Tirpinimo bandymas of plastic veterinary syringe

Tirpinimo bandymas of plastic veterinary syringe:

Preparation of test solution: Take the internal surface area of this product (needle tube) 600cm2 (split into pieces of 5cm long and 0.3cm wide), set

Add appropriate amount of water to the conical flask, shake and wash the small pieces, discard the water, and repeat the operation twice. After drying at 30 ～ 40 ℃, use water (70 ℃ ± 2 ℃)

After soaking in 200ml for 24 hours, take it out and let it cool to room temperature, use the same batch of test solvent to make up the original volume as the test solution, and use the same batch of water as a blank

Liquid, perform the following tests:

6.6.1 pH change

Take 20ml each of the test solution and the water blank solution, add 1.0ml of potassium chloride solution (1 → 1000) respectively, and determine according to the law ("Chinese People's

"He Guoguo Pharmacopoeia" 2015 edition two general rules 0631) measured, the difference between the two pH value should not exceed 1.0.

dial a dose syringe

6.6.2 Heavy metals

Accurately take 20ml of water for the test solution, add 2ml of acetate buffer (pH 3.5), and determine according to the law ("Veterinary Pharmacopoeia of the People's Republic of China")

The 2015 edition of the General Principles of the Second Department (0821, Act 1), containing heavy metals shall not exceed one part per million.

6.6.3 Easy oxide

Accurately take 20ml of water for the test solution, add 20ml of potassium permanganate titration solution (0.002mol / L) and 1ml of dilute sulfuric acid, and boil for 3 minutes.

Quickly cool to room temperature. Add 0.1g potassium iodide, place in the dark for 5 minutes, titrate with sodium thiosulfate titration solution (0.01mol / L), titrate

To the near end, add 5 drops of starch indicator solution and continue titration until colorless. Take another water blank solution and operate in the same way, both consume sodium thiosulfate drops

The difference of fixed solution (0.01mol / L) should not exceed 1.5ml.

6.6.4 Non-volatile matter

Accurately take 50ml each of the test solution and the blank solution, put them in an evaporating dish with constant weight, evaporate to dryness in a water bath, and dry to constant weight at 105 ℃.

The difference between the two should not exceed 12.0mg.