Study On The Nonenzymatic Browning, Surface Modification And Hygroscopic Property Of Glucosamine Sulfate

Osteoarthritis, a degenerative joint disease, cause a lot of distress to patients suffering from such a disease, this disease is mostly prevalent in older people, become major social probloms that threaten the well-being of the senior citizen seriously. The standard therapy for the treatment of osteoarthritis mostly includes the use of corticosteroids, non-steroidal anti-inflammatory drugs （NSAID’s） e.g. aspirin, ibuprofen etc. However, all these drugs are associated with one or more side effects and adverse reaction. A great deal of scientific research proved that glucosamine sulfate represents a new generation of drug, discovered that it can slow down the progression of osteoarthritis and also alleviate the pain associated with this disease,and also cause fewer side effects, so glucosamine sulfate shall become the first the ideal drug to treat osteoarthritis that can prevent the degeneration of the joint .Although highly effective, glucosamine sulfate has several drawbacks as a pharmaceutical compound. Solid glucosamine sulfate is highly hygroscopic and its amino group oxidizes readily, nonenzymatic browning reaction happens easily.These unfavourable properties give rise to difficulties and limitations in the practical use of glucosamine sulfate. Taking into account this problem, In present thesis,the effect of different sorts of assistant ingredients on characteristics of glucosamine sulfate was studied; then studied the hygroscopic property at different temperatures, and the effect of moisture content on stability was also researched; to further discuss the readily oxidizable problem of glucosamine sulfate, in this studies, the influence of temperature , pH value and other factors on nonenzymatic browning index were discussed ,and it’s also covered the inhibitor of nonenzymatic browning reaction of glucosamine sulfate.The studies in this thesis are summarized as follows:1. High-molecular compound such as cyclodextrin, gelation and coplyvidone were applied respectively to modificate the surface of glucosamine sulfate using spray dring technique, compared the properties between the blank and samples through surface modification, the result indicated that the application of surface modification technique could increase the powder yield of spray dry and glass transition temperature of glucosamine sulfate, could also improve the stability and fluidity of glucosamine sulfate powder.2. Selecting gravimetric method studied the hygroscopic character of glucosamine sulfate, found that at 5℃, along with water activity raising, the samples could adsorb much water, but at 25 and 30℃, when water activity exceeded 0.43, samples agglomerated, browned and lose their adsorbed water; The experimental values were regressed using the BET model, found that the regression coefficient all exceeded 0.96, at 5℃,25℃and 30℃,using BET formula got the monolayer moisture content, were 4.8633、5.3742、5.5740 g/100g respectively. With the increasing of moisture content, the store stability of glucosamine sulfate decreased and the nonenzymatic browning index rose gradually.3. Content of 5-hydroxymethyfurfural,nonenzymatic browning index increased and content of glucosamine sulfate, pH value decreased with temperature rose and time extension, during heating at high temperatures （60,70,75,80） for 10h, nonenzymatic browning reaction of glucoamine sulfate was successfully adjusted to zero order kinetic model, calculated the activation energy used Arrhenius equation, were 85.127kJ/mol,136.973 kJ/mol and 77.145 kJ/mol for the change of nonenzymatic browning index, content of 5-hydroxymethyfurfural and content of glucosamine respectively. Raising pH value and environment humidity could aggravate the nonenzymatic browning reaction of glucosamine sulfate. Experiments showed that all citric acid, tartaric acid, malic acid, NaHSO₃ ,Ca²⁺ ,Sn²⁺and Al³⁺ could hold back the nonenzymatic browning of glucosamine sulfate, but ascorbic acid could not do that.