During the treatment of viral or bacterial infections, it is important to evaluate any resistance to the therapeutic agents used. An amino acid substitution arising from a single base mutation in a particular gene often causes drug resistance in pathogens. Therefore, molecular tools that discriminate a single base mismatch in the target sequence are required for achieving therapeutic success. Here, we synthesized peptide nucleic acids (PNAs) derivatized with tolane via an amide linkage at the N-terminus and succeeded in improving the sequence specificity, even with a mismatched base pair located near the terminal region of the duplex. We assessed the sequence specificities of the tolane-PNAs for single-strand DNA and RNA by UV-melting temperature analysis, thermodynamic analysis, an in silico conformational search, and a gel mobility shift assay. As a result, all of the PNA-tolane derivatives stabilized duplex formation to the matched target sequence without inducing mismatch target binding. Among the different PNA-tolane derivatives, PNA that was modified with a naphthyl-type tolane could efficiently discriminate a mismatched base pair and be utilized for the detection of resistance to neuraminidase inhibitors of the influenza A/H1N1 virus. Therefore, our molecular tool can be used to discriminate single nucleotide polymorphisms that are related to drug resistance in pathogens.

Sialyllactose (SL)-modified trimer DNAs with a similar SL presentation as their binding sites on influenza virus hemagglutinin (HA) trimer were designed and synthesized. These trimer DNAs showed high affinity for various influenza viruses, including A/Puerto Rico/08/34 (H1N1), A/Beijing/262/95 (H1N1), A/Yokohama/77/2008 (H1N1), and A/Panama/2007/99 (H3N2). Thus, presentation of SL residues on three vertexes of the scaffold as well as sialic acid binding sites on the HA trimer regardless of a tri-branched or triangular scaffold are important for high affinity for influenza viruses. These compounds have the potential for use in detection and as inhibitors of a broad spectrum of influenza viruses.

Natural sialic acid-modified compounds are capable of targeting influenza virus hemagglutinin (HA). However, these compounds have limited inhibitory effect because natural O-glycoside bond in these compounds are prone to be cleaved by neuraminidase (NA) on the surface of viruses. In this study, we synthesized NA-resistant sialoside that included unnatural S-glycoside bonds and modified this sialoside on a three-way junction (3WJ) DNA to display complementary distribution to its binding sites on a HA trimer. This S-glycoside-containing sialoside-modified 3WJ DNA showed certain NA resistance and maintained high binding affinity. Importantly, our observations showed that substituting natural O-glycoside with unnatural S-glycoside did not affect the binding affinity of the sialoside-modified 3WJ DNA for viruses. Thus, this study is an important step forward in the development of NA-resistant sialoside derivatives for more effective detection and inhibition of infection by a broad spectrum of viruses.

Sialic acid present on the cell surface is recognized by hemagglutinin (HA) on the influenza virus in the first step of infection. Therefore, a compound that can efficiently interfere with the interaction between sialic acid and HA might inhibit infection and allow detection of the influenza virus. We focused on the spatial arrangement of sialic acid binding sites on HA and dev

Novel trigonal DNA-carbohydrate conjugates were prepared and evaluated to explore efficient carbohydrate-lectin interactions. Carbohydrate-modified oligonucleotides were enzymatically prepared, then hybridized to form 3-way junction DNAs. The thermal stabilities of the junctions were assessed by UV melting analysis and formation of constructs was confirmed by gel electrophoresis. Fluorescence titration assays revealed that the trigonal DNA-carbohydrate conjugates exhibit high affinity to lectins depending on the distribution of carbohydrates presented in each arm. These results suggest that self-assembled 3-way DNA architectures could offer a useful platform for controlling the spatial distribution of carbohydrates on conjugates and achieving more efficient molecular recognition.

Addition of co-solvents such as tetrahydrofuran resulted in a great improvement of the enantioselectivity of lipase-catalyzed hydrolysis of butyl 2-(4- substituted phenoxy)propanoates in an aqueous buffer solution. On the other hand, lipase lyophilized from an aqueous solution containing the co-solvents catalyzed highly enantioselective esterification of 2-(4-substituted phenoxy)propionic acids, 2-(4-isobutylphenyl)propionic acid (ibuprofen), and 2-(6-methoxy-2-naphthyl)propionic acid (naproxen) in an organic solvent. An increase in the E value up to two orders of magnitude was observed for some substrates. The origin of the enantioselectivity enhancement caused by the co-solvent addition was mainly attributed to a significant deceleration in the initial reaction rate for the incorrectly binding enantiomer, as compared with that for the correctly binding enantiomer. From the results of FT-IR, CD, and ESR spectra, the co-solvent addition was also found to bring about a partial destruction of the tertiary structure of lipase.

Novel deoxyribonucleotide triphosphates bearing maltose or lactose groups were synthesized as substrates for DNA polymerase. The incorporation efficiencies of these modified substrates were investigated in both primer extension reactions and PCR. The stability and conformation of saccharide-modified dsDNAs were assessed by UV absorbance melting experiments and CD analysis. Enzymatic incorporation of saccharide-modified substrates can be used for the efficient production of saccharide-modified DNAs.

We propose a simple and a powerful method to enhance the enantioselectivity for lipase-catalysed transformations in organic solvents by an addition of metal ion-containing water to the reaction mixture. In this paper, various metal ions such as LiCl or MgCl2 are tested to improve the enantioselectivity for the model reactions. The enantioselectivities obtained are dramatically enhanced, the E values of which are about 100-fold as compared with the ordinary conditions without a metal ion, for example, E = 200 by addition of LiCl. Furthermore, lowering the reaction temperature led to an almost perfect enantioselectivity of lipase in the presence of a metal ion, for example, E = 1,300 by addition of LiCl. Also, a mechanism for the drastic enhancement by metal ions is discussed briefly on the basis of the EPR spectroscopic study and the initial rate for each enantiomer of the substrate.

The addition of sodium dodecyl sulfate (SDS) resulted in a dramatic improvement of the enantioselectivity of the lipase-catalyzed hydrolysis of racemic butyl 2-(4-substituted phenoxy)propanoates, racemic butyl 2-(4-isobutylphenyl)propanoate, and racemic butyl 2-(6-methoxy-2-naphthyl) propanoate in an aqueous buffer solution. An increase in the E value by up to two orders of magnitude was observed for some esters. As to the effects of SDS on the structure of a lipase, FT-IR and fluorescence measurements suggest some conformational change and/or an increase of the flexibility of the lipase, although the native secondary structure of the lipase is held even in the presence of 100 mM SDS. The origin of the enantioselectivity enhancement brought about by the addition of SDS is briefly discussed on the basis of the values of the initial rates obtained for each enantiomer of the substrate. © 2005 Elsevier Ltd. All rights reserved.

The lyophilization of lipase from aqueous enzyme solution containing ionic compounds such as disodium hydrogenphosphate resulted in a dramatic improvement of its enantioselectivity for esterification in organic solvents, compared with the ionic compound-free lipase. The enantioselectivity of the ionic compound-coated lipase was found to be fairly sensitive to the change of the solvents. Copyright © 2005 The Chemical Society of Japan.

For lipase-catalyzed reactions of 2-(4-substitued phenoxy)propionic acids with alcohols in organic solvents containing a small amount of water, the increase of the lipase flexibility brought about by addition of water is found to be favorable for the induced-fit motion of the lipase for the correctly binding enantiomer of the substrate used, thus resulting in the improvement of the lipase enantioselectivity. In particular, for the reaction of the substrate with rich π electron density on its aromatic ring, the enantioselectivity was much more sensitive to the change of the lipase flexibility. Thus, in the induced fit motion, the CH⋯π association between amino acids side chains around the lipase's active site and the aromatic ring of the correctly binding enantiomer is assumed to accelerate the accommodation of the substrate into the lipase's active site and the stabilization of the complex between the enzyme and the substrate. This assumption is also supported by a discussion based on the value of the Michaelis constant obtained. Furthermore, on the basis of a model concerning the acyl-enzyme structure for the incorrectly binding enantiomer, the long alkyl chain alcohols as a nucleophile are found to improve the lipase enantioselectivity markedly.

Semi-purified lipases from Candida rugosa, Pseudomonas cepacia and Alcaligenes sp. were chemically modified with a wide range of hydrophobic groups such as benzyloxycarbonyl, p-nitrobenzyloxycarbonyl, p-methoxybenzyloxycarbonyl, t-butoxycarbonyl, lauroyl and acetyl moieties. The Candida rugosa lipase MY modified with the benzyloxycarbonyl group (modification ratio = 84%) brought about a 15-fold increase in enantioselectivity (E value) towards the hydrolysis of racemic butyl 2-(4-ethylphenoxy)propionate in an aqueous buffer solution, although the enzymatic activity was decreased. The origin of the enantioselectivity enhancement by chemical modification of the lipase is attributed to a significant deceleration in the initial reaction rate for the incorrectly binding enantiomer.

The behavior of the enantioselectivity of Candida rugosa lipase was investigated in the esterification of 2-(4-substituted phenoxy)propionic acids with 1-butanol in aliphatic, aromatic, and ethereal solvents. The observed enantioselectivity (E value) was greatly affected by the solvent nature. Two key solvent characteristics, dielectric constant (e) and hydrophobicity (log P), failed to explain the solvent effects on the E value. On the other hand, the variation of the E value was found to be successfully correlated with the lipase flexibility brought about by the solvent effects, the flexibility of which was estimated by the ESR measurements of the spin-labeled lipase. Although organic chemists should often undertake a solvent screening step in the biocatalytic asymmetric resolutions, the obtained correlation will provide a useful guide in the solvent optimization step.

The chemical modification of lipase with the hydrophobic group such as Z (benzyloxycarbonyl) or Z(NO2) (p-nitro-Z) is found to bring about a marked improvement of the enantioselectivity in isopropyl ether and an inversion of the solvent effects on the enantioselectivity.

The enantioselectivity of the lipase-catalyzed esterification of 2-(4-substituted phenoxy)propanoic acids was found to be dramatically enhanced by addition of aqueous sodium dodecyl sulfate (SDS) as a new type of additive to the reaction medium, isopropyl ether. The origin of the enhanced enantiomeric differentiation may be attributed to the increased conformational flexibility of lipase triggered by the SDS action, the flexibility of which can be estimated from the changes in the ESR spectra observed for the mobility of a spin label bound to its active-site.

We applied a highly sensitive quartz-crystal microbalance as a device of dsDNA in vitro selection. When poly(L-glutamine)-immobilized QCM was employed, both the selection and evaluation processes could be monitored in situ as mass changes, and the dsDNAs having the continuous sequences of 3-5 AT base-pairs were selected after the 4(th) cycle from a random dsDNA pool.

Nonnatural DNA polymerase substrates which contain many kinds of modified functional groups are synthesized. The C-5 position of dUTP was modified by amino acid, saccharide. These compounds were incorporated on a DNA double strand using E. Coli DNA polymerase. This nonnatural DNA library contains a larger diversity than native DNA or RNA and has a higher chemical stability than RNA. This library will be useful for in vitro selection study, combinatorial chemistry, and the preparation of supramolecular structures.

A highly sensitive 27-MHz quartz-crystal microbalance, on which a 10-30-mer oligonucleotide was immobilized as a probe molecule, was employed to detect hybridization of complementary oligonucleotides in aqueous solution, From frequency decreases (mass increases due to the hybridization) with passage of time, kinetic parameters such as association constants (R-a) and binding and dissociation rate constants (k(1) and k(-1)) could be obtained, as well as binding (hybridization) amount at the nanogram level (Delta m). Kinetic studies were carried out by changing various parameters: (i) the immobilization method of a probe oligonucleotide on Au electrode, (ii) number of mismatching bases in sequences of target oligonucleotides, (iii) length of both probe and target oligonucleotides, (iv) hybridization temperature, and (v) ionic strength in solution. The obtained results were compared with those obtained by a surface plasmon resonance method using a BIAcore system.

Complementary molecular recognition in the gas phase onto self-assembled monolayers bearing thymine or adenine bases as terminal groups was studied by using a highly sensitive 63 MHz quartz-crystal microbalance. Association constants (Ka), binding and dissociation rate constants (k1 and k-1), and binding amount in nanogram level (Δm) could be obtained from time coarses of frequency decrease (mass increase) at various gaseous guest concentrations. Kinetic parameters were corrected to avoid the effect of different adsorption ability of guest molecules. Binding of 2-aminopyridine (an adenine model) onto a thymine monolayer showed the 50-100 times larger binding constant than that of a noncomplementary guest molecule, γ-butyrolactam. On the other hand, an adenine monolayer preferentially bound the thymine model of γ-butyrolactam over 2-aminopyridine, the adenine model. When a simple hydrocarbon monolayer of 1-decanethiol was used, all of these guest molecules were hardly bound. The selectivity between complementary and noncomplementary nucleobase pairs observed in the gas/thin film surface was comparable to the selectivity seen in organic solvents. The formation energy of hydrogen bonding obtained from Ka values in the gas/thin film surface was consistent with that calculated by molecular mechanics as in a vacuum. Ka values of the guest molecules were dependent on the nucleobase content in the mixed monolayer of nucleobase and alkyl chains.

Differences of hepatocyte attachment and morphology of adherent cells between anti-asialoglycoprotein receptors (α-ASGPR) and poly (N-p- vinylbenzyl-O-β-D-galactopyranosyl-[1 → 4]-D-gluconamide) (PVLA) coated surfaces were investigated for a new application of antibody as an extracellular matrix. It was found that about 70% of mouse primary hepatocytes attached onto the α-ASGPR-coated plates within 2 h. The hepatocyte attachment was inhibited with pretreatment of soluble α-ASGPR or PVLA. Also, the number of the adherent hepatocytes drastically decreased if treated with papain as an endopeptidase but not with EDTA. This was in contrast with the hepatocytes attached onto PVLA-coated plates, suggesting that cell attachment through specific interaction between the ASGPR and α- ASGPR was Ca2+ ions-independent. The adherent hepatocytes exhibited quite different morphology with the coating density of the α-ASGPR. The morphology of adherent hepatocytes for a high coating density (10 μg/ml) was observed as spherical shapes whereas the morphology of hepatocytes for a low coating density (0.1 μg/ml) was observed as fiat ones. Furthermore, when cellular function was examined for hepatocytes with different morphology, it was found that DNA synthesis of fiat hepatocytes for the lower coating densities was higher than that of round hepatocytes for the higher coating densities in the presence of epidermal growth factor.

The complementary guest binding process onto the cyanurate lipid 1 monolayer at the air-water interface was observed by using a highly sensitive 27 MHz quartz-crystal microbalance (QCM), which was attached horizontally on the monolayer from the air phase. Binding amount (Δm), association constants (Ka), as well as binding and dissociation rate constants (k1 and k-1) could be obtained from time courses of the frequency decrease (mass increase) of the QCM. A highly sensitive 27 MHz QCM was used to detect small mass changes of Langmuir adsorption of small guest molecules instead of our conventional 9 MHz QCM. Guests such as 2,4,6-triaminopyrimidine (A) possessing three complementary hydrogen bonding sites were selectively bound to the monolayer 1 showing a 1:2 host-guest binding ratio, k1 = 2.8 M-1 s-1, k-1 = 7.2 × 10-4 s-1, and Ka = 3900 M-1. The Ka value was consistent with that obtained by NMR spectra in bulk CDCl3. Guest molecules of A hardly bound to monolayers 2-4 with -NH2, -CONH2, and -OH head groups. Binding constants of guest molecules to the monolayer 1 were of the following order: 2,4,6-triaminopyrimidine (A) > 2,6-diaminopyridine (B) possessing three hydrogen bonds > 2-aminopyridine (C) forming two hydrogen bonds > pyridine (D) with only one hydrogen bond ≈barbituric acid (E) having no complementary hydrogen binding sites. The obtained binding kinetics at the water interface were compared with molecular mechanics calculations of binding energy in vacuum.

Self-assembled monolayers of alkanethiols having functional groups (HS(CH2)10X; X = -H, -COOH, -CONH2, -NH2) were immobilized on an Au electrode of a quartz-crystal microbalance (QCM), and binding kinetics of acetic acid molecules from the gas phase were studied from time courses of frequency decreases (mass increases) of the QCM. A highly sensitive, 63 MHz overtone frequency of a conventional 9 MHz AT-cut QCM was developed to detect monolayer adsorption of small molecules such as acetic acid. Acetic acid molecules are adsorbed onto the -CONH2 membrane as a Langmuir-type monolayer; however, they tend to be adsorbed as multilayers onto the -COOH and -NH2 membranes. Acetic acid was hardly adsorbed onto the simple alkane membrane (-H membrane). The binding ability of the -COOH membrane to acetic acid molecules was reduced compared with that of the -CONH2 membrane due to the intramembranous hydrogen bond in the former.

A self-assembled monolayer of alkanethiols having functional groups (HS-(CH2) 10-X; X =-H, -COOH, -CONH2) was immobilized on Au electrodes of a quartz-crystal microbalance (QCM), and the adsorption behavior of gaseous organic molecules, such as aliphatic acids, amines, alcohols, and alkanes, was observed from frequency decreases (mass increases) of the QCM plate in gas-phase. We used a supersensitive, seventh overtone frequency of a 9 MHz AT-cut QCM (63 MHz) in order to detect a monolayer adsorption of small organic molecules. Association constant (Ka), adsorption (k1) and desorption rate constants (k-1) could be obtained from curve fitting of time courses of frequency changes (mass changes). All organic molecules hardly adsorbed onto the alkane (X = -H) membrane. To the -CONH2 membrane, only acetic acid can be selectively adsorbed compared with the -H membrane, but not caproic and nonanoic acids, which explains that hydrogen-bond interactions are important but hydrophobic interactions are not. To the -COOH membrane, both acetic acid and ethylenediamine can largely adsorb compared with the -H membrane, but not monoamines. The adsorption of ethylenediamine can be explained by acid-base interactions.

Self-assembled monolayers of alkanethiols having functional groups (HS-(CH2)10-X, X = -H, -COOH, -CONH2, -NH2, thymine and adenine bases) were immobilized on the Au electrode of a quartz-crystal microbalance (QCM), and binding kinetics of guest molecules from the gas phase were studied from time courses of frequency decreases (mass increases) of the QCM. A highly sensitive, 63-MHz overtone frequency of a conventional 9-MHz at AT-cut QCM was developed to detect monolayer adsorption of small molecules. When acetic acid was employed as guest molecules, it adsorbed onto the -CONH2 membrane as a Langmuir-type monolayer and adsorbed as multilayers onto the -COOH and -NH2 membranes, but hardly adsorbed onto the simple alkane membrane (-H membrane). When self-assembled monolayers bearing a thymine or adenine base as a terminal group were employed, selective binding processes of complementary guest molecules were observed: 2-aminopyridine (an adenine model) and γ-butyrolactam (a thymine model) selectively bound to the thyamine and adenine monolayers, respectively.

Specific binding and dissociation processes of concanavalin A (Con A) to a mixed monolayer containing synthetic glycolipids at the air—water interface were observed from frequency changes of a quartz-crystal microbalance (QCM) that was attached horizontally on the monolayer from the air phase. Binding constants (k1), dissociation rate constants (k-1, and binding amount (Δm) could be obtained from time courses of the frequency decrease (mass increase) of the QCM. Con A showed the specific binding to 2C18-mal lipids having a glucopyranosyl head group but not 2C18-lac lipids having a galactopyranosyl head group in the matrix of phosphoethanolamine lipids (2C18PE). The maximum binding amount (Δmmax) was independent of the mole fraction of the 2C18-mal, but on the contrary, binding (k1), dissociation rate (k-1), and association constants ( ka= k1/k-1) were affected largely by the content of the 2C18-mal in the monolayer. © 1994, American Chemical Society. All rights reserved.

Interactions of calcium ions with a monolayer of synthetic phospholipid 1,3-dihexadecylglycero-2-phosphoethanolamine (2C16PE) were investigated with three different methods: surface-pressure (π‒A) isotherms, electrochemical reactions on an electrode, and quartz-crystal microbalance (QCM) measurements, π‒A isotherms showed that the 2C16PE monolayer exists with the most condensed molecular packing at pH 5.8 probably due to intermolecular zwitterionic interactions. Ca2+ ions destroy this interaction and expand the monolayer packing. This behavior can be examined on a bilayer-covered SnO2 electrode in electrochemical methods. Oxidation peak currents of a maker ion (Fe(CN)63/4−) in the aqueous phase through the lipid films were increased by the addition of Ca2+ ions only when the membrane was in a bilayer and in the fluid liquid crystalline state above the Tc. The binding behavior of Ca2+ ions onto the 2C16PE LB films was followed directly from the frequency changes of the LB film-deposited QCM. Ca2+ ions can penetrate into the fluid liquid crystalline LB films, but not into the solid films. From these findings, Ca2+ ions can bind and penetrate into only the fluid liquid crystalline state of a bilayer and disturb or expand the membrane structures. © 1994, American Chemical Society. All rights reserved.

The quartz-crystal microbalance (QCM) has been modified to allow for the monitoring of reactions in aqueous solution with about 10 ng sensitivity. This has been achieved by allowing only one electrode to be exposed to the solution of interest, the other being maintained in an air environement. When the gold electrodes of the QCM are thiol/diimide activated, they can be used to monitor the surface immobilization of immunoglobulin (IgG) molecules and their subsequent interaction with anti-IgG. This is demonstrated by immobilization of sheep or mouse IgG onto the thiolated electrodes, with preference shown for binding with anti-sheep and anti-mouse IgGs, respectively, during subsequent solution interaction. Some cross-reactivity occurs. © 1994.

Interaction of various proteins adsorbed from solution with a phospholipid monolayer at the air-water interface of a Langmuir film balance has been studied quantitatively by using a quartz-crystal microbalance (QCM) which was attached horizontally on the monolayer from the air phase. Adsorption amounts and penetration behaviors of proteins have been followed by observing frequency changes of the QCM at the air-water interface and surface pressure changes of the monolayer. © 1993, American Chemical Society. All rights reserved.

Catalytic hydrolysis of phospholipid Langmuir-Blodgett (LB) films deposited on a quartz-crystal microbalance (QCM) by phospholipase A2 was followed by observing frequency changes of the QCM in an aqueous solution.

A monolayer of a triethoxysilane amphiphile having two 18-carbon alkyl chains (2CigSi) was polymerized to form a Si-O-Si linkage on an acidic water subphase, transferred onto a Sn02 electrode by a Langmuir-Blodgett (LB) technique, and then covalently immobilized with Si-O-Sn linkages on the electrode. The polymerized and covalently immobilized 2CigSi monolayer was much more stable on the electrode in harsh aqueous conditions than were noncovalently bonded monolayers. The 2CisSi monolayer impeded the oxidation of Fe(CN)64 as seen in the ratio of peak currents at the monolayer-covered and uncovered electrodes (ip/ip= 0.2). The reactivity could be controlled reversibly by the phase transition from solid to liquid crystalline state of the monolayer. The value ip/ip= 0.2 indicates that the 2CigSi monolayer on the Sn02 electrode cannot completely block the penetration of ferrocyanide ions and still contains pinhole defects in the monolayer, probably because the Sn02 electrode has the rough surface of metal oxides. These defects can be completely eliminated by adsorbing a small amount of a long-chain alcohol (C14OH to Ci80H) into the monolayer but not by adsorbing branched bulky alcohols or short-chain alcohols (C60H to C10OH). © 1990, American Chemical Society. All rights reserved.

Epigallocatechin-3-O-gallate (EGCG) is the major catechin component of green tea (Cameria sinensis), and is known to possess antiviral activities against a wide range of DNA viruses and RNA viruses. However, few studies have examined chemical modifications of EGCG in terms of enhanced antiviral efficacy. This paper discusses which steps of virus infection EGCG interferes with, citing previous reports. EGCG appears most likely to inhibits the early stage of infections, such as attachment, entry, and membrane fusion, by interfering with viral membrane proteins. According to the relationships between structure and antiviral activity of catechin derivatives, the 3-galloyl and 5'-OH group of catechin derivatives appear critical to antiviral activities. Enhancing the binding affinity of EGCG to virus particles would thus be important to increase virucidal activity. We propose a newly developed EGCG-fatty acid derivative in which the fatty acid on the phenolic hydroxyl group would be expected to increase viral and cellular membrane permeability. EGCG-fatty acid monoesters showed improved antiviral activities against different types of viruses, probably due to their increased affinity for virus and cellular membranes. Our study promotes the application of EGCG-fatty acid derivatives for the prevention and treatment of viral infections.

Quartz Crystal Microbalances (QCM) are known to provide very sensitive mass measuring devices because the resonance frequency decreases upon the increase of a given mass on the QCM electrode in a nanogram level. In this review, we describe that the QCM is useful to detect molecular recognition processin situ. For example, when lipid membranes are immobilized on a QCM plate, we could detect the selective adsorption of odor molecules to the lipid matrix from the freqency changes. When dipeptide crystals were immobilized, enantioselective adsorption of amino acid was observed. When the QCM plate was attached hollizontally onto the glycolipid monolayer at the air-water interface, the selective binding of lecithins onto the glycolipid monolayer was observed. When oligonucleotide was immobilized on a QCM, hybridization of DNA double strands were detected from frequency changes.

種々のアルキルシラン化合物の単分子膜を多孔質ガラス板上に吸着法で固定化し,それを通してのNaClや水溶牲蛍光プローブの透過性について検討した。ジアルキルシラン化合物から成る単分子膜の場合には・透過性が未修飾多孔質ガラス板の場合の1/10～1/100に抑制され,単分子膜の結晶一液晶相転移温度Tc付近で透過性の大きな変化が観測された。モノアルキルシラン化合物単分子膜の場合には・透過性はそれほど抑制されず,相転移の効果も認められなかった。そのほか,単分子膜表面の親疎水性,多孔質ガラス板の孔径,スペーサーの長さの効果,およびLB型単分子膜との比較について検討した.