Stationary phase performance based on calcium oxide/silica gel on thin-layer chromatography for xanthone derivative compounds

Composite CaO/SiO2 as a stationary phase material in the chromatography system was carried out as an innovation in overcoming the weaknesses of SiO2. Testing of CaO/SiO2 material as a stationary phase was carried out on thin-layer chromatography (TLC). CaO/SiO2 material was fabricated using the casting method with methanol: water (3:1). CaO/SiO2 material was tested for its performance in elucidating α-mangosteen samples. Characterization of CaO/SiO2 material was carried out using FT-IR and XRD instruments. The FT-IR spectra of CaO/SiO2 composite shows the existence of each component of the functional group of CaO and SiO2. This is indicated by the presence of a peak of 1102 cm−1 which is the vibration of the siloxane group (Si-O-Si), 1445 cm−1, and 875 cm−1 which is an attribute of ionic vibration of the CaO material, where each of these peaks is visible and do not affect each other in all variations of the composition. The X-ray diffractogram shows that the CaO/SiO2 material has a semi-crystalline form which is characterized by a crystalline percentage value of 38.90% and has an average crystal size of 234.24. The α-mangosteen compounds have varied functional groups. The results of the performance test of CaO/SiO2 as a stationary phase showed that the minimum and maximum composition variation to be capable of elucidating α-mangosteen compounds were 10% and 60% CaO variation. The process of α-mangosteen elucidation with the stationary phase of CaO/SiO2 composite also showed the important role of the eluent polarity.