Table 4.

Method of Vitamin E detection when it is combined with biomaterials.

Technique	Combined Material	Molecule Detected	Method	Information	Ref.
HPLC	UHWMPE	α-tocopherol	HPLC connected to UV/Vis diode array detector at 297 nm, construction of calibration curve of HPLC peak area.	Quantitative	[108]
	UHWMPE	α-tocopherol	HPLC connected to UV/Vis diode array detector, construction of calibration curve of absorbance peak area at 290 nm	Quantitative	[109]
	Collagen mesh	α-tocopherol	HPLC connected to a fluorescence detector, detection at excitation wavelength of 290 nm and emission wavelength of 330 nm	Quantitative	[112]
	Alginate and hyaluronate film	α-tocopherol acetate	HPLC connected to UV/Vis diode array detector, construction of calibration curve of absorbance peak area at 285 nm	Quantitative	[44]
	Hyaluronic-acid-based β-cyclodextrin copolymer	α-tocopherol	HPLC connected to UV/Vis diode array detector	Quantitative	[64]
	PNIPAM-b-PCL-b-PNIPAM copolymer	α-tocopherol	HPLC equipped with a differential refraction index detector	Quantitative	[65]
UV-VIS	UHWMPE	α-tocopherol	Construction of calibration curve of absorbance peak area at 290 nm	Quantitative	[110]
	UHWMPE	α-tocopherol	Analysis of reflectance spectra which presents a minimum around 290 nm and a decrease of reflectance at 400–500 nm.	Detection	[111]
	Hyaluronic acid	α-tocopherol succinate	Construction of calibration curve of absorbance peak area at 285 nm	Quantitative	[116]
	PLA+PCL	α-tocopherol acetate	Construction of calibration curve of absorbance peak area at 284 nm	Quantitative	[42]
Colorimetric Assay	UHWMPE	α-tocopherol	The yellowing of the sample was analysed through three parameters (a,b,L) of CIELAB colour space, and a calibration curve of colour distances was constructed.	Quantitative	[111]
FTIR-ATR	UHWMPE	α-tocopherol	Analysis of peaks. For quantitative analysis, calibration curve of these peaks is needed.	Analysis of Vitamin E transformation products in polymer samples prior to extraction and quantitative.	[108]
	Collagen	α-tocopherol	Analysis of main peaks	Characterization of film	[45]
FTIR-ATR	Magnetite	α -tocopheryl succinate	Analysis of main peaks	Characterization of chemical modification of nanoparticles	[71]
	Chitosan	α-tocopherol	Analysis of peaks	Physical bonds and chemical interactions are reflected by changes in characteristic spectral peaks.	[115]
	Chitosan	α-tocopherol	Analysis of peaks	Characterization of nanoparticles	[59]
	PCL/PLA	α-tocopherol acetate	Analysis of peaks	Characterization of membranes	[42]
	Soluplus	α-tocopherol	Analysis of peaks	Analysis of bonding between Soluplus/vitamin E	[114]
	Polyethylene	α-tocopherol	Analysis of peaks from 600–4000 cm −1	Analysis of interaction between vitamin E and chitosan	[113]
XPS	Polyethylene	α-tocopherol	All binding energies were referenced to the C1s peak at 285 eV.	Analysis of covalent bonding	[113]
DPPH	Polyethylene	α-tocopherol	The scavenging activity was estimated RSA (%) = (1 − (A sample/Acontrol)) × 100, measuring the adsorption at 515 nm after 30 min in dark condition.	Radical scavenging activity evaluation	[113]
	Chitosan	α-tocopherol	The scavenging activity was estimated RSA (%) = (1 − (A sample/Acontrol)) × 100, measuring the adsorption at 517 nm after 30 min in dark condition.	Radical scavenging activity evaluation	[115]
	Collagen/chitosan	α-tocopherol	DPPH were measured by the adsorption at 517 nm after 30 min in dark condition. DPPH loss which is a concentration of DPPH radicals reacted with antioxidants.	Antioxidant activity	[112]
Contact Angle	Polyethylene	α-tocopherol	Contact angle titrations were performed by measuring sets of contact angles at each pH value.	Analysis of hydrophobic behaviour as pH increases	[106]
	PLA	α-tocopherol	Static contact angle	Analysis of material wettability change	[48,49]