A gold nanohole array is functionalized with a cortisol thiol derivative, and binding to a monoclonal antibody is conveniently detected using the sensitive shift in the 1060 nm transmission peak of the array. Detection is also enhanced 3-fold by the application of a secondary antibody-gold nanoparticle conjugate. This regenerable response represents a more sensitive shift than that obtained previously for higher affinity binding and opens the way to application of nanohole arrays in immunobiosensing of important biomolecules.

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We report a microfluidic fluorescence activated cell-sorting (μFACS) device that employs traveling surface acoustic waves (TSAW) to sort cells at rates comparable to conventional jet-in-air FACS machines, with high purity and viability.

Two distinct mechanisms are investigated for transferring a pure 87 Rb Bose-Einstein condensate in the |F = 2, m F = 2〉 state into a mixture of condensates in all the m F states within the F = 2 manifold. Some of these condensates remain trapped whilst others are output coupled in the form of an elementary pulsed atom laser. Here we present details of the condensate preparation and results of the two condensate output coupling schemes. The first scheme is a radio frequency technique which allows controllable transfer into available m F states, and the second makes use of Majorana spin flips to equally populate all the manifold sub-states. More recently, the production of multi-component condensates has revealed intriguing quantum fluid dynamics, and enabled precise measurement of relative quantum phase [9]. Experiments at JILA have focused on mixtures involving atoms in different ground state hyperfine levels (quantum number F), and coupling with a two photon (microwave plus radio frequency) transition. Experiments at MIT have used an optical dipole trap to confine a condensate occupying all magnetic sub-states (quantum number m F ) of the same hyperfine level [10]. Spin exchange processes result in domain formation which exhibits an anti-ferromagnetic interaction [11]. An important aspect of that work is the confinement of condensed atoms in sub-states which cannot be magnetically trapped.In this paper we present the results of two techniques for transforming a single state |F = 2, m F = 2〉 87 Rb Bose condensate into a mixture of all five magnetic sub-states of the F = 2 hyperfine level. Two of these states are magnetically confined (|2, 2〉 and |2, 1〉), with magnetic moments differing by a factor of 2, and the other states are unconfined.Applying an RF field similar to that used in the evaporative cooling stage of the experiment we can couple atoms between adjacent m F states. It is possible to control the number of atoms which are coupled from the |2, 2〉 state into the other m F states: condensates with predetermined sub-state populations can be constructed. For example, we can limit the transfer into untrapped states.

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Summary Recent years have brought enormous progress in cell-based lab-on-a-chip technologies, allowing dynamic studies of cell death with an unprecedented accuracy. As interest in the microfabricated technologies for cell-based bioassays is rapidly gaining momentum, we highlight the most promising technologies that provide a new outlook for the rapid assessment of programmed and accidental cell death and are applicable in drug discovery, high-content drug screening, and personalized clinical diagnostics.

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The output of a grating-stabilized external-cavity diode laser was injected into a semiconductor tapered amplifier in a master-oscillator power amplifier configuration, producing as much as 500 mW of power with narrow linewidth. The additional linewidth that is due to the tapered amplifier is much smaller than the typical linewidth of grating-stabilized laser diodes. To demonstrate the usefulness of the narrow linewidth and high output power, we used the system to perform Doppler-free two-photon spectroscopy with rubidium.