1. Preface

Glucose is the most widely distributed and important monosaccharide in nature. Pure glucose is a colorless crystal, readily soluble in water, slightly soluble in ethanol, and insoluble in ether. It holds an important position in the field of biology, serving as the energy source for living cells and an intermediate product of metabolism, that is, the main energy supply substance for organisms. It is widely used in both the confectionery manufacturing industry and the pharmaceutical field. According to the provisions of GB/T 20880-2018 for edible glucose, within the range of 52.0-53.5, the specific rotation can be detected quickly and accurately by using the Shanghai Jiahang fully automatic polarimeter.

2 Instruments and reagents

2.1 Instruments

Digipol-P610 fully automatic polarimeter and analytical balance

2.2 Reagents

Glucose, ultrapure water, ammonia water (2+3)

3 Experimental Methods

3.1 Sample Preparation

Weigh 10,000 g of the glucose sample into a 100mL volumetric flask, add an appropriate amount of distilled water to dissolve it, then add 0.2mL of the previously prepared ammonia water solution and make up to the mark. Let it stand for 10 minutes.

3.2 Testing

After the blank solution of the instrument is zeroed, shake the liquid sample well. Use a pipette to draw the sample solution into the polarimetric tube. Observe the left and right sides of the polarimetric tube to ensure there are no bubbles. Place it in the sample chamber, set the appropriate test parameters of the instrument, click the test button, record the result, and each time

Place the sample once and repeat the measurement three times. Each sample is placed three times for measurement and the average value is taken.

4 Results and Discussion

4.1 Experimental Results

4.2 Discussion

The Digipol-P610 fully automatic polarimeter is easy to operate, suitable for the determination of glucose specific rotation, and has a high accuracy rate of automatic temperature control and good repeatability, which improves the working efficiency.

References

[1] GB/T 20880-2018 Edible Glucose [S].

Precautions

During the sample loading process, ensure there are no bubbles.