Mosquito luring agent gel composition as well as preparation method and application thereof

Abstract

The invention discloses a mosquito luring agent gel composition as well as a preparation method and application thereof, and relates to the technical field of daily chemical industry. The composition provided by the invention has a gel dosage form and comprises a gel matrix and a long-acting mosquito-luring component, the long-acting mosquito-luring active component is mainly tea-flavor ketone, meanwhile, sodium benzoate is added to be compounded with the tea-flavor ketone, and the sodium benzoate can realize slow release of the tea-flavor ketone through intermolecular interaction with the tea-flavor ketone. Meanwhile, the introduction of sodium benzoate can also adjust the microstructure of the obtained gel, has important influence on the texture of the gel, and can improve the stability of the gel. Based on the introduction of sodium benzoate and the gel formulation, the water-retaining property of the gel and the slow release of tea flavor ketone are remarkably improved, the durability of mosquito trapping activity is prolonged, the mosquito trapping rate within 72 hours is stabilized to be 58% or above, the reduction degree is not higher than 27.5% compared with the mosquito trapping rate after 24 hours, and the gel has excellent large-scale application prospects.

Description

Technical Field

[0001] This invention relates to the field of daily chemical technology, specifically to a mosquito attractant gel composition, its preparation method, and its application. Background Technology

[0002] With global warming and rapid urbanization, the breeding and disease transmission of mosquitoes and other pests are becoming increasingly serious problems. Mosquitoes are the main vectors for diseases such as malaria, dengue fever, and Zika virus, posing a serious threat to human health and safety. Currently, most mosquito control products on the market are insect repellents and insecticides. However, while these products can quickly reduce mosquito numbers, most leave residues in the environment, potentially posing a threat to humans, livestock, and other organisms, and mosquitoes are prone to developing resistance. In contrast, mosquito attractants have relatively higher targeting effectiveness and safety, but typically have a shorter lifespan. Therefore, there is a need to provide a mosquito attractant product with a longer lifespan to meet societal needs. Summary of the Invention

[0003] To address the shortcomings of existing technologies, the present invention provides a mosquito attractant gel composition.

[0004] The above-mentioned objective of this invention is achieved through the following technical solution: A mosquito attractant gel composition comprising a gel matrix and a long-lasting mosquito attractant component, wherein the long-lasting mosquito attractant component comprises sodium benzoate and tea ketone (2,6,6-trimethyl-2-cyclohexene-1,4-dione, hereinafter referred to as tea ketone) in a mass ratio of (0.1-3):1.

[0005] This invention provides a gel-form mosquito attractant composition, using sodium benzoate and tea ketone as long-lasting mosquito attractant components, significantly improving the duration of mosquito attractant gel activity. Generally, tea ketone needs a certain degree of volatility to ensure its full mosquito-attracting effect. Therefore, while tea ketone has excellent mosquito-attracting activity as an active component, its volatility leads to poor retention of the mosquito attractant in actual use. To address this, this invention introduces the synergistic effect of sodium benzoate and tea ketone. Sodium benzoate is commonly used as a preservative; however, the inventors of this application, through extensive experimental research, discovered that the effect of sodium benzoate in this invention far exceeds its conventional preservative function. This is presumably because the benzene ring in sodium benzoate can generate π-π stacking interactions with tea ketone, which has a conjugated molecular structure. Simultaneously, sodium benzoate has excellent water solubility, and the intermolecular interaction between the two promotes the solubility of tea ketone in water and its slow release during use.

[0006] In addition to its synergistic effect with tea flavor ketone, sodium benzoate also plays a role in regulating the gel microstructure in this application. Sodium benzoate has ionic properties and significantly affects the aggregation state of gelling agent molecules; therefore, its concentration has a significant impact on the texture (hardness, elasticity, and dehydration shrinkage) of the final gel. Therefore, in this invention, the ratio of tea flavor ketone to sodium benzoate needs to be specifically controlled at 1:(0.1-3).

[0007] Preferably, the concentration of the long-acting mosquito-attracting component in the gel matrix is ​​0.6-6 wt%.

[0008] More preferably, the concentration of the long-acting mosquito-attracting component in the gel matrix is ​​2-5 wt%.

[0009] By adjusting the concentration of the long-acting mosquito-attracting component in the gel matrix, a more suitable gel structure can be obtained, which is one of the core keys to achieving an ideal gel state (neither too hard and brittle, nor too soft and water-permeable). This ideal physical state is also crucial for controlling the release rate of tea fragrance ketones and maintaining the long-term stability of the gel in an open environment.

[0010] Preferably, the gel matrix comprises a gelling agent and a solvent, wherein the gelling agent comprises a polysaccharide gelling agent.

[0011] More preferably, the polysaccharide gelling agent comprises a heteropolysaccharide. More preferably, the heteropolysaccharide comprises agar.

[0012] Using heteropolysaccharides like agar as a gelling agent results in a hydrogel with high strength. The three-dimensional network structure formed effectively encapsulates tea aroma ketone molecules, significantly slowing their volatilization (compared to emulsions and powders). Compared to other common gelling agents in the field, such as gelatin, carrageenan, and sodium carboxymethyl cellulose (CMC), this invention uses heteropolysaccharides to obtain a more stable, durable gel system with better compatibility with tea aroma ketones, thus improving its long-lasting effect.

[0013] Preferably, the gel matrix further includes processing aids, which include at least one of emulsifiers, solubilizers, and thickeners.

[0014] Preferably, the mass ratio of the gelling agent to the solvent is (1-3):(50-80).

[0015] Preferably, the emulsifier has an HLB value of 12-17.

[0016] In a specific embodiment of the present invention, the HLB value of the emulsifier can be directly calculated using the Griffin formula or obtained by consulting the product technical parameter table provided by the supplier.

[0017] More preferably, the emulsifier includes a nonionic emulsifier.

[0018] More preferably, the nonionic emulsifier includes polyoxyethylene sorbitan monooleate (Tween 80).

[0019] The HLB value of polyoxyethylene dehydrated sorbitan monooleate is 15. A moderate HLB value (hydrophilic-lipophilic balance value) can effectively improve the apparent solubility of tea ketone in the aqueous phase and play a "lubricating" role in the formation of gel network, which helps to form a more uniform and dense gel structure, thereby better controlling the slow release of tea ketone.

[0020] Preferably, the co-solvent includes ethanol.

[0021] Preferably, the thickener comprises glucose.

[0022] Glucose not only thickens the gel but also acts as a secondary attractant to attract mosquitoes. More importantly, its molecular structure helps maintain the gel's osmotic pressure balance and moisture retention, reducing water evaporation and shrinkage (dehydration shrinkage) in open environments, thereby maintaining the integrity of the gel structure and its duration of effectiveness.

[0023] Preferably, the solvent includes water.

[0024] Preferably, the mosquito attractant gel composition comprises the following components in parts by weight: 1-3 parts gelling agent, 1-3 parts emulsifier, 5-15 parts cosolvent, 0.2-2 parts sodium benzoate, 0.5-1.5 parts tea flavor ketone, 5-8 parts thickener, and 50-80 parts solvent.

[0025] Ethanol can be used as a co-solvent to improve the dispersibility of tea flavor ketone in the gel system, but its amount must be controlled within a specific range to avoid significantly affecting the solubility of sodium benzoate.

[0026] More preferably, the gelling agent is present in the composition at a mass percentage of 1%-5%.

[0027] Preferably, the average pore diameter of the gel composition, as measured by SEM, is 100-500 μm.

[0028] The pore diameter has a sustained-release effect on the volatile components (mainly tea aroma ketones) in the gel. In the porous gel of this invention, the intricate pores act as a "maze," increasing the path for tea aroma ketones to evaporate into the air, thus further improving the sustained-release effect and enhancing the gel's durability.

[0029] It should be noted that the pore size data obtained from the gel varies depending on the method used. This application uses data obtained under SEM. The sample preparation method is as follows: the gel sample is sliced, freeze-dried, sputter-coated with gold, and observed using a scanning electron microscope at an accelerating voltage of 15 keV. At least 5 regions are selected, and 3 pores are randomly selected from each region to measure the average pore diameter; the magnification is 200x.

[0030] The present invention also provides a method for preparing the above-mentioned mosquito attractant gel composition, comprising the following steps: Mix all components thoroughly and allow to stand to gel, and you will get the product.

[0031] Preferably, the static gelation temperature is 30-45℃.

[0032] The present invention also protects the use of the above-described mosquito attractant gel composition in the field of mosquito attraction.

[0033] Compared with the prior art, the present invention has the following beneficial effects: By combining sodium benzoate with tea ketone, this invention significantly improves the water retention of the gel and the sustained release of tea ketone, prolonging the duration of mosquito-attracting activity. The mosquito-catching rate remains stable at over 58% within 72 hours, and the decrease in mosquito-catching rate compared to 24 hours is no more than 27.5%, showing excellent prospects for large-scale application. Attached Figure Description

[0034] Figure 1 This is a SEM image of the tea-scented ketone gel obtained in Example 1 of the present invention.

[0035] Figure 2 This is a picture of the finished product of the tea-scented ketone gel obtained in Example 1 of the present invention.

[0036] Figure 3 This is a picture of the finished product of the tea-scented ketone gel obtained in Example 2 of the present invention.

[0037] Figure 4 This is a picture of the finished product of the tea-scented ketone gel obtained in Example 6 of the present invention.

[0038] Figure 5 This is a picture of the finished product of the tea-scented ketone gel obtained in Example 7 of the present invention.

[0039] Figure 6 This is a schematic diagram of the mosquito-trapping effect of the tea-scented ketone gel obtained in Example 1 of the present invention at 0h.

[0040] Figure 7 This is a schematic diagram showing the mosquito-trapping effect of the tea-scented ketone gel obtained in Example 1 of the present invention after 24 hours.

[0041] Figure 8 This is a finished product image of the tea-flavor ketone emulsion obtained in Comparative Example 1 of the present invention.

[0042] Figure 9 This is a finished product image of the tea-flavor ketone powder obtained in Comparative Example 2 of the present invention. Detailed Implementation

[0043] The present invention will be further described below with reference to specific embodiments, but the embodiments do not limit the present invention in any way. Unless otherwise stated, the raw materials and reagents used in the embodiments of the present invention are conventionally purchased raw materials and reagents.

[0044] Example 1 A mosquito attractant gel composition comprising the following components in parts by weight: The composition comprises 1.5 parts agar powder (gelling agent), 1 part Tween 80, 10 parts anhydrous ethanol (co-solvent), 1.5 parts sodium benzoate, 1 part tea flavoring ketone, 7.7 parts glucose (thickener), and 77 parts water (solvent). The gelling agent accounts for 1.5% of the total mass of the composition.

[0045] The preparation method of the mosquito attractant gel composition in this embodiment includes the following steps: Mix all components thoroughly and allow to stand at 35°C to gel, and the product is ready.

[0046] The mosquito attractant gel composition prepared in this embodiment was characterized by SEM, and the results are as follows: Figure 1 As shown, the average pore diameter of the obtained gel composition, as measured by SEM, is ~200 μm.

[0047] Example 2 A mosquito attractant gel composition comprising the following components in parts by weight: 1 part gelling agent agar powder, 1 part Tween 80, 5 parts cosolvent anhydrous ethanol, 2 parts sodium benzoate, 0.5 parts tea flavor ketone, 5 parts thickener glucose, and 50 parts solvent water.

[0048] The preparation method of the mosquito attractant gel composition in this embodiment is carried out in accordance with Example 1.

[0049] Example 3 A mosquito attractant gel composition comprising the following components in parts by weight: The ingredients are: 3 parts gelling agent agar powder, 3 parts Tween 80, 15 parts cosolvent anhydrous ethanol, 0.2 parts sodium benzoate, 1.5 parts tea flavor ketone, 8 parts thickener glucose, and 80 parts solvent water.

[0050] The preparation method of the mosquito attractant gel composition in this embodiment is carried out in accordance with Example 1.

[0051] Example 4 A mosquito attractant gel composition comprising the following components in parts by weight: The gelling agent is 1.5 parts agar powder, Tween 80 is 1 part, the solubilizer is anhydrous ethanol is 10 parts, sodium benzoate is 4 parts, tea flavor ketone is 2.66 parts, the thickener is glucose is 7.7 parts, and the solvent is water is 77 parts.

[0052] The preparation method of the mosquito attractant gel composition in this embodiment is carried out in accordance with Example 1.

[0053] Example 5 A mosquito attractant gel composition comprising the following components in parts by weight: The ingredients are: 1.5 parts gelling agent (agar powder), 1 part Tween 80, 10 parts cosolvent (anhydrous ethanol), 0.3 parts sodium benzoate, 0.2 parts tea flavor ketone, 7.7 parts thickener (glucose), and 77 parts solvent (water).

[0054] The preparation method of the mosquito attractant gel composition in this embodiment is carried out in accordance with Example 1.

[0055] Example 6 A mosquito attractant gel composition, wherein the only difference from Example 1 is: Replace Tween 80 with an equal amount of Span 80 (HLB 4.3, nonionic emulsifier).

[0056] The preparation method of the mosquito attractant gel composition in this embodiment is carried out in accordance with Example 1.

[0057] Example 7 A mosquito attractant gel composition, wherein the only difference from Example 1 is: Replace Tween 80 with an equal amount of CTAB (HLB 16, a cationic emulsifier).

[0058] The preparation method of the mosquito attractant gel composition in this embodiment is carried out in accordance with Example 1.

[0059] The mosquito attractant gel compositions prepared in Examples 2-7 were characterized by SEM. The average pore diameter of the obtained gel compositions measured by SEM was in the range of 100-500 μm.

[0060] Example 8 A mosquito attractant gel composition, wherein the only difference from Example 1 is: The gelling agent comprises 10 parts by weight, and the water comprises 68.5 parts by weight. The gelling agent accounts for 10.03% by weight in the composition.

[0061] The preparation method of the mosquito attractant gel composition in this embodiment is carried out in accordance with Example 1.

[0062] The mosquito attractant gel composition prepared in this embodiment was characterized by SEM. The pore diameter of the obtained gel composition measured by SEM was 20-100 μm.

[0063] Example 9 A mosquito attractant gel composition, wherein the only difference from Example 1 is: The gelling agent comprises 0.5 parts by weight, and the water comprises 78 parts by weight. The gelling agent accounts for 0.5% by weight of the composition.

[0064] The preparation method of the mosquito attractant gel composition in this embodiment is carried out in accordance with Example 1.

[0065] The mosquito attractant gel composition prepared in this embodiment was characterized by SEM. The pore diameter of the obtained gel composition was measured to be 600-800 μm by SEM.

[0066] Comparative Example 1 A mosquito attractant composition comprising the following components in parts by weight: 5 parts Tween 80, 10 parts liquid paraffin, 1.5 parts sodium benzoate, 1 part tea ketone, and 82.5 parts solvent water.

[0067] The resulting composition is an emulsion formulation.

[0068] The preparation method of the mosquito attractant composition in this comparative example includes the following steps: Tea fragrance ketone was dissolved in liquid paraffin (oil phase). Tween 80 and sodium benzoate were dissolved in deionized water (aqueous phase). Under high-speed stirring (1000 rpm), the oil phase was slowly added to the aqueous phase, and stirring was continued until a uniform milky white emulsion was formed.

[0069] Comparative Example 2 A mosquito attractant composition comprising the following components in parts by weight: 10 parts precipitated silica, 1 part tea ketone, and 87.5 parts glucose.

[0070] The resulting composition is in powder form.

[0071] The preparation method of the mosquito attractant composition in this comparative example includes the following steps: Sodium benzoate is mixed with a small amount of glucose powder and ground evenly. Tea ketone is mixed with fumed silica and ground thoroughly to adsorb the ketone. The fumed silica that has adsorbed tea ketone is mixed with the remaining glucose powder and the premixed sodium benzoate-glucose powder and ground thoroughly until a uniform powder is formed.

[0072] Comparative Example 3 A mosquito attractant gel composition, wherein the only difference from Example 1 is: Replace sodium benzoate with an equal amount of potassium sorbate.

[0073] The preparation method of the mosquito attractant gel composition in this comparative example was carried out according to Example 1.

[0074] Comparative Example 4 A mosquito attractant gel composition, wherein the only difference from Example 1 is: Replace sodium benzoate with an equal amount of methylparaben.

[0075] The preparation method of the mosquito attractant gel composition in this comparative example was carried out according to Example 1.

[0076] Comparative Example 5 A mosquito attractant gel composition, wherein the only difference from Example 1 is: Replace sodium benzoate with an equal amount of butylated hydroxytoluene.

[0077] The preparation method of the mosquito attractant gel composition in this comparative example was carried out according to Example 1.

[0078] Comparative Example 6 A mosquito attractant gel composition, wherein the only difference from Example 1 is: The mass fraction of sodium benzoate is 2.3 parts, and the mass fraction of tea aroma ketone is 0.2 parts.

[0079] The preparation method of the mosquito attractant gel composition in this comparative example was carried out according to Example 1.

[0080] Comparative Example 7 A mosquito attractant gel composition, wherein the only difference from Example 1 is: The sodium benzoate has a mass fraction of 0.2 parts, and the tea aroma ketone has a mass fraction of 2.3 parts.

[0081] The preparation method of the mosquito attractant gel composition in this comparative example was carried out according to Example 1.

[0082] Comparative Examples 6-7 are intended to illustrate that even if the total concentration of the mosquito-attracting components is within the range of the present invention, the effect will be significantly reduced when the mass ratio of sodium benzoate to tea ketone deviates from the requirement of (0.1-3):1 of the present invention.

[0083] Performance testing I. Basic Testing of the Composition Volatilization weight loss test (25±1℃, relative humidity 65±5%): Equal masses (approximately 10g) of the three dosage forms were weighed and placed in open petri dishes (9cm in diameter) of the same size. After 48 hours, the samples were weighed and the weight loss rate (%) was calculated. The weight loss mainly reflects the loss of the volatile component, tea aroma ketone.

[0084] Physical stability test (dehydration shrinkage rate): Weigh a certain mass (approximately 10g) of gel sample and place it in a sealed weighing bottle with sufficient dry filter paper at the bottom. After standing at 25℃ for 48 hours, remove the gel, gently blot the surface moisture with filter paper, and weigh it. Calculate the dehydration shrinkage rate (%) = (initial mass - final mass) / initial mass × 100%. This index mainly reflects the tendency of the gel network structure to expel water due to shrinkage, directly characterizing its structural stability.

[0085] Dispersion state and gel appearance test: visual observation.

[0086] The test results are shown in Table 1 below: Table 1. As can be seen from Table 1 above, the mosquito attractant gel composition prepared in this application has an ideal morphology of uniform semi-transparent or transparent gel, and has excellent water retention stability and sustained release properties of tea fragrance ketone. The volatile weight loss rate within 48 hours is not higher than 12%, and the dehydration shrinkage rate is not higher than 6%, which provides a good foundation for its subsequent application.

[0087] II. Long-lasting mosquito attraction effect test Equal amounts of the example and comparative samples (containing 10 mg of tea ketone), as well as a blank control UV lamp trapping device without attractant, were placed in the center of a standard mosquito net (120cm×200cm×60cm). Fifty hungry female Aedes albopictus mosquitoes were released into the mosquito net, and the number of mosquitoes in the trapping device was recorded after 24 hours. After 24 hours, the number of Aedes albopictus mosquitoes in the mosquito net was replenished to 50, and the mosquito capture count was tested after 48 hours. After 48 hours, the number of mosquitoes was replenished again to test the mosquito capture count after 72 hours of sample placement. The sample without tea ketone was used as a blank control group.

[0088] The test results are shown in Table 2 below: Table 2. Group 24-hour mosquito trapping rate (%) 48-hour mosquito trapping rate (%) 72-hour mosquito trapping rate (%) Example 1 88 84 80 Example 2 86 82 78 Example 3 84 80 78 Example 4 90 82 76 Example 5 70 66 60 Example 6 80 76 72 Example 7 82 80 74 Example 8 76 74 72 Example 9 80 72 58 Comparative Example 1 70 58 46 Comparative Example 2 60 52 44 Comparative Example 3 70 62 54 Comparative Example 4 68 60 52 Comparative Example 5 64 56 48 Comparative Example 6 66 58 50 Comparative Example 7 84 60 38 Blank control 34 38 32 As shown in Table 2 above, the mosquito attractant gel composition prepared by this invention has long-lasting mosquito-attracting activity, with a mosquito trapping rate of over 58% within 72 hours. Compared with the mosquito trapping rate after 24 hours of use, the decrease is no more than 27.5% [the calculation formula is (72-hour mosquito trapping rate - 24-hour mosquito trapping rate) / 24-hour mosquito trapping rate]. Its persistence is similar to that of ultraviolet lamp trapping devices that require continuous power, while the activity is more than twice as high, showing excellent prospects for large-scale application.

[0089] Based on Tables 1-2 and the data from Examples 1 and 4-5, it can be seen that when the ratio of sodium benzoate to tea ketone in the long-acting mosquito-attracting component remains unchanged, the concentration of the long-acting mosquito-attracting component in the gel matrix is ​​preferably 0.6-6 wt% (Example 1), which is beneficial to obtain a gel with a more ideal structure (better hardness, elasticity, etc.). However, when the proportion of the mosquito-attracting component is too high (Example 4), although the initial mosquito-attracting activity is higher, the gel structure is not ideal, resulting in a decrease in the duration of effectiveness.

[0090] According to Examples 1 and 6-7, improper selection of the type of emulsifier or HLB value can also affect the structure of the formed gel, resulting in a certain degree of decrease in the sustained-release effect of tea fragrance ketone and the water-retaining effect of the gel.

[0091] According to Examples 1 and 8-9, the content of gelling agent in the composition of the present invention affects the pore structure of the gel. A suitable pore structure is beneficial to prolonging the release path of the long-acting mosquito-attracting component, thereby further improving the sustained-release effect.

[0092] According to Comparative Examples 1 and 2, emulsion and powder formulations of mosquito attractants cannot achieve the long-lasting effect of gel formulations.

[0093] According to Comparative Examples 3-5, replacing sodium benzoate with other common preservatives in the art, such as methylparaben and butylated hydroxytoluene, did not achieve the effect of this application. This is because sodium benzoate has unique ionization characteristics and a relatively simple structure, and has a higher tendency to undergo π-π stacking effect, which has a unique role when compounded with tea aroma ketone.

[0094] According to Comparative Examples 6-7, the total amount of long-lasting mosquito-attracting active ingredients remains unchanged, but the ratio of two of the substances is not appropriate, which will lead to the inability to achieve both a good gel structure and long-lasting mosquito-attracting activity.

[0095] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A mosquito attractant gel composition, characterized in that, The composition comprises a gel matrix and a long-lasting mosquito-attracting component, wherein the long-lasting mosquito-attracting component comprises sodium benzoate and tea ketone in a mass ratio of (0.1-3):

1.

2. The mosquito attractant gel composition as described in claim 1, characterized in that, The concentration of the long-acting mosquito-attracting component in the gel matrix is ​​0.6-6 wt%.

3. The mosquito attractant gel composition as described in claim 1, characterized in that, The gel matrix comprises a gelling agent and a solvent, wherein the gelling agent comprises a polysaccharide gelling agent.

4. The mosquito attractant gel composition as described in claim 3, characterized in that, The gel matrix further includes processing aids, which include at least one of emulsifiers, solubilizers, and thickeners; And / or, the mass ratio of the gelling agent to the solvent is (1-3):(50-80).

5. The mosquito attractant gel composition as described in claim 4, characterized in that, The HLB value of the emulsifier is 12-17; And / or, the emulsifier includes a nonionic emulsifier.

6. The mosquito attractant gel composition as described in claim 4, characterized in that, The co-solvent includes ethanol; And / or, the thickener includes glucose; And / or, the solvent includes water; And / or, the mosquito attractant gel composition comprises the following components in parts by weight: 1-3 parts gelling agent, 1-3 parts emulsifier, 5-15 parts cosolvent, 0.2-2 parts sodium benzoate, 0.5-1.5 parts tea flavor ketone, 5-8 parts thickener, and 50-80 parts solvent.

7. The mosquito attractant gel composition according to any one of claims 1-6, characterized in that, The average pore diameter of the gel composition, as measured by SEM, is 100-500 μm.

8. A method for preparing the mosquito attractant gel composition according to any one of claims 1-7, characterized in that, The process includes the following steps: mix all components thoroughly, allow to stand and gel, and the product is obtained.

9. The preparation method according to claim 8, characterized in that, The static gelation temperature is 30-45℃.

10. The use of the mosquito attractant gel composition according to any one of claims 1-7 in the field of mosquito attraction.

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