Patent Application
20110220332
The following generally relates to micro channel devices and more particularly to temperature control of one or more fluids respectively traversing one or more micro channels of a micro channel device.
Micro channel devices include, but are not limited to, devices in which a small volume of a fluid is routed through a micro (sub-millimeter) channel of the device. Such devices have been used in biochip, lab-on-a-chip, inkjet printhead, and other micro channel based technologies. In some instances, a temperature of a fluid traversing a micro channel of a micro channel device is controlled so that it is within a predetermined temperature range for processing, analysis, and/or other purposes. Controlling the temperature includes heating and/or cooling the fluid so that the temperature of the fluid is within the predetermined temperature range.
One technique for heating and/or cooling the fluid involves using a Peltier device, which, generally, is a thermoelectric heat pump that transfers heat from one side of the Peltier device to the other side of the Peltier device. With this technique, the Peltier device is placed in thermal communication with the micro channel device, and an appropriate voltage is applied to the Peltier device to create a temperature gradient for transferring heat between the sides of the Peltier device, either away from or towards the micro channel device. The polarity of the applied voltage determines whether the Peltier device heats up or cools down the fluid in the micro channel device.
Unfortunately, a Peltier device (or the like) may require good mechanical/thermal contact between the Peltier device and the outside of the micro channel device. Such contact may require accurate and precise mechanical alignment and pressure. Furthermore, heat transfer via the Peltier device may be non-uniform through conduction via the side of the Peltier device in mechanical contact with the micro channel device. Furthermore, heat produced by the Peltier device may have to transfer through and thus may be absorbed by a thickness of a wall of the micro channel device before it reaches the desired channel(s). Moreover, using such a device may increase the thermal mass that participates in thermal cycling, which may increase the power required to implement thermal cycling.
As a consequence, using a Peltier or similar device may increase the overall size of the micro channel device, power consumption and/or dissipation of the micro channel device, and/or the cost of the micro channel device, as well as provide non-uniform and/or relatively slow and inefficient temperature control.
Aspects of the application address the above matters, and others.
In one aspect, a micro channel device includes at least one micro channel and at least one heating/cooling channel. The at least one heating/cooling channel is in thermal communication with the at least one micro channel. A temperature of a heating/cooling fluid in the least one heating/cooling channel determines a temperature of a fluid in the at least one micro channel.
In another aspect, a method includes controlling a temperature of a fluid in a micro channel of a micro device through a temperature of a heating/cooling fluid in a heating/cooling channel that is in thermal communication with the micro channel.
In another aspect, a micro channel device includes a micro channel and means, internal to the micro channel device, for controlling a temperature of a fluid in the micro channel.
Those skilled in the art will recognize still other aspects of the present application upon reading and understanding the attached description.
The application is illustrated by way of example and not limitation in the figures of the accompanying drawings, in which like references indicate similar elements and in which:
The following relates to micro channel devices. Such devices include device in which a volume of a fluid is transported through one or more micro (e.g., sub-millimeter, or nanometer to micron) channels or capillaries of the device. Examples of such a device include, but are not limited to, a biochip (e.g., for DNA, enzymatic, protein, etc. analysis), a lab-on-a-chip, an inkjet printhead, and/or other micro channel devices.
The micro channel device 100 includes a substrate 102. The substrate 102 may include glass, silicon, a polymer(s), ceramic, and/or one or more other materials. The illustrated substrate 102 includes N micro channels 1041, 1042, 1043, . . . , 104N, where N is an integer equal to or greater than one. The N micro channels are collectively referred to herein as micro channels 104. The micro channels 104 are configured for routing one or more fluids 114 such as a liquid, a gas, or other fluid.
A fluid control system 106 controls a flow of a fluid, such as one or more sample fluids 114 or other fluid, in a micro channel 104. The illustrated fluid control system 106 is located off the micro channel device 100 and includes a pressure system with a pump, a valve, a sensor, and/or one or more other components. The fluid control system 106 controllably moves the fluid through the micro channel 104 via pressure (e.g., high pressure) from the pressure system.
In another embodiment, at least a sub-portion of the fluid control system 106 is located on the micro channel device 100. Examples of components that may be located on the micro channel device 100 include, but are not limited to, one or more of a micro-pump, a micro-valve, a micro-sensor, and/or one or more other micro-components. Such components may be based on Micro Electro Mechanical Systems (MEMS) or other technology.
In the illustrated embodiment, at least one of the micro channels 104 is used to route a sample fluid to a processing region 108 where the sample fluid is processed. In the case of DNA analysis, this may include moving a bio-sample through one or more stages such as one or more of a purification stage, a priming stage, an amplification stage (e.g., via polymerase chain reaction (PCR)), a separation stage (e.g., via electrophoresis), an analysis stage, and/or other stage.
The micro channel device 100 also includes at least one heating/cooling channel 110. The illustrated embodiment includes a single heating/cooling channel 110 that is internal to the micro channel device 100 and that is in thermal communication with the micro channels 104. The illustrated heating/cooling channel 110 is separated from the micro channels by a predetermined finite distance. The illustrated distance is for explanatory purposes and is not limiting; this distance may be larger or smaller. In one non-limiting instance, the heating/cooling channel 110 is in physical contact with at least one of the micro channels 104. This may improve heat transfer efficiency relative to embodiments in which heat traverses through a portion of the micro channel device 100 before reaching the desired micro channel 104.
The heating/cooling channel 110 can be used to control the temperature of one or more fluids traversing one or more of the channels 104 to be within a predetermine temperature range. By way of example, the at least one heating/cooling channel 110 can route a heating/cooling fluid 116, such as liquid (e.g., water, oil, antifreeze, etc.), a gas (e.g., air, etc.), or other fluid, having a temperature within a predetermined temperature range. Generally, the predetermined temperature range of the heating/cooling fluid 116 corresponds to the predetermined temperature range of the fluid(s) 114 in the channels 104. The heating/cooling fluid 116 facilitates heating or cooling the fluid in the micro channels 104.
A thermal insulator can be included in the micro channel device 100 to facilitate mitigating thermal paths to other regions of the micro channel device 100.
A temperature control system 112 controls a temperature of the heating/cooling fluid 116 and hence the temperature of the sample fluid 114. The temperature controller 112 may include a temperature servomechanism or other feedback based system, and/or other system for dynamic temperature control. In the illustrated embodiment, a temperature sensor 118 senses a temperature of the fluid in a micro channel 104, and the temperature controller 112 controls the temperature of the heating/cooling fluid 116 based on the sensed temperature.
The heating/cooling fluid can facilitate heating and/or cooling the fluid in a micro channel over a predetermined temperature range. Examples of suitable temperatures include temperatures in a range of about zero degrees Celsius (0° C.) to about one hundred degrees Celsius (100° C.), such as about fifty degrees Celsius (50° C.), about fifty-nine degrees Celsius (59° C.), about seventy-two degrees Celsius (72° C.), about ninety-five degrees Celsius (95° C.), and/or other temperatures.
In the illustrated embodiment, the same fluid control system 106 is used to control the flow of both the sample fluid 114 and the heating/cooling fluid 116. In another embodiment, different fluid control systems 106 are employed for controlling the flow of the fluid 114 and the heating/cooling fluid 116.
It is to be appreciated that the relative geometry (e.g., shape, size, etc.) of the components herein (e.g., the micro channel device, the micro channels, the heating/cooling channels, etc.) are provided for explanatory purposes and are not limiting, and other geometries are contemplated herein.
Variations are contemplated.
With respect to
With respect to
In still another embodiment, the heating/cooling channel 110 is located outside of the micro channel device 100 and in thermal communication with the micro channels 104. In this instance, a temperature of a fluid in a micro channel 104 can still be controlled as described herein by controlling the temperature of the heating/cooling fluid flowing through the heating/cooling channel 110.
Other embodiments, including combinations of the above, are also contemplated herein.
At 1500, a temperature of a heating/cooling fluid is brought to within a predetermined temperature range.
As described herein, in one non-limiting instance this includes employing the temperature control system 112 to control the temperature of the heating/cooling fluid based on the predetermined temperature range.
At 1502, the heating/cooling fluid, which is at the predetermined temperature, is routed through a heating/cooling channel 110 that is in thermal communication with a micro channel 104.
As described herein, in one non-limiting instance this includes employing the fluid control system 106 to control the flow of the heating/cooling fluid in a heating/cooling channel 110.
At 1504, a fluid in the micro channel 104 is heated or cooled to be within a predetermined temperature range based on the temperature of the heating/cooling fluid flowing through the heating/cooling channel 110.
At 1506, the heated or cooled fluid is moved through the micro channel 104 via the fluid control system 106, for example, for subsequent processing.
The application has been described with reference to various embodiments. Modifications and alterations will occur to others upon reading the application. It is intended that the invention be construed as including all such modifications and alterations, including insofar as they come within the scope of the appended claims and the equivalents thereof.
