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The way the colloidal properties of surfactants respond to insertion of non-hydrocarbon functionalities within chains that are normally entirely hydrocarbon is described. On examination of monomolecular films of 10-hydroxysteraric acid, it was found that the hydroxyl and polar headgroup maintain contact with an aqueous subphase while the intervening chains form 'loops' above it.

Asterisks that comprise of six semigrid arms projecting from a benzene nucleus are synthesized with one, two, or three aromatic rings (connected by sulfur atoms) in each of the six arms. A phosphomonoester at the termini of each arm solubilized the asterisks in water.

Supramolecular systems--their successes, problems, and potential--are discussed with allusion to specific examples.

The article discusses the synthesis of the multiarmed and multicationic gemini surfactants that have pentaerythritol, dipentaerythritol and adamantane cores. Colloidal properties of the gemini in water have been examined.

A study was conducted to characterize the synthesis and reactivity of the 5-fluorouracil/cytarabine mutual anti-cancer drugs. The rate constants for hydrolysis of ester in 10 and in 1a was analyzed at various pH values. A mutual prodrug analog was also determined with aniline replacing the ara-C unit. Results indicated that the anticancer drugs can be released by enzymatic hydrolysis. Findings also showed that the prodrugs support two labile groups linking the drugs to the spacer.

Research was conducted to examine chelated lithium phenolates using NMR and X-ray spectrometry. Lithium phenolates with carbonyl functionalities in both the 2 and 6 positions enabled the metal to chelate to two oxygens. It was also observed through dynamic NMR that lithium has the ability to oscillate between the two chelating sites. Results indicate that lithium is static toward oscillation and that lithium phenolates form dimeric or tetrameric aggregates having a trigonal or a tetrahedral metal geometry.

The approaches for the synthesis of defective phospholipids is discussed. The methods either involve termination of the short fatty acid ends of the phospholipids, displacement of the bromine group with methoxide, acylation of the carboxylic acids, or insertion of the phosphatidylcholine group at the very end of the sequences of the complete dimeric skeleton. The schemes for the preparation of eight new phospholipids are presented.

Anionic liposomes are adsorbed onto the surface of spherical polymer particles bearing grafted linear cationic macromolecules. The size, shape, and encapsulation ability of the liposomes have remained unchanged upon adsorption, which have provided immobilized self-organizing containers that have potential applications in the biomedical field.

Efforts to correct errors in a published scientific article were met with defensive evasion on the part of editors and constituted a failure of the peer-review system. Senior editor Allen J. Bard and associate editor Richard L. Schowen of the Journal of the American Chemical Society dismissed efforts to point out egregious errors in a pair of articles co-authored by Ronald Breslow. The interests of science and of the public which funds it require that editors permit rebuttals by those who have the time and interest to read an article carefully.

A study was conducted to re-evaluate the molecular areas of soluble films at the air/water interface derived by the Gibbs equation which are too large to account for the abrupt surface tension decline. The surface tension plot leveled off due to saturation proved that the interface in the Gibbs region is not saturated and hundreds of published molecular areas obtained by the Gibbs approach should be reconsidered.

The synthesis of a compound that contains four functional groups in close quarters is described including the challenges faced during the synthesis. Students learn the facets of synthetic organic chemistry that are ofen left out in published syntheses.

Conductivity and diffusion NMR are used to measure the critical micelle concentration (CMC) values from dodecyltrimethylammonium bromide (DTAB)/trianion mixtures and gain insigth into the sharp break observed in surface-tension 'CMC plots'. The unusual discrepancy observed between the CMC based on surface tension and on the two 'bulk' methods are attributed to saturation of the air/water interface by a DTAB/trianion complex far below the concentration at which the micelles form.

The preparation and studies of a series of polybetaines ([PB.sub.n]) having cationic and anionic units covalently linked by short -[(C[H.sub.2]).sub.n]- spacer is reported. The results revealed that the length of the -[(C[H.sub.2]).sub.n]- spacer in betaine units have a significant effect on the ability of polybetaines to interact with anionic liposomes and to induce structural rearrangement within the liposomal membrane.

The studies of the amphiphile diketopiperazine ring inserted between a chain and an ionic headgroup is reported. The results from the characterization of properties of ionic headgroup provide insight into monolayer films at the air/water interface where the diketopiperazine have a profound effect on the compression isotherms.

Solution and solid-phase synthesis of a cyanine dye conjugated to polystyrene beads are described. The spectroscopic properties of conjugated dye exposed to apolar media where ion pairing and reduced delocalization is possible are examined.

The NMR diffusometry and other techniques are employed to study the aggregation and hydration of short-chain nonionic surfactants containing amide bonds. The presence of the amide bonds in the surfactants is shown to lead to higher surface hydration in the compounds.

The self-assembly of penta-segmentation organic molecules of the general structure A-B-A-B-A or B-A-B-A-B, where A is a hydrophilic polyether and B is a hydrophobic carbon chain, is examined. The results have shown that the segmentation can have a dramatic effect upon solute properties, including solubility, propensity to self-assemble, aggregation number, and cooperativity.

[super 23]Na NMR evidence is provided showing that sodium ions can locate itself inside the actual phospholipid bilayer. A vesicular membrane composed of a conventional phospholipid (1-palmitoyl-2-oleoyl phosphatidylcholine or POPC) admixed with a lesser amount of a 'designer' phospholipid that possesses ester groups along its normally all-hydrocarbon chains is used to show that the ester groups create membrane 'pockets' in which sodium ions reside.

A kinetic approach is described to investigate chain exposure of self-assembly interiors to external elements, in which hydration or chain/water contact is a key feature. A methylene in a hydrophobic thio-surfactant chain is replaced by a sulfur atom, and NMR resolutions are used to study the oxidation rates of the sulfur labels that can be used to assess chain exposure to the external medium in self-assemblies and polymeric systems.

A study on ice formation from saline at concentrations near that of seawater, by cryo-etch high-resolution scanning electron microscopy, is presented. The study reveals some surprising morphologies.

Study of 10 asymmetric gemini surfactants that self-assemble into vesicles, which, in turn, self-assemble into gels is presented. The strings of vesicles create a complex network that rigidifies the water.

It is found that giant vesicles lend themselves to quantitative analysis by the parallax method. Despite the effect of a high radius of curvature upon chain disorder, small vesicles are found to be identical.

A remarkable parallel between jointing in geological formations and jointing in vitreous ice containing a surfactant when observed by cryo- high resolution scanning electron microscopy (cryo- HRSEM) is described. The method can be particularly useful and non invasive for discovering new modes of self assembly in water.

A synthesized non-steroidal facial amphiphile that possesses two water-solubilizing sulfates on one face and a rigid wall of hydrophobicity on the other is presented. The larger area/molecule of non-steroidal facial amphiphile tends to adversely affect its surface activity and the rigidity of the structure might impair the packing density at the air/water interface.

The shell phase forms when certain picolinates are subjected to energy input while exposed to a water/toluene mixture. A shell, about 600 angstrom thick and containing the picolinate and toluene, surround the water droplets that are always produced during the mixing process.

The synthesis of Giant vesicles (GVs) has been described. Zein's (Protein) stability and hydrophobicity make it an ideal subject for studying membrane-bound proteins in GV biolayers.

When a giant vesicle composed of POPC (rendered anionic with 5 mol % POPG) touches a giant POPC vesicle (rendered cationic with 5 mol % of DDAB), an electrostatically driven bilayer adhesion is visible under the light microscope. Although similar fusion did take place in the study, close observation also revealed a reversal of the adhesion process caused by internal membrane dislocations.

It is concluded that poly-L-lysine, despite its polycationic character, can pass through a lipid bilayer when complexed with an anionic lipid present in the vesicle wall. Entry of poly-L-lysine via endocytosis seems unlikely because no corresponding changes in morphology were observed with the giant vesicles.

The information-content of cryo-etch-HRSEM pictorial but distinctive in nature, is illustrated with gel and coacervate systems formed from a new series of Gemini surfactants. Cryo-etch-HRSEM pictures reveal a rough surface consistent with a colony of spherical vesicles projecting from the ice.

A group of 42 zwitterionic gemini surfactants were synthesized, purified and examined using electron and light microscopy, calorimetry and dynamic light scattering.

Polymers that serve as elimination catalysts in the dehydration of a beta-hydroxy ketone have been developed. These combinatorial polymers, which exhibit a slow induction as if 'learning' how to promote the elimination reaction, show that a previously described polymer which catalyzes a phosphate hydrolysis was not a rare occurrence. Results affirm that combinatorial polymeric catalysis is an interesting field that merits further study.

Amino acid derivatives that rigidify water at submillimolar concentrations were studied.