Thiocarbamate-based indicator detection of ozone

Abstract

One embodiment provides a method for measuring ozone in a sample, the method comprising: preparing a thiocarbamate-based indicator; introducing a thiocarbamate-based indicator into the sample wherein the sample contains an amount of ozone and the introduction causes a fluorescence change in the solution; and measuring the amount of ozone in the sample by measuring a change in the fluorescence intensity. Other aspects are described and claimed.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Patent Application Serial No. 63 / 343,808, filed on May 19, 2022, entitled “Thiocarbamate-Based Indicator Detection of Ozone,” the contents of which are incorporated herein by reference. Background Art

[0003] The present application relates generally to measuring ozone in aqueous or liquid samples, and more particularly to measuring ozone using thiocarbamate-based indicators.

[0004] Ensuring water quality is critical in a variety of industries such as pharmaceuticals and other manufacturing fields. Additionally, ensuring water quality is critical to the health and well-being of humans, animals, and plants that rely on water to survive. One element that is commonly measured is ozone. Ozone can be controlled to make water safe for humans, animals, and aquatic life. Therefore, it is critical to detect the presence and concentration of ozone in water, food materials, or other liquid solutions. Summary of the invention

[0005] In summary, one embodiment provides a method for measuring ozone in a sample, the method comprising: preparing a thiocarbamate-based indicator; introducing the thiocarbamate-based indicator into a sample, wherein the sample contains a certain amount of ozone and the introduction causes a fluorescence change in the solution; and measuring the amount of ozone in the sample by measuring the change in fluorescence intensity.

[0006] Another embodiment provides a method for measuring ozone in a sample, the method comprising: preparing a thiocarbamate-based indicator; introducing the thiocarbamate-based indicator into a sample, wherein the sample contains a certain amount of ozone and the introduction causes a fluorescence change in the solution; adding potassium iodide to the sample, wherein the potassium iodide accelerates the reaction rate between the thiocarbamate-based indicator and ozone and causes a fluorescence change in the sample; and measuring the amount of ozone in the sample by measuring the change in fluorescence intensity.

[0007] Another embodiment provides a measuring device for measuring ozone in a sample, the measuring device comprising: a thiocarbamate-based indicator; at least one measuring chamber; a processor; and a memory storing instructions executable by the processor for:

[0008] The thiocarbamate indicator is introduced into a sample, wherein the sample contains a certain amount of ozone; potassium iodide is added to the sample, wherein the potassium iodide accelerates the reaction rate between the thiocarbamate indicator and ozone and causes a fluorescence change of the sample; and the amount of ozone in the sample is measured by measuring the fluorescence change of the sample.

[0009] The foregoing is a summary and thus may contain simplifications, generalizations, and omissions of detail; consequently, those skilled in the art will appreciate that this summary is illustrative only and is not intended to be in any way limiting.

[0010] For a better understanding of the embodiments, together with other and further features and advantages thereof, reference is made to the following description taken in conjunction with the accompanying drawings.The scope of the invention will be indicated in the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 A flow chart of an exemplary ozone measurement system is shown for a sample.

[0012] Figure 2 An example of a reaction scheme of a thiocarbamate-based indicator for detecting ozone is shown.

[0013] Figure 3 Exemplary ozone calibration curves using thiocarbamate-based indicators from two operators are shown.

[0014] Figure 4A Exemplary data of ozone measurement results using a thiocarbamate-based indicator are shown.

[0015] Figure 4B Additional exemplary data of ozone measurements using UV-Vis detection are shown.

[0016] Figure 5 An example of a computer circuit system is shown. DETAILED DESCRIPTION

[0017] It will be readily understood that, in addition to the exemplary embodiments described, the components of the embodiments generally described and illustrated in the drawings herein may be arranged and designed in a variety of different configurations. Therefore, the following more detailed description of the exemplary embodiments as shown in the drawings is not intended to limit the scope of the embodiments, but merely represents exemplary embodiments.

[0018] References throughout this specification to "one embodiment" or "an embodiment" (etc.) mean that a particular feature, structure, or characteristic described with respect to that embodiment is included in at least one embodiment. Thus, the appearances of the phrases "in one embodiment" or "in an embodiment", etc., at various locations throughout this specification do not necessarily all refer to the same embodiment.

[0019] In addition, the described features, structures or characteristics can be combined in any suitable manner in one or more embodiments. In the following description, many specific details are provided to give a comprehensive understanding of the embodiments. However, those skilled in the relevant art will recognize that various embodiments can be implemented without one or more specific details, or using other methods, components, materials, etc. In other cases, well-known structures, materials or operations are not shown or described in detail. The following description is only for illustration, and only some exemplary embodiments are described.

[0020] Conventional methods of ozone measurement in water may have some limitations. For example, ozone measurement may be used to determine water quality. High ozone concentrations may be harmful to animals, humans, and / or plants. Thus, as another example, a user or entity may want the ozone in a body of water to be below a certain threshold, and therefore, the user may measure the ozone to determine whether the amount of ozone is below the threshold.

[0021] One standard for free ozone measurement in water is Hach's AccuVac (available from Hach Company, Loveland CO, USA (AccuVac is a registered trademark of Hach Company in the United States and other countries), which is a bleaching chemistry. These methods result in an amount of color bleaching that is proportional to the ozone concentration. The color resulting from the colorimetric reaction can be measured photometrically, for example, using a spectrophotometer. The amount of ozone can be determined by comparison with a similarly prepared blank vial. The absorbance of the sample reaction vial must be compared to the absorbance of an unreacted blank vial to determine the ozone concentration of the sample reaction vial.

[0022] However, current analyte testing methods have limitations, which are overcome by methods and techniques as described in more detail herein. One limitation of current technology is that they use bleaching chemistry that is disadvantageous to some users and measurement systems. In addition, traditional colorimetry requires the preparation of a separate "blank" vial. The additional steps of preparing a blank vial may introduce errors into the measurement results based on personal skills when preparing a blank. In addition, because traditional colorimetric techniques involve the bleaching of dyes, the time of preparation and the time of measurement may introduce variability in sample readings. In addition, because technology includes the bleaching of dyes, difficulties may arise, because the volume of the starting colorimetric dye may be different in both blank and sample vials, thereby introducing errors into the determination of the amount of the analyte in the sample. This error may cause false positive results or false negative results.

[0023] Therefore, one embodiment provides a system and method for measuring ozone in a sample. Samples can be taken from a certain volume of liquid such as a holding tank, a water source, a food material source, a beverage source, etc. The sample may not contain other oxidants. In one embodiment, the method can detect ozone in a concentration range of about 0 to 1.5 ppm (parts per million). In one embodiment, the method can use fluorescence determination. The indicator that gives the fluorescent signal can be a thiocarbamate derivative. The thiocarbamate derivative can be a derivative of 7-hydroxycoumarin. The thiocarbamate can be an umbelliferyl thiocarbamate. Additives can be added to the method. The additive can speed up the completion time of the reaction. The additive can be potassium iodide (KI). In one embodiment, fluorescence can be related to the detection of ozone. In one embodiment, fluorescence intensity or fluorescence change can be related to ozone in the sample. A buffer, such as a phosphate buffer, can be added. In one embodiment, the pH of the solution can be adjusted to activate a reporter molecule or an indicator molecule. The pH can be adjusted to about pH 4.0 to about 8.5.

[0024] The illustrated exemplary embodiments will be best understood by referring to the accompanying drawings.The following description is for illustration only and describes only certain exemplary embodiments.

[0025] Reference Figure 1, an exemplary system and method for detecting ozone in a sample is shown. In one embodiment, a thiocarbamate-based indicator can be prepared. The thiocarbamate-based indicator can be introduced into a sample containing ozone. In one embodiment, an additive can be added. The additive can be potassium iodide (KI). The additive can speed up the reaction. In another embodiment, no additive or KI may be added. In one embodiment, the thiocarbamate-based indicator in the presence of ozone can cause a change in the fluorescence intensity of the thiocarbamate-based indicator. The change in fluorescence intensity can be related to the concentration of ozone in the solution or sample.

[0026] At 101, in one embodiment, a thiocarbamate-based indicator may be prepared. The thiocarbamate-based indicator may be a thiocarbamate derivative of hydroxycoumarin. In one embodiment, the thiocarbamate-based indicator may be methylumbelliferylthiocarbamate or umbelliferylthiocarbamate. Figure 2 , showing an exemplary reaction of a thiocarbamate-based indicator. In one embodiment, the thiocarbamate-based indicator can detect ozone in the range of 0 to 1.5 mg / L. This range is exemplary, for example, the range can be determined based on the need to control ozone to a level suitable for water treatment.

[0027] At 102, in one embodiment, a thiocarbamate indicator can be introduced into a sample. The sample can contain ozone or a certain amount of ozone. The solution can be a sample, which can include samples from natural water bodies, holding tanks, processing tanks, pipelines, water systems, a certain volume of liquid used for food preparation, etc. The solution can be in a continuous flow state, a static volume of liquid, or any combination thereof. In one embodiment, the sample can be introduced into a thiocarbamate indicator (e.g., a test chamber of a measuring device). Introducing the sample into the measuring device can include placing or introducing the sample into the test chamber manually or using mechanical means (e.g., gravity flow, pumps, pressure, fluid flow, etc.) by the user. For example, a water sample for ozone testing can be introduced into a measuring chamber or a test chamber using a pump. In one embodiment, a valve, etc. can control the inflow and outflow of a solution to or from one or more chambers (if present).

[0028] Additionally or alternatively, the measuring device may be present in or introduced into a certain volume of sample.Then the measuring device is exposed to the certain volume of sample, and the measuring device can measure there.The system can be a flow-through system that automatically mixes and measures solution and / or reagent.As discussed in more detail herein, once sample contacts the measuring system, the system can measure the ozone of the sample or the fluorescence variation of the sample.In one embodiment, the measuring device may include one or more chambers in which one or more method steps may be performed.

[0029] At 103, in one embodiment, an additive may be added to the sample. The additive may be an optional step. The additive may be potassium iodide (KI). The additive may speed up the reaction. The additive may speed up the reaction of the thiocarbamate indicator and ozone. The additive may shorten the reaction time and / or speed up the reaction of the thiocarbamate indicator and ozone by approximately 30 seconds. In one embodiment, the pH of the solution may be controlled. Additionally or alternatively, ozone may be added to the solution. Ozone may be added to the sample using an ozone generator, or it may be produced by other processes. In one embodiment, the thiocarbamate indicator in the presence of ozone may "turn-on" the fluorescent properties of the thiocarbamate indicator.

[0030] In one embodiment, the pH of the solution can be adjusted. For example, the pH can be adjusted or titrated to a pH in the range of about 4.0 to about 8.5. The thiocarbamate indicator concentration can be about 5 to 40 micromolar (μM). The indicator concentration can be adjusted based on the ozone concentration in the sample. In one embodiment, a buffer can be added. The buffer can be a phosphate buffer. The phosphate buffer concentration can be about 75 mM. In one embodiment, potassium iodide can be about 30 to 40 μM. The approximate detection range of ozone is 0 to 1.5 mg / L.

[0031] In one embodiment, a cosolvent can be added to the sample. The cosolvent can make the thiocarbamate-based indicator more soluble. The cosolvent can be a low molecular weight molecule. In one embodiment, the cosolvent can include: isopropanol, ethanol, polyethylene glycol, polyethylene glycol dimethyl ether, polyethylene glycol methyl ether, etc. In one embodiment, the cosolvent can be a mixture of the cosolvents considered. The use concentration of the cosolvent can be less than or equal to 10% of the sample volume.

[0032] At 104, in one embodiment, the systems and methods can determine whether ozone concentration can be determined. In one embodiment, the presence of ozone in the sample can cause an increase in the fluorescence intensity of the thiocarbamate-based indicator. Examples of this increase in fluorescence intensity of the thiocarbamate-based indicator and a dose response curve can be found at Figure 3 . An embodiment of relative fluorescence units (RFU) is plotted against ozone concentration (mg / L). Data from two operators are shown. The operator can be a laboratory person or a technician. The ozone concentration shown is 0 to 0.839 mg / L. The experimental conditions may include: generating ozone using an ozone generator at room temperature or cooling the sample to approximately 0 to 5 degrees Celsius, stirring the sample, pretreating the pipette tip by placing it into the ozonated sample, and measuring the absorbance using a 10 cm cell. These conditions are exemplary and can be changed based on the conditions. In one embodiment, a thiocarbamate-based indicator can be used at a final concentration of 5 to 40 micromolar (μM).

[0033] The measured absorbance can be correlated to the concentration or amount of ozone in the sample or water. This correlation can be based on the UV-Vis measurement results of ozone. This can be used as a reference measurement. The same aliquot can then be used in a 16 cm cell with buffer and indicator. Depending on the ozone concentration, the sample can be diluted with deionized water. The measurement can use a HachDR1300 FL (available from Hach Company, Loveland CO, USA) instrument to measure the RFU value or concentration relative to the UV-Vis value. Operator refers to the laboratory personnel performing the experiment. Reference Figure 4A , in one embodiment, exemplary data for measuring ozone concentration using a thiocarbamate-based indicator is shown. Repeated operation of different operators for different ozone concentrations is shown, demonstrating the performance and accuracy of the thiocarbamate-based indicator as an ozone measurement method. In one embodiment, the excitation wavelength can be between 320 and 385 nanometers (nm). In one embodiment, the emission wavelength can be between 420 and 470 nm. Reference Figure 4B In one embodiment, the concentration of ozone is calculated using Beer's Law using a 10 cm path length and a known molar excitation coefficient at a wavelength of 258 nm.

[0034] A phosphate buffer may be added. A solution of a thiocarbamate indicator may be prepared in isopropanol and added to the sample, keeping the volume of isopropanol less than or equal to 10% of the sample volume. In one embodiment, citrate may be added as an additive. The concentration of citrate may be 15 mM. Citrate may prevent the formation of metal phosphates by complexation. Potassium iodide may be added as a catalytic additive.

[0035] Thus, the fluorescence intensity of the ozone-containing solution can be related to the intensity or changes in intensity of the sample or aqueous solution. Fluorescence curves can be generated for various concentrations, for different thiocarbamate-based indicators, for any different conditions that may affect the absorption or fluorescence values ​​(e.g., temperature, sample content, turbidity, viscosity, measurement equipment, aqueous sample chamber, etc.), etc.

[0036] Alternatively or additionally, ozone measurements may be made at periodic intervals set by the user or at a pre-programmed frequency in the device. Real-time data may be obtained with the device, requiring little human involvement during the measurement process. Cleaning of the fluorescence chamber may be required at unspecified intervals. Programmed calibration curves may be input into the device.

[0037] The chamber, container, pool, chamber, etc. can hold a sample, at least one thiocarbamate-based indicator, and related reagents such as buffers and / or additives. The device can include one or more reagent bottles containing necessary reagents. The reagents contained in one or more bottles can be pump-fed or gravity-fed. The flow of reagents can be metered to ensure that the appropriate volume is delivered to the measuring cell. The sample can be fed through a pressurized inlet, container, etc. The sample can be introduced into the measuring chamber by pump feeding or gravity feeding. The sampling device can be connected in series or in parallel with the aqueous stream. The device can have a system that ensures the appropriate mixing of aqueous samples, thiocarbamate-based indicators, and related reagents.

[0038] Fluorescence intensity or ozone concentration can be output results in the form of display, printing, storage, audio, tactile feedback, etc. on the device. Alternatively or additionally, the output results can be sent to another device by wired, wireless, optical fiber, Bluetooth®, near field communication, etc. An embodiment can use an alarm to warn of measurement results or concentrations outside acceptable levels. An embodiment can use a system to shut off water output, or shunt water from a source with unacceptable analyte levels. For example, the analyte measuring device can use a relay connected to an electric valve, etc.

[0039] At 106, in one embodiment, if the concentration of ozone cannot be determined, the system may continue to measure ozone, changes in fluorescence intensity, and / or fluorescence intensity. Additionally or alternatively, the system may output an alarm, log an event, etc.

[0040] If the concentration of ozone can be determined, then at 105, the system can provide a measurement of the ozone concentration. The system can be connected to a communication network. The system can issue an alarm to a user or a network. This alarm can be made regardless of whether the ozone measurement result is determined. The alarm can be in the form of sound, visual, data, storage of data to a memory device, sending output through a connected system or wireless system, printout, etc. The system can record information such as measurement location, corrective action, geographic location, time, date, number of measurement cycles, etc. The alarm or log can be automated, which means that the system can automatically output whether correction is required. The system can also have associated alarms, limits, or predetermined thresholds. For example, if the ozone concentration reaches a threshold. The alarm or log can be analyzed in real time, stored for later use, or any combination thereof.

[0041] Therefore, the embodiments described herein represent a technical improvement to conventional ozone measurement techniques. Using the techniques described herein, one embodiment can use a thiocarbamate-based indicator to measure ozone in a solution. This is in contrast to methods having the above limitations. Such techniques provide a faster and more accurate method for measuring ozone in an aqueous or liquid solution. Therefore, the embodiments described herein represent a technical improvement to precise ozone measurement in a sample. Using the techniques described herein, one embodiment can use a method and apparatus for measuring ozone concentration. This is in contrast to conventional methods having the above limitations.

[0042] Although various other circuits, circuit systems or components may be used in the information processing device, with respect to the apparatus for measuring ozone according to any of the embodiments described herein, Figure 5 An example is shown in . The device circuit system 10' may include a measurement system based on a created chip design, for example, a specific computing platform (e.g., mobile computing, desktop computing, etc.). Software and one or more processors are combined in a single chip 11'. It is well known in the art that a processor includes an internal arithmetic unit, registers, cache memory, bus, I / O ports, etc. The internal bus, etc. depends on different vendors, but basically all peripheral devices (12') can be connected to a single chip 11'. The circuit system 10' combines the processor, memory control, and I / O controller hub into a single chip 11'. In addition, this type of system 10' generally does not use SATA or PCI or LPC. For example, common interfaces include SDIO and I2C.

[0043] There are one or more power management chips 13', such as a battery management unit (BMU), which manages power supplied, for example, by a rechargeable battery 14' (which can be recharged by connecting to a power source (not shown)). In at least one design, a single chip such as 11' is used to provide BIOS-like functions and DRAM memory.

[0044] The system 10' typically includes one or more of a WWAN transceiver 15' and a WLAN transceiver 16' for connecting to various networks such as radio communication networks and wireless Internet devices (e.g., access points). In addition, devices 12' are generally included, such as transmit and receive antennas, oscillators, PLLs, etc. The system 10' includes input / output devices 17' for data input and display / rendering (e.g., a computing location located away from the single beam system that is easily accessible to the user). The system 10' typically also includes various memory devices, such as flash memory 18' and SDRAM 19'.

[0045] It can be understood from the foregoing that the electronic components of one or more systems or devices may include, but are not limited to: at least one processing unit, memory, and a communication bus or communication device connecting each element (including memory) to the one or more processors. The system or device may include or access various device-readable media. The system memory may include device-readable storage media in the form of volatile and / or non-volatile memory (such as read-only memory (ROM) and / or random access memory (RAM)). By way of example and not limitation, the system memory may also include an operating system, application programs, other program modules, and program data. The disclosed system can be used to measure ozone on a sample in one embodiment.

[0046] Those skilled in the art will appreciate that various aspects may be implemented as systems, methods, or device program products. Thus, various aspects may take the form of a complete hardware implementation or an implementation including software, which may all be collectively referred to herein as a "circuit," "module," or "system." Additionally, various aspects may take the form of a device program product embodied in one or more device-readable media containing device-readable program code.

[0047] It should be noted that the various functions described herein can be implemented using instructions stored on a device-readable storage medium (such as a non-signal storage device), where the instructions are executed by a processor. In the context of this article, a storage device is not a signal, and "non-transient" includes all media except signal media.

[0048] The program code for implementing the operation can be written in any combination of one or more programming languages. The program code can be executed completely on a single device, partially on a single device, as an independent software package, partially on a single device and partially on another device or completely on other devices. In some cases, the device can be connected by any type of connection or network (including local area network (LAN) or wide area network (WAN)), or can be connected by other devices (for example, by using the Internet of an Internet service provider), by wireless connection (for example, near field communication) or by hard wire connection (such as by USB connection).

[0049] Exemplary embodiments are described herein with reference to the accompanying drawings, which illustrate exemplary methods, devices, and products according to various exemplary embodiments. It is to be understood that actions and functions can be implemented at least in part by program instructions. These program instructions can be provided to a processor of an apparatus (e.g., a handheld measuring device) or other programmable data processing apparatus to produce a machine so that the instructions executed by the processor of the apparatus implement specified functions / actions.

[0050] It should be noted that the values ​​provided herein should be interpreted to include equivalent values ​​indicated by the use of the term “about.” Equivalent values ​​will be apparent to one of ordinary skill in the art, but at least include values ​​obtained by ordinary rounding of the last significant digit.

[0051] The present disclosure has been provided for illustration and description, but is not intended to be exhaustive or limiting. Various changes and variations will be apparent to those of ordinary skill in the art. Exemplary embodiments are selected and described to explain principles and practical applications, and to enable those of ordinary skill in the art to understand the disclosure of multiple embodiments with various changes suitable for the intended specific use. Therefore, although exemplary embodiments illustrated have been described herein with reference to the accompanying drawings, it should be understood that this description is not limiting, and that various other changes and variations may be implemented therein by those skilled in the art without departing from the scope and spirit of the present disclosure.

Claims

1. A method for measuring ozone in a sample, the method comprising: preparing a thiocarbamate-based indicator; introducing the thiocarbamate-based indicator into a sample, wherein the sample contains an amount of ozone, and the introduction causes a change in the fluorescence of the solution; and The amount of ozone in the sample is measured by measuring the change in fluorescence intensity.

2. The method of claim 1, wherein the thiocarbamate-based indicator comprises a thiocarbamate derivative of hydroxycoumarin.

3. The method according to claim 2, wherein the thiocarbamate-based indicator is a derivative of 7-hydroxy-coumarin.

4. The method according to claim 1, further comprising: The sample is titrated to a pH in the range of about 4.0 to about 8.

5.

5. The method according to claim 1, further comprising: Phosphate buffer was added. The method according to claim 1 , wherein the amount of ozone is in the range of 0 to 1.5 mg / L. The method of claim 1 , wherein the fluorescence intensity is related to the concentration of ozone in the sample.

8. The method of claim 1, wherein the sample comprises water from a beverage substance system.

9. The method according to claim 1, further comprising: Add co-solvent.

10. The method of claim 9, wherein the co-solvent is selected from the group consisting of isopropanol, ethanol, polyethylene glycol, polyethylene glycol dimethyl ether, and polyethylene glycol methyl ether.

11. A method for measuring ozone in a sample, the method comprising: preparing a thiocarbamate-based indicator; introducing the thiocarbamate-based indicator into a sample, wherein the sample contains an amount of ozone, and the introduction causes a fluorescence change in the solution; adding potassium iodide to the sample, wherein the potassium iodide accelerates the reaction rate between the thiocarbamate-based indicator and ozone and causes a fluorescence change of the sample; and The amount of ozone in the sample is measured by measuring the change in fluorescence intensity.

12. The method of claim 11, wherein the thiocarbamate-based indicator comprises a thiocarbamate derivative of hydroxycoumarin.

13. The method of claim 12, wherein the thiocarbamate-based indicator is a derivative of 7-hydroxy-coumarin.

14. The method according to claim 11, further comprising: The sample is titrated to a pH in the range of about 4.0 to about 8.

5.

15. The method according to claim 11, further comprising: Phosphate buffer was added.

16. The method of claim 11, wherein the amount of ozone is in the range of 0 to 1.5 mg / L.

17. The method of claim 11, wherein the fluorescence intensity is related to the concentration of ozone in the sample.

18. The method of claim 11, wherein the sample comprises water from a beverage substance system.

19. The method according to claim 11, further comprising: Add co-solvent.

20. A measuring device for measuring ozone in a sample, the measuring device comprising: Thiocarbamate-based indicators; at least one measuring chamber; processor; and a memory storing instructions executable by the processor for: introducing the thiocarbamate-based indicator into a sample, wherein the sample contains a certain amount of ozone; adding potassium iodide to the sample, wherein the potassium iodide accelerates the reaction rate between the thiocarbamate-based indicator and ozone and causes a fluorescence change of the sample; and The amount of ozone in the sample is measured by measuring changes in the fluorescence of the sample.

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