Layer-by-layer films containing emodin or emodin encapsulated in liposomes for transdermal applications

Abstract

Dermal drug release systems are an important area of research because they can be applied to the skin in a non-invasive procedure using a lower concentration of drugs. In this study, we have developed two types of Layer-by-Layer (LbL) films for releasing emodin (EM). In one system, EM was intercalated with poly(ethylenimine) PEI and poly(vinyl sufonate) (PVS) polyelectrolytes, forming (PEI/PVS)(PEI/EM); in another, EM was incorporated in liposomes obtained by mixing dipalmitoyl phosphatidyl glycerol (DPPG) and palmitoyl oleoyl phosphatidyl glycerol (POPG) lipids, forming (PEI/PVS)(PEI/DPPG-POPG-EM). UV-vis and FTIR spectroscopies were used to characterize the LbL films. These showed that the depositions of material by LbL were efficient, with increases in the absorbance of each bilayer evidencing the presence of EM in the film. The (PEI/PVS)(PEI/EM) and (PEI/PVS)(PEI/DPPG-POPG-EM) films released EM in three and five days, respectively. The cyclic voltammetry (CV) assay of the (PEI/PVS)(PEI/EM) results are in agreement with UV-vis measurements, which suggest that EM was protonated in acid environments, while the CV of (PEI/PVS)(PEI/DPPG-POPG-EM) demonstrated distinct protonation behaviour for EM within the inner liposome structure, even in acid solutions. Therefore, this study presents two systems based on LbL films and provides additional details about the release of EM from these films to create a viable alternative for transdermal applications.

Boronic Acid Homopolymers as Effective Polycations for Sugar-Responsive Layer-by-Layer Assemblies

“…All LbL films were assembled with 2 initial (PEI/PVS)2 bilayers to minimize any interference with the quartz or glass substrate, 4 in a process as follows: (1) the substrate was immerse in PEI…”

“…Stimuli-responsive layer-by-layer (LbL) films have been widely investigated, in which the disassembly of the multilayer films can be stimulated by numerous triggers, such as pH, [1][2][3][4] ionic strength, 5 temperature, 6,7 light, 8,9 mechanical stimulation, 10,11 or in the presence of small biomolecules. [12][13][14][15][16] Typically, these external stimuli weaken the electrostatic interactions between adjacent layers, leading to disassembly of the LbL film.…”

Photoswitchable Layer-by-Layer Coatings Based on Photochromic Polynorbornenes Bearing Spiropyran Side Groups

“…solution (75 °C for 10 min), washed with DI water for 1 min, subsequently immersed in a HCl/H2O2/H2O (1:1:6, V:V:V) hydrophilization solution (75 °C for 10 min), and finally washed in DI water 24 . These treatments generate negative charges on the glass surface due to partial hydrolysis.…”

Long-Term Effect against Methicillin-Resistant Staphylococcus aureus of Emodin Released from Coaxial Electrospinning Nanofiber Membranes with a Biphasic Profile

“…However, its usage is limited due to its poor solubility in water and low oral bioavailability because of extensive glucuronidation in liver and intestine [12,15,16]. To improve its water solubility and bioavailability, various emodin-loaded delivery systems have been reported, such as nanoparticle [17], thermo-reversible gel [18], nanoemulsion [19], microspheres [20][21][22][23], liposome, layer-by-layer film [24], and electrospinning fiber membrane [25]. Among those delivery systems, electrospinning nanofiber membranes are a promising choice for wound dressing.…”