摘要:
Low intensity light is incident upon a photodiode whose output is coupled to an integrator. The output of the integrator is coupled to an input of an A/D converter, whose output is coupled to a microprocessor, whose output is coupled to a filter. A second output of the microprocessor is coupled to a gate electrode of a FET to provide a reset signal to the FET to reset the integrator. The microprocessor compares the digital samples of the integrated signal from the A/D converter and, firstly, generates the reset signal if a sample is beyond a set limit, and, secondly, calculates delta values between adjacent samples and interpolates the delta values for the reset periods so as to provide a continuous data stream which can be filtered by a filter matched to the form of the original signal.
摘要:
Low intensity light is incident upon a photodiode whose output is coupled to an integrator. The output of the integrator is coupled to an input of an A/D converter, whose output is coupled to a microprocessor, whose output is coupled to a filter. A second output of the microprocessor is coupled to a gate electrode of a FET to provide a reset signal to the FET to reset the integrator. The microprocessor compares the digital samples of the integrated signal from the A/D converter and, firstly, generates the reset signal if a sample is beyond a set limit, and, secondly, calculates delta values between adjacent samples and interpolates the delta values for the reset periods so as to provide a continuous data stream which can be filtered by a filter matched to the form of the original signal.
摘要:
A miniaturized column analytical apparatus having a miniaturized column device containing a body with an elongate separation compartment is provided. Two or more sets of spaced apart antennas are positioned along the elongate separation compartment. The elongate separation compartment has first and second opposing sides along its elongate dimension. Each set of antenna contains a plurality of antennas. One antenna from each set is associated with at least one antenna from each of the other sets to form repeating sequences of antennas along the separation compartment on the opposing sides of the separation compartment. Each set of the antennas is associated with a different oscillating electrical potential to provide a plurality of oscillating electric fields along the elongate separation compartment to draw a target substance along the elongate separation compartment toward an exit end of the separation compartment. The detector can detect a target substance passing out of the elongate separation compartment.
摘要:
A method and apparatus for mixing liquids using electroosmotic flow. Multiple capillaries (100, 104, 106) or microchip channels meet at a common junction (102). One capillary (100) is used for mixed liquids and each of the remaining capillaries (104, 106) are used for supplying a liquid (112, 114) to be mixed. Each of the supply capillaries (104, 106) has a free end that is immersed into a vial (108, 110) of liquid (112, 114). A first power supply terminal (112) is attached to a free end of the mixed liquid capillary (100). The liquid in each vial has an electrode that is switchably connected to a second power supply terminal. Closing a switch (116, 118) causes liquid to flow from a vial through the common junction and through the mixed liquid capillary. Each switch is independent and each may be closed continuously, switched at a constant duty cycle, or switched at a variable duty cycle. As a result, continuous mixing or variable ratio mixing may be achieved.
摘要:
A method for removing fluid in a microfluidic device, the microfluidic device having a fluid channel, a first well, and a second well, the first well and the second well being coupled to a first end of the fluid channel, the method including applying a pressure difference between the second well and the first well, and applying a pressure difference between the first end and a second end of the fluid channel being below a certain threshold, for at least partly removing a first fluid from a first supply line coupled between the first well and the first end of the fluid channel.
摘要:
Miniaturized planar column devices for use in a liquid phase separation apparatus are described. The devices include microstructures that have been fabricated by laser ablation in a variety of novel support substrates. Devices formed according to the methods of the invention include associated laser-ablated features required for function, such as on-device reservoirs or makeup flow compartments, analyte detection means and sample injection means. The miniaturized columns can be used in an apparatus intended for analysis of either small and/or macromolecular solutes in the liquid phase which employs chromatographic, electrophoretic or electrochromatographic separation means. The apparatus can include a variety of optional injection means, manifolds, keeper means, post column collection means, and combinations thereof.
摘要:
In a method of forming a microchannel and/or microcavity structure by bonding together two elements (1, 2) having opposed plane surfaces of the same or different material, one or both surfaces having open channels and/or cavities, bonding is effected by applying to one or both element surfaces (1, 2) a thin layer (3) of a solution of a material capable of fusing with and having a lower melting point than that of the material or materials of the two element surfaces (1, 2) in a solvent which substantially does not dissolve the element surface material or materials. The solvent is then removed, and the two elements (1, 2) are brought together and heated to a temperature where the dissolved material is caused to melt but not the element surface material or materials.
摘要:
Miniaturized planar column devices are described for use in liquid phase analysis, the devices comprising microstructures fabricated by laser ablation in a variety of novel support substrates. Devices formed according to the invention include associated laser-ablated features required for function, such as analyte detection means and fluid communication means. Miniaturized columns constructed under the invention find use in any analysis system performed on either small and/or macromolecular solutes in the liquid phase and may employ chromatographic, electrophoretic, electrochromatographic separation means, or any combination thereof.
摘要:
A fluid supply unit is described, with the fluid supply unit comprising a fluid dispenser with an orifice adapted for dispensing a fluid, and a microfluidic device comprising an inlet port located at one of the faces of the microfluidic device. The fluid supply unit is adapted for establishing a fluidic contact between a droplet formed at the fluid dispenser's orifice and an inlet port of the microfluidic device, and the fluid supply unit is adapted for electrophoretically moving charged compounds from the droplet towards the inlet port.
摘要:
A microfluidic system comprises a first reservoir, an injection channel fluidically coupled to the first reservoir and to an injection point adapted for injecting an amount of fluid, and a side channel fluidically coupled to the injection channel at an intersection point located between the first reservoir and the injection point, the side channel being fluidically coupled with a second reservoir. Both the injection channel and the side channel are at least partly filled with a first substance and the second reservoir is at least partly filled with a second substance. The first substance is a gel and the second substance is a buffer solution. The side channel's cross section is larger than the injection channel's cross section.