Glucosamine is a hexosamine sugar compound, naturally produced inside the body and concentrated
within the cartilage. Glucosamine supplements are among the most commonly used products to lighten
the symptoms in osteoarthritis. High dose or prolonged use of glucosamine could increase the risk of
developing diabetes. Therefore, determination of glucosamine in dossage form is needed. By its
structure, glucosamine does not have a chromophoric group so that analysis with Spectrophotometry
UV-Visible method cannot be done directly, but it needs a pre-treatment reaction. The purpose of this
research was to validate determination method of glucosamine HCl level with spectrophotometry UV-
Visible method using chloramine-T and crystal violet reagents in acidic state and determination of
glucosamine HCl level in commercial tablet. Glucosamine HCl was dissolved in aquadest and reacted
with 0.02 M chloramine-T in acidic state (HCl 2 M), the reaction was allowed for 15 minutes then
added 0.01% crystal violet to react for 5 minutes. The result of this reaction was analyzed with
Spectrophotometer UV-Visible Beckman DU 720 with maximum absorbtion wavelength at 435 nm.
This study gave linearity in range of 12-86 ?g/mL with correlation coefficient (r) of 0.9996, accuracy
with percent recovery of 98.61-101.12%; repeatability with coefficient of variance of 1.19, and
interday presicion with coefficient of variance day one, two, and three were 1.19, 1.71, and 1.14%,
respectively. Meanwhile for glucosamine HCl standard spiked method, the study gave accuracy with
percent recovery of 98.39-100.69% and presicion with coefficient of variance of 1.61%. Glucosamine
HCl level determination with spectrophotometry UV-Visible method with chloramine-T and crystal
violet reagents provide a valid result dan levels of glucosamine HCl in commercial tablet A, B, and C
were 96.11, 103.55, and 93.02%, respectively.