Abstract: Nucleotides and nucleotide analogs are used in various sequencing by incorporation/sequencing by synthesis methods. Nucleotide analogs comprising 3?-blocking groups are used to provide reversible chain-termination for sequencing by synthesis. Typical blocking groups include phosphate groups and carbamate groups. Fluorescent nucleotides are used to perform sequencing by synthesis with detection by incorporation of the fluorescently labeled nucleotide, optionally followed by photobleaching and intercalating dyes are used to detect addition of a non-labeled nucleotide in sequencing by synthesis with detection by intercalation. Microfluidic devices, including particle arrays, are used in the sequencing methods.

Abstract: Time dependent iterative reactions are carried out in microscale fluidic channels by configuring the channels such that reagents from different sources are delivered to a central reaction zone at different times during the analysis, allowing for the performance of a variety of time dependent, and/or iterative reactions in simplified microfluidic channels. Exemplary analyses include the determination of dose responses for biological and biochemical systems.

Abstract: Methods for determining total analyte concentrations and amounts, especially in combination with analyte separations are provided. Microfluidic devices are used to separate analyte mixtures and detect the individual analytes. Signal areas are summed for each individual analyte to quantitate the total analyte amount. Separate measurements of the total analyte sample are also used to determine total analyte concentration.

Abstract: Methods and devices for reducing evaporation of sample materials from the wells of multiwell plates are disclosed which find particular utility when the plates are placed in a stacked configuration. An example of the methods includes providing at least a first multiwell plate which is configured to be placed in a stacked configuration with at least one second multiwell plate, the at least first multiwell plate having a plurality of wells for receiving sample material therein and opposing side walls which extend around the plate and which define a ridge spaced inwardly of the side walls and extending around the plate between the side walls and the plurality of wells, the method including at least partially filling the ridge with a liquid such as water or buffer solution. The ridge can include one or more ribs which extend upwardly from a lower surface of the ridge to help reduce sloshing of the liquid contained within the ridge and to add structural strength and rigidity to the multiwell plate.