Bioassays relying on magnetic read-out using probe-tagged magnetic nanobeads are potential platforms for low-cost biodiagnostic devices for pathogen detection. For optimal assay performance it is crucial to apply an easy, efficient and robust bead-probe conjugation protocol. In this paper, sensitive (1.5 pM) singleplex detection of bacterial DNA sequences is demonstrated in a portable AC suscep...

Coated beads retain great importance in the study of cell adhesion and intracellular communication; we present a generally applicable method permitting spatiotemporal control of bead adhesion from cells. Herein we demonstrate in vitro release of a poly-d-lysine (PDL) layer from anionic polystyrene beads, allowing complete bead release from rat cortical neurons post-adhesion.

The initial rate of platelet aggregation induced by adenosine diphosphate and thrombin correlated with the number of platelets retained when samples of citrated blood from the same normal donors were passed through glass bead columns. The results support the view that the glass bead column method of measuring platelet ;adhesiveness' is influenced by platelet aggregation.

[reaction: see text] A bromine-/chlorine-containing mass-tag encoding strategy for a small-molecule OBOC combinatorial library is reported. The resulting MALDI FTMS isotope pattern of each tag clearly defines the component building blocks of each "hit" bead in an 1890-member demonstration library screened on-bead for binding against streptavidin via both enzyme-linked colorimetric and Quantum D...

During transmitter release, synaptic vesicle membrane is specifically inserted into the nerve terminal plasma membrane only at specialized sites or "active zones." In an attempt to obtain a membrane fraction enriched in active zones, we have utilized the electric organ of the marine ray. From this organ, a fraction enriched in nerve terminals (synaptosomes) was prepared by conventional means. T...

We describe a simple single-particle tracking approach for monitoring the length of DNA molecules in tethered particle motion experiments. In this method, the trajectory of a submicroscopic bead tethered by a DNA molecule to a glass surface is determined by videomicroscopy coupled to image analysis. The amplitude of motion of the bead is measured by the standard deviation of the distribution of...

BACKGROUND Over the last ten years, miniaturized multiplexed immunoassays have become robust, reliable research tools that enable researchers to simultaneously determine a multitude of parameters. Among the numerous analytical protein arrays available, bead-based assay systems have evolved into a key technology that enables the quantitative protein profiling of biological samples whilst requiri...

A propeller-wash bead filter (PWBF) and a fluidized sand filter (FSF) on a 28 m recirculating system stocked with tilapia maintained favorablewater quality at five different feed rates, ranging from 0.9 to 4.5 kg feed per day. TAN removal rates ranged up to about 200 g TAN/m of media per day for each of the units. Peak rates of 244 g TAN/m of media per day were observed when the recirculating f...

We present the initial results of a cytometer that uses an array of extruded high-performance dielectrophoretic traps to capture, hold, and selectively release multiple single bioparticles. We have fabricated small arrays of traps and demonstrated single-bead and single-cell trapping, electrically switched bead release from single traps, fluorescence microscopy of trapped viable single cells, a...

The transient surface flow occurring when a cylindrical pile of dry granular material is suddenly allowed to spread on a horizontal plane is investigated experimentally as a function of the released mass M, the initial aspect ratio a of the granular cylinder pile, the properties of the underlying substrate ~smooth or rough, rigid or erodible! and the bead size. Two different flow regimes leadin...