A composite disinfectant containing chlorine dioxide and its preparation process

Abstract

The present invention provides a composite disinfectant containing chlorine dioxide and its preparation process, belonging to the technical field of composite disinfectant preparation; the preparation process includes the following steps: preparation of a carrier stabilizer; preparation of modified carboxymethyl chitosan; preparation of slow-release gel microspheres; preparation of modified chitosan derivatives; preparation of a chlorine dioxide composite disinfectant. The chlorine dioxide composite disinfectant prepared by the present invention can avoid the initial burst release of the slow-release gel microspheres, enable the slow and stable release of the chlorine dioxide component, play a lasting and efficient disinfection and antibacterial role, and can reduce the corrosion of chlorine dioxide to metals.

Description

Technical Field

[0001] The present invention relates to the technical field of composite disinfectant preparation, and particularly relates to a composite disinfectant containing chlorine dioxide and its preparation process. Background Art

[0002] As a highly efficient and broad-spectrum disinfectant, chlorine dioxide can kill almost all microorganisms including bacteria, fungi, and viruses, and no carcinogenic substances will be produced after disinfection. Its strong oxidizing property enables it to be widely used in many fields. For example, in the water treatment field, it can effectively purify drinking water, remove odors and pigments in water, and at the same time show high-efficiency bactericidal and virucidal capabilities at low concentrations. Its sterilization effect is significantly better than that of chlorine and sodium chlorite, and its ability to inhibit viruses is also higher than that of chlorine and stronger than that of ozone. In the field of healthcare, it can be used for the disinfection treatment of hospital sewage, effectively killing pathogens and making the treated sewage meet the relevant national standards; in the food industry, it can disinfect food factories, beverage factories, meat factories, etc. to ensure food safety; in other fields such as the petroleum industry, it also plays an important disinfection role.

[0003] However, chlorine dioxide itself has some insurmountable defects. On the one hand, it is extremely unstable and extremely sensitive to light, and it is extremely easy to degrade under sunlight irradiation, which brings great difficulties to its transportation and storage and limits its application scope. On the other hand, as a strong oxidant, early research believed that it has relatively strong corrosiveness, and ordinary stainless steel materials will be eroded, which hinders its large-scale popularization and application.

[0004] In view of the pain point of the instability of chlorine dioxide, gas slow-release materials have become an important technical direction for improving the disinfection effect due to their advantages such as enabling the continuous release of chlorine dioxide, extending the disinfection time limit, and reducing frequent dosing operations. Although gas slow-release materials have many practical applications, some currently commercial gas slow-release materials still have problems such as sudden gas release and unstable gas slow-release rate during the release process.

[0005] Therefore, we propose a composite disinfectant containing chlorine dioxide and its preparation process that can slow down sudden gas release, improve stability, and slow down corrosion. Summary of the Invention

[0006] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide a composite disinfectant containing chlorine dioxide and its preparation process.

[0007] A preparation process of a composite disinfectant containing chlorine dioxide includes the following steps:

[0008] S1: Preparation of carrier stabilizer

[0009] Prepare a carrier stabilizer by mixing sodium hydroxide, sodium aluminate and deionized water, and then adding sodium silicate nonahydrate.

[0010] S2: Preparation of modified carboxymethyl chitosan

[0011] Prepare modified carboxymethyl chitosan by mixing 3-carboxy-5-nitrophenylboronic acid, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, N-hydroxysuccinimide and dimethyl sulfoxide to modify carboxymethyl chitosan.

[0012] S3: Preparation of sustained-release gel microspheres

[0013] Add the carrier stabilizer to deionized water, then add the modified carboxymethyl chitosan solution and sodium chlorite to obtain a mixed system. Drop the mixed system into zinc nitrate hexahydrate solution using a dropper, and then add it to tannic acid solution. Freeze-dry to obtain sustained-release gel microspheres.

[0014] S4: Preparation of modified chitosan derivatives

[0015] Prepare modified chitosan derivatives by modifying chitosan cinnamaldehyde Schiff base with 5-chloromethyl-8-hydroxyquinoline hydrochloride.

[0016] S5: Preparation of chlorine dioxide composite disinfectant

[0017] Dissolve the modified chitosan derivative in acetic acid solution, then add lithium magnesium silicate activation solution to obtain a coating solution. Spray the coating solution onto the sustained-release gel microspheres in a sugar coating machine, and then freeze-dry to obtain the chlorine dioxide composite disinfectant.

[0018] Furthermore, the preparation of the carrier stabilizer in step S1 specifically includes the following steps:

[0019] S1.1: Mix 2-3 parts by weight of sodium hydroxide, 0.5-0.8 parts by weight of sodium aluminate and 29-32 parts by weight of deionized water, and then stir at 2000-3000 r / min for 20-30 min to obtain a mixed solution.

[0020] S1.2: Add 3.81-4.23 parts by weight of sodium silicate nonahydrate to the mixed solution, stir and mix for 6-8 h, then put it into a stainless steel autoclave and react at 80-82 °C for 14-15 h. Then wash with deionized water until neutral, vacuum dry, and then react in a nitrogen atmosphere at 500-520 °C for 4-5 h, and then grind and pulverize to obtain the carrier stabilizer.

[0021] Furthermore, the preparation of the modified carboxymethyl chitosan in step S2 specifically includes the following steps:

[0022] S2.1: Add 0.6 - 0.8 parts by weight of 3 - carboxy - 5 - nitrobenzeneboronic acid, 0.52 - 0.69 parts by weight of 1 - ethyl - (3 - dimethylaminopropyl) carbodiimide hydrochloride, and 0.33 - 0.46 parts by weight of N - hydroxysuccinimide to 30 - 35 parts by weight of dimethyl sulfoxide, and stir and mix at 200 - 300 r / min for 4 - 5 h to obtain an activation solution;

[0023] S2.2: Add 3 - 5 parts by weight of carboxymethyl chitosan to 400 - 420 parts by weight of deionized water, and stir and mix for 20 - 30 min to obtain a carboxymethyl chitosan solution;

[0024] S2.3: Use a syringe to drop the activation solution into the carboxymethyl chitosan solution, stir at room temperature for 10 - 12 h, then add 0.1 M sodium hydroxide solution to adjust the pH to 9 - 9.2, then put it into a dialysis bag and dialyze for 3 - 4 d, changing the water every 4 - 5 h during the period. After dialysis is completed, perform freeze - drying to obtain modified carboxymethyl chitosan.

[0025] Further, the preparation of the sustained - release gel microspheres in step S3 specifically includes the following steps:

[0026] S3.1: Add 3 - 5 parts by weight of modified carboxymethyl chitosan to deionized water, stir and mix for 20 - 30 min to obtain a 4 wt% modified carboxymethyl chitosan solution. Add 2 - 3 parts by weight of tannic acid to phosphate - buffered saline solution, and stir and mix for 20 - 30 min to obtain a 5 wt% tannic acid solution;

[0027] S3.2: Add 2 - 3 parts by weight of a carrier stabilizer to 10 - 12 parts by weight of deionized water, ultrasonicate for 20 - 30 min to obtain a mixture, then add the 4 wt% modified carboxymethyl chitosan solution and sodium chlorite, and stir at room temperature for 1 - 2 h to obtain a mixed system;

[0028] S3.3: Drop the mixed system into 12 - 15 parts by weight of a 10% zinc nitrate hexahydrate solution using a dropper, then add it to the 5 wt% tannic acid solution, mix for 3 - 5 min, and perform freeze - drying to obtain the sustained - release gel microspheres.

[0029] Further, the preparation of the modified chitosan derivative in step S4 specifically includes the following steps:

[0030] S4.1: Mix 10 - 12 parts by weight of 8 - hydroxyquinoline, 11 - 13 parts by weight of concentrated hydrochloric acid, and 11 - 13 parts by weight of 37 wt% formaldehyde, then introduce hydrogen chloride gas at 25 - 28 °C, stir and react for 10 - 12 h, then perform suction filtration, washing, and drying to obtain 5 - chloromethyl - 8 - hydroxyquinoline hydrochloride;

[0031] S4.2: Add 1.38 - 1.42 parts by weight of chitosan cinnamaldehyde Schiff base to 100 - 120 parts by weight of 3% acetic acid solution, and conduct a swelling reaction for 1 - 2 h. Then add 1.78 - 1.83 parts by weight of 5 - chloromethyl - 8 - hydroxyquinoline hydrochloride, raise the temperature to 80 - 83 °C, and react for 24 - 28 h. Then add 10% sodium hydroxide solution to adjust the pH to neutral. Finally, conduct suction filtration, washing, and drying to obtain the modified chitosan derivative.

[0032] Further, the preparation of the chlorine dioxide composite disinfectant in step S5 specifically includes the following steps:

[0033] S5.1: Mix 2 - 3 parts by weight of lithium magnesium silicate with 30 - 38 parts by weight of deionized water evenly, place it in a water bath at 15 - 30 °C, stir, and let it stand at room temperature to obtain the lithium magnesium silicate activation solution;

[0034] S5.2: Add 2 - 4 parts by weight of the modified chitosan derivative to 10 - 12 parts by weight of 2 - 3% acetic acid solution, stir and mix at 200 - 300 r / min for 20 - 30 min, then add the lithium magnesium silicate activation solution, and stir and mix for 10 - 12 min to obtain the coating solution;

[0035] S5.3: Spray 32 - 45 parts by weight of the coating solution onto 10 - 12 parts by weight of the sustained - release gel microspheres in a sugar - coating machine, and then conduct freeze - drying to obtain the chlorine dioxide composite disinfectant.

[0036] Further, the addition amount of the 4 wt% modified carboxymethyl chitosan solution in step S3.1 is 8 - 10% (W / V) of the mixture.

[0037] Further, the addition amount of sodium chlorite in step S3.1 is 20 - 23% (W / V) of the mixture.

[0038] A chlorine - dioxide - containing composite disinfectant is prepared by the preparation process of any one of the chlorine - dioxide - containing composite disinfectants described above.

[0039] Compared with the prior art, the present invention has at least the following beneficial effects:

[0040] 1. The present invention prepares sustained - release gel microspheres encapsulating sodium chlorite to slowly release chlorine dioxide gas, thereby achieving the effect of long - lasting antibacterial. And a carrier stabilizer is added during the preparation of the sustained - release gel microspheres. The carrier stabilizer can shorten the gel time and strengthen the gelation performance of the material. After adding the carrier stabilizer, the gel stability can be improved, thereby increasing the sustained - release time, and it can avoid the initial burst release of the sustained - release gel microspheres, enabling them to release the chlorine dioxide component smoothly and slowly, and playing the disinfection and antibacterial role persistently and efficiently.

[0041] 2. When preparing the sustained-release gel microspheres of the present invention, zinc nitrate hexahydrate reaction is carried out first, and then it is added to the tannic acid solution. The modified carboxymethyl chitosan and Zn 2+ are quickly crosslinked into a gel to encapsulate chlorine dioxide gas. Then it is added to the tannic acid solution, and tannic acid further crosslinks with the modified carboxymethyl chitosan. The secondary crosslinking fills the pores of the primary network, forming a denser double network structure. The dense network structure can slow down the problems of sudden release of chlorine dioxide gas and unstable gas release rate, and further achieve the effect of steadily and slowly releasing chlorine dioxide. At the same time, Zn 2+ , tannic acid can produce a synergistic antibacterial effect with chlorine dioxide, improving the antibacterial ability of the disinfectant.

[0042] 3. The present invention can effectively improve the embedding stability by encapsulating the sustained-release gel microspheres with the encapsulating liquid, keeping the sustained-release gel microspheres in a stable state, thereby improving the stability of the chlorine dioxide composite disinfectant. At the same time, when the composite disinfectant solution is mixed with water and sprayed for disinfection, the surface coating layer swells in water, and the modified chitosan derivative in the coating layer will adsorb on the metal surface to form a protective film, slowing down the corrosion of metal materials by chlorine dioxide gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The drawings incorporated herein and constituting a part of the specification illustrate embodiments of the present invention and, together with the specification, are further used to explain the principles of the present invention and enable those skilled in the relevant art to implement and use the present invention.

[0044] Figure 1 It is a test chart of the sustained-release effect of Examples 1-3 and Comparative Examples 1-3, 6 of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0045] The preparation process of a chlorine dioxide-containing composite disinfectant provided by the present invention will be described in detail below in conjunction with the drawings and specific embodiments. At the same time, it is hereby explained that in order to make the embodiments more detailed, the following embodiments are the best and preferred embodiments. For some well-known technologies, those skilled in the art can also adopt other alternative methods for implementation; and the drawings part is only for more specific description of the embodiments and is not intended to specifically limit the present invention.

[0046] Example 1

[0047] A preparation process of a chlorine dioxide-containing composite disinfectant includes the following steps:

[0048] S1: Preparation of the carrier stabilizer

[0049] S1.1: Mix 2 parts by weight of sodium hydroxide, 0.5 part by weight of sodium aluminate and 29 parts by weight of deionized water, then stir at 2000 r / min for 20 min to obtain a mixed solution;

[0050] S1.2: Add 3.81 parts by weight of sodium silicate nonahydrate to the mixed solution, stir and mix for 6 h, then put it into a stainless steel autoclave, react at 80 °C for 14 h, then wash with deionized water until neutral, dry in vacuum, then react in a nitrogen atmosphere at 500 °C for 4 h, and then grind and pulverize to obtain a carrier stabilizer;

[0051] S2: Preparation of modified carboxymethyl chitosan

[0052] S2.1: Add 0.6 part by weight of 3-carboxy-5-nitrophenylboronic acid, 0.52 part by weight of 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride and 0.33 part by weight of N-hydroxysuccinimide to 30 parts by weight of dimethyl sulfoxide, stir and mix at 200 r / min for 4 h to obtain an activation solution;

[0053] S2.2: Add 3 parts by weight of carboxymethyl chitosan to 400 parts by weight of deionized water, stir and mix for 20 min to obtain a carboxymethyl chitosan solution;

[0054] S2.3: Use a syringe to drop the activation solution into the carboxymethyl chitosan solution, stir at room temperature for 10 h, then add 0.1 M sodium hydroxide solution to adjust the pH to 9, then put it into a dialysis bag, dialyze for 3 d, change the water every 4 h during this period, after dialysis is completed, carry out freeze-drying to obtain modified carboxymethyl chitosan;

[0055] S3: Preparation of sustained-release gel microspheres

[0056] S3.1: Add 3 parts by weight of modified carboxymethyl chitosan to deionized water, stir and mix for 20 min to obtain a 4 wt% modified carboxymethyl chitosan solution, add 2 parts by weight of tannic acid to phosphate buffered saline, stir and mix for 20 min to obtain a 5 wt% tannic acid solution;

[0057] S3.2: Add 2 parts by weight of the carrier stabilizer to 10 parts by weight of deionized water, sonicate for 20 min to obtain a mixture, then add 8% (W / V) of the 4 wt% modified carboxymethyl chitosan solution and 20% (W / V) sodium chlorite, stir at room temperature for 1 h to obtain a mixed system;

[0058] S3.3: Drop the mixed system into 12 parts by weight of a 10% zinc nitrate hexahydrate solution using a dropper, then add it to the 5 wt% tannic acid solution, mix for 3 min, and carry out freeze-drying to obtain sustained-release gel microspheres;

[0059] S4: Preparation of Modified Chitosan Derivative

[0060] S4.1: Mix 10 parts by weight of 8-hydroxyquinoline, 11 parts by weight of concentrated hydrochloric acid, and 11 parts by weight of 37 wt% formaldehyde. Then, introduce hydrogen chloride gas at 25 °C, stir and react for 10 h. After that, perform suction filtration, washing, and drying to obtain 5-chloromethyl-8-hydroxyquinoline hydrochloride;

[0061] S4.2: Add 1.38 parts by weight of chitosan cinnamaldehyde Schiff base to 100 parts by weight of acetic acid solution with a concentration of 3%. Carry out a swelling reaction for 1 h. Then, add 1.78 parts by weight of 5-chloromethyl-8-hydroxyquinoline hydrochloride, raise the temperature to 80 °C, and react for 24 h. After that, add a sodium hydroxide solution with a concentration of 10% to adjust the pH to neutral. Finally, perform suction filtration, washing, and drying to obtain the modified chitosan derivative;

[0062] S5: Preparation of Chlorine Dioxide Composite Disinfectant

[0063] S5.1: Mix 2 parts by weight of lithium magnesium silicate with 30 parts by weight of deionized water evenly, place it in a water bath at 15 °C, stir, and let it stand at room temperature to obtain a lithium magnesium silicate activation solution;

[0064] S5.2: Add 2 parts by weight of the modified chitosan derivative to 10 parts by weight of acetic acid solution with a concentration of 2%. Stir and mix at 200 r / min for 20 min. Then, add the lithium magnesium silicate activation solution and stir and mix for 10 min to obtain a coating solution;

[0065] S5.3: Spray 32 parts by weight of the coating solution onto 10 parts by weight of sustained-release gel microspheres in a sugar coating machine, and then perform freeze-drying to obtain the chlorine dioxide composite disinfectant.

[0066] Example 2

[0067] A preparation process of a composite disinfectant containing chlorine dioxide includes the following steps:

[0068] S1: Preparation of Carrier Stabilizer

[0069] S1.1: Mix 2 parts by weight of sodium hydroxide, 0.5 part by weight of sodium aluminate, and 29 parts by weight of deionized water. Then, stir at 3000 r / min for 30 min to obtain a mixed solution;

[0070] S1.2: Add 3.81 parts by weight of sodium silicate nonahydrate to the mixed solution, stir and mix for 8 h. Then, put it into a stainless steel high-pressure reaction kettle, react at 82 °C for 15 h. After that, wash with deionized water until neutral, perform vacuum drying, then react in a nitrogen atmosphere at 520 °C for 5 h, and then grind and crush to obtain the carrier stabilizer;

[0071] S2: Preparation of Modified Carboxymethyl Chitosan

[0072] S2.1: Add 0.6 parts by weight of 3-carboxy-5-nitrophenylboronic acid, 0.52 parts by weight of 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, and 0.33 parts by weight of N-hydroxysuccinimide to 30 parts by weight of dimethyl sulfoxide, and stir and mix at 300 r / min for 5 h to obtain an activation solution;

[0073] S2.2: Add 3 parts by weight of carboxymethyl chitosan to 400 parts by weight of deionized water, stir and mix for 30 min to obtain a carboxymethyl chitosan solution;

[0074] S2.3: Use a syringe to drop the activation solution into the carboxymethyl chitosan solution, stir at room temperature for 12 h, then add 0.1 M sodium hydroxide solution to adjust the pH to 9, then put it into a dialysis bag and dialyze for 4 d, changing the water every 5 h during dialysis. After dialysis is completed, perform freeze-drying to obtain modified carboxymethyl chitosan;

[0075] S3: Preparation of Sustained-release Gel Microspheres

[0076] S3.1: Add 3 parts by weight of modified carboxymethyl chitosan to deionized water, stir and mix for 30 min to obtain a 4 wt% modified carboxymethyl chitosan solution. Add 2 parts by weight of tannic acid to phosphate buffer solution, stir and mix for 30 min to obtain a 5 wt% tannic acid solution;

[0077] S3.2: Add 2 parts by weight of carrier stabilizer to 10 parts by weight of deionized water, ultrasonicate for 30 min to obtain a mixture, then add 8% (W / V) of the 4 wt% modified carboxymethyl chitosan solution and 20% (W / V) sodium chlorite, and stir at room temperature for 2 h to obtain a mixed system;

[0078] S3.3: Drop the mixed system into 12 parts by weight of a 10% zinc nitrate hexahydrate solution using a dropper, then add it to the 5 wt% tannic acid solution, mix for 5 min, and perform freeze-drying to obtain sustained-release gel microspheres;

[0079] S4: Preparation of Modified Chitosan Derivatives

[0080] S4.1: Mix 10 parts by weight of 8-hydroxyquinoline, 11 parts by weight of concentrated hydrochloric acid, and 11 parts by weight of 37 wt% formaldehyde, then introduce hydrogen chloride gas at 28 °C, stir and react for 12 h, then perform suction filtration, washing, and drying to obtain 5-chloromethyl-8-hydroxyquinoline hydrochloride;

[0081] S4.2: Add 1.38 parts by weight of chitosan cinnamaldehyde Schiff base to 100 parts by weight of acetic acid solution with a concentration of 3%, conduct a swelling reaction for 2 h, then add 1.78 parts by weight of 5-chloromethyl-8-hydroxyquinoline hydrochloride, raise the temperature to 83 °C, react for 28 h, then add a sodium hydroxide solution with a concentration of 10% to adjust the pH to neutral, and finally conduct suction filtration, washing, and drying to obtain a modified chitosan derivative;

[0082] S5: Preparation of chlorine dioxide composite disinfectant

[0083] S5.1: Mix 2 parts by weight of lithium magnesium silicate with 30 parts by weight of deionized water evenly, place it in a water bath at 30 °C, stir, and let it stand at room temperature to obtain a lithium magnesium silicate activation solution;

[0084] S5.2: Add 2 parts by weight of the modified chitosan derivative to 10 parts by weight of acetic acid solution with a concentration of 2%, stir and mix at 300 r / min for 30 min, then add the lithium magnesium silicate activation solution and stir and mix for 12 min to obtain a coating solution;

[0085] S5.3: Spray 32 parts by weight of the coating solution onto 10 parts by weight of sustained-release gel microspheres in a sugar coating machine, and then conduct freeze-drying to obtain a chlorine dioxide composite disinfectant.

[0086] Example 3

[0087] A preparation process of a composite disinfectant containing chlorine dioxide, comprising the following steps:

[0088] S1: Preparation of carrier stabilizer

[0089] S1.1: Mix 3 parts by weight of sodium hydroxide, 0.8 parts by weight of sodium aluminate, and 32 parts by weight of deionized water, then stir at 2000 r / min and stir and mix for 20 min to obtain a mixed solution;

[0090] S1.2: Add 4.23 parts by weight of sodium silicate nonahydrate to the mixed solution, stir and mix for 6 h, then put it into a stainless steel high-pressure reactor, react at 80 °C for 14 h, then wash with deionized water until neutral, conduct vacuum drying, then react in a nitrogen atmosphere at 500 °C for 4 h, and then grind and crush to obtain a carrier stabilizer;

[0091] S2: Preparation of modified carboxymethyl chitosan

[0092] S2.1: Add 0.8 parts by weight of 3-carboxy-5-nitrobenzeneboronic acid, 0.69 parts by weight of 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, and 0.46 parts by weight of N-hydroxysuccinimide to 35 parts by weight of dimethyl sulfoxide, stir and mix at 200 r / min for 4 h to obtain an activation solution;

[0093] S2.2: Add 5 parts by weight of carboxymethyl chitosan to 420 parts by weight of deionized water, stir and mix for 20 min to obtain a carboxymethyl chitosan solution;

[0094] S2.3: Use a syringe to drop the activation solution into the carboxymethyl chitosan solution, stir at room temperature for 10 h, then add 0.1 M sodium hydroxide solution to adjust the pH to 9.2, then place it in a dialysis bag and dialyze for 3 d, changing the water every 4 h during dialysis. After dialysis is completed, perform freeze-drying to obtain modified carboxymethyl chitosan;

[0095] S3: Preparation of sustained-release gel microspheres

[0096] S3.1: Add 5 parts by weight of modified carboxymethyl chitosan to deionized water, stir and mix for 20 min to obtain a 4 wt% modified carboxymethyl chitosan solution. Add 3 parts by weight of tannic acid to phosphate buffered saline, stir and mix for 20 min to obtain a 5 wt% tannic acid solution;

[0097] S3.2: Add 3 parts by weight of carrier stabilizer to 12 parts by weight of deionized water, sonicate for 20 min to obtain a mixture, then add 8% (W / V) of the 4 wt% modified carboxymethyl chitosan solution and 20% (W / V) sodium chlorite, stir at room temperature for 2 h to obtain a mixed system;

[0098] S3.3: Drop the mixed system into 15 parts by weight of a 10% zinc nitrate hexahydrate solution using a dropper, then add it to the 5 wt% tannic acid solution, mix for 3 min, and perform freeze-drying to obtain sustained-release gel microspheres;

[0099] S4: Preparation of modified chitosan derivatives

[0100] S4.1: Mix 12 parts by weight of 8-hydroxyquinoline, 13 parts by weight of concentrated hydrochloric acid and 13 parts by weight of 37 wt% formaldehyde, then pass hydrogen chloride gas at 25 °C, stir and react for 10 h, then perform suction filtration, washing and drying to obtain 5-chloromethyl-8-hydroxyquinoline hydrochloride;

[0101] S4.2: Add 1.42 parts by weight of chitosan cinnamaldehyde Schiff base to 120 parts by weight of a 3% acetic acid solution, perform a swelling reaction for 1 h, then add 1.83 parts by weight of 5-chloromethyl-8-hydroxyquinoline hydrochloride, raise the temperature to 80 °C, react for 24 h, then add a 10% sodium hydroxide solution to adjust the pH to neutral, and finally perform suction filtration, washing and drying to obtain modified chitosan derivatives;

[0102] S5: Preparation of chlorine dioxide composite disinfectant

[0103] S5.1: Mix 3 parts by weight of lithium magnesium silicate uniformly with 38 parts by weight of deionized water, place it in a water bath at 15 °C, stir, and let it stand at room temperature to obtain an activated solution of lithium magnesium silicate;

[0104] S5.2: Add 4 parts by weight of the modified chitosan derivative to 12 parts by weight of an acetic acid solution with a concentration of 3%, stir and mix at 200 r / min for 20 min, then add the activated solution of lithium magnesium silicate and stir and mix for 10 min to obtain a coating solution;

[0105] S5.3: Spray 45 parts by weight of the coating solution onto 12 parts by weight of the sustained-release gel microspheres in a sugar coating machine, and then freeze-dry to obtain a chlorine dioxide composite disinfectant.

[0106] Comparative Example 1

[0107] Compared with Example 1, the difference in Comparative Example 1 is that Comparative Example 1 removes step S1, and replaces S3.2 with "Add an 8% (W / V) 4 wt% modified carboxymethyl chitosan solution and 20% (W / V) sodium chlorite to 10 parts by weight of deionized water, and stir at room temperature for 1 h to obtain a mixed system", and the other steps remain unchanged to prepare the chlorine dioxide composite disinfectant, denoted as Comparative Example 1.

[0108] Comparative Example 2

[0109] Compared with Example 1, the difference in Comparative Example 2 is that Comparative Example 2 removes step S2, and replaces the modified carboxymethyl chitosan in step S3.1 with carboxymethyl chitosan, and the other steps remain unchanged to prepare the chlorine dioxide composite disinfectant, denoted as Comparative Example 2.

[0110] Comparative Example 3

[0111] Compared with Example 1, the difference in Comparative Example 3 is that Comparative Example 3 replaces step S3.3 with "First mix 12 parts by weight of a 10% zinc nitrate hexahydrate solution and a 5 wt% tannic acid solution, then use a dropper to add the mixed system, mix for 3 min, and perform freeze-drying to obtain the sustained-release gel microspheres", and the other steps remain unchanged to prepare the chlorine dioxide composite disinfectant, denoted as Comparative Example 3.

[0112] Comparative Example 4

[0113] Compared with Example 1, the difference in Comparative Example 4 is that Comparative Example 4 removes steps S4 - S5, and the sustained-release gel microspheres prepared in step S3 are the chlorine dioxide composite disinfectant, denoted as Comparative Example 4.

[0114] Comparative Example 5

[0115] Compared with Example 1, the difference in Comparative Example 5 is that in Comparative Example 5, step S4 is removed, and the modified chitosan derivative in step S5.2 is replaced with chitosan cinnamaldehyde Schiff base, and the remaining steps remain unchanged to prepare the chlorine dioxide composite disinfectant, denoted as Comparative Example 5.

[0116] Comparative Example 6

[0117] Compared with Example 1, the difference in Comparative Example 6 is that in Comparative Example 6, the tannic acid solution in step S3.3 is removed, and the remaining steps remain unchanged to prepare the chlorine dioxide composite disinfectant, denoted as Comparative Example 6.

[0118] Determination of sustained-release performance:

[0119] The sustained-release performance of Examples 1-3 and Comparative Examples 1-3, 6 was measured. The chlorine dioxide composite disinfectant was prepared into a solution at a ratio of 1 g:1 L of water, placed in a spray bottle according to the habit of environmental disinfection in the normal environment, and then placed in a sealed glass instrument of 30 dm 3 . Timing was started, and a portable chlorine dioxide detector was used to measure the amount of chlorine dioxide released at room temperature. The chlorine dioxide release amount was recorded every 20 min, and the release rate was calculated based on the release amount as shown in the following formula:

[0120] Release rate (ppm / min) = (C - C0) / T;

[0121] Among them, the release rate is the sustained-release rate of chlorine dioxide (ppm / min), C is the concentration at the end of the test (ppm), C0 is the initial concentration (ppm), T is the total test time (min), and the test results are for reference Figure 1 .

[0122] According to Figure 1 's sustained-release rate curve, it can be seen that the chlorine dioxide composite disinfectant prepared by the present invention can achieve a stable and long-lasting sustained-release effect. From the data of Comparative Example 1, it can be seen that adding a carrier stabilizer during the preparation of the sustained-release gel microspheres can avoid the burst release in the initial stage of the sustained-release gel microspheres.

[0123] From the data of Comparative Example 2, it can be seen that using modified carboxymethyl chitosan to prepare the sustained-release gel microspheres can release the chlorine dioxide component smoothly and slowly because the modified carboxymethyl chitosan can improve the crosslinking effect and enhance the stability of the gel network, achieving the effect of slow release.

[0124] From the data of Comparative Example 3 and Comparative Example 6, it can be seen that when preparing the sustained-release gel microspheres, reacting with zinc nitrate hexahydrate first and then adding it to the tannic acid solution can slow down the problems of burst release of chlorine dioxide gas and unstable gas sustained-release rate.

[0125] Determination of stability:

[0126] The stability (the degradation rate of the active ingredient content ≤ 10%) of Examples 1 - 3 and Comparative Example 4 was determined according to GB / T 26366-2021 Hygienic Requirements for Chlorine Dioxide Disinfectants. The test results are shown in Table 1.

[0127] Table 1. Determination Results of the Stability of Chlorine Dioxide Composite Disinfectants

[0128]

[0129] It can be seen from the data in Table 1 that by using the coating liquid to coat the sustained-release gel microspheres, the embedding stability can be effectively improved, the sustained-release gel microspheres can be kept in a stable state, thereby improving the stability of the chlorine dioxide composite disinfectant and increasing the storage time.

[0130] The chlorine dioxide composite disinfectants prepared in Examples 1 - 3 and Comparative Examples 4 - 5 were formulated into a solution at a ratio of 1 g:1 L of water, and placed in a spray bottle according to the usual habit of environmental disinfection; then, according to item 2.2.4 of the Disinfection Technical Specification (2002 edition), the corrosiveness of the disinfectant was determined, and the determination results are shown in Table 2 for reference.

[0131] Table 2. Corrosiveness Determination of Examples 1 - 3 and Comparative Examples 4 - 5

[0132]

[0133] It can be seen from the data in Table 2 that adding modified chitosan derivatives to the coating liquid can slow down the corrosion of stainless steel metal materials by chlorine dioxide gas, and the modified chitosan derivatives can further improve the corrosion inhibition effect.

[0134] Determination of Microbial Killing Performance:

[0135] The chlorine dioxide composite disinfectants prepared in Examples 1 - 3 and Comparative Example 6 were formulated into a solution at a ratio of 1 g:1 L of water, and placed in a spray bottle according to the usual habit of environmental disinfection; according to GB / T 26366-2021 Hygienic Requirements for Chlorine Dioxide Disinfectants, the microbial killing performance was determined, and the test results are shown in Table 3:

[0136] Table 3. Determination Results of the Microbial Killing Performance of Examples 1 - 3 and Comparative Example 6

[0137]

[0138] It can be seen from Table 3 that the chlorine dioxide composite disinfectant prepared by the present invention has a good disinfection effect, and adding tannic acid solution can improve the antibacterial effect.

[0139] The above embodiments are only illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. Preparation process of a composite disinfectant containing chlorine dioxide, characterized in that, It includes the following steps: S1: Preparation of carrier stabilizer Sodium hydroxide, sodium aluminate and deionized water are mixed and then sodium silicate nonahydrate is added to react to prepare the carrier stabilizer; S2: Preparation of modified carboxymethyl chitosan 3-Carboxy-5-nitrophenylboronic acid, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, N-hydroxysuccinimide and dimethyl sulfoxide are used to modify carboxymethyl chitosan to prepare modified carboxymethyl chitosan; S3: Preparation of sustained-release gel microspheres S3.1: Add 3-5 parts by weight of modified carboxymethyl chitosan to deionized water, stir and mix for 20-30 min to obtain a 4 wt% modified carboxymethyl chitosan solution. Add 2-3 parts by weight of tannic acid to phosphate buffered saline, stir and mix for 20-30 min to obtain a 5 wt% tannic acid solution; S3.2: Add 2-3 parts by weight of carrier stabilizer to 10-12 parts by weight of deionized water, ultrasonicate for 20-30 min to obtain a mixture, then add the 4 wt% modified carboxymethyl chitosan solution and sodium chlorite, and stir at room temperature for 1-2 h to obtain a mixed system; S3.3: Drop the mixed system into 12-15 parts by weight of a 10% zinc nitrate hexahydrate solution using a dropper, and then add it to the 5 wt% tannic acid solution, mix for 3-5 min, and perform freeze-drying to obtain the sustained-release gel microspheres; S4: Preparation of modified chitosan derivative 5-Chloromethyl-8-hydroxyquinoline hydrochloride is used to modify chitosan cinnamaldehyde Schiff base to obtain the modified chitosan derivative; S5: Preparation of chlorine dioxide composite disinfectant S5.1: Mix 2-3 parts by weight of lithium magnesium silicate with 30-38 parts by weight of deionized water evenly, place it in a water bath at 15-30 °C, stir, and let it stand at room temperature to obtain a lithium magnesium silicate activation solution; S5.2: Add 2-4 parts by weight of modified chitosan derivative to 10-12 parts by weight of a 2-3% acetic acid solution, stir and mix at 200-300 r / min for 20-30 min, then add the lithium magnesium silicate activation solution, and stir and mix for 10-12 min to obtain a coating solution; S5.3: Spray 32-45 parts by weight of the coating solution onto 10-12 parts by weight of the sustained-release gel microspheres in a sugar coating machine, and then perform freeze-drying to obtain the chlorine dioxide composite disinfectant.

2. The preparation process of a composite disinfectant containing chlorine dioxide according to claim 1, characterized in that, For the preparation of the carrier stabilizer in step S1, it specifically includes the following steps: S1.1: Mix 2-3 parts by weight of sodium hydroxide, 0.5-0.8 parts by weight of sodium aluminate and 29-32 parts by weight of deionized water, then stir at 2000-3000 r / min, stir and mix for 20-30 min to obtain a mixed solution; S1.2: Add 3.81-4.23 parts by weight of sodium silicate nonahydrate to the mixed solution, stir and mix for 6-8 h, then put it into a stainless steel autoclave, react at 80-82 °C for 14-15 h, then wash with deionized water until neutral, vacuum dry, then react in a nitrogen atmosphere at 500-520 °C for 4-5 h, and then grind and pulverize to obtain the carrier stabilizer.

3. The preparation process of a composite disinfectant containing chlorine dioxide according to claim 2, characterized in that, For the preparation of the modified carboxymethyl chitosan in step S2, it specifically includes the following steps: S2.1: Add 0.6 - 0.8 parts by weight of 3 - carboxy - 5 - nitrobenzeneboronic acid, 0.52 - 0.69 parts by weight of 1 - ethyl - (3 - dimethylaminopropyl)carbodiimide hydrochloride, and 0.33 - 0.46 parts by weight of N - hydroxysuccinimide into 30 - 35 parts by weight of dimethyl sulfoxide, and stir - mix at 200 - 300 r / min for 4 - 5 h to obtain an activation solution; S2.2: Add 3 - 5 parts by weight of carboxymethyl chitosan into 400 - 420 parts by weight of deionized water, and stir - mix for 20 - 30 min to obtain a carboxymethyl chitosan solution; S2.3: Use a syringe to drip the activation solution into the carboxymethyl chitosan solution, stir at room temperature for 10 - 12 h, then add 0.1 M sodium hydroxide solution to adjust the pH to 9 - 9.2, then put it into a dialysis bag and dialyze for 3 - 4 d, changing water every 4 - 5 h during dialysis. After dialysis is completed, perform freeze - drying to obtain modified carboxymethyl chitosan.

4. The preparation process of a composite disinfectant containing chlorine dioxide according to claim 3, characterized in that, Step S4 Preparation of modified chitosan derivative, specifically including the following steps: S4.1: Mix 10 - 12 parts by weight of 8 - hydroxyquinoline, 11 - 13 parts by weight of concentrated hydrochloric acid, and 11 - 13 parts by weight of 37 wt% formaldehyde, then introduce hydrogen chloride gas at 25 - 28 °C, stir and react for 10 - 12 h, then perform suction filtration, washing, and drying to obtain 5 - chloromethyl - 8 - hydroxyquinoline hydrochloride; S4.2: Add 1.38 - 1.42 parts by weight of chitosan cinnamaldehyde Schiff base into 100 - 120 parts by weight of 3% acetic acid solution, perform a swelling reaction for 1 - 2 h, then add 1.78 - 1.83 parts by weight of 5 - chloromethyl - 8 - hydroxyquinoline hydrochloride, raise the temperature to 80 - 83 °C, react for 24 - 28 h, then add 10% sodium hydroxide solution to adjust the pH to neutral, and finally perform suction filtration, washing, and drying to obtain a modified chitosan derivative.

5. The preparation process of a composite disinfectant containing chlorine dioxide according to claim 1, characterized in that, The addition amount of the 4 wt% modified carboxymethyl chitosan solution in step S3.1 is 8 - 10% (W / V) of the mixture.

6. The preparation process of a composite disinfectant containing chlorine dioxide according to claim 1, characterized in that, The addition amount of sodium chlorite in step S3.1 is 20 - 23% (W / V) of the mixture.

7. A composite disinfectant containing chlorine dioxide, characterized in that, It is prepared by the preparation process of a composite disinfectant containing chlorine dioxide described in any one of claims 1 - 6.

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