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Nurul Fadhilah Kamalul Aripin

Bio: Nurul Fadhilah Kamalul Aripin is an academic researcher from Universiti Teknologi MARA. The author has contributed to research in topics: Liquid crystal & Azobenzene. The author has an hindex of 7, co-authored 17 publications receiving 117 citations. Previous affiliations of Nurul Fadhilah Kamalul Aripin include University of Malaya & Korea University.

Papers
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Journal ArticleDOI
TL;DR: The dry state of glycosides, a family of glycolipids whose sugar headgroup is linked to the lipid chain via a glycosidic oxygen linker, is reviewed, and the structure property relationship of both linear and anhydrous Guerbet glycoside will be examined.
Abstract: Also recognized as carbohydrate liquid crystals, glycolipids are amphiphiles whose basic unit comprises of a sugar group attached to an alkyl chain. Glycolipids are amphitropic, which means these materials form liquid crystal self-assemblies when dry (thermotropic) as well as when dissolved in solvents (lyotropic/surfactants) such as water. Many glycolipids are also naturally derived since these can be found in cell membranes. Their membrane and surfactant functions are largely understood through their lyotropic properties. While glycolipids are expected to play major roles as eco-friendly surfactants in the global surfactant market, their usefulness as thermotropic liquid crystal material is, to date, unknown, due to relatively lack of research performed and data reported in the literature. Understandably since glycolipids are hygroscopic with many hydroxy groups, removing the last trace water is very challenging. In recent time, with careful lyophilization and more consistent characterization technique, some researchers have attempted serious studies into "dry" or anhydrous glycolipids. Motivated by possible developments of novel thermotropic applications, some results from these studies also provide surprising new understanding to support conventional wisdom of the lyotropic systems. Here we review the dry state of glycosides, a family of glycolipids whose sugar headgroup is linked to the lipid chain via a glycosidic oxygen linker. The structure property relationship of both linear and anhydrous Guerbet glycosides will be examined. In particular, how the variation of sugar stereochemistry (e.g. anomer vs. epimer), the chain length and chain branching affect the formation of thermotropic liquid crystals phases, which not only located under equilibrium but also far from equilibrium conditions (glassy phase) are scrutinized. The dry glycolipid assembly has been subjected to electric and magnetic fields and the results show interesting behaviors including a possible transient current generation.

23 citations

Journal ArticleDOI
TL;DR: In this paper, AMF and NFKA would like to thank the Royal Academy of Engineering for the award of the Newton Research Collaboration Programme grant NRCP1516/4/61.

22 citations

Journal ArticleDOI
TL;DR: A new mixture of alkyl glycosides derived from palm oil (PO) or palm kernel oil (PKO) was synthesised and showed high vitamin E encapsulation efficiency and low packing density of the membrane bilayer enabled more vitamin E to participate in the membrane formation.

20 citations

Journal ArticleDOI
TL;DR: Glycolipids prepared from palm kernel oil, PKO, in tropical regions represent an excellent opportunity to develop new surfactant formulations for cosmeceutical and pharmaceutical applications as mentioned in this paper.
Abstract: Glycolipids prepared from palm kernel oil, PKO, in tropical regions represent an excellent opportunity to develop new surfactant formulations for cosmeceutical and pharmaceutical applications while...

15 citations

Journal ArticleDOI
TL;DR: The light-responsiveness of the polymers, via reversible trans-to-cis photoisomerization of azobenzene groups, and the local activation of conductivity at relatively low temperatures, opens the possibility to prepare polymer electrolytes for energy conversion and storage, whose conductivity could be controlled and optimised by external stimuli, including light irradiation.
Abstract: In the search for novel smart multifunctional liquid crystalline materials, we report the synthesis, thermal and structural characterisation, and the conductivity, of a set of new block and statistical copolymers, containing light-responsive mesogenic groups (MeOAzB), polar sulfonic acids (AMPS), and methyl(methacrylate) groups (MMA). By using a cascade of reversible addition-fragmentation chain polymerisations, RAFT, we have tailored different side-chain polymeric structures by controlling monomer composition (MeOAzB/AMPS/MMA) and configuration. We have yielded simultaneous liquid crystalline behaviour and appreciable conductivity in polymers with low concentrations of polar acid groups, by the formation of smectic phases in narrow aggregates. The light-responsiveness of the polymers, via reversible trans-to-cis photoisomerization of azobenzene groups, and the local activation of conductivity at relatively low temperatures, opens the possibility to prepare polymer electrolytes for energy conversion and storage, whose conductivity could be controlled and optimised by external stimuli, including light irradiation.

12 citations


Cited by
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01 Dec 2007

1,121 citations

Book ChapterDOI
18 May 2006
TL;DR: In this paper, a liquid crystal is defined as a mixture of a liquid and a columnar phase, and the following properties of the liquid crystal: 1 1.1 What is a Liquid Crystal? 2 1.2 Cholesterics.
Abstract: 1 What is a liquid crystal 2 1.1 Nematics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.2 Cholesterics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.3 Smectics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.4 Columnar phases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1.5 Lyotropic liquid crystals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

325 citations

Journal ArticleDOI
TL;DR: This manuscript reviews important facets of lipid-based vesicles as drug carriers and their surface modifications to achieve controlled release and selective cell targeting and dedicated a section of this review to summarise some novel applications of various lipid liquid crystal phases in drug delivery.
Abstract: Vesicles formed by self-assembly of lipids and surfactants are increasingly recognised as carriers for drug delivery applications in disease targeting and many other biomedical-related areas, demonstrable by the growing number of significant publications. This manuscript reviews important facets of lipid-based vesicles as drug carriers and their surface modifications to achieve controlled release and selective cell targeting. We cover both the more commonly used ionic phospholipid vesicle carriers and the rapidly growing field of non-ionic vesicles/niosomes using self-assembly of uncharged amphiphilic molecules, which could be formed by using sugar surfactants or glycolipids, sorbitan esters, and polyoxyethylene alkyl ethers. Due to their lower cost, biodegradability, low-toxicity, low-immunogenicity and specific sugar-cell recognition, much attention would be devoted to glycolipid bio-surfactants as potential carriers for targeted delivery. Specifically, our review points to the design consideration of lipid and surfactant nano-carriers based on critical packing parameter, membrane curvature, and the effects of hydrophobic chain structures. We have also dedicated a section of this review to summarise some novel applications of various lipid liquid crystal phases in drug delivery, and how in turn these are related to chemical structures of the lipid entities. The final section of this review outlines the application of lipid vesicles as delivery agents for diagnostic imaging.

78 citations

Book
01 Jan 1919
TL;DR: Cumming and Kay as mentioned in this paper present a textbook of quantitative analysis for students in universities and technical schools, which is very practical, and gives many hints to students which will save the time of teachers.
Abstract: THE first edition of this book was published in 1913, and the appearance of the fourth edition less than ten years later shows that it has been found in practice a most useful guide to students. The present volume should provide a sound course of quantitative analysis for students in universities and technical schools. It is very practical, and gives many hints to students which will save the time of teachers. The reduction method with Devarda's alloy might have been given for the estimation of nitrates, instead of the one with reduced iron, which is less satisfactory. In the description of the Lunge nitrometer no mention is made of the important correction for the solubility of nitric oxide in the acid. The directions for the preparation of cupferron reagent on p. 410 will be found useful, as the price charged for this substance is almost prohibitive.A Text-book of Quantitative Chemical Analysis.By Dr. A. C. Cumming Dr. S. A. Kay. Fourth edition. Pp. xv + 432. (London: Gurney and Jackson; Edinburgh: Oliver and Boyd, 1922.) 15s. net.

76 citations

12 May 2013
TL;DR: The ability of quaternary ammonium surfactants and sterols to self-assemble, forming stable amphiphilic bimolecular building-blocks with the appropriate structural characteristics to form in aqueous phases, closed bilayers, named quatsomes, with outstanding stability, with time and temperature is shown.
Abstract: Thermodynamically stable nanovesicle structures are of high interest for academia and industry in a wide variety of application fields, ranging from preparation of nanomaterials to nanomedicine. Here, we show the ability of quaternary ammonium surfactants and sterols to self-assemble, forming stable amphiphilic bimolecular building-blocks with the appropriate structural characteristics to form in aqueous phases, closed bilayers, named quatsomes, with outstanding stability, with time and temperature. The molecular self-assembling of cholesterol and surfactant cetyltrimethylammonium bromide (CTAB) was studied by quasi-elastic light scattering, cryogenic transmission electron microscopy, turbidity (optical density) measurements, and molecular dynamic simulations with atomistic detail, upon varying the cholesterol-to-surfactant molar ratio. As pure species, CTAB forms micelles and insoluble cholesterol forms crystals in water. However, our molecular dynamic simulations reveal that the synergy between CTAB and cholesterol molecules makes them self-assemble into bimolecular amphiphiles and then into bilayers in the presence of water. These bilayers have the same structure of those formed by double-tailed unimolecular amphiphiles.

73 citations