Tailoring of the self-organized structure of sulfonated polyaniline from a fibrillar network to a colloidal aggregate

2003 ◽  
Vol 18 (7) ◽  
pp. 1691-1697 ◽  
Author(s):  
Tushar Jana ◽  
Arun K. Nandi

Self-organized structures of the sodium salt of sulfonated polyaniline (prepared from the leucoemeraldine base of polyaniline) in the presence of a mixture of cationic and nonionic surfactants were studied. It was used in the latex form, which has been prepared using a conventional method with sodium dodecyl sulfate. The cationic surfactant used was didodecyl dimethyl ammonium bromide, and the nonionic surfactant used was Triton-X-100. The supramolecular organization was made in aqueous medium by varying the concentrations of the components. A three-dimensional fibrillar network and colloidal aggregate were produced due to the supramolecular organization. The thermal study indicated reversible first-order phase transition in the former cases fulfilling the criteria of thermoreversible gels. A probable explanation of the different morphology from the variation of charge density on the vesicle surface has been offered. The conductivity of fibrillar network is two orders higher than that of the colloidal aggregate.

2016 ◽  
Vol 39 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Przemysław Siejak ◽  
Krzysztof Polewski

Abstract In this paper we present the results of measured physical parameters of self-organized structures consisting of hydrophobic functionalized silver nanoparticles and amphiphilic molecules capable of micelles formation. Those systems may be considered as simple models for transfer of nanoparticles through the biological membrane. Three different surfactants were used: negatively charged sodium dodecyl sulphite, SDS, neutral Triton X-100 and positively charged tetredodecyltrimethyl ammonium bromide, TTABr. We have found that hydrophobic functionalized Ag nanoparticles are encapsulated in neutral Triton X-100 micelles with a diameter of 10 nm without significant change in the size of the micelles. The efficiency of encapsulation of Ag by SDS micelles is lower compared to Triron X-100 and no incorporation of Ag nanoparticles into TTABr occurs. Obtained results indicate that in aqueous environment ionic properties of molecules creating micelles and concentration ratios between components determine the efficiency and kinetics of two competitive processes association or aggregation of nanoparticles and encapsulation of Ag nanoparticles within micelles.


2013 ◽  
Vol 409-410 ◽  
pp. 125-128
Author(s):  
Zheng Hua Wang ◽  
Xu Ming Yang ◽  
Bo Zhi Ren

Photodegradation of 1,2,4-trichlorobenzene (1,2,4-TCB) was examined in one kind of Gemini surfactant solution (ethylene dioctadecyl dimethyl ammonium bromide) and two kinds of conventional surfactant solutions (sodium dodecyl sulfate and polyoxyethylene polyoxypropylene ether). Compared with conventional surfactants, Gemini surfactants make up of two identical or different amphiphilic moieties connected by a spacer group. Under UV irradiation at 254 nm, 1,2,4-trichlorobenzene was decomposed in the three micellar solutions, but the photodegradation rate of 1,2,4-trichlorobenzene in the Gemini surfactant solution was 3.54% and 11.81% higher than those in other two conventional surfactant solutions respectively. Thus, the photochemical reactions of chlorobenzenes can be enhanced in Gemini surfactant solutions.


2011 ◽  
Vol 71-78 ◽  
pp. 122-125 ◽  
Author(s):  
Ling Li Song ◽  
Ren Yuan Zhang ◽  
Ling Bo Mao ◽  
Wen Jie Zhu ◽  
Miao Yan Zheng

The influences of dispersant type, supersonic time and concentration on the dispersion property of the nano-aluminium powders in glycol water were systematically studied by using Sodium dodecyl sulfate (SDS),cetyl trimethyl ammonium bromide (CTAB) and sodium hexa metah posphate(SHMP)as dispersants. During the first stage of the experiments, influences of dispersant type and ultrasonic time with these dispersants were evaluated. The next stage of the study was focused on SHMP concentration. The influence of SHMP concentration was assessed. The results show that with the increasing of ultrasonic time, the dispersion property of nano-aluminum powders first increases and then decreases, and SHMP is the best one. The excellent dispersing condition on the dispersion property of nano-aluminium is: 5g/L SHMP and 50 min ultrasonic vibration.


2013 ◽  
Vol 734-737 ◽  
pp. 2505-2508
Author(s):  
Lin Lin Cui ◽  
Hua Nan Guan

Dodecyl trimethyl ammonium bromide/sodium dodecyl benzene sulfonate (DTAB/SDBS) complex formulation of scale effect on the spontaneous formation of vesicles and the influence of different factors on the stability of vesicles were discussed, structure and morphology of vesicles were observed.


1977 ◽  
Vol 23 (3) ◽  
pp. 240-252 ◽  
Author(s):  
J. Boisvert ◽  
T. Yamamoto

Vaccinia virus particles were dissociated into their constituent polypeptides and analysed by sodium dodecyl sulfate (SDS) gel electrophoresis. Thirty-three distinct polypeptide bands were identified and their molecular weights ranged between 11 000 and 150 000 daltons.Specific staining of gels containing polypeptides of dissociated virions revealed the presence of eight glycopeptides. No lipopeptides were detected.Analysis of chemical extracts (urea, guanidine hydrochloride, and alkali treatment) of the virus by SDS gel electrophoresis indicated that a total of 10 to 14 different polypeptides ranging in molecular weights from 11 000 to 70 000 daltons were solubilized.Analysis of detergent extracts and of the remains of extracted viral particles has shown that the detergent Nonidet P-40 (NP-40) solubilized a total of 11 polypeptides of which 6 were glycopeptides. The other detergents sodium deoxycholate (SDC) and cetyl trimethyl ammonium bromide (CTAB) were not as selective, both solubilizing more than 25 of the polypeptides composing the virus. Gel electrophoresis results also indicated that most of the small molecular weight (11 000–70 000 daltons) polypeptides were readily solubilized by NP-40, SDC, and CTAB, while those with molecular weights of 70 000 daltons and higher were not well solubilized.The effects of detergents were also analysed by electron microscopy. Evidence was obtained for subpopulations of viral particles having different susceptibility to detergent extraction.


2018 ◽  
Vol 115 (48) ◽  
pp. 12188-12193 ◽  
Author(s):  
Amanda S. Chin ◽  
Kathryn E. Worley ◽  
Poulomi Ray ◽  
Gurleen Kaur ◽  
Jie Fan ◽  
...  

Our understanding of the left–right (LR) asymmetry of embryonic development, in particular the contribution of intrinsic handedness of the cell or cell chirality, is limited due to the confounding systematic and environmental factors during morphogenesis and a ack of physiologically relevant in vitro 3D platforms. Here we report an efficient two-layered biomaterial platform for determining the chirality of individual cells, cell aggregates, and self-organized hollow epithelial spheroids. This bioengineered niche provides a uniform defined axis allowing for cells to rotate spontaneously with a directional bias toward either clockwise or counterclockwise directions. Mechanistic studies reveal an actin-dependent, cell-intrinsic property of 3D chirality that can be mediated by actin cross-linking via α-actinin-1. Our findings suggest that the gradient of extracellular matrix is an important biophysicochemical cue influencing cell polarity and chirality. Engineered biomaterial systems can serve as an effective platform for studying developmental asymmetry and screening for environmental factors causing birth defects.


2009 ◽  
Vol 5 ◽  
pp. 135-142
Author(s):  
Jorge A. García-Macedo ◽  
A. Franco ◽  
Guadalupe Valverde-Aguilar ◽  
M.A. Ríos-Enríquez

The kinetics of the orientation of Disperse Red 1 (DR1) molecules embedded in nanostructured Polymethylmetacrylate (PMMA) films was studied under the effect of an intense constant electric poling field. The changes in the orientation distribution of the DR1 molecules were followed by Second Harmonic Generation (SHG) measurements. The SHG signal was recorded as function of time at three different temperatures. We focused on both, the signal increases under the presence of the poling field and the signal decays without the poling field. The studied PMMA films were nanostructured by the incorporation of ionic surfactants as the Sodium Dodecyl Sulfate (SDS) and the Cetyl Trimethyl Ammonium Bromide (CTAB) during their preparation. The kinds of nanostructures obtained in the films were determined by means of X-ray diffraction (XRD) measurements. Substantial differences in signal intensity and in growth and decay rates between amorphous and nanostructured films were found.


2011 ◽  
Vol 361-363 ◽  
pp. 1946-1949
Author(s):  
Yi Fei Li ◽  
Tian Wei Qian ◽  
Li Juan Huo

In this paper,the effect of surfactant to the infiltration and the change of saturated hydraulic conductivity was studied by GUELPH PERMEAMETER. We investigated effects on soil infiltration by three representative surfactants.The results show that the existing of sodium dodecyl benzene sulfonate (SDBS), cetyl trimethyl ammonium bromide bromide (CTAB) and polyxyethylene fatty alcohol (AEO9) would decrease soil saturated hydraulic conductivity.


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