CN110695370B - Copper-based nano composite material and preparation method and application thereof - Google Patents

Abstract

The invention belongs to the field of food detection and nano material synthesis, and particularly discloses a copper-based nano composite material and a preparation method and detection application thereof. The copper-based nano composite material takes a waste egg membrane as a template; and then reducing the copper salt into copper nano particles by taking the plant extract as a reducing agent, thereby obtaining the copper nano particles. The copper-based nanocomposite material has high efficiency and sensitivity on nitrite detection, strong anti-interference capability and wide application prospect. The preparation material is easy to obtain, the requirements on the preparation process and equipment are simple, the material has no pollution to the environment, and the cost is low.

Description

A kind of copper-based nanocomposite material and its preparation method and application

technical field

The invention belongs to the technical field of food detection and nanometer materials, and more specifically relates to a copper-based nanocomposite material, a preparation method thereof and an electrochemical detection application of nitrous acid.

Background technique

Nitrite is a dangerous potentially inorganic pollutant widely present in the environment, food, industry and physiological systems. Under the acidic conditions in the stomach, when nitrite combines with secondary and tertiary amines present in food, it is easily transformed into carcinogenic N-nitrosoamines, leading to gastric cancer. Importantly, nitrite ions are considered to be one of the main harmful pollutants in nuclear power plant wastewater production. It causes corrosive behavior when dissolved in water and acts as an environmentally harmful substance for the degradation of some essential fertilizers. In addition, nitrite is often used as a food additive because it can effectively prevent microorganisms from causing food poisoning. Therefore, it is necessary to detect and monitor the concentration level of nitrite in the environment and physiological system. Therefore, the development of sophisticated analytical techniques to study the determination of nitrite ions in recent years is of critical importance to the environment and human health.

The problem of nitrite has attracted people's great attention, and there are many methods that can be used to detect nitrite. Usually, the methods for determining nitrite include spectrophotometry, gas chromatography, high performance liquid chromatography, chemical reagent method, capillary electrophoresis and electrochemical method. Among them, the electrochemical method has many advantages, the reason is that the manufacture is simple, the reaction is rapid, the sensitivity is high, and the cost is low. Therefore, electrochemical methods have recently attracted much attention for the development of high-performance nitrite sensors.

Compared with various noble metal (Au, Ag, Pd, and Pt) nanoparticles, the selection of copper nanoparticles was inspired and valued for numerous applications due to their low cost, high catalytic, optical, conductive, and antibacterial properties. Furthermore, it is of greater importance to produce nanomaterials without harming the environment or human health in order to provide sustainable solutions to environment-related problems.

Natural biological materials have many fine hierarchical structures that cannot be imitated by artificial techniques. These exotic geometries and surface topography make biomaterials ideal templates for the synthesis of different nanomaterials with uniform size and complex structure. Eggshell membrane is an environmental waste with uniform microporous structure and interwoven fiber network, which is a good template for constructing three-dimensional nanostructures. Making full use of discarded eggshell membranes as biological templates to construct high value-added nanomaterials meets the needs of current green development.

In summary, the present invention utilizes the special fiber network structure of eggshell membranes to synthesize copper nanoparticles in situ. This unique three-dimensional structure can provide more adsorption sites and larger specific surface area for electrochemical reactions. Furthermore, unlike nanoparticles, which are usually inactivated by aggregation, porous networks have a rigid structure that makes them immune to inactivation by aggregation. These excellent properties make it an efficient and durable electrocatalytic interface material for catalytic oxidation of nitrite. Based on this, we developed an electrochemical nitrite sensor with high sensitivity and selectivity.

Contents of the invention

The invention provides a copper-based nanocomposite material aiming at the shortcomings of the existing nitrite detection technology.

Another object of the present invention is to provide a method for preparing the above-mentioned copper-based nanocomposite material. The material is easy to obtain, the preparation process and equipment requirements are simple, and the material has no pollution to the environment and is low in cost.

Another object of the present invention is to provide the application of the above-mentioned copper-based nanocomposite material.

The purpose of the present invention is achieved through the following technical solutions:

A copper-based nano-composite material for nitrite detection, the copper-based nano-composite material is prepared by using eggshell membrane as a carrier, and using plant matter as a reducing agent to reduce copper salt solution to copper nanoparticles in situ.

Preferably, the copper-based nanocomposite material uses eggshell membrane as a template.

Preferably, the eggshell membrane includes any one of eggshell membranes, duck eggshell membranes and goose eggshell membranes.

Preferably, the concentration of the copper salt solution is 0.01-0.1 M, preferably 0.05 M.

Preferably, the concentration of the plant substance reducing agent extract is 0.1-1 g/mL, and the plant substance extract is the rhizome and leaf extract of camphor, arborvitae, eucalyptus, green tea, peppermint or lemon.

The preparation method of described copper-based nanocomposite material comprises the following specific steps:

(1) Eggshell membrane pretreatment: collect discarded eggshells, wash the collected eggshells repeatedly with clean water, soak in clean water at room temperature for 1 to 5 hours, and use tweezers to separate the eggshell membranes from the soaked eggshells. Tear off, wash and set aside;

(2) Preparation of eggshell membrane carrier: take the eggshell membrane in step (1), immerse it in hydrochloric acid solution, soak for 12-24 hours, take it out and dry it, grind it with a grinder to obtain the eggshell membrane carrier;

(3) Adsorption of copper ions: immerse the eggshell membrane carrier obtained in step (2) into a copper salt solution, soak at room temperature for 12-24 hours, and adsorb copper ions to the eggshell membrane carrier;

(4) In situ reduction of copper nanoparticles: the eggshell membrane carrier with adsorbed copper ions obtained in step (3) was soaked in the plant extract solution at room temperature, and the copper ions were reduced to copper nanoparticles in situ, and then Filtering the eggshell membrane loaded with copper nanoparticles and drying;

(5) Preparation of composite copper nanomaterials supported by eggshell membrane: the eggshell membrane loaded with copper nanoparticles dried in step (4) was placed in a muffle furnace for calcination at 100-300 °C for 2-5 h to obtain copper A copper-based nanocomposite material with a loading mass percentage of nanoparticles of 0.1% to 3.0%.

Preferably, the soaking time in step (4) is 24-48 h.

The application of the copper-based nanocomposite material in the detection of nitrite in food.

Compared with the prior art, the present invention has the following beneficial effects:

1. The copper-based nanocomposite material of the present invention uses discarded eggshell membranes as a carrier, has a wide source of raw materials and low cost, not only does not produce any pollution, but also realizes the recycling and reuse of biological waste;

2. The copper-based nanomaterial prepared by the present invention has a copper loading weight percentage of 0.1-3.0%, and the lowest detectable nitrite is 0.63 μM, showing good detectability.

3. The preparation materials of the present invention are easy to obtain, the preparation process and equipment requirements are simple, and the reaction conditions are mild.

Description of drawings

Fig. 1 is the physical figure of the copper-based powdered nanocomposite material prepared by the embodiment of the present invention 5;

Fig. 2 is the scanning electron micrograph of the copper-based nanocomposite material prepared in Example 5 of the present invention;

Fig. 3 is a cyclic voltammetry curve for detecting nitrite by the copper-based nanocomposite prepared in Example 5 of the present invention.

detailed description

The content of the present invention will be further described below in conjunction with specific examples, but it should not be construed as a limitation of the present invention. Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art. Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in the technical field.

Example 1

A copper-based nanocomposite material for nitrite detection is prepared by using eggshell membrane as a carrier, and then reducing copper salt solution to copper nanoparticles in situ with a reducing agent.

A method for preparing a copper-based nanocomposite material for nitrite detection, comprising the following steps:

(1) Eggshell membrane pretreatment: collect discarded eggshells; wash the collected eggshells repeatedly with clean water, and soak them in clean water for 1 hour at room temperature; use tweezers to tear off the egg membranes from the soaked eggshells, cleaning spare;

(2) Preparation of eggshell membrane carrier: take the eggshell membrane in step (1), immerse it in hydrochloric acid solution, soak for 12 hours, take it out and dry it, grind it as small as possible with a grinder, and obtain the eggshell membrane carrier;

(3) Adsorption of copper ions: immerse 1 g of the eggshell membrane carrier obtained in step (2) into 50 mL of 0.01 M copper chloride solution for 20 h at room temperature to adsorb copper ions onto the eggshell membrane carrier;

(4) In situ reduction of copper nanoparticles: Soak the eggshell membrane carrier with adsorbed copper ions obtained in step (3) in 25 mL of 0.1 g/mL cinnamon extract at room temperature, and in situ reduce the copper ions Reduce to copper nanoparticles, then filter and dry the eggshell membrane loaded with copper nanoparticles;

(5) Preparation of composite copper nanomaterials supported by eggshell membrane: the eggshell membrane loaded with copper nanoparticles dried in step (4) was calcined in a muffle furnace at 100 °C for 2 h to obtain the mass of copper nanoparticles loaded The percentage is 0.1% composite copper nanomaterials.

The copper-based nanomaterial prepared by the above method is applied to the detection of nitrite.

The copper-based nanomaterial is used for the method for nitrite, comprises the steps:

1. Take 6 mg of the prepared copper-based nanocomposite, add 3 mL of deionized water, and sonicate in an ultrasonic machine for 1 hour to obtain a mixed solution;

2. Take 5 μL of the mixed solution and drop it on the surface of the electrode, dry it at room temperature, and store the electrode in a refrigerator at 4 °C for later use;

3. Prepare 10 mL, 0.5 mM nitrite solution, and measure its cyclic voltammetry curve in the electrochemical workstation.

Example 2

A copper-based nanomaterial used for nitrite detection is prepared by using eggshell membrane as a carrier; and then using a reducing agent to reduce copper salt solution in situ to copper nanoparticles.

A method for preparing copper-based nanomaterials for nitrite detection, comprising the following steps:

(1) Eggshell membrane pretreatment: collect discarded duck eggshells; wash the collected eggshells repeatedly with clean water, soak them in clean water at room temperature for 2 hours; use tweezers to tear off the duck eggshells from the soaked duck eggshells , wash and reserve;

(2) Preparation of eggshell membrane carrier: take the eggshell membrane in step (1), immerse it in hydrochloric acid solution, soak for 14 hours, take it out and dry it, grind it as small as possible with a grinder, and obtain the eggshell membrane carrier;

(3) Adsorption of copper ions: immerse 1 g of the eggshell membrane carrier obtained in step (2) into 50 mL of 0.02 M copper nitrate solution, soak at room temperature for 22 h, and adsorb copper ions to the eggshell membrane carrier;

(4) In situ reduction of copper nanoparticles: Soak the eggshell membrane carrier with adsorbed copper ions obtained in step (3) in 25 mL of 0.1 g/mL extract of Thuja arborvitae at room temperature to in situ reduce the copper ions Reduce to copper nanoparticles, then filter and dry the eggshell membrane loaded with copper nanoparticles;

(5) Preparation of composite copper nanomaterials supported by eggshell membrane: the eggshell membrane loaded with copper nanoparticles dried in step (4) was calcined in a muffle furnace at 200 °C for 2 h to obtain the mass of copper nanoparticles loaded Composite copper nanomaterials with a percentage of 1%.

The copper-based nanomaterial prepared by the above method is applied to the detection of nitrite.

The copper-based nanomaterial is used for the method for nitrite, comprises the steps:

1. Take 4 mg of the prepared copper-based nanomaterials, add 2 mL of deionized water, and sonicate in an ultrasonic machine for 2 hours to obtain a mixed solution;

2. Take 10 μL of the mixed solution and drop it on the surface of the electrode, dry it at room temperature, and store the electrode in a refrigerator at 4 °C for later use;

3. Prepare 10 mL, 0.6 mM nitrite solution, and measure its cyclic voltammetry curve in the electrochemical workstation.

Example 3

A copper-based nanomaterial used for nitrite detection is prepared by using eggshell membrane as a carrier; and then using a reducing agent to reduce copper salt solution in situ to copper nanoparticles.

A method for preparing copper-based nanomaterials for nitrite detection, comprising the following steps:

(1) Eggshell membrane pretreatment: collect discarded goose eggshells; wash the collected goose eggshells repeatedly with clean water, and soak them in clean water for 3 hours at room temperature; Tear off, wash and set aside;

(2) Preparation of eggshell membrane carrier: take the eggshell membrane in step (1), immerse it in hydrochloric acid solution, soak for 15 hours, take it out and dry it, grind it as small as possible with a grinder, and obtain the eggshell membrane carrier;

(3) Adsorption of copper ions: immerse 1 g of the eggshell membrane carrier obtained in step (2) into 50 mL of 0.02M copper sulfate solution, soak at room temperature for 24 h, and absorb copper ions onto the eggshell membrane carrier;

(4) In situ reduction of copper nanoparticles: Soak the eggshell membrane carrier with adsorbed copper ions obtained in step (3) in 40 mL of 0.5 g/mL green tea extract at room temperature to reduce the copper ions in situ For copper nanoparticles, then the eggshell membrane loaded with copper nanoparticles is filtered and dried;

(5) Preparation of composite copper nanomaterials supported by eggshell membranes: the eggshell membranes loaded with copper nanoparticles dried in step (4) were calcined in a muffle furnace at 300 °C for 2 h to obtain the mass of copper nanoparticles loaded Composite copper nanomaterials with a percentage of 2%.

The copper-based nanomaterial prepared by the above method is applied to the detection of nitrite.

The copper-based nanomaterial is used for the method for nitrite, comprises the steps:

1. Take 8 mg of the prepared copper-based nanomaterials, add 4 mL of deionized water, and sonicate in an ultrasonic machine for 3 hours to obtain a mixed solution;

2. Take 15 μL of the mixed solution and drop it on the surface of the electrode, dry it at room temperature, and store the electrode in a refrigerator at 4 °C for later use;

3. Prepare 10 mL, 0.4 mM nitrite solution, and measure its cyclic voltammetry curve in the electrochemical workstation.

Example 4

A copper-based nanomaterial used for nitrite detection is prepared by using eggshell membrane as a carrier; and then using a reducing agent to reduce copper chloride solution in situ to copper nanoparticles.

A method for preparing copper-based nanomaterials for nitrite detection, comprising the following steps:

(1) Eggshell membrane pretreatment: collect discarded eggshells; wash the collected eggshells repeatedly with clean water, and soak them in clean water for 4 hours at room temperature; use tweezers to tear off the egg membranes from the soaked eggshells, cleaning spare;

(2) Preparation of eggshell membrane carrier: take the eggshell membrane in step (1), immerse it in hydrochloric acid solution, soak for 16 hours, take it out and dry it, grind it as small as possible with a grinder, and obtain the eggshell membrane carrier;

(3) Adsorption of copper ions: immerse 1 g of the eggshell membrane carrier obtained in step (2) into 50 mL of 0.02 M copper chloride solution, and soak for 18 h at room temperature to adsorb copper ions to the eggshell membrane carrier;

(4) In situ reduction of copper nanoparticles: Soak the eggshell membrane carrier with adsorbed copper ions obtained in step (3) in 35 mL of 0.1 g/mL peppermint extract at room temperature to reduce the copper ions in situ For copper nanoparticles, then the eggshell membrane loaded with copper nanoparticles is filtered and dried;

(5) Preparation of composite copper nanomaterials supported by eggshell membranes: the eggshell membranes loaded with copper nanoparticles dried in step (4) were calcined in a muffle furnace at 200 °C for 3 h to obtain the mass of copper nanoparticles loaded The percentage is 1.4% composite copper nanomaterials.

The copper-based nanomaterial prepared by the above method is applied to the detection of nitrite.

The copper-based nanomaterial is used for the method for nitrite, comprises the steps:

1. Take 3 mg of the prepared copper-based nanomaterials, add 1 mL of deionized water, and sonicate in an ultrasonic machine for 4 hours to obtain a mixed solution;

2. Take 5 μL of the mixed solution and drop it on the surface of the electrode, dry it at room temperature, and store the electrode in a refrigerator at 4 °C for later use;

3. Prepare 10 mL, 0.3 mM nitrite solution, and measure its cyclic voltammetry curve in the electrochemical workstation.

Example 5

A copper-based nanomaterial used for nitrite detection is prepared by using eggshell membrane as a carrier; and then using a reducing agent to reduce copper salt solution in situ to copper nanoparticles.

A method for preparing copper-based nanomaterials for nitrite detection, comprising the following steps:

(1) Eggshell membrane pretreatment: collect discarded eggshells; wash the collected eggshells repeatedly with clean water, and soak them in clean water for 5 hours at room temperature; use tweezers to tear off the duck egg membranes from the soaked duck eggshells, cleaning spare;

(2) Preparation of eggshell membrane carrier: take the eggshell membrane in step (1), immerse it in hydrochloric acid solution, soak it for 24 hours, take it out and dry it, grind it as small as possible with a grinder, and obtain the eggshell membrane carrier;

(3) Adsorption of copper ions: immerse 1 g of the eggshell membrane carrier obtained in step (2) into 50 mL of 0.05M copper nitrate solution, soak at room temperature for 24 h, and adsorb copper ions on the eggshell membrane carrier;

(4) In situ reduction of copper nanoparticles: Soak the eggshell membrane carrier with adsorbed copper ions obtained in step (3) in 50 mL of 0.3 g/mL eucalyptus leaf extract at room temperature to in situ reduce the copper ions Reduce to copper nanoparticles, then filter and dry the eggshell membrane loaded with copper nanoparticles;

(5) Preparation of composite copper nanomaterials supported by eggshell membrane: the eggshell membrane loaded with copper nanoparticles dried in step (4) was calcined in a muffle furnace at 300 °C for 5 h to obtain the mass of copper nanoparticles loaded Composite copper nanomaterials with a percentage of 3%.

The copper-based nanomaterial prepared by the above method is applied to the detection of nitrite.

The copper-based nanomaterial is used for the method for nitrite, comprises the steps:

1. Take 10 mg of the prepared copper-based nanomaterials, add 5 mL of deionized water, and sonicate in an ultrasonic machine for 5 hours to obtain a mixed solution;

2. Take 10 μL of the mixed solution and drop it on the surface of the electrode, dry it at room temperature, and store the electrode in a refrigerator at 4 °C for later use;

3. Prepare 10 mL of 0.7 mM nitrite solution, and measure its cyclic voltammetry curve in the electrochemical workstation.

Figure 2 is a scanning electron microscope image of the copper-based nanocomposite of the present invention; from the figure we can see that a large amount of copper-based nanocomposites are loaded on the surface of the eggshell membrane.

Fig. 3 is the cyclic voltammetry graph of detecting nitrite by the copper-based nanocomposite material of the present invention; from the figure we can see the obvious nitrite oxidation peak, indicating that the material can be used for the detection of nitrite.

The above-mentioned embodiment is a preferred embodiment of the present invention, but the embodiment of the present invention is not limited by the above-mentioned embodiment, and any other changes, modifications, substitutions, combinations and modifications made without departing from the spirit and principles of the present invention Simplifications should be equivalent replacement methods, and all are included in the protection scope of the present invention.

Claims (1)

1. The application of the copper-based nano composite material is characterized in that: the copper-based nano composite material is applied to detection of nitrite in food;

the copper-based nano composite material is prepared by taking an eggshell membrane as a carrier and then reducing a copper salt solution into copper nano particles in situ by taking a vegetable matter extracting solution as a reducing agent;

the copper-based nano composite material takes an eggshell membrane as a template; the eggshell membrane comprises any one of egg membrane, duck egg membrane and goose egg membrane; the concentration of the copper salt solution is 0.01-0.1M; the vegetable matter extracting solution is an extracting solution of cinnamomum camphora, platycladus orientalis, eucalyptus, green tea, mint or lemon, and the concentration of the vegetable matter extracting solution is 0.1-1 g/mL;

the method comprises the following specific steps:

(1) Egg shell membrane pretreatment: collecting waste egg shells, repeatedly washing the collected egg shells with clear water, soaking the collected egg shells in the clear water for 1-5 hours at room temperature, tearing off egg shell membranes from the soaked egg shells with tweezers, and washing the egg shells for later use;

(2) Preparing an eggshell membrane carrier: taking the eggshell membrane obtained in the step (1), soaking the eggshell membrane in a hydrochloric acid solution for 12-24 hours, taking out the eggshell membrane, drying the eggshell membrane, and grinding the eggshell membrane by using a grinder to obtain an eggshell membrane carrier;

(3) Copper ion adsorption: immersing the eggshell membrane carrier obtained in the step (2) into a copper salt solution, and immersing at room temperature for 12-24 h to absorb copper ions onto the eggshell membrane carrier;

(4) In-situ reduction of copper nanoparticles: soaking the eggshell membrane carrier adsorbed with the copper ions obtained in the step (3) in a plant extract at room temperature, reducing the copper ions into copper nanoparticles in situ, filtering the eggshell membrane loaded with the copper nanoparticles, and drying;

(5) Preparing the composite copper nano material loaded by the eggshell membrane: placing the eggshell membrane loaded with the copper nanoparticles dried in the step (4) in a muffle furnace to calcine at 100-300 ℃ for 2-5 h, and obtaining the copper-based nanocomposite material with the copper nanoparticles loaded with the mass percent of 0.1-3.0%;

the soaking time in the step (4) is 12 to 48 hours.

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