A micromachined chemical amplifier was successfully used to perform the polymerase chain reaction (PCR) in continuous flow at high speed. The device is analogous to an electronic amplifier and relies on the movement of sample through thermostated temperature zones on a glass microchip. Input and output of material (DNA) is continuous, and amplification is independent of input concentration. A 20-cycle PCR amplification of a 176-base pair fragment from the DNA gyrase gene of Neisseria gonorrhoeae was performed at various flow rates, resulting in total reaction times of 90 seconds to 18.7 minutes.

We investigate the influence of annealing conditions on the physical properties of thin films of poly(3,4‐ethylenedioxythiophene)/poly(styrene sulfonate) (PEDOT/PSS). In particular, we describe how annealing temperature, the ambient gas, and choice of dopant affect the conductivity, morphology, and work function of the films. Two specific dopants are considered, sorbitol and glycerol, and broad guidelines are developed for using PEDOT/PSS as a hole‐injection electrode in polymeric light‐emitting devices, solar cells, and photodetectors.

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We describe the development of an enzyme assay inside picoliter microdroplets. The enzyme alkaline phosphatase is expressed in Escherichia coli cells and presented in the periplasm. Droplets act as discrete reactors which retain and localize any reaction product. The catalytic turnover of the substrate is measured in individual droplets by monitoring the fluorescence at several time points within the device and exhibits kinetic behavior similar to that observed in bulk solution. Studies on wild type and a mutant enzyme successfully demonstrated the feasibility of using microfluidic droplets to provide time-resolved kinetic measurements.