evaporator

Abstract

The present invention includes an evaporator comprising a plate holder arranged to hold a multiwell plate rigidly such that a horizontal top surface of the multiwell plate is positioned vertically at a desired height, at least one gas heated injection manifold arranged above the plate holder and having at least one injection nozzle positionable at approximately the desired height, each nozzle adapted to inject an inert drying gas into a corresponding well of the multiwell plate, and one or more heating elements configured to warm the inert drying gas upstream of injection into the wells, at least one heating element being a heat sink integrated into the at least one manifold. The present invention also includes a method of evaporating a solvent using an inert gas preheated by one or more heat sinks.

Description

[Technical Field]

[0001] Technical Field The present invention relates to the area of ​​evaporation, and more particularly to an apparatus and method for evaporating liquids such as organic solvents. [Background technology]

[0002] background A laboratory evaporator is a device that can remove liquids such as water or organic solvents from preparations that need to be dried. Many industries use laboratory evaporators to prepare samples for analysis. For this reason, the pharmaceutical, food, and petroleum industries, as well as chemical laboratories, all use evaporators.

[0003] Laboratory evaporators can use kinetic, gas, heat, or some combination to produce dry samples ready for analysis. Specifically, in sample preparation, which is commonly performed prior to analytical procedures such as liquid chromatography, mass spectrometry, etc., evaporator devices are generally grouped as gas evaporators, such as nitrogen evaporators, vacuum evaporators, or rotary evaporators.

[0004] U.S. Patent No. 5,176,799 (Biotage AB) relates to an evaporation device including a container defining an opening in its upper portion and forming an evaporation chamber for holding a liquid composition. A condenser assembly is disposed above the container and sealed to the container. The condenser assembly has a wall defining a condensation chamber communicating with the evaporation chamber through the opening, an accumulator for receiving liquid condensed on the wall, and a drain for removing the liquid received by the accumulator. A fluid driver is disposed above the condenser assembly and adapted to generate a fluid flow downward through the condensation chamber, contacting the liquid composition in the evaporation chamber, and then generating a fluid flow upward into the condensation chamber. A heating mechanism for heating the liquid composition is disposed within the evaporation chamber to evaporate the liquid composition, and cooling means is disposed for cooling the wall to cause condensation of vapor contained in the fluid flowing upward from the evaporation chamber on the wall.

[0005] U.S. Patent No. 6,357,141 (Biotage AB) relates to an evaporation system for evaporating solvent from chemical samples held in a supply plate, which accelerates evaporation by warming the sample in a hot air bath. The system includes an adapter that allows for the use of supply plates of various heights, such as standard microplates or deep-well microplates. Specifically, the specification describes an apparatus for evaporating solvent from chemical samples held in a standard supply plate, the supply plate being of a type having a horizontal upper surface in which multiple supply wells are disposed. The apparatus includes: a drying chamber for directing an inert drying gas to the chemical sample, a first locator adapted to firmly hold a first of the plates so that the horizontal upper surface of the first plate is positioned vertically at a desired height; a first inert gas injection manifold having a number of injection nozzles equal to the number of feed wells, the number of nozzles being positionable at approximately the desired height, with one nozzle for each corresponding well in the number of feed wells in the first plate, each nozzle adapted to inject the inert dry gas into the corresponding well and onto the corresponding chemical sample therein, whereby the dry gas evaporates the solvent from the corresponding chemical sample to form a mixture of inert gas and solvent gas; an exhaust device for removing the mixture of inert gas and solvent gas from the apparatus; and a warming chamber that is atmospherically isolated for the drying chamber and adapted to immerse the underside of the supply plate in hot air to accelerate the evaporation.

[0006] U.S. Patent No. 6,357,141 teaches that the described adapter, which provides hot ate from below the plate, individually bathes each well while avoiding mixing and dilution and / or contamination with inert dry gas that comes into contact with the sample.

[0007] Porvair Sciences sells the Ultravap® series of blowdown evaporators, designed to remove the traditional laboratory "bottleneck" of solvent evaporation from microplates. Some instruments are designed with a flat front profile, and a platform shuttle allows for interfacing with liquid-handling robots for automation efficiency. According to the supplier, these products offer reproducible sample throughput through recent advances in gas injection technology to deliver heated gas directly and consistently into each well and tube. The gas is provided as a continuous stream, warmed by in-line heating.

[0008] Finally, WO 2017 / 186679 (Biotage AB) describes an evaporation device for evaporating liquids in test tubes, which includes at least one manifold with at least one nozzle and a tank unit for the liquid with an associated heater for the liquid. The device is configured to supply a preheated gas (pre-heated gas) heated by other or additional heating means arranged downstream of the inlet. h It has been proposed that a vaporizer system using a gas-burning system (e.g., a gas-burning system) can be utilized. WO 2017 / 186679 teaches that in conventional vaporizer systems, the gas flow from each nozzle is highly dependent on the pressure in the gas system between the pressure regulator and the nozzle. At low gas flow rates, the gas pressure provides the desired flow through the nozzle. However, at high gas flow rates, the flow resistance of the gas system limits the gas flow, which can be counteracted by overpressure generated in the system. While in prior art systems, pressure was controlled by a manual pressure regulator, WO 2017 / 186679 teaches a control unit configured to gradually increase the gas pressure from a first low pressure to a set pressure. Summary of the Invention [Problem to be solved by the invention]

[0009] In summary, the field of laboratory evaporators is continually in need of new solutions that allow for efficient evaporation using evaporators that are fast and easy to operate with low energy consumption. For example, the field needs evaporators with more efficient heating that reduce energy consumption. Other needs include faster sample processing and devices that better fit into the limited space provided in most laboratories.

[0010] definition The term "multiwell plate" is used herein to refer to a plate of any size containing multiple wells.

[0011] As used herein, the term "heat sink" refers to a passive heat exchanger that transfers heat generated by an electronic or mechanical device to a fluid medium where it is dissipated from the device, thereby enabling regulation of the device's temperature. As is well known, a heat sink comprises a heat exchange element combined with a heat source of appropriate dimensions.

[0012] The term "open loop" is used herein to refer to a control system in which the input modifies the output, but the output does not have a feedback loop and therefore does not affect the input. Open loop is used when there is no need to maintain strict temperature tolerances and the operating environment is stable. [Means for solving the problem]

[0013] Summary of the Invention In a first aspect, the present invention relates to an evaporator comprising: a plate holder arranged to firmly hold a multiwell plate such that a horizontal upper surface of the multiwell plate is positioned vertically at a desired height; The system includes at least one gas-heated injection manifold positioned above the plate holder and having at least one injection nozzle positionable at approximately the desired height, each nozzle adapted to inject an inert drying gas into a corresponding well of the multi-well plate; and one or more heating elements configured to heat the inert drying gas upstream of injection into the wells, wherein at least one heating element is a heat sink integrated into the at least one manifold.

[0014] Thus, the present invention has discovered the unexpected advantage of using an integrated heat sink in a manifold, which by definition is designed as a cooler, most commonly found in integrated circuits, as the heating element in laboratory evaporation. The heat sink provides the maximum surface area in contact with the surrounding medium, which in this context contributes to more efficient heating than is used by prior art evaporators.

[0015] As will be appreciated by those skilled in the art, by incorporating the heating element into the manifold, the space required for an evaporator according to the present invention is significantly reduced compared to an evaporator using a conventional in-line heater. Also, due to the integration, the total heating mass, i.e., everything that needs to be heated to heat the gas to the required level, is reduced compared to conventional solutions with in-line heaters. Due to the fact that the heat sink is very close to the nozzle, there is a more predictable relationship between the gas nozzle temperature and the heat sink temperature.

[0016] The evaporator of the present invention also has less heat loss and faster heat-up time to operating temperature compared to the prior art because both the size and thermal mass of the heated components are kept to a minimum.

[0017] The advantage of the heat sink can be taken advantage of to obtain a uniform temperature of the heated gas, the temperature of which is advantageously maintained within a predetermined range or at a predetermined value by open loop control.

[0018] Those skilled in the art can easily select the appropriate type and features for a given multi-well plate evaporator. For example, the heat sink may be a pin cooler, such as a straight or flared pin cooler.

[0019] Air velocity, material selection, protrusion design, and surface treatment are factors that affect the performance of the heat sink and therefore may influence the type selected. The heat sink may be made from aluminum or copper, for example.

[0020] To allow for smooth, low energy operation, a heating element such as a heat sink may be provided for idle thermal operation.

[0021] Evaporators according to the present invention are advantageously laboratory-type instruments, many of which are known and commonly used. For example, the aforementioned U.S. Patent No. 6,357,141 can provide further guidance regarding the known basic principles of evaporators that may also be applicable to the apparatus and methods described herein.

[0022] One advantage of the present invention is that the use of a heat sink allows the instrument to use a mathematical model that uses gas flow and the required nozzle temperature as inputs to calculate the heater temperature required to reach the required (or desired) nozzle temperature. Thus, as described in more detail below in connection with the method of the present invention, the heating element can heat to the correct temperature without the use of gas flow. As a result, gas consumption can be reduced compared to the prior art.

[0023] As is evident from the above, the evaporator according to the invention has the correct temperature from the start when the gas flow is initiated.

[0024] If desired, the device may be kept in a standby type preheat mode with low heat loss, so that the user can begin evaporating immediately.

[0025] Multiwell plates are available in a variety of sizes and have a wide range of wells. The vaporizer of the present invention can be arranged to be connected online with one or more downstream analytical devices, which may be selected from the group consisting of gas chromatographs, liquid chromatographs, mass spectrometers, and devices for flow injection analysis.

[0026] The present invention is useful for reducing the volume of a solvent to a certain extent, or to a dry or near dry state. For example, an evaporator according to the present invention can be used to reconcentrate a liquid sample.

[0027] Therefore, another aspect of the present invention is a method for evaporating a solvent using a preheated inert gas, the method comprising: providing an evaporator comprising: a plate holder; at least one gas injection manifold disposed above the plate holder and having at least one injection nozzle, each nozzle adapted to inject an inert drying gas into a corresponding well of a multi-well plate; and at least one heat sink configured to warm the inert drying gas upstream of injection into the wells; This includes starting the heat sink before the inert gas flow (known as idle thermal operation), warming the heat sink to the required temperature based on the required flow and nozzle temperature to make the equipment ready for immediate use (using preheated equipment), or starting heating as soon as gas flow is enabled (immediate start operation).

[0028] This method avoids the drawbacks of the prior art, where the inert gas flow must first heat the manifold, tubes, and adapter plate during the start-up process, and then be gradually initiated to obtain the correct gas temperature from the nozzle. As a result, the present invention provides a rapid heat-up time from the cryogenic system to the operating temperature, resulting in faster evaporation than the prior art. Another advantage of this method is that the required gas volume can be reduced, since the gas flow provides immediate and efficient evaporation.

[0029] The inert gas may be any gas that does not undergo a chemical reaction under the given conditions, such as nitrogen gas, or any other gas that is inert to the solvent being evaporated.

[0030] The evaporator provided in this method may be any embodiment of the evaporator presented herein according to the present invention. [Brief explanation of the drawings]

[0031] [Figure 1] 1 is an example of an evaporator according to the present invention, showing how the heating element is integrated into the manifold. [Figure 2] 2 shows the manifold of FIG. 1 in cross section, with the base element positioned to receive a multiwell plate. DETAILED DESCRIPTION OF THE INVENTION

[0032] Detailed Description of the Invention As can be seen from the above, with reference to FIG. 1, the present invention relates to an evaporator 1 comprising a plate holder 2. The plate holder 2 is configured to hold a plate containing wells or cavities, such as a multiwell plate, so that its horizontal upper surface is positioned vertically at a desired height. In this regard, as those skilled in the art will understand, the desired height is the height at which each well or cavity is positioned so as to contact a nozzle that provides a flow of inert gas into said well or cavity during evaporation. As is well known, such inert drying gas can be configured to be injected into the wells or cavities at any suitable angle, depending on known variables such as the desired degree of evaporation required, the nature of the solvent being evaporated, the speed and efficiency of the process, etc. Other modes of gas flow are possible, such as those provided by angled and / or otherwise offset nozzles.

[0033] Advantageously, the nozzle directs the gas flow at an angle to provide turbulence within said well or cavity.

[0034] Additionally, at least one gas-heated injection manifold 3 is positioned above the plate holder 2 and has at least one injection nozzle 4 positionable at approximately the desired height. As will be appreciated by those skilled in the art, most evaporation processes are carried out using multiple nozzles 4, advantageously as many nozzles as there are wells in the microwell plate. Thus, each nozzle 4 is adapted to inject an inert drying gas into a corresponding well of the multiwell plate.

[0035] To improve the evaporation process, the inert drying gas is warmed before being injected from the nozzles into the corresponding wells. This is obtained according to the invention by one or more heating elements 5 configured to warm the inert drying gas upstream of its injection into said wells. More specifically, according to the invention, in the manifold 3, said at least one heating element is a heat sink 6 integrated into said at least one manifold 3.

[0036] 2, the heat sink 6 integrated into the manifold 3 is clearly visible in cross section. The heat sink is advantageously a pin cooler, such as a straight or flared pin cooler. Pin coolers suitable for use in accordance with the present invention are readily available from commercial sources.

[0037] Furthermore, in FIG. 2 it is clearly shown where the multiwell plate (7) is located.

Claims

1. An evaporator (1), comprising: a plate holder (2) arranged to firmly hold a multi-well plate so that its horizontal upper surface is positioned vertically at a desired height; at least one gas-heated injection manifold (3) disposed above the plate holder (2) and having at least one injection nozzle (4) positionable at approximately the desired height, each nozzle (4) adapted to inject an inert dry gas into a corresponding well of the multi-well plate; one or more heating elements (5) configured to warm the inert dry gas upstream of injection into the well, and at least one heating element is a heat sink (6) integrated into said at least one gas heating inlet manifold (3).

2. 10. The evaporator of claim 1, wherein at least the temperature of the heat sink is maintained within a predetermined range or at a predetermined temperature based on the required flow and nozzle temperature using open loop control without feedback from the actual nozzle temperature.

3. 3. The evaporator of claim 1, wherein the heat sink is a pin cooler.

4. An evaporator according to any one of claims 1 to 3, which is placed in a system and connected online with one or more downstream analytical devices.

5. 5. The evaporator of claim 4, wherein the analytical device is selected from the group consisting of a gas chromatograph, a liquid chromatograph, a mass spectrometer, and a device for flow injection analysis.

6. 1. A method for evaporating a solvent using a preheated inert gas, comprising: providing an evaporator comprising: a plate holder; at least one gas injection manifold disposed above the plate holder and having at least one injection nozzle, each nozzle adapted to inject an inert drying gas into a corresponding well of a multi-well plate; and at least one heat sink integrated into the at least one gas injection manifold, configured to warm the inert drying gas upstream of injection into the wells; and starting the heat sink prior to inert gas flow or warming the heat sink to the required temperature based on the required flow and nozzle temperature to make the equipment ready for use or commencing heating as soon as gas flow is enabled.

7. The method of claim 6 , wherein the vaporizer is connected online to one or more downstream analytical devices.

8. 8. The method according to claim 6, wherein the inert gas is nitrogen gas.

9. The method according to any one of claims 6 to 8, wherein an evaporator according to any one of claims 1 to 5 is used.

10. Use of a pin cooler for preheating gas in a laboratory evaporator according to any one of claims 1 to 5.

11. Use of the evaporator according to any one of claims 1 to 5 or the method according to any one of claims 6 to 10 for solvent exchange of a liquid sample or drying of an analyte.

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