Zinc measurement with reduced iron

Abstract

One embodiment provides a method for measuring zinc in an aqueous sample, the method comprising: adding an iron chelating agent to the aqueous sample; chelating an amount of iron in the aqueous sample with the iron chelating agent; and measuring the amount of zinc in the aqueous sample by measuring a change in absorbance intensity of the iron-chelated aqueous sample. Other aspects are described and claimed.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. patent application serial number 17 / 950,415, filed on September 22, 2022, entitled “Iron-Reduced Zinc Measurement,” the contents of which are incorporated herein by reference. Background Art

[0002] The present application relates generally to measuring zinc in a sample, and more particularly to measuring zinc in the presence of iron interferents.

[0003] Ensuring water quality is critical in a variety of industries such as pharmaceuticals and other manufacturing fields. In addition, ensuring water quality is critical to the health and well-being of humans, animals, and plants that rely on water to survive. Metals such as zinc can be measured and monitored. Too much zinc in water can be harmful to humans or animals. For example, zinc can have long-term health effects and can make the water less ideal for consumers or facilities. Zinc can be present from nature or from human activities such as manufacturing. The measurement and reduction of zinc can result in higher costs for water treatment. Therefore, it is critical to detect the presence and concentration of zinc in water or other liquid solutions. Summary of the invention

[0004] In summary, one embodiment provides a method for measuring zinc in an aqueous sample, the method comprising: adding an iron chelator to the aqueous sample; chelating a certain amount of iron in the aqueous sample with the iron chelator; and measuring the amount of zinc in the aqueous sample by measuring a change in the absorbance intensity of the iron-chelated aqueous sample.

[0005] Another embodiment provides a measuring device for measuring zinc in an aqueous sample, the measuring device comprising: a prepackaged module, wherein the prepackaged module contains an iron chelator; a processor; and a memory storing instructions executable by the processor for: adding the iron chelator to the aqueous sample; chelating an amount of iron in the aqueous sample with the iron chelator; and measuring the amount of zinc in the aqueous sample by measuring a change in the absorbance intensity of the iron-chelated aqueous sample.

[0006] Another embodiment provides a method for measuring zinc in an aqueous sample, the method comprising: adding an iron chelator to the aqueous sample, wherein the iron chelator comprises deferoxamine mesylate; chelating an amount of iron in the aqueous sample with the iron chelator; and measuring the amount of zinc in the aqueous sample by measuring a change in absorbance intensity of the iron-chelated aqueous sample.

[0007] 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.

[0008] 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

[0009] Figure 1 A flow chart of an exemplary zinc measurement system is shown.

[0010] Figure 2A Desferrioxamine is shown in one embodiment for use in chelating iron.

[0011] Figure 2B Desferrioxamine is shown binding ferric iron in a hexadentate manner using a 1:1 chelator ratio.

[0012] Figure 3 Exemplary data showing that deferoxamine reduces iron interference in zinc measurements.

[0013] Figure 4 Another exemplary data showing that deferoxamine reduces iron interference in zinc measurements.

[0014] Figure 5 An example of a computer circuit system is shown. DETAILED DESCRIPTION

[0015] 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.

[0016] 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.

[0017] 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 implemented 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.

[0018] Zinc measurement in water or other aqueous samples or solutions is important for a variety of different reasons. For example, zinc measurement can be used to determine water quality. High zinc concentrations may be harmful to animals, humans and / or plants. Therefore, as another example, a user or entity may wish that the zinc in a body of water is below a specific threshold, and therefore, the user can measure zinc to determine whether the amount of zinc is below the threshold. Zinc may be present in the body of water naturally or may be present in the body of water due to human activities such as manufacturing or storage conditions. In addition, for human consumption, medical, industrial, food / beverage or manufacturing applications, it may be necessary to monitor and / or control the level of zinc in the solution.

[0019] Conventional methods for zinc measurement and detection may have limitations discussed herein. For example, conventional methods may use cyanide, cyclohexanone and / or chloral hydrate. Governments may have usage restrictions or waste disposal requirements for these conventional methods. An exemplary method is the Hach 8009-Zinon method. The method can detect zinc (Zn(II)) in the range of 0.010 to 3.0 mg / L. The method has a reaction time of about 3.5 minutes and is measured using a spectrophotometer (620 nm) or a colorimeter (610 nm). However, there are some limitations to the method. First, the presence of excess indicator may interfere with visual inspection. Second, there may be problems using the method in the presence of interferences higher than a given concentration. For example, aluminum higher than 6 mg / L, cadmium higher than 0.5 mg / L, copper higher than 5.0 mg / L, iron (III) higher than 7 mg / L, manganese higher than 5 mg / L, and nickel higher than 5 mg / L may interfere with correct zinc measurement. The above interference levels and interference types are illustrative only, and other concentrations and / or interferences may be included, for example, calcium and magnesium. Third, the method uses hazardous reagents, such as cyanide and / or cyclohexanone.

[0020] Another exemplary method for zinc measurement is the LCK 360 - 4-(2-pyridyl azo) resorcinol method. This method uses a Crack-Set LCW 902 to detect zinc (Zn(II)) in the range of 0.2 to 6.0 mg / L or in the range of 0.24 to 7.2 mg / L. This method has a reaction time of approximately 3.0 minutes. However, there are some limitations to this method. First, this method is used for very small sample amounts, such as 0.2 mL. Second, using this method in the presence of interferences may be problematic. Interferences include sulfate, chloride, sodium, potassium, calcium, nitrate, magnesium, iron (II and III), tin, nickel, copper, chromium, carbonate, cobalt and / or lead. Third, this method uses hazardous reagents, such as cyanide and / or chloral hydrate. Chloral hydrate may be particularly problematic due to its listing as a controlled substance in the United States.

[0021] Another example of zinc measurement is the Zinc Palintest method. This method reacts zinc with 2-carboxy-2'-hydroxy-5'-sulfophenylazo-benzene monosodium salt (Zincon) in an alkaline solution, resulting in an orange to blue color based on the zinc concentration. The color produced indicates the zinc concentration and is measured using a Palintest Photometer. A calibration procedure can be used with ethylenediaminetetraacetic acid (EDTA) for those samples containing zinc. EDTA destroys the colored complexes formed with zinc. This is considered a bleaching method that is not conducive to zinc detection.

[0022] Current methods, systems and kits for measuring zinc using the above-mentioned methods using spectrophotometric or colorimetric tests are limited because hazardous reagents are required to reduce interferents, which may introduce significant errors in zinc measurements. In addition, hazardous or controlled reagents make obtaining reagents and handling difficult. In addition, Palintest uses 2-carboxy-2'-hydroxy-5'-sulfophenylazo-benzene monosodium salt to simultaneously detect zinc (II) and copper (II). However, this test measures zinc (II) and copper (II) (if present), then uses EDTA to chelate the zinc (II) and leave only the copper (II)-2-carboxy-2'-hydroxy-5'-sulfophenylazo-benzene monosodium salt complex present. What is needed is an accurate method for measuring zinc in water samples with fewer interference issues and less hazardous reagents.

[0023] In addition, conventional methods have used bleaching chemistry that is disadvantageous to some uses and measurement systems. In addition, traditional colorimetry may need to prepare a separate "blank" vial. The additional step 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 bleaching of dyes, the time of preparation and the time of measurement may introduce variability in sample readings. In addition, because technology includes bleaching of dyes, difficulties may arise, because the volume of the initial 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 lead to wrong analyte measurement results.

[0024] Since iron ions are common in various water matrices, and selective reduction of iron in the presence of other metals may be difficult, a method for measuring zinc in the presence of iron interferences is needed. For zinc CHEMKEY® pre-packaged modules (available from Hach Company, Loveland CO, USA) (CHEMKEY is a registered trademark of Hach Company in the United States and other countries), the addition of deferoxamine mesylate can selectively reduce iron interference to at least 1.0 mg / L (in terms of Fe), while only causing an overall sensitivity loss of ~5%, and having no negative impact on accuracy. Deferoxamine can be used for other product applications (e.g., monochloramine) where iron is a significant interference in spectrophotometry.

[0025] Therefore, one embodiment provides a system and method for measuring zinc in the presence of an interfering substance. In one embodiment, the interfering substance can be iron. In one embodiment, no harmful reagents such as cyanide are used. In one embodiment, the colorimetric detection method does not use bleaching chemistry. In one embodiment, the colorimetric method can be used for zinc in an aqueous sample or solution. The aqueous sample can contain a certain amount of zinc to be measured. The aqueous sample can be buffered. The buffering can be to make the pH at or near 8.2. The aqueous sample can be chelated. In one embodiment, an iron chelator can be used. The iron chelator can be deferoxamine or deferoxamine mesylate. In one embodiment, the amount of zinc can be measured in response to the iron chelator. In one embodiment, the amount of zinc in the aqueous sample can be measured by measuring the change in the absorbance intensity of the aqueous sample chelated by iron. In one embodiment, the change in absorbance intensity is proportional to the concentration of the amount of zinc in the aqueous sample. In one embodiment, the iron chelator can be introduced into the aqueous sample in a form selected from the group consisting of the following: solution, powder and pre-packaged module such as CHEMKEY®. In one embodiment, the aqueous sample may include interferents, which may include: iron, monochloramine, aluminum, copper, manganese, calcium, magnesium, nickel, cobalt, etc. In one embodiment, the aqueous sample may be a water sample for quality inspection. The system and method may use colorimetric and / or spectrophotometric measurements.

[0026] 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.

[0027] Reference Figure 1 , an exemplary system and method for measuring zinc in an aqueous sample, sample or solution is shown. In one embodiment, the aqueous sample can be pH adjusted. In one embodiment, an iron chelator can be added to the aqueous sample. Different zinc concentrations can result in different colorimetric intensities after corresponding chelation, and the change in colorimetric intensity can be associated with the concentration of zinc in the aqueous sample.

[0028] At 101, in one embodiment, a sample or aqueous sample may be prepared. In one embodiment, the sample may be placed in a solution, aqueous sample, water sample, etc. The sample may be added to a chamber, container, etc. in the form of a powder, liquid, or pre-packaged module such as CHEMKEY® along with other components. The sample and / or components may be added manually or using an automated system.

[0029] In one embodiment, the aqueous sample can be buffered. The resulting pH can be approximately equal to, above or below a pH of 8.2. In one embodiment, the pH value can be selected to minimize interference. For example, the pH can be selected based on the concentration and / or composition of the interference. Possible interferences can include iron, aluminum, copper, manganese, calcium, magnesium, nickel, cobalt, etc. The aqueous sample can have interferences that can contain one or more different concentrations, or no interference at all.

[0030] Aqueous samples can include samples from natural water bodies, holding tanks, processing tanks, pipelines, etc. The solution can be in a continuous flow state, a static volume of liquid, or any combination thereof. In one embodiment, the solution can be introduced into a reducing agent or buffer (e.g., a test chamber of a measuring device). In one embodiment, the measuring device can be a desktop device, a field device, or a handheld device. The handheld device can have advantages such as lower cost, portability, and field use. Introducing the solution into the measuring device can include placing or introducing the solution 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 zinc measurement can be introduced into a measurement or test chamber using a pump. In one embodiment, a valve, etc. can control the inflow and outflow of the solution to or from one or more chambers (if present).

[0031] Chambers, containers, units, chambers, etc. can hold aqueous samples and related reagents, such as reducing agents, buffers, and / or iron chelators. Various reagents can be added to the aqueous sample in the form of powders, liquids, pre-packaged modules such as CHEMKEY® pre-packaged modules, etc. The device can include one or more reagent bottles containing necessary reagents. The reagents contained in the 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 aqueous sample can be fed through a pressurized inlet, container, etc. The aqueous sample can be introduced into the measuring chamber by pump-fed or gravity-fed. 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 the aqueous sample with the reducing agent, buffer, and / or zinc chelator.

[0032] Additionally or alternatively, the measuring device can be present in or introduced in a certain volume of solution.Then the measuring device can be exposed to the water sample of this certain volume, where it can be measured.The system can be a flow-through system that automatically mixes and measures water sample and / or reagent.As discussed in more detail herein, once sample contacts with the measuring system, the system can measure the amount of zinc or zinc in the sample.In one embodiment, the measuring device can include one or more chambers in which the one or more method steps can be performed.

[0033] At 102, in one embodiment, an iron chelator may be added to the aqueous sample. The iron chelator may be added after the reducing agent and / or the buffer. In one embodiment, the iron chelator may be deferoxamine mesylate (see Figure 2A Deferioxamine is a chelating agent that binds to ferric iron in a hexadentate manner with a 1:1 chelation ratio (see Figure 2B ). An iron chelator may be added to the chamber, container or measuring chamber. The iron chelator may be added using a manual or automated method in a measured amount corresponding to the volume of the aqueous sample containing zinc. Deferoxamine mesylate may reduce iron interference to at most about 1 mg / L. Deferoxamine mesylate may have a very slight loss of sensitivity (~5%) for zinc readings. Other iron chelators are also disclosed, such as TPTZ, 1,10-phenanthroline, monohydrate, ferrozine sodium salt, ferene, bathophenanthroline, sodium diethylthiocarbamate, bathophenanthroline disulfonic acid disodium salt hydrate, 3-nitrosalicylic acid bathocuproine disulfonicacid disodium salt hydrate, deferoxamine methanesulfonate, 3-(2-pyridyl)-5,6-di(2-furyl)-1,2,4-triazine-5′,5′′-disulfonic acid disodium salt, and the like.

[0034] At 103, in one embodiment, the system and method can measure the amount of zinc in the solution by measuring the change in absorbance intensity caused by the reaction of zinc with the chelating agent. In one embodiment, the presence of zinc in the aqueous solution can cause the absorbance intensity to increase. Therefore, the change in the absorbance of the solution can be proportional to the amount of zinc in the solution. Deferoxamine mesylate can remove iron interference from zinc measurement. Therefore, the measuring device or user can associate the change in the measured absorbance with the amount of zinc in the aqueous sample. In one embodiment, a colorimetric technique can measure the concentration of zinc. For example, the measurement can be a measurement of the absorbance of a colored complex at a certain wavelength. The measurement can include obtaining the ratio of the absorbance collected at multiple wavelengths. Different measuring devices can be used to measure, for example, a portable parallel analyzer (PPA, such as the SL1000 available from Hach Company, Loveland, Co, Colorado), a test strip, a colorimetric analyzer, a spectrophotometer, a pocket colorimeter, an online processing instrument, etc.

[0035] Thus, the absorbance intensity of an aqueous sample containing zinc can be correlated to the concentration of zinc in the aqueous solution. In one embodiment, the amount of absorbance can be proportional to the amount or concentration of zinc in the solution. An absorbance curve can be generated for a range of zinc concentrations, for any different conditions that may affect the absorption or absorbance values ​​(e.g., temperature, sample content, turbidity, viscosity, measurement equipment, aqueous sample chamber, etc.), etc. The absorbance curve can then be used to determine the amount of zinc in the solution.

[0036] Reference Figure 3 , in one embodiment, some exemplary data are shown. In one embodiment, the iron chelator can be in a prepackaged module such as CHEMKEY®. As an example, a control group without deferoxamine can be compared with a 0.1X deferoxamine group. The calibration curve shows that for both the control group without deferoxamine and the 0.1X deferoxamine group, it is closely related in the range of zinc concentrations from 0 to 5 mg / L. Compared with the control group, deferoxamine causes a signal deviation of less than 5%. Note that for the control group without deferoxamine, the presence of 1.25 mg / L zinc with 1.0 mg / L iron interference and without deferoxamine causes a deviation of about 19% between the standard and the measurement result. In other words, iron interference causes the measurement of zinc standards to be incorrect. Compared with the 0.1X deferoxamine group with 1.25 mg / L zinc and 1.0 mg / L iron interference, the percentage deviation drops to 2% (from 19% of the control group without deferoxamine). Deferoxamine can also reduce iron interference measured in cobalt, nickel, etc.

[0037] Reference Figure 4 , in one embodiment, exemplary data for reducing iron interference using deferoxamine are shown. A series of iron concentrations in samples are shown. For example, 0.1X deferoxamine can reduce iron interference to at most about 1.0 mg / L, and at such iron concentrations, if deferoxamine is not used, zinc may not be accurately measured in the presence of iron. The mitigation of iron interference can be controlled using deferoxamine of different concentrations. In other words, compared with the (0.1X deferoxamine) shown, a higher concentration of iron in the sample may require a higher concentration of deferoxamine. Although the iron of 1.0 mg / L in the water sample may be sufficient for drinking water samples, higher levels of iron may be present in industrial waste samples and require more deferoxamine.

[0038] At 104, in one embodiment, the system and method can determine whether the amount of zinc can be measured. For example, the amount of zinc can be measured using colorimetry. The absorbance measurement can be compared to an expected value, a historical value, etc. The zinc measurement using colorimetry can be performed at periodic intervals set by the user or at a pre-programmed frequency in the device. Measuring zinc by the device allows real-time data to be obtained with very little human involvement in the measurement process. In the event that the system outputs an unexpected value, the system can automatically request a remeasurement of the solution or sample.

[0039] The calibration curve of programming can be input into the device for calibrating the measuring device. In one embodiment, the system and method can be tested regularly with known amount of zinc in the sample. The system can then be recalibrated or an error report can be sent for maintenance. In the case where an uncleaned device causes an error or the device needs to be cleaned, the system can implement a cleaning cycle. It may be necessary to clean the colorimetric chamber at unspecified time intervals, after a certain number of measurements, when a user or system requests, etc. In one embodiment, the cleaning cycle of the colorimetric device can be carried out using an automated or manual method.

[0040] At 104, in one embodiment, if the concentration of zinc cannot be determined, the system can continue to measure zinc and / or absorbance signals. Additionally or alternatively, the system can output an alarm, log an event, etc. If the concentration of zinc can be determined, at 105, the system can provide a measurement of the zinc concentration. The measurement that can be output can be an absorbance intensity or a zinc concentration, which is provided to the device in the form of display, printing, storage, audio, tactile feedback, etc. Alternatively or additionally, the output can be sent to another device via wired, wireless, optical fiber, Bluetooth®, near field communication, etc.

[0041] One embodiment can use an alarm to warn of a measurement or concentration outside an acceptable level. One embodiment can use the system to shut off water output, or divert water from a source with an unacceptable zinc level. For example, a zinc measurement device can use a relay connected to an electric valve, etc. The system can be connected to a communication network. The system can issue an alarm to a user or network. This alarm can be performed regardless of whether the zinc measurement result is determined. The alarm can be in the form of sound, vision, 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 zinc concentration reaches a threshold. The alarm or log can be analyzed in real time, stored for later use, or any combination of these situations.

[0042] Absorbance can be measured using different methods. For example, the measurement can be done in a vial using an absorbance of about 620 nm. As another example, absorbance measurements can be performed using a microscopic or mesofluidic device such as a "lab on a chip" type device. Exemplary absorbance data on a mesofluid CHEMKEY® pre-packaged module. Therefore, a measuring device or user can correlate the change in absorbance measured with the amount of zinc in an aqueous sample.

[0043] Thus, the various embodiments described herein represent a technical improvement over conventional zinc measurement techniques. Using the techniques described herein, one embodiment can use a colorimetric indicator to measure zinc in solution. This contrasts with the use of cyanide and / or bleach chemistry, which have the limitations described above. Such techniques provide a faster and more accurate method for measuring zinc in aqueous or liquid solutions while using fewer dangerous or hazardous chemicals or reagents in zinc measurements.

[0044] Although various other circuits, circuit systems or components may be used in the information processing device, with respect to the apparatus for zinc measurement according to any one 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 center 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.

[0045] There are one or more power management chips 13', e.g., a battery management unit (BMU), which manages power supplied, e.g., by a rechargeable battery 14', which can be recharged by connection 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 storage.

[0046] 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'.

[0047] 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 various elements (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 in one embodiment to perform a measurement of zinc in an aqueous sample.

[0048] 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.

[0049] 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.

[0050] 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).

[0051] 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.

[0052] 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.

[0053] The present disclosure has been provided for illustration and description, but is not intended to be exhaustive or limiting. Many changes and variations will be apparent to those of ordinary skill in the art. Exemplary embodiments are chosen 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 a variety of changes suitable for the intended specific use.

[0054] Thus, although the illustrated exemplary embodiments 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 modifications 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 zinc in an aqueous sample, the method comprising: adding an iron chelator to the aqueous sample; chelating an amount of iron in the aqueous sample with the iron chelator; as well as The amount of zinc in the aqueous sample is measured by measuring the change in absorbance intensity of the aqueous sample upon iron chelation.

2. The method of claim 1, wherein the iron chelator comprises deferoxamine mesylate.

3. The method of claim 1, wherein the iron chelator comprises deferoxamine.

4. The method of claim 1, wherein the concentration of the iron chelator is adjusted according to the amount of iron in the aqueous sample.

5. The method of claim 1, wherein the amount of iron in the aqueous sample is at least 1.0 mg / L.

6. The method of claim 1, wherein the change in absorbance intensity is proportional to the concentration of the amount of zinc in the aqueous sample. The method according to claim 1 , wherein the change in absorbance intensity is measured using spectrophotometry. The method according to claim 1 , wherein the change in absorbance intensity is measured using colorimetry.

9. The method of claim 1, wherein the aqueous sample further comprises an amount of monochloramine as an additional interferent.

10. The method of claim 1, wherein the iron chelator is introduced into the aqueous sample in a form selected from the group consisting of a solution, a powder, and a prepackaged module.

11. A measuring device for measuring zinc in an aqueous sample, the measuring device comprising: A prepackaged module, wherein the prepackaged module comprises an iron chelator; processor; and a memory storing instructions executable by the processor for: adding the iron chelating agent to the aqueous sample; chelating an amount of iron in the aqueous sample with the iron chelator; and The amount of zinc in the aqueous sample is measured by measuring the change in absorbance intensity of the aqueous sample upon iron chelation.

12. The device of claim 11, wherein the iron chelator comprises deferoxamine mesylate.

13. The device of claim 11, wherein the iron chelator comprises deferoxamine.

14. The device of claim 11, wherein the concentration of the iron chelator is adjusted according to the amount of iron in the aqueous sample.

15. The device of claim 11, wherein the amount of iron in the aqueous sample is at least 1.0 mg / L.

16. The device of claim 11, wherein the change in absorbance intensity is proportional to the concentration of the amount of zinc in the aqueous sample.

17. The device of claim 11, wherein the change in absorbance intensity is measured using spectrophotometry.

18. The device of claim 11, wherein the change in absorbance intensity is measured using colorimetry.

19. The apparatus of claim 11, wherein the aqueous sample further comprises an amount of monochloramine as an additional interferent.

20. A method for measuring zinc in an aqueous sample, the method comprising: adding an iron chelator to the aqueous sample, wherein the iron chelator comprises deferoxamine mesylate; chelating an amount of iron in the aqueous sample with the iron chelator; and The amount of zinc in the aqueous sample is measured by measuring the change in absorbance intensity of the aqueous sample upon iron chelation.

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