Effects of Anionic Surfactants on the Water Permeability of a Model Stratum Corneum Lipid Membrane

Lee, Sang-Wook,Tettey, Kwadwo E.,Yarovoy, Yury,Lee, Daeyeon American Chemical Society 2014 Langmuir Vol.30 No.1

<P>The stratum corneum (SC) is the ourtermost layer of the epidermis and has a brick-and-mortar-like structure, in which multilamellar lipid bilayers surround flattened dead cells known as corneocytes. The SC lipid membranes provide the main pathway for the transport of water and other substances through the SC. While the physicochemical properties of the SC can be affected by exogenous materials such as surfactants, little is known about how the water barrier function of the SC lipid membranes is compromised by common surfactants. Here, we study the effect of common anionic surfactants on the water permeability of a model SC lipid membrane using a quartz crystal microbalance with dissipation monitoring (QCM-D). Particularly, the effect of sodium dodecyl sulfate (SDS) and sodium lauryl ether sulfate (SLES) is compared. These two surfactants share commonality in their molecular structure: sulfate in the polar headgroup and the same apolar tail. The mass of the lipid membranes increases after the surfactant treatment at or above the critical micelle concentration (CMC) of the surfactants due to their absorption into the membranes. The incorporation of the surfactants into the lipid membranes is also accompanied by partial dissolution of the lipids from the model SC lipid membranes as confirmed by Fourier-transform infrared (FT-IR) spectroscopy. Although the water sorption of pure SDS is much lower than that of pure SLES, the water sorption of SDS-treated membranes increases significantly similar to that of SLES-treated membranes. By combining QCM-D and FT-IR spectroscopy, we find that the chain conformational order and stiffness of the lipid membranes decrease after SDS treatment, resulting in the increased water sorption and diffusivity. In contrast, the conformational order and stiffness of the SLES-treated lipid membranes increase, suggesting that the increased water sorption capacity of SLES-treated lipid membranes is due to the hygroscopic nature of SLES.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/langd5/2014/langd5.2014.30.issue-1/la403138a/production/images/medium/la-2013-03138a_0007.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/la403138a'>ACS Electronic Supporting Info</A></P>

Effect of Simple Formulas of Muscle Section in Donguibogam on Myogenic Regulatory Factors and IGF-1 Expression in C2C12 Cells

In Jun Yang,Clement Tettey,Heung Mook Shin 한의병리학회 2014 동의생리병리학회지 Vol.28 No.4

In-vitro anticancer activity of green synthesized silver nanoparticles on MCF-7 human breast cancer cells

Jang, Suk Ju,Yang, In Jun,Tettey, Clement O.,Kim, Ki Mo,Shin, Heung Mook Elsevier 2016 Materials science & engineering. C, Materials for Vol.68 No.-

<P>In recent years, green synthesis of metallic nanoparticles is a growing area of research because of their potential applications in nanomedicine. In the present study we synthesized silver nanoparticles (silver NPs) from AgNO3 using aqueous extract of Lonicera hypoglauca flower as reducing and capping agents. The synthesized silver NPs were characterized using IJV Vis spectroscopy, FTIR, SEM-ED, TEM and SAED. Silver NPs were found to be significantly toxic to MCF-7 cells via the induction of apoptosis whereas sparing normal immune system (RAW 264.7) cells. (C) 2016 Elsevier B.V. All rights reserved.</P>

Geometrically and chemically anisotropic particles at an oil–water interface

Park, Bum Jun,Choi, Chang-Hyung,Kang, Sung-Min,Tettey, Kwadwo E.,Lee, Chang-Soo,Lee, Daeyeon The Royal Society of Chemistry 2013 Soft matter Vol.9 No.12

<P>We present the behaviour of particles with chemical and geometrical anisotropy at a planar oil–water interface. We find that Janus cylinders with a small aspect ratio adopt an upright configuration, whereas the particles with a large aspect ratio exhibit both the upright and tilted configurations, which can be explained by the presence of two minima in the attachment energy profile. Such unique configurations significantly affect their assembly structure and lateral interactions. In particular, we observe strong capillary attractions between two tilted Janus cylinders and show that the scaling behaviour of the interaction depends on the lateral alignments of two cylinders. Consequently, this capillarity leads to a variety of assembled structures, which we attribute to the quasi-quadrupolar interface deformation observed around each particle.</P> <P>Graphic Abstract</P><P>Geometrical and chemical anisotropy of Janus cylinders leads to diverse configurations and assembly behaviours at an oil–water interface. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c3sm27635j'> </P>

Enhanced photocatalytic activity of Ag/g-C₃N₄ composite

Nagajyothi, P.C.,Pandurangan, M.,Vattikuti, S.V.P.,Tettey, C.O.,Sreekanth, T.V.M.,Shim, J. Elsevier Science B.V 2017 Separation and purification technology Vol.188 No.-

Silver-graphite carbon nitride (Ag/g-C<SUB>3</SUB>N<SUB>4</SUB>) was designed and synthesized through a simple green chemical route. The photocatalyst was comprehensively characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), High-resolution transmission electron microscopy (HR-TEM), and X -ray photoelectron spectroscopy (XPS). The HR-TEM results indicate that the synthesized Ag spherical-like nanoparticles were randomly loaded on the surface of graphitic carbon nitride (g-C<SUB>3</SUB>N<SUB>4)</SUB>. In addition, the Ag/g-C<SUB>3</SUB>N<SUB>4</SUB> nanocomposites exhibited 2.5 times higher photocatalytic activity than pristine g-C<SUB>3</SUB>N<SUB>4</SUB> for the degradation of malachite green (MG) dye under UV irradiation.

Ultra-sonication-assisted silver nanoparticles using <i>Panax ginseng</i> root extract and their anti-cancer and antiviral activities

Sreekanth, T.V.M.,Nagajyothi, P.C.,Muthuraman, P.,Enkhtaivan, G.,Vattikuti, S.V.P.,Tettey, C.O.,Kim, Doo Hwan,Shim, Jaesool,Yoo, Kisoo Elsevier 2018 Journal of photochemistry and photobiology Biology Vol.188 No.-

<P><B>Abstract</B></P> <P>A simple, inexpensive ultra-sonication method was used to synthesize quasi spherical silver nanoparticles (AgNPs) with an aqueous extract from <I>Panax ginseng</I> roots. This method has the advantages of being completely eco-friendly and allows increased reaction rates, uniform dispersal of the nanoparticles in liquids, and effective breaking of aggregates. Biomolecules present in plant extracts are often used to reduce metal ions to nanoparticles in a single-step green synthesis route. The formation of the AgNPs was characterized using UV–visible (UV–vis) spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), energy- dispersive X-ray analysis (EDX), Fast Fourier Transform (FFT), and high-resolution transmission electron microscopy (HR-TEM). The formation of AgNPs (456 nm) was confirmed by UV–vis spectroscopy. HR-TEM analysis revealed that most of the AgNPs were quasi spherical with sizes ranging from approximately 5 to 15 nm. The crystalline nature of the AgNPs was confirmed by XRD, and the presence of elemental silver was confirmed by energy-dispersive X -ray analysis. The AgNPs showed dose-dependent cytotoxicity towards HeLa cells in vitro (3.88% at 0.005 M, 5.11% at 0.01 M, 7.52% at 0.015 M, 11.19% at 0.02 M, and 19.45% at 0.025 M) as revealed by sulforhodamine B assay. They were also shown to be virucidal against the influenza A virus (strain A/PR/8). Hence, the present facile, eco-friendly, and efficient method results in the synthesis of AgNPs that can act as an alternative biomaterial for future biomedical applications.</P> <P><B>Highlights</B></P> <P> <UL> <LI> AgNPs synthesized via green route using <I>Panax ginseng</I> root aqueous extract. </LI> <LI> AgNPs were spherical in shape, with a crystallite size of 5 to 15 nm. </LI> <LI> In addition, the green synthesized AgNPs were studied for in-vitro cytotoxic and antiviral activities. </LI> </UL> </P> <P><B>Graphical Abstract</B></P> <P>[DISPLAY OMISSION]</P>