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mixed micelles

JooChuan Ang, Dan Ma, Benson Thomas Jung, Sinan Keten, Ting Xu
Ligand-functionalized, multivalent nanoparticles have been extensively studied for biomedical applications from imaging agents to drug delivery vehicles. However, the ligand cluster size is usually heterogeneous and the local valency is ill-defined. Here, we present a mixed micelle platform hierarchically self-assembled from a mixture of two amphiphilic 3-helix and 4-helix peptide-PEG-lipid hybrid conjugates. We demonstrate that the local multivalent ligand cluster size on the micelle surface can be controlled based on the coiled-coil oligomeric state...
August 17, 2017: Biomacromolecules
Gabriel S Vignoli Muniz, Jimmy Llontop Incio, Odivaldo C Alves, Klaus Krambrock, Letícia R Teixeira, Sonia R W Louro
The stability of ternary copper(II) complexes of a heterocyclic ligand, L (L being 2,2'-bipyridine (bipy) or 1,10-phenanthroline (phen)) and the fluorescent antibacterial agent norfloxacin (NFX) as the second ligand was studied at pH7.4 and different ionic strengths. Fluorescence quenching upon titration of NFX with the binary complexes allowed to obtain stability constants for NFX binding, Kb, as a function of ionic strength. The Kb values vary by more than two orders of magnitude when buffer concentration varies from 0...
August 5, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
Jinhai Huang, Wenwen Wang, Jing Yu, Xinxin Yu, Qianqian Zheng, Fangli Peng, Zhifen He, Wenguang Zhao, Zhaoliang Zhang, Xingyi Li, Qinmei Wang
Corneal neovascularization (CNV) is one of the leading causes of vision loss and a high-risk factor for transplant rejection. The present study proposed a supramolecular hydrogel comprised of MPEG-PCL micelles and α-cyclodextrin (α-CD) for co-delivery of dexamethasone sodium phosphate (Dexp) and Avastin(®) (Ava), and further evaluated its therapeutic efficacy in rat alkali burn model. A physical mixing of Dexp/Ava, MPEG-PCL micelles, and α-CD aqueous solution leads to a spontaneous formation of the supramolecular hydrogel via a "host-guest" recognition between MPEG and α-CD...
July 25, 2017: Colloids and Surfaces. B, Biointerfaces
Karsten Vogtt, Gregory Beaucage, Michael Weaver, Hanqiu Jiang
Worm-like micelles (WLMs) are nano-scale self-assemblies widely used for viscosity enhancement, for drug delivery, and in personal care products. The stability of WLMs under variable ionic and surfactant concentrations is important to applications of these fascinating materials. In this work it is demonstrated that a virial approach can be used to understand and predict WLM stability. A mixed surfactant system consisting of sodium laureth sulfate and cocoamidopropyl betaine was examined using small-angle neutron scattering...
August 7, 2017: Soft Matter
Zhikun Wang, Shuangqing Sun, Chunling Li, Songqing Hu, Roland Faller
Multicompartment nanostructures, such as microcapsules with clearly separated shell and core, are not easily accessible by conventional block copolymer self-assembly. We assess a versatile computational strategy through cooperative assembly of diblock copolymer blends to generate spherical and cylindrical compartmentalized micelles with intricate structures and morphologies. The co-assembly strategy combines the advantages of polymer blending and incompatibility-induced phase separation. Following this strategy, various nanoassemblies of pure AB, binary AB/AC and ternary AB/AC/AD systems such as compartmentalized micelles with sponge-like, Janus, capsule-like and onion-like morphologies can be obtained...
August 2, 2017: Soft Matter
Handi Yin, Peizhu Zheng, Jihua Zhao, Weiguo Shen
The heats of mixing for a series of DTAB/TX100 mixed surfactant aqueous solutions were measured by flow-mixing calorimetry and isothermal titration calorimetry (ITC) at 298.15 K and 85 kPa, which were used to calculate the inter-micellar interaction enthalpies (-ΔHC). The signs of -ΔHC for pure DTAB and TX100 micellar systems were contrary to the inter-micellar interaction parameters reported for the same systems in the literature, suggesting that these interaction parameters might have a Gibbs free energy character dominated by entropy changes...
August 2, 2017: Soft Matter
Zhou Zhou, Claire Dunn, Ibrahim Khadra, Clive G Wilson, Gavin W Halbert
The absorption of poorly water-soluble drugs is influenced by the luminal gastrointestinal fluid content and composition which controls solubility. Simulated intestinal fluids have been introduced into dissolution testing including endogenous amphiphiles and digested lipids at physiological levels; however, in vivo individual variation exists in the concentrations of these components, which will alter drug absorption through an effect on solubility. The use of a factorial design of experiment and varying media by introducing different levels of bile, lecithin and digested lipids has been previously reported, but here we investigate the solubility variation of poorly-soluble drugs through more complex biorelevant amphiphile interactions...
July 27, 2017: Molecular Pharmaceutics
Dan Zou, Wei Wang, Daoxi Lei, Ying Yin, Peng Ren, Jinju Chen, Tieying Yin, Bochu Wang, Guixue Wang, Yazhou Wang
For the treatment of glioma and other central nervous system diseases, one of the biggest challenges is that most therapeutic drugs cannot be delivered to the brain tumor tissue due to the blood-brain barrier (BBB). The goal of this study was to construct a nanodelivery vehicle system with capabilities to overcome the BBB for central nervous system administration. Doxorubicin as a model drug encapsulated in ganglioside GM1 micelles was able to achieve up to 9.33% loading efficiency and 97.05% encapsulation efficiency by orthogonal experimental design...
2017: International Journal of Nanomedicine
Pengying Wu, Yali Jia, Fei Qu, Yue Sun, Pan Wang, Kun Zhang, Chuanshan Xu, Quanhong Liu, Xiaobing Wang
Targeting drug delivery remains a challenge in various disease treatment including cancer. The local drug deposit could be greatly enhanced by some external stimuli-responsive systems. Here we develop pluronic P123/F127 polymeric micelles (M) encapsulating curcumin (Cur) that are permeabilized directly by focused ultrasound, in which ultrasound triggers drug release. Tumor preferential accumulation and site-specific sonochemotherapy were then evaluated. Cur-loaded P123/F127 mixed micelles (Cur-M) exhibited longer circulating time and increased cellular uptake compared to free Cur...
August 9, 2017: ACS Applied Materials & Interfaces
Elena Venuti, Dmitry Shishmarev, Philip W Kuchel, Shoma Dutt, Caron S Blumenthal, Kevin J Gaskin
INTRODUCTION: Bile salt stimulated lipase (BSSL; Enzyme Commission (EC) number has been a candidate triglyceridase for improving enzyme therapy for pancreatic insufficiency; however, its efficacy is near absent. We hypothesise that similarly to pancreatic lipase, BSSL is inhibited by phospholipids and this inhibition is relieved by Phospholipase A2 (PLA2; EC, and the present study was undertaken to explore this possibility. MATERIALS AND METHODS: Synthetic emulsions of triglyceride and phosphatidylcholine (PC) or lysophosphatidylcholine (LPC)/bile salt mixed micelles were used as a model of intestinal digestion-media...
July 21, 2017: Journal of Cystic Fibrosis: Official Journal of the European Cystic Fibrosis Society
Véronique Wintgens, József G Harangozó, Zsombor Miskolczy, Jean-Michel Guigner, Catherine Amiel, László Biczók
The effect of headgroup variation on the association of supramolecular amphiphiles composed of 4-sulfonatocalix[6]arene (SCX6) and cationic surfactant possessing tetradecyl substituent was studied in aqueous solutions at pH 7. When the surfactant contained hydrophilic trimethylammonium, pyridinium, or 1-methylimidazolium headgroup, highly reversible temperature-responsive nanoparticle-supramolecular micelle transformation could be attained at appropriately chosen component mixing ratios and NaCl concentrations...
August 1, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Goutam Mondal, Saud Almawash, Amit Kumar Chaudhary, Ram I Mahato
Gemcitabine (GEM), a first-line chemotherapy for pancreatic cancer undergoes rapid metabolism and develops chemoresistance after repeated administration. We previously demonstrated that the combination of GEM and miR-205 provides an effective therapeutic strategy to sensitize GEM-resistant pancreatic cancer cells. Since epidermal growth factor receptor (EGFR) is overexpressed in pancreatic cancer cells, in this study, we aimed to deliver mixed micelles containing GEM and miR-205 decorated with EGFR-targeting cetuximab (C225) monoclonal antibody for targeted therapy...
July 31, 2017: Molecular Pharmaceutics
Yu Wang, Tao Gong, Zhi-Rong Zhang, Yao Fu
Matrix stiffness regulates cell behavior in various biological contexts. In breast tumors, the deposition of extracellular matrix correlates with increasing matrix stiffness and poor survival. Nanoparticulate carriers represent a promising therapeutic vehicle for disease diagnosis and efficient anticancer drug delivery. However, how matrix stiffness influences cellular uptake of nanoparticles remains largely unexplored. Here, we selected photopolymerized polyacrylamide gels with varying stiffnesses as model substrates and studied the impact of matrix stiffness on cell morphology and nanoparticle uptake efficiency in two representative breast cancer cell lines with varying invasiveness, that is, MCF-7 with low invasiveness and MDA-MB-231 with high invasiveness...
August 9, 2017: ACS Applied Materials & Interfaces
Robert J Ono, Ashlynn L Z Lee, Zhi Xiang Voo, Shrinivas Venkataraman, Bei Wei Koh, Yi Yan Yang, James L Hedrick
Biodegradable polycarbonate-based ABA triblock copolymers were synthesized via organocatalyzed ring-opening polymerization and successfully formulated into chemically cross-linked hydrogels by strain-promoted alkyne-azide cycloaddition (SPAAC). The synthesis and cross-linking of these polymers are copper-free, thereby eliminating the concern over metallic contaminants for biomedical applications. Gelation occurs rapidly within a span of 60 s by simple mixing of the azide- and cyclooctyne-functionalized polymer solutions...
July 21, 2017: Biomacromolecules
Diana Mańko, Anna Zdziennicka, Bronisław Jańczuk
Measurements of the surface tensions, densities and viscosities of aqueous solutions of Triton X-100 (TX-100) and rhamnolipid (RL) mixtures, at constant concentration of RL or TX-100, were carried out. The measured values of the surface tension were compared to those determined using different theoretical models and on the basis of the surface tension of aqueous solutions of individual surfactants. From the surface tension isotherms, the Gibbs surface excess concentration of TX-100 and RL, the composition of surface layer and the standard Gibbs free energy of adsorption at the water-air interface were determined...
2017: Journal of Solution Chemistry
Ting Zhang, Songlei Zhou, Yang Liu, Xiang Luo, Donghua Di, Yanzhi Song, Xinrong Liu, Yihui Deng
In our previous study, polysialic acid-octadecyl dimethyl betaine (PSA-BS18) was synthesized and modified liposomal EPI. Preliminary experiments revealed that the PSA-BS18 was a potential material for targeting tumor site with superior curative effects. In this study, PSA-BS18 and Pluronic F127 (F127) mixed polymeric micelles encapsulated docetaxel (DTX) (FP/DTX) were prepared by a self-assembly method. The FP/DTX was found to have a diameter of 34.83 ± 0.50 nm with a narrow polydispersity, the entrapment efficiency was 99...
July 5, 2017: Drug Development and Industrial Pharmacy
Leonardo Chiappisi, Stephen David Leach, Michael Gradzielski
The formation of water insoluble polyelectrolyte/surfactant complexes (PESCs) upon mixing two homogeneous polycation/anionic surfactant and polycation/nonionic surfactant solutions is reported here. This phase separation is unexpected and differs markedly from the commonly observed enhanced solubility of colloidal systems in mixed surfactant systems. The study was performed on mixtures of the cationic biopolysaccharide chitosan (poly d-glucosamine) and mixed micelles composed of an ethoxylated fatty alcohol and its carboxylic acid terminated equivalent...
July 26, 2017: Soft Matter
Birgit Scholz, Renate Weiherer, Karl-Heinz Engel
The effects of thermooxidation of a phytosteryl/-stanyl and a phytostanyl fatty acid ester mixture on cholesterol micellarization were investigated using an in vitro digestion model simulating enzymatic hydrolysis by cholesterol esterase and subsequent competition of the liberated phytosterols/-stanols with cholesterol for incorporation into mixed micelles. As a first step, relationships between different doses of the ester mixtures and the resulting micellarized cholesterol were established. Subsequent subjection of the thermooxidized ester mixtures to the in vitro digestion model resulted in three principal observations: (i) thermal treatment of the ester mixtures led to substantial decreases of the intact esters, (ii) in vitro digestion of cholesterol in the presence of the thermooxidized ester mixtures resulted in significant increases of cholesterol micellarization, and (iii) the extents of the observed effects on cholesterol micellarization were strongly associated to the remaining contents of intact esters...
June 30, 2017: Steroids
Josy Ter Beek, Maximilian Kahle, Pia Ädelroth
For detailed functional characterization, membrane proteins are usually studied in detergent. However, it is becoming clear that detergent micelles are often poor mimics of the lipid environment in which these proteins function. In this work we compared the catalytic properties of the membrane-embedded cytochrome c-dependent nitric oxide reductase (cNOR) from Paracoccus (P.) denitrificans in detergent, lipid/protein nanodiscs, and proteoliposomes. We used two different lipid mixtures, an extract of soybean lipids and a defined mix of synthetic lipids mimicking the original P...
June 28, 2017: Biochimica et Biophysica Acta
Claudia Dähling, Gudrun Lotze, Hideharu Mori, Dmitry V Pergushov, Felix A Plamper
The kinetics of interpolyelectrolyte complexation involving architecturally complex (star-like) polymeric components is addressed. Specifically, the spontaneous coupling of branched cationic star-shaped miktoarm polymers, i.e., quaternized poly(ethylene oxide)114-(poly(2-(dimethylamino)ethyl methacrylate)17)4 (PEO114-(qPDMAEMA17)4), and temperature-sensitive linear anionic diblock copolymers poly(vinyl sulfonate)31-b-poly(N-isopropylacrylamide)27 (PVS31-b-PNIPAM27) and further rearrangements of the formed complexes were investigated by means of stopped-flow small-angle X-ray scattering (SAXS)...
June 29, 2017: Journal of Physical Chemistry. B
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