The Langmuir-Blodgett (LB) multilayers of the manganese salt of 10, 12-pentacosadiynoic acid (12-8 ADA) were prepared. The polymerization behavior by UV-irradiation was similar to that of well known 12-8 ADA multilayers as the cadmium salt. But the polymerization and the phase transition from a blue form to a red form during polymerization were accelerated about 4 times and the absorption of a final polymer was twice as large compared with the cadmium salt (Fig.2). These observations indicated that the side chain was much more flexible in a LB-multilayer of 12-8 ADA as the manganese salt than the cadmium salt. From X-ray diffraction studies, changes of interlayer spacings during the polymerization process were measured. Marginal decrease was observed for the manganese salt with approximately=0.6%, but significant decrease was observed for the cadmium salt with approximately 8% (Table 1). The results indicated more favorable packing in the 12-8 ADA multilayer for the polymerization as a manganese salt and supported the smooth polymerization process. Polarizing micrographs indicated large domains of a maximum size of 3 x 1 mm and crystallographic register between layers were formed in polymeric LB-multilayers of 12-8 ADA as the manganese salt (Figs.6-8).

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A new amphiphile with a sodium sulfonate group and two polymerizable alkyl chains, sodium 1, 2-his [16-(acryloyloxy)hexadecyloxycarbonyl]ethanesulfonate -(2AC₁₆SNa), was synthesized. 2AC₁₆SNa monolayer on the pure water surface was built-up on the polymeric substrate film (polystyrene or polyethylene) successively by applying Langmuir-Blodgett method by use of oleic acid as piston oil. The monolayer was not built-up on the polymeric substrate when the substrate moved down into the water but was built-up when it moved up from the water. From the area variation of the 2AC₁₆SNa monolayer on the water surface during the built-up process, the film must be btilit-up as a Z-membrane. However, it became apparent from X-ray study that the finally obtained built-up film was Y-membrane. 2AC₁₆SNa monomers in the built-up film were polymerized by UV-irradiation. The X-ray pattern of the polymerized 2AC₁₆SNa built-up film was similar to that of the monomer film. This result indicates that polymerization proceeds, maintaining highly oriented bimolecular structure. When UV-irradiation was carried out in water, the surface of the polymerized built-up film was very hydrophillic. This indicates that 'sodium sulfonate groups are highly oriented on the built-up film surface. Blood compatibility of the polymerized built-up film was evaluated from the interaction with human blood platelets. The number of adhered and deformed platelets on the built-up film surface was less than that of the polyethylene surface which was used as a substrate, and almost comparable with that of the poly(urethane-urea) surface which shows relatively excellent blood compatibility.

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N-Octadecylmethacrylarnide (ODMA) monomer spread from a benzene solution on a water surface forms a stable solid condensed monolayer and the limiting molecular occupied area was found to be 0.25 nm². The monolayer could be deposited on solid supports, such as silicon wafer, quartz slide, and CaF₂ plate, successively by the Langmuir-Blodgett technique with transfer ratios of about 1, and the Y type LB film was obtained. The orientation structure of ODMA in LB film was estimated by the comparison of the. FT-IR spectra between in LB film and in KBr pellet. The polymerization of ODMA in LB film by ultraviolet (UV) irradiation was ascertained by the decrease of the absorption due to double bond in electronic spectra and FT-IR spectra. The polymerized LB films were uniform thin films and were not dissolved in ethanol and acetonitrile solvents where the monomer LB film can be dissolved. On UV irradiation through a deep UV mask on the LB film and then a rinse by ethanol, the fine negative resist patterns due to the polymerized ODMA LB film could be drawn, showing that this LB film can be used as an UV-sensitive negative resist.

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It was found that the Langmuir-Blodgett films (LB films) of polyimides deposited on a substrate had a fair ' degree of orientation to the transfer direction of the substrate. The dichroic ratio of the absorbance of the LB films parallel to the transfer direction to that perpendicular to the direction in the polarized UV spectra increased with increasing the surface pressure for deposition, whereas it was almost independent on the deposition speed and the chemical structure of polyamic acids. it was observed that the polyimide LB films made liquid crystals align orderly without rubbing treatment of the LB films. The best results were obtained when 5 layers of the LB film were used.

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Morphology of the conducting Langmuir-Blodgett (LB) films was studied by means of polarizing microscopy and scanning electron microscopy. The LB film of N-docosylpyridinium (TCNQ)₂ complex consists of fine crystallites, and the surface is rather sm ooth. In contrast, the LB film of TMTTF octadecyl TCNQ complex contains rod-like crystallites, some of which lie on the film surface. It, is suggested that higher conductivities will be obtained by controlling the macroscopic structures of the films.

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It was found that the long chair alkylamine salts [ 3 ] of poly(amide-amic acid) derived from 4-(chloroforrnyl)phthalic anhydride and aromatic diamines formed monolayer films at the air-water interface and that the monolayer films were successfully deposited onto the appropriate substrata.
The multilaye r films of [3 ], were converted into multilayer films of poly(amide-imide)[4 ] by chemical imidation using acetic anhydride and pyridine. Good relationship was found between the film thickness and number of layers of [ 4]. The monolayer thickness of 4D was estimated to be 0.43-O.55 nm by means of ellipsometry.

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We have developed experimental approaches for construction of protocellular structures under simulated primitive earth conditions and have studied their formation and characteristics. Three kinds of protein envelopes were constructed in situ from amino acids under simulated primitive earth conditions such as a fresh water tide ppol, a warm sea, and a submarine hydrothermal vent. One protein envelope was formed from a mixture of amino acid amides at 80°C using multiple hydration-dehydration cycles. Marigranules, protein envelope structures, were formed from the mixtures of glycine and acidic, basic and aromatic amino acids at 105°C in a modified sea medium enriched with essential transition elements., Thermostable microspheres were also formed from a mixture of glycine, alanine, valine, and asparitic acid at 250°C and above. The microspheres were not formed at lower temperatures and consisted of silicates and peptide-like plymers containing imide bonds and amino acid residues enriched in valine. Amphiphilic proteins with molecular weight of 2000 were necessary for the formation of the protein envelopes.

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One step size control of large multilamellar liposomes (LMLV) was accomplished by the reconstitution of liposomes through polycarbonate filter with homogeneous pores of 0.6 μm. Pressure difference across the filter was, at most, 1 atom. Size control of LMLV composed of phosphatidylcholine was well-completed when the membrane was in liquid crystalline state. Addition of cholesterol gave negative effects on the reconstitution of membrane in liquid crystalline state, while cholesterol improved the size control of phosphatidylcholine membrane in gel state. Various hydrophilic compounds, dyes and proteins, were encapsulated in liposomes by the freeze-thawing method. Size control of the resultant LMLV by the reconstitution with polycarbonate filter did not cause any encapsulated materials leakages. Therefore, it was presumed that the reconstitution of LMLV to the smaller liposomes was taken place by tearing-off of liquid crystalline sections of LMLV membrane in the filter pore.

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To investigate bilayer structures of amphiphilic compounds based on X-ray diffraction data, the method of analysis was designed and programmed for the computer calculation. In order to verify this program, it was applied to the analyses of wholly synthetic amphiphiles whose bilayer structures were determined precisely by X-ray single crystal analyses. The result shows that the program is very effective for investigating molecular aggregation states, especially when there are enough number of reflections which have information about a repeating period of a bimolecular layer. Since many amphiphilic compounds have only small number of flexible parts of their molecular conformation in a gel state, the important parameters for the molecular packing in a bilayer structure are not those regarding the molecular conformation, but the inclination angle of the molecule to the bilayer surface and the translation of the molecule along the direction normal to the surface. The agreement between calculated and observed structure amplitudes is very sensitive to these two parameters.
This program is applicable to the structure analyses of crystalline powder, casting films and Langmuir-Blodgett films of amphiphilic compounds, but cannot be applied to those of X- and Z- built-up films because of their non-centrosymmetric structures.

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The circular dichroism (CD) active phospholipid having azobenzene moiety in a close proximity to the chiral, carbon, [1], was used for the study of lipid-lipid and lipid-protein interaction in liposome system.
The large CD enhan cement of the chiral bilayer arised from the interaction of spatially fixed chromophores even in the fluid state (50°C) and this CD enhancement was remarkably reduced by the presence of a small amount of cis-azobenzene chromophore (Fig.1). After irradiation of the liposome solution at 5°C, the amount of three isomers of phospholipid, trans, trans-, trans, cis- and cis, cis- were investigated by HPLC. Observed cis; cis- content was much larger than that calculated from trans, cis- to trans, trans- ratio (Table 1), suggesting that one cis-azobenzene chromophore changes the conformation of trans-azobenzene chromophores to make their isomerization easy and this effect is preferential on trans-azobenzene in chromophore the same molecule.
Delipidated bacteriorhodop sin purified from purple membrane of H. halobium was reconstituted with the CD active phospholipid [1], The observed CD spectra in the 450-700 nm region characteristic of bacteriorhodopsin showed the temperature dependence characterized by midpoint at ca.45°C and this spectral change showed the disaggregation of bacteriorhodopsin trimer to monomer. The CD spectra in the 250-400 nm region characteristic of the azo chromophore of phospholipid exhibited a remarkable temperature dependence synchronized with the disaggregation of bacteriorhodopsin, suggesting that a large proportion of the phospholipid is present as boundary lipid (Figs.2, 3). This paper is dedicated to professor I w ao Tabushi who deceased on Mar.22, 1987, with my great respect for him.

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Electrochemically controlled adsorption of an enzyme to solid electrode surface was applied to form functional thin protein membranes. Glucose oxidase (GOD) was adsorbed on a platinum electrode surface at a controlled potential in an aqueous solution. Adsorbed GOD was quantitatively analized by the fluorescent method. The GOD-adsorbed electrode was assayed for its enzyme activity by colorimetry. It was found that GOD adsorption and the enzyme activity of the GOD-deposited electrode were controllable by the adsorption potential. Thin protein molecular membranes were formed on the platinum surface in the surface coverage ranging from 3 to 4. Enzyme activity of a GOD-adsorbed electrode also depended on pH of the electrolyte solution for electroadsorption and reached optimum at pH 3. Furthermore, GOD-electrochemically deposited platinum electrode was applied to an amperometric sensor for glucose. The sensor showed rapid response (2s).

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A polyvinylbutyral (PVB) membrane was applied to the surface of a silicon nitride which is the gate insulator of the ISFET (Ion Sensitive Field Effect, Transistor). The membrane exhibited good adhesive properties and was used for urease immobililation. The water content of the membrane was 27.6% with- a thickness of 23 μm. The surface structure of the membrane was observed by scanning electron microscopy, which revealed a regular porous microfilter arrangement with a mean pore diameter of 0.25 μm. Immobilized urease activity in this membrane was approximately 20% higher than when a urease-triacetylcellulose membrane was used.
H⁺-ATPase in biologic al membrane is known as an enzyme to produce or hydrolyze, ATP. The ATP-FET sensor was constructed using immobilized H⁺-ATPase' PVB m embrane. A linear relationship was obtained between the initial rate of change of the 'differential gate output voltage and the logarithm of the ATP concentration over the range 0.2-1.0mmol⋅dm^-3- ATP. The optimum pH was 9.0 at 40°C. The selectivity was good. The ATP sensing system exhibited a response to 1 mmol⋅dm^-3 ATP for at least two weeks.
Human serum albumin has the minus charge at pH 7.0, The immuno-FET sensor was constructed. Anti-human serum albumin was immobilized on the, ISFET using PVB membrane. Binding of the human serum albumin to, , the anti-human serum albumin caused a decrease in the differential gate output voltage of the system. This response is attributed to the minus charge of human serum albumin. A linear relationship was obtained in the range 0.01-1 mg⋅ml^-1

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2-(Methacryloyloxy)ethyl 4-methoxyphenyl hydrogenphosphate (CH₃O-OH monomer), which is a new phosphate monomer with hydrophobic and hydrophilic groups, is effective to give adhesion to tooth substrate partly for its biocompatible nature. The bond strength between dentin treated with 10% citric acid and 3% iron (III) chloride (10-3 solution) and CH₃O-OH monomer/MMA-TBB resin was 17 MPa. Using a bonding agent containing CH₃O-OH monomer and BPO-sulfinic acid initiator, the bond strength between dentin treated with 10-3 solution and selfcured resin was 10 MPa, and that was 13 MPa in case of dentin treated with 0.3 mol⋅dm^-3 EIDTA. The monomer inter-penetrated into dentin and polymerized was confirmed by SEM and TEM observation of the bonded tissue. A HCl insoluble dentin layer modified, by the interpenetration in the subsurface of tissue was observed. The layer on dentin surface is a resin reinforced dentin and has better resistance against decalcification than the original. The layer is a hybrid of natural tissues with biocompatible artificial materials.

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