Healthy urine sample

(2) The principle of this experiment is that the soluble reducing sugar contained in the urine of diabetic patients can react with Fehling reagent to produce brick-red precipitate. So when taking reagents, although there are three kinds of reagents, we can only take Feyning reagent, take 2mL of Feyning reagents A and B successively with a measuring cylinder, and shake them well in No.3 test tube.

(3) Inject 2mL of evenly mixed ignition reagent in No.3 test tube into No.1 test tube 1; Inject the remaining 2mL of ignition reagent into No.2 test tube and shake evenly.

(4) Note that 1 and No.2 test tubes have the same amount of solution, and it is expected that one of the two test tubes will have brick red precipitation after being heated by water insulation. According to the serial number of the test tube that produces brick red precipitate, it can be inferred that the corresponding urine sample is the urine sample of diabetic patients, and the other bottle should be the urine sample of healthy people because it does not produce brick red precipitate.

So the answer is:

(2) Reagent taking: measure 2mL of solution A and solution B of Linfei reagent with a measuring cylinder, inject them into the No.3 test tube, and shake well.

(3) Mixing of sample and reagent: simple dosage: measure 2mL of uniformly mixed burning reagent from No.3 test tube, inject it into No.1 test tube 1, and oscillate; Inject the remaining 2mL of Feyning reagent in No.3 test tube into No.2 test tube, and shake well; (4) 【 Expected experimental result 】: Only 1 test tube and No.2 test tube produced brick red precipitate, while the other tube did not.

[Result Analysis]: The urine sample corresponding to the brick red test tube is the urine sample of diabetic patients, and the other bottle is the urine sample of healthy people. It is proved that there is soluble reducing sugar-urine sugar in urine samples of diabetic patients, which can be detected by Linfei reagent.