Glucosamine (2-amino-2-deoxy-d-glucose, referred to as GA) is closely related to the human body and widely exists in the human body. It can reduce the production of nitric oxide, prostaglandin E, etc. in plasma and inhibit the aggregation of platelets, but it exists in binding type without free type, mainly in three ways: glucosamine hydrochloride, glucosamine sulfate and N-acetylglucosamine.

Glucosamine is the raw material of joint synovial fluid, cartilage matrix and other organs and tissues. It has the effects of anti-inflammatory, protection and nutrition of joints and cartilage. It has been used as a health food in people, and can also be used in food, cosmetics and feed additives. It is widely used. Therefore, it is necessary to establish the detection method of glucosamine content and control the quality of such drugs and health food. The reported methods for the determination of glucosamine include titration analysis, colorimetry and high performance liquid chromatography (HPLC). The content of glucosamine was determined by reverse phase high performance liquid chromatography (RP-HPLC) after derivatization reaction by adding fluorene methoxycarbonylsuccinimide (Fmoc-OSU) to glucosamine solution. The method is simple and the result is accurate and reliable

Glucosamine hydrochloride has two natural isomers. When it is just dissolved in water, its specific rotation value is the highest. With the extension of time, its specific rotation value decreases rapidly. After about 2 hours, the specific rotation tends to be stable, and the stable glucosamine hydrochloride saline solution is an equilibrium mixture of type A and type B. After derivatization of glucosamine aqueous solution, there are two peaks in the chromatogram. After scanning by diode array detector, it is found that the two peaks have the same spectrogram, so it is considered that these two peaks are two isomer peaks of glucosamine. Therefore, this study is based on the total peak area of the two peaks for quantitative analysis.

The content determination methods of glucosamine hydrochloride and other salts are included in the 27th, 28th and 29th editions of the United States Pharmacopoeia, which adopts the direct determination method of HPLC. It is detected at the wavelength of 195nm, and there is only one chromatographic peak. The study found that this method has great defects, first of all, the precision is poor, the solution is unstable, and when using glucosamine hydrochloride as the reference substance for the determination of glucosamine sulfate, the result is obviously high. Glucosamine itself has no UV absorption, and the measurement interference is relatively large at the end wavelength of 195 nm. In this study, the derivative method is used for the determination, and the derivative is detected at 265 nm. Whether it is the content determination of glucosamine hydrochloride, glucosamine sulfate API or its preparation, the test solution is relatively stable within 24 hours, with good precision, high accuracy and ideal results