Characterization of Retinol Stabilized in Phosphatidylcholine Vesicles with and without Antioxidants

Abstract

Retinol stability has been reported to be improved by encapsulation in liposomes, both with and without cholesterol. However, this improvement is limited because of lipid peroxidation. In this study, we compare the stability of retinol in phosphatidylcholine liposomes under ultraviolet (UV) light or standard room air, with and without the addition of antioxidants. Both butylated hydroxytoluene (BHT) and a proprietary mix (StoppOx) improved the shelf stability from <10 to over 30 d. The addition of cholesterol had no effect. Fluorescence imaging showed a heterogeneous distribution of retinol within the vesicles, including within the aqueous layer. Fluorescence lifetimes were equally heterogeneous. Under UV irradiation, StoppOx protected retinol for significantly longer than BHT and via different mechanisms. This suggests that natural antioxidants work well to improve the retinol stability, but that further work to determine the optimal vesicle structure remains to be performed.

Laser induced fluorescence spectroscopy analysis of kidney tissues: A pilot study for the identification of renal cell carcinoma

“…The excitation and collection fibers were all multimode, 200 μm core diameter and 0.22 numerical aperture. The number of accumulations (20), acquisition time for each accumulation (0.2 s), and the Laser power (180 μW) were optimized for recording autofluorescence. Each time before the spectral acquisition the spectrometer was calibrated using the Mercury-Argon calibration source.…”

“…The absorption maxima of retinol is found to be 325 nm with an emission maxima of 490 nm due to π-π transition of retinol's polyene chain [15]. The autofluorescence of retinol (Vitamin A) has been extensively utilized for confirming the presence and distribution of retinol in tissue and at cellular level [16][17][18][19][20].…”

“…Collagen 325 400 [31] NAD(P)H 290 350 440, 460 [31] Retinol 325 490 [15,20] Flavin adenine dinucleotide 450 535 [31] F I G U R E 3 Autofluorescence spectra of normal and malignant (ccRCC) renal tissues.…”

Evaluation of solvent effect on the effective interactions of Isotretinoin and Tretinoin: Isomeric forms of vitamin A

“…Typically, this vitamin exists as Retinal, Retinol, and Retinoic acidin many cosmetics and skincare products, serving to prevent collagen loss and ageing-related tissue damage. The biochemical structure of Vitamin A consists of a cyclic group with a linear chain that terminates with a non-polar/polar group [ [1] , [2] , [3] , [4] , [5] , [6] , [7] ]. Isotretinoin and Tretinoin are geometric isomers of Vitamin A that are applied in dermatology to treat acne and skin disorders.…”

Synthesis of Retinol-Loaded Lipid Nanocarrier via Vacuum Emulsification to Improve Topical Skin Delivery

“…Another approach has been studied for the stabilization of retinol. Specifically, nanodispersed systems, such as liposomes [ 11 ], nanoemulsions [ 12 ], polymeric encapsulation [ 13 ], electrostatic interaction [ 14 ] and lipid nanoparticles [ 15 , 16 ], have gained increasing importance as potential vehicles for the controlled delivery of cosmetics and for the optimized disposition of active ingredients in particular skin layers. Among these methods, lipid nanoparticles, such as solid lipid nanoparticles and nanostructured lipid carriers (NLC) for retinol encapsulation, have been studied extensively owing to well-tolerated carrier systems for dermal applications [ 15 , 16 ].…”