阅读说明：本技术 一种太阳光敏感型除草剂纳米囊及其制备方法和应用 (Sunlight sensitive type herbicide nanocapsule and preparation method and application thereof ) 是由 王瑞兵 高成 李铭源 许贝文 于 2018-06-29 设计创作，主要内容包括：一种太阳光敏感型除草剂纳米囊及其制备方法和应用,涉及超分子药物载体技术领域。太阳光敏感型除草剂纳米囊主要是由葫芦脲、甲基紫晶、4-己基偶氮苯自组装形成的纳米囊负载除草剂形成的,除草剂纳米囊能够响应太阳光照刺激而释放出被包裹的除草剂,该太阳光响应型除草剂纳米囊为新型“绿色除草剂”,对使用者安全无害、对环境友好,且具有较好的除草效果；该太阳光敏感型除草剂纳米囊的制备方法是将葫芦脲、甲基紫晶和除草剂溶解于水中；滴加4-己基偶氮苯的有机溶剂溶液,并搅拌；在水中透析除去有机溶剂,该工艺简单。太阳光敏感型除草剂纳米囊的应用,将除草剂纳米囊的水溶液喷洒于植物表面,并经太阳光照射,可达到除草效果。(A sunlight sensitive herbicide nanocapsule and a preparation method and application thereof relate to the technical field of supramolecular drug carriers. The sunlight-sensitive herbicide nanocapsule is mainly formed by self-assembling cucurbituril, methyl amethyst and 4-hexyl azobenzene to form a nanocapsule-loaded herbicide, the herbicide nanocapsule can respond to sunlight stimulation to release the coated herbicide, and the sunlight-responsive herbicide nanocapsule is a novel 'green herbicide', is safe and harmless to users, is environment-friendly and has a good weeding effect; the preparation method of the sunlight sensitive herbicide nanocapsule comprises the steps of dissolving cucurbituril, methyl amethyst and a herbicide in water; dropwise adding an organic solvent solution of 4-hexylazobenzene, and stirring; the organic solvent is removed by dialysis in water, and the process is simple. The application of the sunlight-sensitive type herbicide nanocapsule is that the water solution of the herbicide nanocapsule is sprayed on the surface of a plant and is irradiated by sunlight to achieve the weeding effect.)

1. A sunlight-sensitive herbicide nanocapsule, comprising:

the nanocapsule is formed by self-assembling cucurbituril, methyl amethyst and 4-hexyl azobenzene; and

a herbicide loaded in the nanocapsule.

2. The sunlight-sensitive herbicide nanocapsule of claim 1, wherein the cucurbituril is selected from cucurbituril [8-10], in particular cucurbituril [8 ].

3. The sunlight-sensitive herbicide nanocapsule of claim 1, wherein the molar ratio of the cucurbituril to the methyl violet crystal to the 4-hexylazobenzene is 1-2: 1-2: 1 to 2.

4. The sunlight-sensitive herbicide nanocapsule of claim 1, wherein the herbicide is selected from any one of paraquat, diquat, alachlor, acetochlor, glufosinate and glyphosate.

5. The sunlight-sensitive herbicide nanocapsule of claim 1 wherein the concentration of the herbicide by weight in the herbicide nanocapsule is greater than 0 and less than or equal to 5%.

6. A method of preparing the sunlight-sensitive herbicide nanocapsule of any one of claims 1 to 5, comprising the steps of:

dissolving cucurbituril, methyl amethyst and herbicide in water;

adding an organic solvent solution of 4-hexylazobenzene, stirring to form a photosensitive amphiphilic compound, and simultaneously realizing the loading of the herbicide in the process of self-assembly to form a nano capsule;

the organic solvent was removed by dialysis in water.

7. The method of preparing the sunlight-sensitive herbicide nanocapsule of claim 6, wherein the organic solvent is at least one selected from the group consisting of ethanol, acetone, N-dimethylformamide, and dimethylsulfoxide.

8. The method for preparing the sunlight-sensitive herbicide nanocapsule of claim 6, wherein the stirring time is not less than 0.5 hours.

9. The method for preparing the sunlight-sensitive herbicide nanocapsule of claim 6, wherein the dialyzed solution is filtered through a microporous membrane with a pore size of 0.4-0.5 μm and then lyophilized to form a powdered product.

10. Use of the sunlight-sensitive herbicide nanocapsule of any one of claims 1 to 5, wherein the herbicide nanocapsule is applied to a plant surface and irradiated with sunlight.

Technical Field

The invention relates to the technical field of supramolecular drug carriers, and particularly relates to a sunlight sensitive herbicide nanocapsule as well as a preparation method and application thereof.

Background

Since the invention of herbicide, which has played an important role in the development of agriculture, the herbicide greatly improves the yield of crops, and its effect is still irreplaceable today. With the widespread use of herbicides worldwide, the problems caused by the use of large amounts of highly toxic herbicides are constantly exposed while bringing economic benefits to us: firstly, the environmental pollution of the herbicide is more and more serious; secondly, the attention of consumers to the toxicity and the residual herbicide of the herbicide is higher and higher. In addition, the poisoning of herbicide users occurs frequently, most patients can be basically cured after rescue, but sequela or no medicine can be saved. For example, paraquat is the herbicide with the highest mortality rate in human acute poisoning, has low half lethal dose, and is not soluble in drugs. Therefore, the development of new herbicide components or new formulations with high efficiency, low toxicity, broad spectrum, low dosage and little environmental pollution is becoming the mainstream.

At present, most herbicide production enterprises consider how to quickly weed, reduce cost and pursue simple production process, and at least more than half of the commercially sold herbicides are high-toxicity herbicides. In order to reduce the harm of the high-toxicity herbicide to users, the existing high-toxicity herbicide is only used by simply adding a smelling agent, a vomit agent or a color indicator for reminding of taking the herbicide by mistake or changing a water aqua into a powder agent for being prepared at present, but the measures cannot fundamentally solve the toxicity problem of the high-toxicity herbicide.

Therefore, there is a need to develop a true "green herbicide", i.e., a herbicide that is safe and harmless to human health and environmentally friendly.

Disclosure of Invention

The invention aims to provide a sunlight response type herbicide nanocapsule which is a novel green herbicide, is safe and harmless to users, is environment-friendly and has a good weeding effect.

The invention also aims to provide a preparation method of the solar photosensitive herbicide nanocapsule, which is simple in process.

The invention also aims to provide the application of the solar-sensitive herbicide nanocapsule, wherein the aqueous solution of the herbicide nanocapsule is sprayed on the surface of a plant and is irradiated by sunlight to achieve the weeding effect.

The technical problem to be solved by the invention is realized by adopting the following technical scheme.

The invention provides a sunlight sensitive herbicide nanocapsule, which comprises:

the nanocapsule is formed by self-assembling cucurbituril, methyl amethyst and 4-hexyl azobenzene; and

and the herbicide is loaded in the nanocapsule.

Further, in a preferred embodiment of the invention, the cucurbiturils are selected from cucurbiturils [8-10], in particular cucurbiturils [8 ].

Further, in a preferred embodiment of the invention, the molar ratio of cucurbituril, methyl violet and 4-hexylazobenzene is 1-2: 1-2: 1 to 2.

Further, in a preferred embodiment of the present invention, the herbicide is selected from any one of paraquat, diquat, alachlor, acetochlor, glufosinate and glyphosate.

Further, in a preferred embodiment of the invention, the weight concentration of the herbicide in the herbicide nanocapsule is greater than 0 and less than or equal to 5%.

The invention provides a preparation method of the solar photosensitive herbicide nanocapsule, which comprises the following steps:

dissolving cucurbituril, methyl amethyst and herbicide in water;

adding an organic solvent solution of 4-hexylazobenzene, stirring to form a photosensitive amphiphilic compound, and realizing the loading of the herbicide in the process of self-assembly to form the nanocapsule;

the organic solvent was removed by dialysis in water.

Further, in a preferred embodiment of the present invention, the organic solvent is at least one selected from the group consisting of ethanol, acetone, N-dimethylformamide and dimethylsulfoxide.

Further, in the preferred embodiment of the present invention, the stirring time is 0.5 hours or more.

Further, in the preferred embodiment of the present invention, the dialyzed solution is filtered through a microporous membrane with a pore size of 0.4 to 0.5 μm, and then lyophilized to form a powder product.

The invention provides an application of the solar photosensitive herbicide nanocapsule, which is characterized in that the herbicide nanocapsule is applied to the surface of a plant and is irradiated by sunlight.

The solar photosensitive herbicide nanocapsule of the embodiment of the invention, the preparation method and the application thereof have the beneficial effects that: the solar light-sensitive herbicide nanocapsule provided by the embodiment of the invention is mainly formed by self-assembling cucurbituril, methyl amethyst and 4-hexylazobenzene to form a nanocapsule-loaded herbicide, the herbicide nanocapsule can respond to solar illumination stimulation to release the wrapped herbicide sunlight-responsive herbicide nanocapsule to be a novel 'green herbicide', is safe and harmless to a user, is environment-friendly, and has a good weeding effect; the preparation method of the sunlight sensitive herbicide nanocapsule comprises the steps of dissolving cucurbituril, methyl amethyst and a herbicide in water; dropwise adding an organic solvent solution of 4-hexylazobenzene, and stirring; the organic solvent is removed by dialysis in water, and the process is simple. The application of the solar photosensitive type herbicide nanocapsule provided by the embodiment of the invention can achieve a weeding effect by spraying the water solution of the herbicide nanocapsule on the surface of a plant and irradiating the plant by sunlight.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIG. 1 is a transmission electron microscope photograph of a solar-sensitive herbicide nanocapsule of example 1 of the present invention;

FIG. 2 is a transmission electron micrograph of the sunlight-sensitive herbicide nanocapsule of example 1 of the present invention after irradiation by sunlight;

FIG. 3 is a graph showing the release profile of the sunlight-exposed drug from the solar-sensitive herbicide nanocapsule of example 1 of the present invention;

FIG. 4 shows the safety evaluation results of the solar-sensitive herbicide nanocapsules of example 4 of the present invention in mice.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

The solar photosensitive type herbicide nanocapsule of the embodiment of the invention, and the preparation method and the application thereof are specifically described below.

The embodiment of the invention provides a sunlight sensitive type herbicide nanocapsule, which is mainly formed by self-assembling cucurbituril, methyl amethyst and 4-hexylazobenzene to form a nanocapsule loaded herbicide, and specifically comprises the following steps: the nanocapsule is formed by self-assembling cucurbituril, methyl amethyst and 4-hexyl azobenzene; and a herbicide loaded in the nanocapsule. The herbicide nanocapsule can respond to the stimulation of solar illumination to release the coated herbicide, so that the weeding effect is achieved. Wherein the molar ratio of cucurbituril to methyl amethyst to 4-hexylazobenzene is generally 1-2: 1-2: 1-2, preferably 1: 1: 1.

in this embodiment, the cucurbiturils are selected from cucurbiturils [8-10], for example, one or more selected from cucurbiturils [8], cucurbiturils [9], cucurbiturils [10], particularly cucurbiturils [8 ]. Cucurbituril is a macrocyclic host molecule, compared with cyclodextrin, the cucurbituril has stronger combination with a plurality of guest molecules, and in the aspect of a drug delivery system, the cucurbituril can be used for constructing an amphiphilic supramolecular complex and further assembled into an intelligent nano drug delivery system, and can respond to different external stimuli (pH, temperature, illumination and the like) to achieve the purpose of controlling the release of drugs.

In this embodiment, the herbicide is selected from any one of paraquat, diquat, alachlor, acetochlor, glufosinate and glyphosate. The weight concentration of the herbicide in the herbicide nanocapsule is more than 0 and less than or equal to 5 percent, such as more than or equal to 0.1 percent and less than or equal to 4.5 percent, or more than or equal to 0.5 percent and less than or equal to 4 percent, or more than or equal to 0.8 percent and less than or equal to 3.5 percent, or more than or equal to 1 percent and less than or equal to 3 percent.

In this example, 4-hexylazobenzene is used as a trans-alkylazobenzene, primarily in response to ultraviolet light in the sun, causing the nanocapsules to rupture and release the encapsulated herbicide. In addition, the longer alkyl chain constitutes the hydrophobic end of the supramolecular complex, thereby facilitating self-assembly into nanocapsule structures. The alkylazobenzenes have the structure of formula I:

in the formula I, x can be an integer more than or equal to 3.

In this embodiment, specifically, 4-hexylazobenzene (trans-azobenzene) and methyl amethyst are used as guest molecules, cucurbituril is used as host molecules, and the formed compound is excited by ultraviolet light, so that the trans-azobenzene is converted into cis-azobenzene, and comes out from the cavity of the host molecules. The sunlight response type nano-capsule constructed by taking cucurbituril as a main molecule is used as a basis, and the herbicide is used as a model drug to form a sunlight response type herbicide nano-capsule drug delivery system which can be used as a novel 'green herbicide' which is safe and harmless to users and still has a good weeding effect. Compared with the existing high-toxicity herbicide on the market, the sunlight-sensitive herbicide nanocapsule can obviously reduce the toxicity and keep the weeding effect.

The embodiment of the invention also provides a preparation method of the solar photosensitive herbicide nanocapsule, which comprises the following steps:

first, cucurbituril, methyl amethyst and herbicide are dissolved in water sufficiently.

Secondly, slowly dripping an organic solvent solution of 4-hexylazobenzene, fully stirring for more than or equal to 0.5 hour, forming a photosensitive amphiphilic compound by the interaction of cucurbituril, methyl amethyst and 4-hexylazobenzene through host-guest, and realizing the loading of the herbicide in the process of self-assembling to form the nanocapsule. Wherein the organic solvent is at least one of ethanol, acetone, N-dimethylformamide and dimethyl sulfoxide, and the organic solvent solution of 4-hexylazobenzene can be prepared from 4-hexylazobenzene and a single-component solvent, or can be prepared from 4-hexylazobenzene and a multi-component solvent.

Then, fully dialyzing in water to remove the organic solvent, wherein the dialysis method comprises the steps of transferring the solution formed after fully stirring into a dialysis bag, and dialyzing with water to obtain the aqueous solution of the sunlight-sensitive herbicide nanocapsule, and the product can be directly used. The dialyzed solution can be filtered by a microporous filter membrane with the aperture of 0.4-0.5 mu m, and then freeze-dried to form a powdery product which is convenient to store and transport, and the aqueous solution of the solar-sensitive herbicide nanocapsule can be prepared before use.

The preparation method of the sunlight-sensitive herbicide nanocapsule is simple in process, can be prepared in one pot, does not need a surfactant, and almost has no organic solvent residue.

The embodiment of the invention also provides application of the solar-sensitive type herbicide nanocapsule, wherein the herbicide nanocapsule is applied to the surface of a plant and is irradiated by sunlight, specifically, an aqueous solution (directly prepared aqueous solution or prepared powder which is prepared by adding water) of the herbicide nanocapsule is sprayed on the surface of the plant and is irradiated by the sunlight for more than or equal to 2 hours generally, so that the weeding effect can be achieved, and the solar-sensitive type herbicide nanocapsule can be used as a substitute of a toxic herbicide in the market.

The features and properties of the present invention are described in further detail below with reference to examples.