Mangosteen leaves contain xanthone from flavonoids substance can be used as
antioxidants. Mangosteen leaves are formulated into nanoparticles compound
which are made available into nano size through ionic gelation method. The
making of mangosteen leaves extract employs maceration method by using 50%
technical ethanol continued with evaporation until thick mangosteen leaf extract is
formed. The nanoparticle formula is made by mixing mangosteen leaf extract in
ethanol, a solution of chitosan in glacial acetic acid as a polymer, and NaTPP as a
cross-linker solution. There are 3 formulas used, namely the difference in chitosan
concentration which is 0.050; 0.075; and 0.100. Characterization using PSA was
produced in formulations 1, 2 and 3, 219.6 nm; 233.4 nm; and 329.1 nm,
respectively. The potential zeta characterization shows that formulation 1 has a
potential zeta value of 15.3 mV. The Rf value of the three samples in formula 1,
formula 2, and 3 are 0.887; 0,900; and 0,837, respectively. The results of the Rf
value on 50% ethanol extract of mangosteen leaves were 0.875 indicating that the
compounds contained in the mangosteen leaf ethanol extract and in the
preparation of nanoparticles were the same. Examination of antioxidant activity in
mangosteen leaf extract nanoparticles with DPPH free radical reduction method
showed that the three samples had a lower antioxidant effectiveness of about 50
times than quercetin as a positive control. The IC50 value in each formula
(Formula 1, 2 and 3) is 25,398 μg/ml; 37,683 μg/ml; and 33,784 μg/ml. These
results indicate that the three samples in the form of nanoparticles still have very
strong antioxidant effectiveness.