APPLICATION OF ISOLATED AGAROSE AS A NEW ADSORBENT IN ANALYSIS OF TARTRAZINE BY A VISIBLE-SPECTROPHOTOMETRY METHOD

Abstract

This study aims to isolate agarose from agar and use isolated agarose as an adsorbent in the analysis of tartrazine by the vis-spectrophotometry method. Isolation of agarose from agar was conducted with the mixture of propylene glycol and distilled water (19:1) as solvent at 105°C, agarose was then precipitated from solution by addition of isopropyl alcohol and the mixture allowed at a temperature of 10°C. The adsorption and desorption capacity experiment of agarose to tartrazine was carried out with variations in pH, contact time and concentration of tartrazine. Adsorbed or released tartrazine by agarose was quantified by spectrophotometry method at a wavelength of 427 nm. The adsorption process of agarose to tartrazine was found optimal at the appropriate experimental condition, namely at acidic milieu (pH 4) and contact time for 60 minutes, meanwhile the desorption process of isolated agarose was optimal at basic condition (pH 9) and contact time for 60 minutes. Adsorption and desorption process of 0.25 g of agarose was optimal in an experiment used 25 ml of 5.6 $\mu$g/ml tartrazine solution as adsorbate, which gave adsorption and desorption capacity of 0.1108 (± 0.0014) and 0.1083
± (0.0014) mg/g, respectively. It could be concluded that agarose can be used and developed as a new adsorbent in the analysis of tartrazine.