of a poly(ethylene glycol) based monomer, poly(propylene glycol) based monomer, and combinations thereof. The depression has a first opening dimension when the reversibly swellable resin is in a non-swelled stated and has a second opening dimension, that is smaller than the first opening dimension, when the reversibly swellable resin is in a swelled state.

Provided in some aspects are methods of patterning a surface in situ for producing an array on the surface, for example, by partitioning of beads comprising oligonucleotides into spatially predefined regions, to generate unique DNA sequences in spatial positions in the array. Compositions such as nucleic acid arrays produced by the methods are also disclosed.

High surface area coatings are applied to solid substrates to increase the surface area available for solid-phase synthesis of polymers. The high surface area coatings use three-dimensional space to provide more area for functional groups to bind polymers than an untreated solid substrate. The polymers may be oligonucleotides, polypeptides, or another type of polymer. The solid substrate is a rigid supportive layer made from a material such as glass, a silicon material, a metal material, and plastic. The coating may be thin films, hydrogels, microparticles. The coating may be made from a metal oxide, a high- dielectric, a low- dielectric, an etched metal, a carbon material, or an organic polymer. The functional groups may be hydroxyl groups, amine groups, thiolate groups, alkenes, n-alkenes, alkalines, N-Hydroxysuccinimide (NHS)-activated esters, polyaniline, aminosilane groups, silanized oxides, oligothiophenes, and diazonium compounds. Techniques for applying coatings to solid substrates and attaching functional groups are also disclosed.

Fiducial markers are provided on patterned arrays of the type that may be used for molecular analysis, such as sequencing. The fiducials may have configurations that enhance their detection in image or detection data, that facilitate or improve processing, that provide encoding of useful information, and so forth. Examples of the fiducials may include an always on type that respond to multiple frequencies of radiation used during processing and detection so as to return signals during successive cycles of imaging.

A lateral flow assay is capable of detecting and differentiating viral and bacterial infections. A combined point of care diagnostic device tests markers for viral infection and markers for bacterial infection, to effectively assist in the rapid differentiation of viral and bacterial infections. In some preferred embodiments, bimodal methods and devices determine if an infection is bacterial and/or viral. A dual use two strip sample analysis device includes a first lateral flow chromatographic test strip to detect MxA and a low level of C-reactive protein and a second lateral flow chromatographic test strip to detect high levels of C-reactive protein. In some preferred embodiments, the sample is a fingerstick blood sample.