Physicochemical Analysis of DPPC and Photopolymerizable Liposomal Binary Mixture for Spatiotemporal Drug Release

Abstract

The development of a spatiotemporal drug delivery system with a long release profile, high loading efficiency, and robust therapeutic effects is still a challenge. Liposomal nanocarriers have secured a fortified position in the biomedical field over decades. Herein, liposomal binary mixtures of 1,2-dipalmitoyl- sn-glycero-3-phosphocholine (DPPC) and photopolymerizable 1,2-bis(10,12-tricosadiynoyl)- sn-glycero-3-phosphocholine (DCPC) phospholipids were prepared for drug delivery applications. The diacetylenic groups of DCPC produce intermolecular cross-linking following UV irradiation. Exposure of the liposomal mixture to 254 nm radiation induces a pore within the lipid bilayer, expediting the release of its entrapped 5,6-carboxyfluorescein dye. The dosage and rate of the released content are highly dependent on the number and size of the induced pore. Photochemical cross-linking studies at different exposure times were reported through the analysis of UV-visible spectrophotometry, nano differential scanning calorimetry, Fourier transform infrared spectroscopy, and Raman spectroscopy. The optimal irradiation time was established after 8 min of exposure, inducing lipid cross-linking with minimal oxidative degradation, which plays an essential role in the pathogenesis of numerous diseases due to the formation of primary and secondary oxidation products, accordingly reducing the encapsulated drug therapeutic level.

Photochemical aging of atmospherically reactive organic compounds involving brown carbon at the air-aqueous interface

“…When considering the liposomal binary mixture of phospholipids containing 1,2-bis(10,12-tricosadiynoyl)-sn-glycero-3-phosphocholine (DC 8,9 PC) and DPPC, DC 8,9 PC can produce intermolecular cross-linking following the release of 5,6-carboxyfluorescein dye under UV irradiation. The same photochemical reaction had no effect on DPPC molecules, even when exposed to radiation with a wavelength of 254 nm, which carries relatively greater energy (Kenaan et al, 2018). Both DSPC and DPPC molecules possess the same phosphocholine head and saturated aliphatic chain, which is likely why there rather similar activity of DPPC and DSPC with the photosensitizer under irradiation.…”

Near-Infrared Photo-controlled Permeability of a Biomimetic Polymersome with Sustained Drug Release and Efficient Tumor Therapy

“…However, the complete disruption of the polymersome structure results in the uncontrolled burst release mode. 16−18 This could not maintain the drug release profile over a long period of time, 19−21 therefore requiring frequent dosing 22 or resulting in a multidrug resistance (MDR) effect 23,24 and impairing the therapeutic effect.…”

“…Synthetic amphiphiles have biolipid-like structures and can self-assemble into polymersomes in aqueous solutions with structures like naturally originated vesicles. , Compared with liposomes, the mechanical robustness and convenience of functionalization − increase polymersome stability during the delivery process and improve targeting with controlled release, therefore making them particularly appealing as biomimetic nanocarriers and nanoreactors. − By endowing them with responsiveness toward stimuli such as specific biomarkers − and microenvironments, − “on-demand” drug delivery has been achieved. However, the complete disruption of the polymersome structure results in the uncontrolled burst release mode. − This could not maintain the drug release profile over a long period of time, − therefore requiring frequent dosing or resulting in a multidrug resistance (MDR) effect , and impairing the therapeutic effect.…”

Improving the Sensory Properties of Layered Phospholipid-Graphene Films Due to the Curvature of Graphene Layers

“…The aim of this paper is to find a way to improve the sensory properties of phospholipid-graphene films by curving graphene monolayers using in silico computational methods. In this paper, we consider only DPPC (dipalmitoylphosphatidylcholine) molecules, since they are part of the cell membrane and liposomes used actively in biomedicine [ 29 , 30 , 31 , 32 , 33 ], although other types of phospholipid molecules can also be used.…”