Nanocarriers of solid lipid from micelles of amino acids surfactants coated with polymer nanoparticles.

Polymer nanoparticle coated micelle assemblies of lauryl ester of tyrosine (LET) act as potential nanocarriers for the model solid lipid stearyl alcohol. The coating is afforded by a simple methodology of heterophase polymerization reaction of styrene or the mixture of styrene and butyl acrylate at a mole ratio of 0.8:0.

pH-responsive aggregation states of chiral polymerizable amphiphiles from L-tyrosine and L-phenyl alanine in water.

Sodium salts of maleamic acid derivatives of lauryl ester of tyrosine (MTNa) and phenyl alanine (MPNa) in water exhibited strong pH-responsive behaviors of viscosity and specific conductivity that originate from the concentration and pH dependence of their aggregation states. The aggregates were characterized by a novel spin-probe-partitioning electron paramagnetic resonance (SPPEPR) method and dynamic light scattering (DLS). Results of high-precision fitting of the second-harmonic EPR spectra of the small spin probe di-tert-butyl nitroxide (DTBN) in these aggregates together with viscosity, conductivity, and DLS showed that, at pH ~ 7.

Unprecedented relationship between the size of spherical chiral micellar aggregates and their specific optical rotations.

Transmission electron microscopy (TEM) images and fluorescence quenching methods indicated that lauryl ester of L-phenylalanine (LEP) and lauryl ester of L-tyrosine (LET) form spherical chiral micelles in the 50-200 mM range and their size increases with concentration. The number of molecules present in these spherical chiral aggregates varied from 80 to 160 for LEP and 80-100 for LET. The specific optical rotation, representing circular birefringence, for LEP at 405 nm and 32 °C is found to increase linearly from 37 deg cc g(-1) dm(-1) for an isolated molecule to 56 deg cc g(-1) dm(-1) for ∼200 nm size aggregate.

High performance controlled reactors from micellar assemblies of aromatic amino acid amphiphiles for nanoparticle synthesis.

The micellar assemblies of lauryl esters of tyrosine (LET) and phenylalanine (LEP) show extraordinary emulsification properties. The structural similarity in respect of the aromatic ring between the dispersed phase, styrene, and the surfactants facilitates solubilization of styrene up to four times the weight of LEP and 11 times that of LET. We propose that the solubilization site varies between core in the LEP and shell in the LET micelles.

Formation of self-aggregated structures of different types in water of chiral polymerizable amphiphiles from L-tyrosine and L-phenylalanine.

Sodium salts of maleamic acid derivatives from lauryl esters of L-tyrosine (MTNa) and L-phenylalanine (MPNa) were synthesized and characterized. The aggregated structures of MTNa and MPNa in water were investigated, employing several independent methods. MPNa showed secondary aggregated structures in contrast to MTNa at concentrations of >1 × 10(-3) M.

Self-organization at the interface and in aqueous solution of a cationic gemini surfactant from the dioctyl ester of cystine.

The cationic surfactant, dioctyl ester of cystine hydrochloride (DOEC), was characterized for interfacial adsorption and aggregation behavior in water. The cmc of DOEC was measured as 1.42±0.

1H NMR spectroscopic investigations on the conformation of amphiphilic aromatic amino acid derivatives in solution: effect of chemical architecture of amphiphiles and polarity of solvent medium.

In this study, the conformation of the amphiphilic lauryl esters of L-tyrosine (LET) and L-phenylalanine (LEP) in water and dimethyl sulfoxide is established. The alkyl chain protons of LEP in D(2)O appear at δ 1.010-1.

Adsorption and emulsification properties of amphiphilic poly(styrene-co-octadecyl maleamic acid salt) with comb-like architecture.

Amphiphilic poly(styrene-co-octadecyl maleamic acid salt) (PS-co-ODMAS) with a comb-like architecture was synthesized employing a heterophase aqueous polymerization reaction. The side-chain comonomer from octadecyl maleamic acid salt exhibited hydrogelation characteristics and provided conditions for a controlled polymerization reaction. PS-co-ODMAS polymers consisting of 5 and 10 mol% side-chain monomer showed a high molecular weight on the order of 10(6) and narrow polydispersity index at 1.

A facile methodology for the design of functionalized hollow silica spheres.

A new amino acid derived amphiphile, lauryl ester of tyrosine (LET) is shown to provide a facile methodology for the preparation of hollow silica spheres. In a previous study on the interface adsorption, it was shown that phenolic OH group in LET plays a key role in the formation and stabilization of close packed structures, typically at the oil/water interface. Drawing an analogy between the air/water and the oil/water interface, we detail here a procedure where air droplets are capped with LET aggregated structures, and in turn they are utilized as viable templates in the production of hollow silica spheres.

Amphiphilic lauryl ester derivatives from aromatic amino acids: significance of chemical architecture in aqueous aggregation properties.

Lauryl esters of L-tyrosine (LET) and L-phenylalanine (LEP) were, in a previous interface adsorption study, found to adopt very different interfacial conformations. The present study is an investigation of their aqueous aggregation properties with the goal of elucidating the effects of the presence in LET and absence in LEP of the phenolic OH group on their aqueous aggregate structures and micellar conformations of the surfactant monomers. The measured properties included aggregation numbers from time-resolved fluorescence quenching (TRFQ), interface hydration index and microviscosity by electron spin resonance (ESR), chemical shifts of (1)H resonance lines by NMR, and Krafft temperatures and enthalpies of structural transitions by differential scanning calorimetry (DSC).

Ionic polymeric amphiphiles with cholesterol mesogen: adsorption and organization characteristics at the air/water interface from Langmuir film balance studies.

Ionic polymeric amphiphiles consisting of cholesterol mesogen were investigated for the interfacial adsorption characteristics at the air/water interface using a Langmuir film balance with an aim to understand the influence of ionic segment from 2-acrylamido-2-methyl-1-propane sulfonic acid (AMPS) on the packing behavior of cholesterol at the interface. From surface pressure (pi)-area (A) isotherm characteristics, it is demonstrated that the homopolymer and the copolymer C consisting of 0.15 mol fraction CAB segments exhibit the most expanded structures contributing to surface area of about 84 A(2)/molecule.

Cholesterol mesogen containing water-soluble copolymers: design and organization behavior at different interfaces.

Cholesterol mesogen containing monomer, cholesteryl acrylamido butyrate (CAB) with the novel spacer group drawn from 4-amino butyric acid has been demonstrated to exhibit good reactivity with 2-acrylamido-2-methyl-1-propane sulfonic acid (AMPS) to yield copolymers with CAB content as high as 15 mol % hitherto not achieved. The spacer group is shown to provide the twin benefits of enhanced reactivity and solubility in water. The high pK(a) at > or =9.

Glycine derived polymerizable cosurfactant in the synthesis of functionalized poly(butyl acrylate) nanolatexes.

The approach of employing N-glycinylmaleamic acid (NGMA) as an efficient cosurfactant to provide microemulsion polymerization of butyl acrylate using a weight ratio of sodium dodecyl sulfate (SDS)/butyl acrylate (BA) at View Article and Find Full Text PDF

Octadecyl maleamic acid salt as a microreactor for its copolymerization reaction with butyl acrylate in aqueous medium.

The hydrogelator, octadecyl maleamic acid salt (ODMAS), has been shown to perform as a microreactor in copolymerization reaction with butyl acrylate in aqueous medium thereby providing functionalized latex. The evidence for occurrence of controlled polymerization reaction inside the microreactor is drawn from the composition and the polydispersity index of the copolymers. The copolymers generated under microreactor conditions or in other words, from emulsion phase provided by the hydrogelator exhibit significant incorporation of ODMAS with narrow polydispersity index.

A hydrogelator derived from polymerisable amphiphilic octadecyl maleamic acid and its potential as a reactor in aqueous copolymerisation reactions.

Octadecyl maleamic acid, a polymerisable surfactant, on coversion to its sodium salt, is shown to exhibit hydrogelation phenomenon. This hydrogelator, consisting of a lamellar structure is further shown to act as an organized reactor for controlled polymerisation reactions in order to generate copolymers with a narrow weight and size distribution.

Effect of N-glycinylmaleamic acid on microstructural characteristics and solubilization properties of sodium dodecyl sulfate micellar assemblies.

The cosurfactant activity of N-glycinylmaleamic acid (NGMA) in sodium dodecyl sulfate (SDS) micelles has been demonstrated. The complementary techniques of electron spin resonance (ESR) and fluorescence spectroscopy have been used to draw information on hydration index (H), microviscosity (eta), and aggregation number (N) of micellar assemblies. The estimate of the critical micelle concentration of SDS in the presence of NGMA suggests a synergistic effect of NGMA.