阅读说明：本技术 一种用于快速检测镍离子的方法和装置 (Method and device for rapidly detecting nickel ions ) 是由 张甜 蒋向阳 赵子懿 廖雨潇 皮埃尔 于 2021-09-06 设计创作，主要内容包括：本发明公开一种用于快速检测镍离子的方法和装置。该用于快速检测镍离子的方法的步骤包括：配制显色溶液、制备羧基化细菌纤维素膜、制备镍离子检测器、制备标准比色卡、检测待测样品。本发明的镍离子检测器,能够快速、简便检测镍离子的浓度,检测下限可精确到ppm级,测定全过程仅需1-3分钟,能够现场得到检测结果,提高检测效率；使用过程简便,无需专业人员进行,可满足百姓日常检测需求；本发明的镍离子检测器体积小、易于携带、成本低、检测速度快,使用过程中仅需检测器与标准比色卡,无需其他溶液或大型装置,检测极为方便,不带来环境污染,节能环保,使用方便,有利于技术经济的可持续发展。(The invention discloses a method and a device for rapidly detecting nickel ions. The method for rapidly detecting nickel ions comprises the following steps: preparing a color developing solution, preparing a carboxylated bacterial cellulose membrane, preparing a nickel ion detector, preparing a standard colorimetric card and detecting a sample to be detected. The nickel ion detector can quickly and simply detect the concentration of nickel ions, the lower limit of detection can be accurate to ppm level, the whole detection process only needs 1-3 minutes, the detection result can be obtained on site, and the detection efficiency is improved; the use process is simple and convenient, professional personnel are not needed, and the daily detection requirements of common people can be met; the nickel ion detector disclosed by the invention is small in size, easy to carry, low in cost, high in detection speed, extremely convenient to detect, free from environmental pollution, energy-saving, environment-friendly and convenient to use, only needs the detector and a standard colorimetric card in the using process, does not need other solutions or large devices, and is favorable for sustainable development of technical economy.)

1. A method for rapidly detecting nickel ions is characterized by comprising the following steps:

preparing a color developing solution: preparing a dimethylglyoxime alkaline solution by dimethylglyoxime, sodium hydroxide and deionized water;

preparation of carboxylated bacterial cellulose membranes: performing carboxylation modification on the bacterial cellulose membrane to obtain a carboxylated bacterial cellulose membrane;

preparing a nickel ion detector: immersing the carboxylated bacterial cellulose membrane into the dimethylglyoxime alkaline solution, oscillating at constant temperature, washing, and freeze-drying the washed neutral carboxylated bacterial cellulose to obtain a nickel ion detector;

preparing a standard colorimetric card: a series of concentration gradients at pH 9 were: 0.1, 2, 5, 10, 20 and 50mg/L of standard nickel ion solution is dripped on the nickel ion detector, the color of the nickel ion detector is recorded by photographing, and a standard colorimetric card is manufactured;

detecting a sample to be detected: and dripping the sample to be detected on the other nickel ion detector, and comparing the color of the nickel ion detector with the standard color comparison card to obtain the concentration of the nickel ions in the sample to be detected.

2. The method for rapidly detecting nickel ions according to claim 1, wherein the mass concentration of sodium hydroxide in the dimethylglyoxime alkaline solution is 0.08-0.12 g/L, and the concentration of dimethylglyoxime is 6-14 mmol/L.

3. The method for rapidly detecting nickel ions according to claim 1, wherein the preparation process of the bacterial cellulose membrane comprises the following steps: preparing a acetobacter xylinum culture medium, inoculating strains under an aseptic condition, activating, standing and culturing the strains at a constant temperature to obtain a film, removing residual bacteria by using a sodium hydroxide solution, and washing the film to be neutral by using deionized water to obtain the transparent hydrogel-shaped bacterial cellulose film.

4. The method for rapidly detecting nickel ions according to claim 3, wherein the composition of the culture medium of acetobacter xylinum is as follows: 2 to 3 wt% of glucose, 0.2 to 0.8 wt% of yeast extract, 0.2 to 0.8 wt% of tryptone, 0.08 to 0.15 wt% of citric acid monohydrate, 0.08 to 0.15 wt% of potassium dihydrogen phosphate, 0.2 to 0.8 wt% of disodium hydrogen phosphate dodecahydrate, and the pH is 5 to 7.

5. The method for rapidly detecting nickel ions according to claim 3, wherein the temperature for activating the strains is 28-32 ℃ and the time is 36-72 h; the temperature of the strain constant-temperature static culture is 28-32 ℃, and the time is 7-14 days.

6. The method for rapidly detecting nickel ions according to claim 1, wherein the modification process is specifically as follows: immersing the bacterial cellulose membrane into a mixed solution containing copper ions and hydrogen peroxide, heating and stirring, and then washing with water until the washing solution is neutral to obtain the carboxylated bacterial cellulose membrane.

7. The method for rapidly detecting nickel ions according to claim 6, wherein the concentration of hydrogen peroxide in the mixed solution containing copper ions and hydrogen peroxide is 10-30%, and the concentration of copper ions is 0.018-0.025 g/L; the heating and stirring temperature is 60-65 ℃, and the heating and stirring time is 5-6 h.

8. The method for rapidly detecting nickel ions according to claim 1, wherein the constant temperature oscillation is performed at 30-40 ℃ for 1-2 hours; the freeze drying process comprises the following steps: the washed neutral carboxylated bacterial cellulose is pre-frozen in a refrigerator at the temperature of minus 80 to minus 60 ℃ for 1 to 6 hours, and then is freeze-dried in a freeze dryer for 24 to 72 hours.

9. The method for rapidly detecting nickel ions according to claim 1, wherein the sample to be detected is liquid, and the concentration of nickel ions in the sample to be detected is in a range of 1-50 mg/L.

10. An apparatus for rapidly detecting nickel ions, which comprises the nickel ion detector of any one of claims 1 to 9 and a standard color chart.

Technical Field

The invention relates to the technical field of nickel ion detection, in particular to a method and a device for rapidly detecting nickel ions.

Background

Nickel is one of the essential elements of the human body, and normally contains about 10mg of nickel in an adult. Nickel is also one of the very easy sensitizing elements in daily life, people sensitized by contacting nickel can have symptoms of inflammation, pruritus, papulovesicular dermatitis, eczema and the like, and the occurrence of allergic symptoms can be continued indefinitely. When the nickel is excessively ingested by a human body, vomiting, diarrhea, gastroenteritis and the like can occur, and organ edema, water discharge and degeneration can be caused in severe cases. The nickel in the cigarette can cause irritation and damage to the lung. Therefore, it is indispensable to control and reduce the intake of nickel.

Nickel has good plasticity, corrosion resistance, magnetism and other properties, is widely applied to the fields of steel, nickel alloy, electroplating, batteries and the like, and is widely applied to various military manufacturing industries such as airplanes, radars and the like, electroplating industries and the like. The harm of nickel to human body is not small, and the content of nickel is also clearly limited by the country. The content of nickel is not more than 1.0mg/L, which is clearly specified in national standard GB 8978 + 1996 national Standard for Integrated wastewater discharge of the people's republic of China. The detection of the nickel ion content has important significance in the fields of sewage discharge, environmental detection, agricultural application and food safety. Currently, common methods for detecting heavy metals include: atomic absorption spectrophotometry, ultraviolet spectrophotometer, fluorescence spectrophotometer, inductively coupled plasma mass spectrometer. However, the instrument of the method has larger volume and is inconvenient to carry; the price of single detection is expensive, and the method is not suitable for daily detection; the detection is specialized and is not suitable for daily use of ordinary residents. Therefore, the existing heavy metal detection method cannot meet the detection requirement of rapidness and portability.

Disclosure of Invention

In view of the above, it is desirable to provide a method and an apparatus for rapidly detecting nickel ions, so as to solve the technical problems of the prior art that the detection of nickel ions is costly, long in time, and inconvenient to carry.

The first aspect of the present invention provides a method for rapidly detecting nickel ions, comprising the steps of:

s1, preparing a color developing solution: preparing a dimethylglyoxime alkaline solution by dimethylglyoxime, sodium hydroxide and deionized water;

s2, preparing a carboxylated bacterial cellulose membrane: performing carboxylation modification on the bacterial cellulose membrane to obtain a carboxylated bacterial cellulose membrane;

s3, preparing a nickel ion detector: immersing the carboxylated bacterial cellulose membrane into the dimethylglyoxime alkaline solution, oscillating at constant temperature, washing, and freeze-drying the washed neutral carboxylated bacterial cellulose to obtain the nickel ion detector;

s4, preparing a standard colorimetric card: a series of concentration gradients at pH 9 were: 0.1, 2, 5, 10, 20 and 50mg/L of standard nickel ion solution is dripped on a nickel ion detector, the color of the nickel ion detector is recorded by photographing, and a standard colorimetric card is manufactured;

s5, detecting a sample to be detected: and dripping the sample to be detected on another nickel ion detector, and comparing the color of the nickel ion detector with the standard color comparison card to obtain the concentration of the nickel ions in the sample to be detected.

The second aspect of the invention provides a device for rapidly detecting nickel ions, which comprises a nickel ion detector and a standard colorimetric card.

Compared with the prior art, the invention has the beneficial effects that:

(1) the nickel ion detector can quickly and simply detect the concentration of nickel ions, the lower limit of detection can be accurate to ppm level, the whole detection process only needs 1-3 minutes, the detection result can be obtained on site, and the detection efficiency is improved; the use process is simple and convenient, professional personnel are not needed, and the daily detection requirements of common people can be met;

(2) the nickel ion detector disclosed by the invention is small in size, easy to carry, low in cost, high in detection speed, extremely convenient to detect, free from environmental pollution, energy-saving, environment-friendly and convenient to use, only needs the detector and a standard colorimetric card in the using process, does not need other solutions or large devices, and is favorable for sustainable development of technical economy.

Drawings

FIG. 1 is a standard color chart according to example 1 of the present invention;

FIG. 2 is an SEM image of a detector in example 2 of the present invention;

FIG. 3 is a graph showing pH and absorbance prepared in example 10 of the present invention;

FIG. 4 is a graph showing the relationship between the concentration of a developer and the absorbance in example 11 of the present invention;

FIG. 5 is a graph showing a comparison of absorbance selectivity for various ions in example 12 of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The first aspect of the present invention provides a method for rapidly detecting nickel ions, comprising the steps of:

s1, preparing a color developing solution: preparing a dimethylglyoxime alkaline solution by dimethylglyoxime, sodium hydroxide and deionized water;

s2, preparing a carboxylated bacterial cellulose membrane: performing carboxylation modification on the bacterial cellulose membrane to obtain a carboxylated bacterial cellulose membrane;

s3, preparing a nickel ion detector: immersing the carboxylated bacterial cellulose membrane into the dimethylglyoxime alkaline solution, oscillating at constant temperature, washing, and freeze-drying the washed neutral carboxylated bacterial cellulose to obtain the nickel ion detector;

s4, preparing a standard colorimetric card: a series of concentration gradients at pH 9 were: 0.1, 2, 5, 10, 20 and 50mg/L of standard nickel ion solution is dripped on a nickel ion detector, the color of the nickel ion detector is recorded by photographing, and a standard colorimetric card is manufactured;

s5, detecting a sample to be detected: and dripping the sample to be detected on another nickel ion detector, and comparing the color of the nickel ion detector with the standard color comparison card to obtain the concentration of the nickel ions in the sample to be detected.

According to the invention, the surface-OH of the bacterial cellulose is oxidized into-COOH by modifying the bacterial cellulose through cationic carboxylation, and the content of carboxyl in the bacterial cellulose is increased to increase the hydrophilic performance of the bacterial cellulose; meanwhile, due to the electrostatic action, the enrichment of nickel ions on the surface of the carboxylated bacterial cellulose is accelerated, the detection lower limit and the detection precision are improved, and the detection effect is good.

In step S1, in the dimethylglyoxime alkaline solution, the mass concentration of sodium hydroxide is 0.08-0.12 g/L, and the concentration of dimethylglyoxime is 6-14 mmol/L; the temperature during preparation is 20-45 ℃.

In some embodiments of the present invention, the concentration of sodium hydroxide in the alkaline solution of dimethylglyoxime is 0.1g/L by mass, and the concentration of dimethylglyoxime is in the range of 8 to 12 mmol/L.

In step S2 of the present invention, the preparation process of the bacterial cellulose membrane comprises: preparing a acetobacter xylinum culture medium, inoculating strains under an aseptic condition, activating, standing and culturing the strains at a constant temperature to obtain a film, removing residual bacteria by using a sodium hydroxide solution, and washing the film to be neutral by using deionized water to obtain the transparent hydrogel-shaped bacterial cellulose film.

In some embodiments of the present invention, the medium for Acetobacter xylinum comprises: 2 to 3 wt% of glucose, 0.2 to 0.8 wt% of yeast extract, 0.2 to 0.8 wt% of tryptone, 0.08 to 0.15 wt% of citric acid monohydrate, 0.08 to 0.15 wt% of potassium dihydrogen phosphate, 0.2 to 0.8 wt% of disodium hydrogen phosphate dodecahydrate, and the pH is 5 to 7. The temperature for activating the strain is 28-32 ℃, and the time is 36-72 h; the temperature of the strain constant-temperature static culture is 28-32 ℃, and the time is 7-14 days.

In some more specific embodiments of the invention, the medium for acetobacter xylinum comprises: 2.5 wt% glucose, 0.5 wt% yeast extract, 0.5 wt% tryptone, 0.11 wt% citric acid monohydrate, 0.11 wt% potassium dihydrogen phosphate, 0.5 wt% disodium hydrogen phosphate dodecahydrate, pH 6.

In the invention, the bacterial cellulose membrane (BC) is modified by a copper ion-hydrogen peroxide carboxylation method to obtain a carboxylated bacterial cellulose membrane.

In some embodiments of the present invention, the modifying process is specifically: immersing a bacterial cellulose membrane in a solution containing copper ions and hydrogen peroxide (H)₂O₂) Heating and stirring the mixed solution, and then washing the mixed solution by water until the mixed solution is washedThe washing solution is neutral, and the carboxylated bacterial cellulose membrane is obtained.

In some more specific embodiments of the invention, the copper ion and hydrogen peroxide (H) comprise₂O₂) In the mixed solution of (1), H₂O₂The concentration is 10-30%, and the concentration of copper ions is 0.018-0.025 g/L; the heating and stirring temperature is 60-65 ℃, the heating and stirring time is 5-6 h, and the stirring speed is 200-220 r/min; the cleaning mode of the base material is as follows: and ultrasonically cleaning for 10-20 minutes by using ultrapure water, then changing water, and repeating the cleaning steps until the pH value of the cleaning solution is 7, so that the cleaning is finished.

In step S3, the constant temperature oscillation is carried out at 30-40 ℃ for 1-2 h; the freeze-drying process comprises the following steps: the washed neutral carboxylated bacterial cellulose is pre-frozen in a refrigerator at the temperature of minus 80 to minus 60 ℃ for 1 to 6 hours, and then is freeze-dried in a freeze dryer for 24 to 72 hours. The invention can keep the structural form of the membrane from being damaged by freeze drying, and simultaneously avoid the pollution of the medicine by air impurities.

In the invention, the nickel source selected by the standard nickel ion solution is at least one of nickel chloride, nickel sulfate and nickel nitrate, and preferably nickel chloride.

In the invention, the sample to be detected is liquid, and the concentration range of nickel ions in the sample to be detected is 1-50 mg/L.

In the invention, in the processes of preparing the standard colorimetric card and detecting the sample to be detected, the dropping amounts of the standard nickel ion solution and the sample to be detected are consistent. In some embodiments of the invention, the amount added is 0.2mL each.

The second aspect of the invention provides a device for rapidly detecting nickel ions, which comprises a nickel ion detector and a standard colorimetric card.

Example 1

The embodiment provides a method for preparing a nickel ion detector and a standard colorimetric card, which comprises the following steps:

(1) preparing a color developing solution: adding 0.01g of sodium hydroxide and 1mmol of dimethylglyoxime into 100mL of water for dissolving to prepare a dimethylglyoxime alkaline solution;

(2) preparing a bacterial cellulose membrane: 500mL of a culture medium for Acetobacter xylinum (containing 2.5 wt% of glucose, 0.5 wt% of yeast extract, 0.5 wt% of tryptone, 0.11 wt% of citric acid monohydrate, 0.11 wt% of potassium dihydrogen phosphate, and 0.5 wt% of disodium hydrogen phosphate dodecahydrate) was prepared, the pH of the culture medium was adjusted to 6, 5mL of a bacterial solution (deposit No. ATCC 700178) was inoculated under aseptic conditions, the bacterial solution was activated for 48 hours in a 30 ℃ incubator, the activated bacterial solution was transferred to a 10X 20cm plastic box, and the plastic box was left to stand for 10 days at 30 ℃ to obtain a film by culturing, residual bacteria were removed with a sodium hydroxide solution, and the film was washed to neutrality with deionized water to obtain a transparent hydrogel-like bacterial cellulose film.

(3) Preparation of carboxylated bacterial cellulose membranes: 100mL of 20% H was taken₂O₂Adding 4.02mg of copper chloride, putting the bacterial cellulose membrane prepared in the step (2) into the solution, heating the solution to 65 ℃, rotating at the speed of 200r/min, taking out the solution after reacting for 6 hours, ultrasonically cleaning the solution for 10 minutes by using 100mL of ultrapure water, then changing water, repeating the cleaning step until the pH value of the cleaning solution is 7, and finishing the cleaning to obtain the carboxylated bacterial cellulose membrane.

(4) Preparing a nickel ion detector: and (3) immersing the carboxylated bacterial cellulose membrane obtained in the step (3) into the dimethylglyoxime alkaline solution obtained in the step (1), washing after oscillating at the constant temperature of 30 ℃ for 2 hours, taking out the carboxylated bacterial cellulose membrane washed to be neutral, pre-freezing in a refrigerator at the temperature of-80 ℃ for 2 hours, freeze-drying in a freeze-drying machine for 24 hours, taking out, and cutting the cellulose membrane by 5 x 8mm to obtain the nickel ion detector.

(5) Preparing a standard colorimetric card: a series of concentration gradients at pH 9 were: 0.1, 2, 5, 10, 20 and 50mg/L of standard nickel ion solution, transferring 0.2mL of nickel ion solution with different concentrations, respectively and dropwise adding the nickel ion solution on a nickel ion detector, photographing after 30s, recording the color of the detector, and manufacturing into a standard colorimetric card.

The colorimetric card prepared in this example is shown in fig. 1, and the detection limit of the detector for nickel ions is as low as 1 mg/L. FIG. 2 is an SEM image of a nickel ion detector illustrating the successful loading of developer onto a carboxylated bacterial cellulose membrane.

Example 2

The embodiment provides a method for preparing a nickel ion detector and a standard colorimetric card, which comprises the following steps:

(1) preparing a color developing solution: adding 0.01g of sodium hydroxide and 0.8mmol/L of dimethylglyoxime into 100mL of water for dissolving to prepare a dimethylglyoxime alkaline solution;

(2) preparing a bacterial cellulose membrane: 500mL of a culture medium for Acetobacter xylinum (containing 2.5 wt% of glucose, 0.5 wt% of yeast extract, 0.5 wt% of tryptone, 0.11 wt% of citric acid monohydrate, 0.11 wt% of potassium dihydrogen phosphate, and 0.5 wt% of disodium hydrogen phosphate dodecahydrate) was prepared, the pH of the culture medium was adjusted to 6, 5mL of a bacterial solution (accession number ATCC 700178) was inoculated under aseptic conditions, the bacterial solution was activated for 48 hours in a 30 ℃ incubator, the activated bacterial solution was transferred to a 10X 20cm plastic box, and the plastic box was left to stand for 14 days at 30 ℃ to obtain a film by culturing, residual bacteria were removed with a sodium hydroxide solution, and the film was washed to neutrality with deionized water to obtain a transparent hydrogel-like bacterial cellulose film.

(3) Preparation of carboxylated bacterial cellulose membranes: 100mL of 20% H was taken₂O₂Adding 4.02mg of copper chloride, putting the bacterial cellulose membrane prepared in the step (2) into the solution, heating the solution to 60 ℃, rotating at the speed of 200r/min, taking out the solution after reacting for 6 hours, ultrasonically cleaning the solution for 10 minutes by using 100mL of ultrapure water, then changing water, repeating the cleaning step until the pH value of the cleaning solution is 7, and finishing the cleaning to obtain the carboxylated bacterial cellulose membrane.

(4) Preparing a nickel ion detector: and (3) immersing the carboxylated bacterial cellulose membrane obtained in the step (3) into the dimethylglyoxime alkaline solution obtained in the step (1), washing after oscillating at the constant temperature of 30 ℃ for 2 hours, taking out the carboxylated bacterial cellulose membrane washed to be neutral, pre-freezing in a refrigerator at the temperature of-80 ℃ for 2 hours, freeze-drying in a freeze-drying machine for 24 hours, taking out, and cutting the cellulose membrane by 5 x 8mm to obtain the nickel ion detector.

(5) Preparing a standard colorimetric card: a series of concentration gradients at pH 9 were: 0.1, 2, 5, 10, 20 and 50mg/L of standard nickel ion solution, transferring 0.2mL of nickel ion solution with different concentrations, respectively and dropwise adding the nickel ion solution on a nickel ion detector, photographing after 30s, recording the color of the detector, and manufacturing into a standard colorimetric card.

The standard colorimetric card and detection limit prepared in this example are the same as those in example 1.

Example 3

The embodiment provides a method for preparing a nickel ion detector and a standard colorimetric card, which comprises the following steps:

(1) preparing a color developing solution: adding 0.01g of sodium hydroxide and 1.2mmol of dimethylglyoxime into 100mL of water for dissolving to prepare a dimethylglyoxime alkaline solution;

(2) preparing a bacterial cellulose membrane: 500mL of a culture medium for Acetobacter xylinum (containing 2.5 wt% of glucose, 0.5 wt% of yeast extract, 0.5 wt% of tryptone, 0.11 wt% of citric acid monohydrate, 0.11 wt% of potassium dihydrogen phosphate and 0.5 wt% of disodium hydrogen phosphate dodecahydrate) was prepared, the pH of the culture medium was adjusted to 6, 5mL of a bacterial solution (deposit No. ATCC 700178) was inoculated under aseptic conditions, the bacterial solution was activated for 48 hours in a 30 ℃ incubator, the activated bacterial solution was transferred to a 10X 20cm plastic box, and the plastic box was left to stand for 12 days in a 30 ℃ incubator to obtain a film, residual bacteria were removed with a sodium hydroxide solution, and the film was washed to neutrality with deionized water to obtain a transparent hydrogel-like bacterial cellulose film.

(3) Preparation of carboxylated bacterial cellulose membranes: 100mL of 20% H was taken₂O₂Adding 4.02mg of copper chloride, putting the bacterial cellulose membrane prepared in the step (2) into the solution, heating the solution to 60 ℃, rotating at the speed of 200r/min, taking out the solution after reacting for 6 hours, ultrasonically cleaning the solution for 10 minutes by using 100mL of ultrapure water, then changing water, repeating the cleaning step until the pH value of the cleaning solution is 7, and finishing the cleaning to obtain the carboxylated bacterial cellulose membrane.

(4) Preparing a nickel ion detector: and (3) immersing the carboxylated bacterial cellulose membrane obtained in the step (3) into the dimethylglyoxime alkaline solution obtained in the step (1), washing after oscillating at the constant temperature of 30 ℃ for 2 hours, taking out the carboxylated bacterial cellulose membrane washed to be neutral, pre-freezing in a refrigerator at the temperature of-80 ℃ for 2 hours, freeze-drying in a freeze-drying machine for 24 hours, taking out, and cutting the cellulose membrane by 5 x 8mm to obtain the nickel ion detector.

(5) Preparing a standard colorimetric card: a series of concentration gradients at pH 9 were: 0.1, 2, 5, 10, 20 and 50mg/L of standard nickel ion solution, transferring 0.2mL of nickel ion solution with different concentrations, respectively and dropwise adding the nickel ion solution on a nickel ion detector, photographing after 30s, recording the color of the detector, and manufacturing into a standard colorimetric card.

The standard colorimetric card and detection limit prepared in this example are the same as those in example 1.

Example 4

A method for rapid detection of nickel ions, comprising the steps of:

(1) preparing a nickel ion solution: preparing a nickel ion solution with the concentration of 1mg/L by using 100mg/L of nickel ion mother liquor; the nickel source in the nickel ion mother liquor is nickel chloride.

(2) Detecting nickel ions: 0.2mL of the prepared nickel ion solution is dripped on a nickel ion detector, the color of the nickel ion solution is compared with a standard color comparison card, and the concentration of the nickel ions is read out to be 1 mg/L; in this example, nickel ions were detected using the nickel ion detector and the standard color chart prepared in example 1.

Example 5

A method for rapid detection of nickel ions, comprising the steps of:

(1) preparing a nickel ion solution: preparing a nickel ion solution with the concentration of 2mg/L by using 100mg/L of nickel ion mother liquor; the nickel source in the nickel ion mother liquor is nickel chloride.

(2) Detecting nickel ions: 0.2mL of the prepared nickel ion solution is dripped on a nickel ion detector, the color of the nickel ion solution is compared with a standard color comparison card, and the concentration of the nickel ions is read out to be 2 mg/L; in this example, nickel ions were detected using the nickel ion detector and the standard color chart prepared in example 1.

Example 6

A method for rapid detection of nickel ions, comprising the steps of:

(1) preparing a nickel ion solution: preparing a nickel ion solution with the concentration of 5mg/L by using 100mg/L of nickel ion mother liquor; the nickel source in the nickel ion mother liquor is nickel chloride.

(2) Detecting nickel ions: 0.2mL of the prepared nickel ion solution is dripped on a nickel ion detector, the color of the nickel ion solution is compared with a standard color comparison card, and the concentration of the nickel ions is read out to be 5 mg/L; in this example, nickel ions were detected using the nickel ion detector and the standard color chart prepared in example 1.

Example 7

A method for rapid detection of nickel ions, comprising the steps of:

(1) preparing a nickel ion solution: preparing a nickel ion solution with the concentration of 10mg/L by using 100mg/L of nickel ion mother liquor; the nickel source in the nickel ion mother liquor is nickel chloride.

(2) Detection of nickel ions: 0.2mL of the prepared nickel ion solution is dripped on a nickel ion detector, the color of the nickel ion solution is compared with a standard color comparison card, and the concentration of the nickel ions is read out to be 10 mg/L; in this example, nickel ions were detected using the nickel ion detector and the standard color chart prepared in example 1.

Example 8

A method for rapid detection of nickel ions, comprising the steps of:

(1) preparing a nickel ion solution: preparing a nickel ion solution with the concentration of 20mg/L by using 100mg/L of nickel ion mother liquor; the nickel source in the nickel ion mother liquor is nickel chloride.

(2) Detecting nickel ions: 0.2mL of the prepared nickel ion solution is dripped on a nickel ion detector, the color of the nickel ion solution is compared with a standard color comparison card, and the concentration of the nickel ions is read out to be 20 mg/L; in this example, nickel ions were detected using the nickel ion detector and the standard color chart prepared in example 1.

Example 9

A method for rapid detection of nickel ions, comprising the steps of:

(1) preparing a nickel ion solution: preparing a nickel ion solution with the concentration of 50mg/L by using 100mg/L of nickel ion mother liquor; the nickel source in the nickel ion mother liquor is nickel chloride.

(2) Detecting nickel ions: 0.2mL of the prepared nickel ion solution is dripped on a nickel ion detector, the color of the nickel ion solution is compared with a standard color comparison card, and the concentration of the nickel ions is read out to be 50 mg/L; in this example, nickel ions were detected using the nickel ion detector and the standard color chart prepared in example 1.

Example 10

The optimum pH research of nickel ions comprises the following steps:

preparing 10mg/L of nickel ion standard solution, and adjusting the pH of the solution to be: 1. 3, 5, 7, 9, 11, 13; 1mL of nickel ion solution with different pH and 1mL of the alkaline solution of dimethylglyoxime prepared in example 1 were added, and the absorbance of the solution at the peak of 547nm was measured, and the results are shown in FIG. 3. As can be seen from fig. 3, the optimum pH of the nickel ions is 9.

Example 11

The method for researching the optimal color developing agent concentration of the nickel ions comprises the following steps:

preparing a nickel ion standard solution with the concentration of 50mg/L, pH-9, and preparing a color developing agent solution with the concentration of 2-14 mmol/L (the mass concentration of sodium hydroxide is 0.1 g/L); 1mL of nickel ion standard solution and 1mL of dimethylglyoxime alkaline solution with different concentrations are added, and the absorbance of the solution at the peak 547 is measured, and the result is shown in FIG. 4. As can be seen from FIG. 4, the optimum concentration of the developer is 8 mmol/L.

Example 12

The selectivity exploration of the solution of nickel ions comprises the following steps:

a series of 16 common heavy metal ions of 5mg/L are prepared, 1mL of common metal solution and 1mL of dimethylglyoxime alkaline solution are added into a 10mL glass bottle, the absorbance of the solution at the wavelength of 547nm is measured, and the absorbance is recorded and finished as shown in figure 5. As can be seen from fig. 5, the method has good selectivity for nickel ions.

Comparative example 1

The only difference compared to example 1 is that the bacterial cellulose membrane was used directly to prepare a nickel ion detector, a standard colorimetric card. The method comprises the following specific steps:

(3) preparing a nickel ion detector: and (2) immersing the bacterial cellulose membrane into the dimethylglyoxime alkaline solution obtained in the step (1), washing after oscillating at the constant temperature of 30 ℃ for 2 hours, taking out the bacterial cellulose membrane washed to be neutral, pre-freezing in a refrigerator at the temperature of-80 ℃ for 2 hours, freeze-drying in a freeze dryer for 24 hours, taking out and cutting the bacterial cellulose membrane into 5 x 8mm to obtain the bacterial cellulose nickel ion detector.

The rest of the procedure was identical to example 1.

The results show that: the detection limit of the bacterial cellulose on the nickel ions is 2mg/L, which shows that the detection capability of the bacterial cellulose on the nickel ions is improved through carboxylation.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention.