Table 3.

FTIR wavenumber and corresponding functional groups.

Material	Wavenumber (cm−1)		Functional Groups	Reference
	Result	Literature
α-mangostin	34,081; 32,204	3260	O–H stretch	[37]
	29,875; 26,078; 29,317	2989; 2962; 2924	C–H stretch
	16,338	1642	C=O
	14,435	1454	C–C
	11,782	1199	Ortho–OCH3 stretch
	107,533	1076	C–O–C stretch
Chitosan	350,954	347,868	O–H stretch dan N–H stretch	[38]
	289,424	292,413	C–H stretch
	165,302	165,688	C=O
	1597	157,105	N–H bend
	141,963	142,253	C–H bend
	137,816	137,816	C–N
	115,731	115,731	C–O–C stretch
	1079	102,518	C–O
Sodium tripolyphosphate	121,132	1210	νas P=O	[39]
	115,731	1130	νs O–P=O
	109,269	1090	νas PO3
	88,823	888	νas P–O–P
Kappa carrageenan	1262	1241	O=S=O
	1069	1069	Glycosidic bond
	929	922	3,6-anhydrogalactose	[40]
	846	847	Galactose-4-sulfate