Compound topicamide eye drops and preparation method thereof

Abstract

The invention relates to a compound tropicamide eye drop and a preparation method thereof, the compound tropicamide eye drop is composed of tropicamide, phenylephrine hydrochloride, boric acid, sorbitol, aminocaproic acid, a pH regulator and water for injection, more auxiliary materials such as an antioxidant are not needed, and in addition, the stability of the obtained compound tropicamide eye drop is also remarkably improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of medicine, and particularly relates to a compound tropicamide eye drops and a preparation method thereof. Background Art

[0002] Compound tropicamide eye drops are very commonly used drugs in ophthalmology and can be used for the treatment and examination of various diseases. This drug belongs to cycloplegic agents and can be used for mydriatic examination and cycloplegic agents. The drug is a short-acting mydriatic drug, and the duration of the drug action is usually 6-8 hours. During the drug action period, symptoms such as blurred vision and photophobia may occur. The symptoms will gradually disappear after the pupil returns to normal. The active ingredients of compound tropicamide eye drops are tropicamide and phenylephrine hydrochloride. Tropicamide is an organic compound with the chemical formula C 17 H 20 N2O2, mainly used as a mydriatic drug. Tropicamide is slightly soluble in water, and there are certain difficulties in the process of preparing eye drops. Phenylephrine hydrochloride is an organic compound with the chemical formula C9H 14 ClNO2, is an α-adrenergic receptor agonist, used to prevent and treat hypotension caused by spinal anesthesia, general anesthesia, application of chlorpromazine, etc., and also used for supraventricular tachycardia and mydriatic examination. The mydriatic effects mainly include dilating the pupil, improving the diagnostic accuracy, removing pseudomyopia, relaxing the eye accommodation, and assisting in the treatment of eye diseases. The significance mainly includes promoting fundus examination, improving the accuracy of optometry, protecting children's vision, assisting in surgical treatment, and promoting eye health. Therefore, compound tropicamide eye drops have extremely high significance in clinical practice. It is of positive significance to study a compound tropicamide eye drop with a simple preparation process and high stability. Summary of the Invention

[0003] In view of the above technical problems, it is of positive significance to study a compound tropicamide eye drop with a simple preparation process and high stability. The inventor of the present invention obtained compound tropicamide eye drops during a long-term large number of studies on tropicamide and phenylephrine hydrochloride. This eye drop can greatly reduce the amount of excipients while having extremely high quality stability, increasing the safety of medication and the convenience of production, and is significantly superior to the prior art.

[0004] The solution adopted by the present invention to solve the above technical problems is as follows:

[0005] Compound tropicamide eye drops are composed of tropicamide, phenylephrine hydrochloride, boric acid, sorbitol, aminocaproic acid, pH regulator, and injection water.

[0006] Preferably, the mass concentration of boric acid in the eye drops is 1.0-1.2%, the mass concentration of sorbitol is 0.6-0.8%, and the amount concentration of aminocaproic acid is 0.12-0.18%.

[0007] Preferably, the mass concentration of boric acid in the eye drops is 1.2%, the mass concentration of sorbitol is 0.7%, and the mass concentration of aminocaproic acid is 0.16%.

[0008] Preferably, the mass concentration of tropicamide in the eye drops is 0.5%, the mass concentration of phenylephrine hydrochloride is 0.5%, and the specification is: 0.5% (0.4 ml: tropicamide 2 mg and phenylephrine hydrochloride 2 mg).

[0009] Preferably, the pH regulator is hydrochloric acid or sodium hydroxide.

[0010] The present invention also provides a preparation method of the above compound tropicamide eye drops, which includes the following steps:

[0011] (1) Add boric acid and sorbitol to 40% of the total amount of injection water in sequence and stir to dissolve, then add tropicamide and stir to dissolve to obtain the first solution;

[0012] (2) Add aminocaproic acid to 20% of the total amount of injection water and stir to dissolve to obtain the second solution;

[0013] (3) Add the second solution to the first solution, stir evenly, add phenylephrine hydrochloride to it, stir until completely dissolved, add injection water to 90% of the total amount, adjust the pH value to 6.5 - 6.8 with a pH regulator, and continue to add injection water to the total amount under stirring;

[0014] (4) Filter and sterilize with a 0.22 μm filter membrane, and fill into eye drop bottles according to the specification to obtain compound tropicamide eye drops.

[0015] The present invention uses boric acid, sorbitol, and aminocaproic acid in specific proportions as excipients for compound tropicamide eye drops, which has an unexpected technical effect on improving the stability of tropicamide and phenylephrine hydrochloride, and there is no need to use other excipients such as antioxidants. Specific Embodiments

[0016] For a better understanding of the present invention, the following embodiments are further descriptions of the present invention, but the content of the present invention is not limited to the following embodiments.

[0017] Example 1 Preparation of Compound Tropicamide Eye Drops

[0018] (1) Add 12 g of boric acid and 7 g of sorbitol to 400 ml of injection water in sequence and stir to dissolve, then add 5 g of tropicamide and stir to dissolve to obtain the first solution;

[0019] (2) Add 1.6 g of aminocaproic acid to 200 ml of injection water and stir to dissolve to obtain the second solution;

[0020] (3) Add the second liquid to the first liquid, stir evenly, add 5 g of phenylephrine hydrochloride thereto, stir until completely dissolved, add water for injection to 900 ml, adjust the pH value to 6.7 with hydrochloric acid or sodium hydroxide, and continue to add water for injection to a total volume of 1000 ml while stirring;

[0021] (4) Filter and sterilize with a 0.22 μm filter membrane, and fill into eye drop bottles according to specifications to obtain compound tropicamide eye drops.

[0022] Example 2 Preparation of compound tropicamide eye drops

[0023] (1) Add 10 g of boric acid and 6 g of sorbitol to 400 ml of water for injection in sequence, stir to dissolve, and then add 5 g of tropicamide and stir to dissolve to obtain the first liquid;

[0024] (2) Add 1.8 g of aminocaproic acid to 200 ml of water for injection and stir to dissolve to obtain the second liquid;

[0025] (3) Add the second liquid to the first liquid, stir evenly, add 5 g of phenylephrine hydrochloride thereto, stir until completely dissolved, add water for injection to 900 ml, adjust the pH value to 6.5 with hydrochloric acid or sodium hydroxide, and continue to add water for injection to a total volume of 1000 ml while stirring;

[0026] (4) Filter and sterilize with a 0.22 μm filter membrane, and fill into eye drop bottles according to specifications to obtain compound tropicamide eye drops.

[0027] Example 3 Preparation of compound tropicamide eye drops

[0028] (1) Add 11 g of boric acid and 8 g of sorbitol to 400 ml of water for injection in sequence, stir to dissolve, and then add 5 g of tropicamide and stir to dissolve to obtain the first liquid;

[0029] (2) Add 1.2 g of aminocaproic acid to 200 ml of water for injection and stir to dissolve to obtain the second liquid;

[0030] (3) Add the second liquid to the first liquid, stir evenly, add 5 g of phenylephrine hydrochloride thereto, stir until completely dissolved, add water for injection to 900 ml, adjust the pH value to 6.8 with hydrochloric acid or sodium hydroxide, and continue to add water for injection to a total volume of 1000 ml while stirring;

[0031] (4) Filter and sterilize with a 0.22 μm filter membrane, and fill into eye drop bottles according to specifications to obtain compound tropicamide eye drops.

[0032] Example 4 Preparation of compound tropicamide eye drops

[0033] (1) Add 10 g of boric acid and 8 g of sorbitol to 400 ml of water for injection in sequence, stir to dissolve, then add 5 g of tropicamide and stir to dissolve to obtain the first solution;

[0034] (2) Add 1.8 g of aminocaproic acid to 200 ml of water for injection, stir to dissolve to obtain the second solution;

[0035] (3) Add the second solution to the first solution, stir evenly, add 5 g of phenylephrine hydrochloride thereto, stir until completely dissolved, add water for injection to 900 ml, adjust the pH value to 6.5 with hydrochloric acid or sodium hydroxide, and continue to add water for injection to a total volume of 1000 ml under stirring;

[0036] (4) Filter and sterilize with a 0.22 μm filter membrane, fill into eye drops bottles according to specifications, and the compound tropicamide eye drops are obtained.

[0037] Example 5 Preparation of compound tropicamide eye drops

[0038] (1) Add 12 g of boric acid and 6 g of sorbitol to 400 ml of water for injection in sequence, stir to dissolve, then add 5 g of tropicamide and stir to dissolve to obtain the first solution;

[0039] (2) Add 1.2 g of aminocaproic acid to 200 ml of water for injection, stir to dissolve to obtain the second solution;

[0040] (3) Add the second solution to the first solution, stir evenly, add 5 g of phenylephrine hydrochloride thereto, stir until completely dissolved, add water for injection to 900 ml, adjust the pH value to 6.7 with hydrochloric acid or sodium hydroxide, and continue to add water for injection to a total volume of 1000 ml under stirring;

[0041] (4) Filter and sterilize with a 0.22 μm filter membrane, fill into eye drops bottles according to specifications, and the compound tropicamide eye drops are obtained.

[0042] Example 6 Preparation of compound tropicamide eye drops

[0043] (1) Add 12 g of boric acid and 7 g of sorbitol to 400 ml of water for injection in sequence, stir to dissolve, then add 5 g of tropicamide and stir to dissolve to obtain the first solution;

[0044] (2) Add 1.2 g of aminocaproic acid to 200 ml of water for injection, stir to dissolve to obtain the second solution;

[0045] (3) Add the second solution to the first solution, stir evenly, add 5 g of phenylephrine hydrochloride thereto, stir until completely dissolved, add water for injection to 900 ml, adjust the pH value to 6.5 with hydrochloric acid or sodium hydroxide, and continue to add water for injection to a total volume of 1000 ml under stirring;

[0046] (4) Sterilize by filtration through a 0.22 μm filter membrane and fill into eye drop bottles according to specifications to obtain compound tropicamide eye drops.

[0047] Example 7 Preparation of Compound Tropicamide Eye Drops

[0048] (1) Add 10 g of boric acid and 7 g of sorbitol successively to 400 ml of water for injection, stir to dissolve, then add 5 g of tropicamide and stir to dissolve to obtain the first solution.

[0049] (2) Add 1.6 g of aminocaproic acid to 200 ml of water for injection, stir to dissolve to obtain the second solution.

[0050] (3) Add the second solution to the first solution, stir evenly, add 5 g of adrenaline bitartrate to it, stir until completely dissolved, add water for injection to 900 ml, adjust the pH value to 6.8 with hydrochloric acid or sodium hydroxide, and continue to add water for injection to a total volume of 1000 ml while stirring.

[0051] (4) Sterilize by filtration through a 0.22 μm filter membrane and fill into eye drop bottles according to specifications to obtain compound tropicamide eye drops.

[0052] Example 8 Preparation of Compound Tropicamide Eye Drops

[0053] (1) Add 12 g of boric acid and 6 g of sorbitol successively to 400 ml of water for injection, stir to dissolve, then add 5 g of tropicamide and stir to dissolve to obtain the first solution.

[0054] (2) Add 1.8 g of aminocaproic acid to 200 ml of water for injection, stir to dissolve to obtain the second solution.

[0055] (3) Add the second solution to the first solution, stir evenly, add 5 g of adrenaline bitartrate to it, stir until completely dissolved, add water for injection to 900 ml, adjust the pH value to 6.7 with hydrochloric acid or sodium hydroxide, and continue to add water for injection to a total volume of 1000 ml while stirring.

[0056] (4) Sterilize by filtration through a 0.22 μm filter membrane and fill into eye drop bottles according to specifications to obtain compound tropicamide eye drops.

[0057] Comparative Example 1 Preparation of Compound Tropicamide Eye Drops

[0058] (1) Add 9 g of boric acid and 7 g of sorbitol successively to 400 ml of water for injection, stir to dissolve, then add 5 g of tropicamide and stir to dissolve to obtain the first solution.

[0059] (2) Add 1.6 g of aminocaproic acid to 200 ml of water for injection, stir to dissolve to obtain the second solution.

[0060] (3) Add the second liquid to the first liquid, stir evenly, add 5 g of phenylephrine hydrochloride thereto, stir until completely dissolved, add water for injection to 900 ml, adjust the pH value to 6.7 with hydrochloric acid or sodium hydroxide, and continue to add water for injection to a total volume of 1000 ml while stirring;

[0061] (4) Filter and sterilize with a 0.22 μm filter membrane, and fill into eye drops bottles according to the specifications to obtain compound tropicamide eye drops.

[0062] Comparative Example 2 Preparation of compound tropicamide eye drops

[0063] (1) Add 12 g of boric acid and 7 g of sorbitol to 400 ml of water for injection in sequence, stir to dissolve, and then add 5 g of tropicamide and stir to dissolve to obtain the first liquid;

[0064] (2) Add 1.9 g of aminocaproic acid to 200 ml of water for injection, stir to dissolve to obtain the second liquid;

[0065] (3) Add the second liquid to the first liquid, stir evenly, add 5 g of phenylephrine hydrochloride thereto, stir until completely dissolved, add water for injection to 900 ml, adjust the pH value to 6.7 with hydrochloric acid or sodium hydroxide, and continue to add water for injection to a total volume of 1000 ml while stirring;

[0066] (4) Filter and sterilize with a 0.22 μm filter membrane, and fill into eye drops bottles according to the specifications to obtain compound tropicamide eye drops.

[0067] Comparative Example 3 Preparation of compound tropicamide eye drops

[0068] (1) Add 12 g of boric acid and 5 g of sorbitol to 400 ml of water for injection in sequence, stir to dissolve, and then add 5 g of tropicamide and stir to dissolve to obtain the first liquid;

[0069] (2) Add 1.6 g of aminocaproic acid to 200 ml of water for injection, stir to dissolve to obtain the second liquid;

[0070] (3) Add the second liquid to the first liquid, stir evenly, add 5 g of phenylephrine hydrochloride thereto, stir until completely dissolved, add water for injection to 900 ml, adjust the pH value to 6.8 with hydrochloric acid or sodium hydroxide, and continue to add water for injection to a total volume of 1000 ml while stirring;

[0071] (4) Filter and sterilize with a 0.22 μm filter membrane, and fill into eye drops bottles according to the specifications to obtain compound tropicamide eye drops.

[0072] Comparative Example 4 Preparation of compound tropicamide eye drops

[0073] (1) Add 13 g of boric acid and 9 g of sorbitol to 400 ml of water for injection in sequence, stir to dissolve, then add 5 g of tropicamide and stir to dissolve to obtain the first solution;

[0074] (2) Add 1.9 g of aminocaproic acid to 200 ml of water for injection, stir to dissolve to obtain the second solution;

[0075] (3) Add the second solution to the first solution, stir evenly, add 5 g of phenylephrine hydrochloride thereto, stir until completely dissolved, add water for injection to 900 ml, adjust the pH value to 6.7 with hydrochloric acid or sodium hydroxide, and continue to add water for injection to a total volume of 1000 ml while stirring;

[0076] (4) Filter and sterilize with a 0.22 μm filter membrane, and fill into eye drop bottles according to specifications to obtain compound tropicamide eye drops.

[0077] Comparative Example 5 Preparation of Compound Tropicamide Eye Drops

[0078] (1) Add 9 g of boric acid and 5 g of sorbitol to 400 ml of water for injection in sequence, stir to dissolve, then add 5 g of tropicamide and stir to dissolve to obtain the first solution;

[0079] (2) Add 1.1 g of aminocaproic acid to 200 ml of water for injection, stir to dissolve to obtain the second solution;

[0080] (3) Add the second solution to the first solution, stir evenly, add 5 g of phenylephrine hydrochloride thereto, stir until completely dissolved, add water for injection to 900 ml, adjust the pH value to 6.5 with hydrochloric acid or sodium hydroxide, and continue to add water for injection to a total volume of 1000 ml while stirring;

[0081] (4) Filter and sterilize with a 0.22 μm filter membrane, and fill into eye drop bottles according to specifications to obtain compound tropicamide eye drops.

[0082] Comparative Example 6 Preparation of Compound Tropicamide Eye Drops

[0083] (1) Add 13 g of boric acid and 5 g of sorbitol to 400 ml of water for injection in sequence, stir to dissolve, then add 5 g of tropicamide and stir to dissolve to obtain the first solution;

[0084] (2) Add 1.8 g of aminocaproic acid to 200 ml of water for injection, stir to dissolve to obtain the second solution;

[0085] (3) Add the second solution to the first solution, stir evenly, add 5 g of phenylephrine hydrochloride thereto, stir until completely dissolved, add water for injection to 900 ml, adjust the pH value to 6.8 with hydrochloric acid or sodium hydroxide, and continue to add water for injection to a total volume of 1000 ml while stirring;

[0086] (4) Sterilize by filtration through a 0.22 μm filter membrane and fill into eye drop bottles according to the specifications to obtain compound tropicamide eye drops.

[0087] Comparative Example 7 Preparation of compound tropicamide eye drops

[0088] (1) Add 12 g of boric acid and 9 g of sorbitol to 400 ml of water for injection in sequence, stir to dissolve, then add 5 g of tropicamide and stir to dissolve to obtain the first solution;

[0089] (2) Add 1.9 g of aminocaproic acid to 200 ml of water for injection and stir to dissolve to obtain the second solution;

[0090] (3) Add the second solution to the first solution, stir evenly, add 5 g of adrenaline hydrochloride to it, stir until completely dissolved, add water for injection to 900 ml, adjust the pH value to 6.7 with hydrochloric acid or sodium hydroxide, and continue to add water for injection to a total volume of 1000 ml while stirring;

[0091] (4) Sterilize by filtration through a 0.22 μm filter membrane and fill into eye drop bottles according to the specifications to obtain compound tropicamide eye drops.

[0092] Comparative Example 8 Preparation of compound tropicamide eye drops

[0093] (1) Add 12 g of boric acid and 9 g of sorbitol to 400 ml of water for injection in sequence, stir to dissolve, then add 5 g of tropicamide and stir to dissolve to obtain the first solution;

[0094] (2) Add 1.1 g of aminocaproic acid to 200 ml of water for injection and stir to dissolve to obtain the second solution;

[0095] (3) Add the second solution to the first solution, stir evenly, add 5 g of adrenaline hydrochloride to it, stir until completely dissolved, add water for injection to 900 ml, adjust the pH value to 6.7 with hydrochloric acid or sodium hydroxide, and continue to add water for injection to a total volume of 1000 ml while stirring;

[0096] (4) Sterilize by filtration through a 0.22 μm filter membrane and fill into eye drop bottles according to the specifications to obtain compound tropicamide eye drops.

[0097] Comparative Example 9 Preparation of compound tropicamide eye drops

[0098] (1) Add 12 g of boric acid and 7 g of sorbitol to 300 ml of water for injection in sequence, stir to dissolve, then add 5 g of tropicamide and stir to dissolve to obtain the first solution;

[0099] (2) Add 1.6 g of aminocaproic acid to 200 ml of water for injection and stir to dissolve to obtain the second solution;

[0100] (3) Add the second liquid to the first liquid, stir evenly, add 5 g of phenylephrine hydrochloride thereto, stir until completely dissolved, add water for injection to 900 ml, adjust the pH value to 6.7 with hydrochloric acid or sodium hydroxide, and continue to add water for injection to a total volume of 1000 ml while stirring;

[0101] (4) Filter and sterilize with a 0.22 μm filter membrane, and fill into eye drops bottles according to the specifications to obtain compound tropicamide eye drops.

[0102] Among them, at step (1), tropicamide cannot be completely dissolved.

[0103] Comparative Example 10 Preparation of Compound Tropicamide Eye Drops

[0104] (1) Add 12 g of boric acid to 400 ml of water for injection, stir to dissolve, then add 5 g of tropicamide and stir to dissolve to obtain the first liquid;

[0105] (2) Add 1.6 g of aminocaproic acid and 7 g of sorbitol to 200 ml of water for injection, stir to dissolve to obtain the second liquid;

[0106] (3) Add the second liquid to the first liquid, stir evenly, add 5 g of phenylephrine hydrochloride thereto, stir until completely dissolved, add water for injection to 900 ml, adjust the pH value to 6.7 with hydrochloric acid or sodium hydroxide, and continue to add water for injection to a total volume of 1000 ml while stirring;

[0107] (4) Filter and sterilize with a 0.22 μm filter membrane, and fill into eye drops bottles according to the specifications to obtain compound tropicamide eye drops.

[0108] Among them, at step (1), tropicamide cannot be completely dissolved.

[0109] Comparative Example 11 Preparation of Compound Tropicamide Eye Drops

[0110] (1) Add 12 g of boric acid, 7 g of sorbitol, and 1.6 g of aminocaproic acid to 400 ml of water for injection in sequence, stir to dissolve, then add 5 g of tropicamide and stir to dissolve to obtain the first liquid;

[0111] (2) Add 5 g of phenylephrine hydrochloride thereto, stir until completely dissolved, add water for injection to 900 ml, adjust the pH value to 6.7 with hydrochloric acid or sodium hydroxide, and continue to add water for injection to a total volume of 1000 ml while stirring;

[0112] (3) Filter and sterilize with a 0.22 μm filter membrane, and fill into eye drops bottles according to the specifications to obtain compound tropicamide eye drops.

[0113] Among them, at step (1), tropicamide cannot be completely dissolved.

[0114] The present invention also provides the following test and comparison results:

[0115] Samples 1-8: Compound tropicamide eye drops prepared in Examples 1-8 of the present invention

[0116] Samples 9-16: Compound tropicamide eye drops prepared in Comparative Examples 1-8 of the present invention

[0117] Sample 17: Commercially available compound tropicamide eye drops

[0118] Samples 1-17 were subjected to long-term stability investigation (25°C ± 2°C, RH 60% ± 5%), stored in the dark, and sampled and tested at 0, 3, and 6 months. The results are shown in Table 1.

[0119] Table 1 Long-term test results of compound tropicamide eye drops

[0120]

[0121] It can be seen from the results in Table 1 that using boric acid, aminocaproic acid, and sorbitol as excipients for compound tropicamide eye drops can significantly improve the stability of compound tropicamide eye drops, achieving unexpected technical effects. The effects are better within the range where the mass concentration of boric acid is 1.0-1.2%, the mass concentration of sorbitol is 0.6-0.8%, and the amount concentration of aminocaproic acid is 0.12-0.18%. In particular, when the mass concentration of boric acid is 1.2%, the mass concentration of sorbitol is 0.7%, and the mass concentration of aminocaproic acid is 0.16%, the effect is the best. Even a small change in the dosages of boric acid, sorbitol, and aminocaproic acid will significantly change the technical effects. In the case of changing the dissolution process and steps of tropicamide, it will cause insufficient dissolution of tropicamide.

[0122] The above is the preferred embodiment of the present invention. Of course, the scope of the rights of the present invention cannot be limited thereby. It should be pointed out that for those of ordinary skill in the art in this technical field, without departing from the principle of the present invention, several improvements and modifications can be made, and these improvements and modifications are also regarded as the protection scope of the present invention.

Claims

1. A compound tropicamide eye drop, characterized in that, It consists of tropicamide, phenylephrine hydrochloride, boric acid, sorbitol, aminocaproic acid, pH regulator, and water for injection.

2. The tropicamide and phenylephrine hydrochloride eye drops according to claim 1, wherein The mass concentration of the boric acid is 1.0 - 1.2%, the mass concentration of the sorbitol is 0.6 - 0.8%, and the amount concentration of the aminocaproic acid is 0.12 - 0.18%.

3. The tropicamide and phenylephrine hydrochloride eye drops according to claim 2, characterized in that, The mass concentration of the boric acid is 1.2%, the mass concentration of the sorbitol is 0.7%, and the mass concentration of the aminocaproic acid is 0.16%.

4. The tropicamide and phenylephrine hydrochloride compound eye drops according to claim 1, characterized in that, The mass concentration of the tropicamide is 0.5%, and the mass concentration of the phenylephrine hydrochloride is 0.5%.

5. The tropicamide and phenylephrine hydrochloride eye drops according to claim 1, wherein The specification of the eye drops is: 0.5%, 0.4 ml: tropicamide 2 mg and phenylephrine hydrochloride 2 mg.

6. The tropicamide and phenylephrine hydrochloride eye drops according to claim 1, characterized in that, The pH regulator is hydrochloric acid or sodium hydroxide.

7. A method for preparing the compound tropicamide eye drops according to any one of claims 1 to 6, characterized in that, It includes the following steps: (1) Add boric acid and sorbitol successively to 40% of the total amount of water for injection and stir to dissolve, then add tropicamide and stir to dissolve to obtain the first solution; (2) Add aminocaproic acid to 20% of the total amount of water for injection and stir to dissolve to obtain the second solution; (3) Add the second solution to the first solution, stir evenly, add phenylephrine hydrochloride to it, stir until completely dissolved, add water for injection to 90% of the total amount, adjust the pH value to 6.5 - 6.8 with the pH regulator, and continue to add water for injection to the total amount while stirring; (4) Filter and sterilize with a 0.22 μm filter membrane, and fill it into eye drop bottles according to the specification to obtain compound tropicamide eye drops.

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