Adsorption of Different Ionic Types of Polyacrylamide on Montmorillonite Surface: Insight from QCM-D and Molecular Dynamic Simulation.

This study investigates the interaction between montmorillonite and polyacrylamide (PAM) with different ionic types using quartz crystal microbalance with dissipation monitoring (QCM-D) and molecular dynamics (MD) simulations. The goal was to understand the effect of ionicity and ionic type on polymer deposition on montmorillonite surfaces. The results of the QCM-D analysis showed that a decrease in pH led to an increase in the adsorption of montmorillonite on the alumina surface. The ranking of adsorption mass on alumina and pre-adsorbed montmorillonite alumina surfaces was found to be cationic polyacrylamide (CPAM) > polyacrylamide (NPAM) > anionic polyacrylamide (APAM). The study also found that CPAM had the strongest bridging effect on montmorillonite nanoparticles, followed by NPAM, while APAM had a negligible bridging effect. The MD simulations showed that ionicity had a significant influence on the adsorption of polyacrylamides. The cationic functional group N(CH3)3+ had the strongest attraction interaction with the montmorillonite surface, followed by the hydrogen bonding interaction of the amide functional group CONH2, and the anionic functional group COO- had a repulsive interaction. The results suggest that at high ionicity levels, CPAM can be adsorbed on the montmorillonite surface, while at low ionicity levels, APAM may still be adsorbed with a strong coordination trend.

Complementary Operando Electrochemical Quartz Crystal Microbalance and UV/Vis Spectroscopic Studies: Acetate Effects on Zinc-Manganese Batteries.

Zinc-ion batteries, in which zinc ions and protons do intercalation and de-intercalation during battery cycling with various proposed mechanisms under debate, have been studied. Recently, electrolytic zinc-manganese batteries, exhibiting the pure dissolution-deposition behavior with a large charge capacity, have been accomplished through using electrolytes with Lewis acid. However, the complicated chemical environment and mixed products hinder the investigation though it is crucial to understand the detailed mechanism. Here, cyclic voltammetry coupled electrochemical quartz crystal microbalance (EQCM) and ultraviolet-visible spectrophotometry (UV-Vis) are respectively, for the very first time, used to study the transition from zinc-ion batteries to zinc electrolytic batteries by the continuous addition of acetate ions. These complementary techniques operando trace the mass and the composition evolution. The observed formation and dissolution of zinc hydroxide sulfate (ZHS) and manganese oxides evince the effect of acetate ions on zinc-manganese batteries from an alternative perspective. Both the amount of acetate and the pH value have large impacts on the capacity and Coulombic efficiency of the MnO2 electrode, and thus they should be optimized when constructing a full zinc-manganese battery with high rate capability and reversibility.

Quartz Crystal Microbalance Technology Coupled with Impedance for the Dynamic Monitoring of the Cardiomyocyte Beating Function and Drug Screening.

The main sensing techniques used to study myocardial pulsation are electrical impedance sensing (EIS) and by quartz crystal microbalance (QCM). While electrical impedance technology is the gold standard for the study of myocardial pulsation, the clinical application of drugs is being followed up in real time additionally, thus, QCM technology needs to be further developed as a very important class of quality sensor technology. Moreover, the application of EIS, in combination with the QCM, for monitoring myocardial pulsation, has been rarely reported. In this paper, a series of cell growth and adhesion conditions were optimized using rat primary cardiomyocytes, and QCM was used in combination with EIS to monitor the adhesion and the myocardial pulsation ability of the cells in real time. Furthermore, cardiomyocytes that adhered to the QCM and EIS were treated with isoprenaline (ISO), a positive inotropic drug, and verapamil (VRP), a negative inotropic drug. Next, the cell index (CI)-time (T) plots, beating amplitude (BA) and beating rate (BR) of the cardiomyocytes were calculated and changes in these parameters, before and after, dosing were evaluated. The results showed that the QCM technique results were not only consistent with the results obtained with EIS, but also that the QCM technique had a certain degree of sensitivity for the calculation of cardiomyocyte beating. Thus, our findings validate the reliability and validity of the QCM technique for measuring cardiomyocyte beating and drug testing. We hope that further studies would evaluate the application of the QCM technology for clinical use.

Smart bio-nano interface derived from zein protein as receptors for biotinyl moiety.

Proteinaceous, tunable nanostructures of zein (prolamine of corn) were developed as biotinyl-specific receptors using a molecular imprinting technique. Sacrificial templates, such as latex beads (LB3) and anodized alumina membrane (AAM), have been used to control nanostructural patterns in biotin-imprinted zein (BMZ). Briefly, a methanolic solution of the zein-biotin complex was drop cast upon a self-organized LB3 and AAM templates on Au/quartz surfaces. Subsequent dissolution of these sacrificial templates affords highly oriented, predetermined, and uniformly grown hyperporous (300 nm) and nanowires (150 nm) motifs of zein (BMZ-LB3 and BMZ-AAM), as shown by scanning electron microscopy (SEM). Selective extraction of biotin molecular template cast-off site-selective biotin imprints within these zein nanostructures complementary to biotinyl moieties. Alternatively, biotin-imprinted zein nanoparticles (BMZ-Np) and thin film (BMZ-MeOH) were prepared by coacervation and drop casting methods, respectively. Density functional theoretical (DFT) studies reveal strong hydrogen-bonded interaction of biotin with serine and glutamine residues of zein. Quartz crystal microbalance (QCM) studies show remarkable sensitivity of the hyperporous-BMZ-LB3 and nanowires of BMZ-AAM towards biotin derivative (biotin methyl ester) by five (24.75 ± 1.34 Hz/mM) and four (18.19 ± 0.75 Hz/mM) times, respectively, higher than the BMZ-MeOH. Enhanced permeability features of the zein nanostructures, when templated with LB3, enable the QCM detection of biotin- or its derivatives down to 12.9 ng mL-1 from dairy products (Kefir). The outcome of this study shall be a key aspect in interfacing biological materials with micro-/nano-sensors and electronic devices for detecting pertinent analytes using sustainably developed biopolymer-based nanostructures.

Preparation of Ultrathin and Degradable Polymeric Films by Electropolymerization of 3-Amino-l-tyrosine.

Bioderived polymers are one of many current research areas that promise a sustainable future. Due to their unique properties, the bioderived polymer polydopamine has been in the spotlight over the last decades. Its ability to adhere to virtually any surface and its stability over a wide pH range as well as in several organic solvents make it a suitable candidate for various applications like coatings and biosensors. However, strong light absorption over a broad range of wavelengths and high quenching efficiency limit its uses. Therefore, new bioderived polymers with similar features to polydopamine but without fluorescence quenching properties are highly desirable. Herein, the electropolymerization of a bioderived analog of dopamine, 3-amino-l-tyrosine, is demonstrated. The resulting polymer, poly(amino-l-tyrosine), exhibits several characteristics complementary to or even exceeding those of polydopamine and its analog, polynorepinephrine, rendering poly(amino-l-tyrosine) attractive for the development of sensors and photoactive devices. Cyclic voltammetry, spectro-electrochemistry, and electrochemical quartz crystal microbalance measurements are applied to study the electrodeposition of this material, and the resulting films are compared to polydopamine and polynorepinephrine. Impedance spectroscopy reveals increased ion permeability of poly(amino-l-tyrosine) compared to polydopamine and polynorepinephrine. Moreover, the reduced fluorescence quenching of poly(amino-l-tyrosine) supports its use as coating for biosensors and organic semiconductors.

A study of vegetable oil modified QCM sensor to detect ß-pinene in Indian cardamom.

A quartz crystal microbalance (QCM) sensor was developed in this study with the vegetable oil from olive (OLV-QCM) to detect an important volatile organic compound, ß-pinene in Indian cardamom. Hydrophobic vegetable oil from olive, which contains oleic acid and omega-9, a monounsaturated fatty acid was found to be suitable for binding ß-pinene through non-covalent bonds. The fabricated QCM sensor coating was examined with the field emission scanning electron microscope (FESEM) and Fourier-transform infrared spectroscopy (FTIR) to determine its surface morphology and chemical compositions. The sensitivity, reproducibility, repeatability, and reusability were studied for the developed sensor. Notably, the sensor was observed to be highly selective towards ß-pinene as compared to the other volatile components present in cardamom. The limit of detection (LOD) and limit of quantitation (LOQ) parameters were determined as 5.57 mg L-1 and 18.57 mg L-1, respectively. Moreover, the adsorption isotherm models of the sensor were studied to validate the physical adsorption affinity towards ß-pinene applying Langmuir, Freundlich, and Langmuir-Freundlich isotherm models. The sensor showed a correlation factor of 0.99 with the peak area percentage of gas chromatography-mass spectrometry (GC-MS) analysis for ß-pinene in cardamom samples. The sensor was prepared with natural vegetable oil, unlike health hazard chemicals. In addition to this, the low-cost, easy fabrication process ensured the suitability of the sensor for practical deployment.

Crystalline phase and surface coating of Al2O3 nanoparticles and their influence on the integrity and fluidity of model cell membranes.

Aluminium oxide nanoparticles (Al2O3 NPs) potentially cause health hazards after their release into the environment. The crystalline phase of Al2O3 NPs determines their surface structure and the number of functional groups. The adsorption of natural organic matter (NOM) or biomolecules on the surface Al2O3 NPs also alters their surface properties and subsequent interactions with organisms. In this study, the roles of the Al2O3 crystalline phase and the surface coating of the nanoparticles on the membrane integrity and fluidity were investigated. Giant and small unilamellar vesicles (GUVs and SUVs) were prepared as model cell membranes to detect membrane disruption after exposure to Al2O3 NPs. Due to amorphous structure and high surface activity of γ-Al2O3 NPs, they had a stronger affinity with the membrane and caused more serious membrane rupture than that of α-Al2O3 NPs. The deposition of Al2O3 NPs on the membrane and the induced membrane disruption were monitored by a quartz crystal microbalance with dissipation (QCM-D) method. HA-coated Al2O3 NPs disrupted the SUV layer on the QCM-D sensor, while BSA-coated Al2O3 NPs only adhered to the membrane and induced unremarkable vesicle disruption. In addition, untreated γ-Al2O3 NPs induced remarkable gelation of a negatively charged membrane, but other types of Al2O3 NPs caused negligible membrane phase changes. The outcomes of this study demonstrate that the crystalline phase of the Al2O3 NPs affects the integrity and fluidity of cell membranes. The protein coatings on the NPs weaken the NP-membrane interaction, while HA coatings increase the damage of the NP-induced interaction.

The Impact of the Metal Interface on the Stability and Quality of a Therapeutic Fusion Protein.

Subvisible particle formation, which occurs after the sterile filtration step of the fill/finish process, is a challenge that may occur during the development of biotherapeutics with complex molecular structures. Here, we show that a stainless steel pump head from a rotary piston pump produces more protein aggregates, past the limit of the acceptable quality range for subvisible particle counts, in comparison to a ceramic pump head. The quartz crystal microbalance was used to quantify the primary layer, proteins irreversibly adsorbed at the solid-liquid interface, and the secondary diffuse gel-like layer interacting on top of the primary layer. The results showed that the mass of protein irreversibly adsorbed onto stainless steel sensors is greater than on an aluminum oxide surface (ceramic pump mimic). This suggests that the amount of adsorbed protein plays a role in surface-induced protein aggregation at the solid-liquid interface.

Control of Probe Density at DNA Biosensor Surfaces Using Poly(l-lysine) with Appended Reactive Groups.

Biosensors and materials for biomedical applications generally require chemical functionalization to bestow their surfaces with desired properties, such as specific molecular recognition and antifouling properties. The use of modified poly(l-lysine) (PLL) polymers with appended oligo(ethylene glycol) (OEG) and thiol-reactive maleimide (Mal) moieties (PLL-OEG-Mal) offers control over the presentation of functional groups. These reactive groups can readily be conjugated to, for example, probes for DNA detection. Here we demonstrate the reliable conjugation of thiol-functionalized peptide nucleic acid (PNA) probes onto predeposited layers of PLL-OEG-Mal and the control over their surface density in the preceding synthetic step of the PLL modification with Mal groups. By monitoring the quartz crystal microbalance (QCM) frequency shifts of the binding of complementary DNA versus the density of Mal moieties grafted to the PLL, a linear relationship between probe density and PLL grafting density was found. Cyclic voltammetry experiments using Methylene Blue-functionalized DNA were performed to establish the absolute probe density values at the biosensor surfaces. These data provided a density of 1.2 × 1012 probes per cm2 per % of grafted Mal, thus confirming the validity of the density control in the synthetic PLL modification step without the need of further surface characterization.

Versatile nano-platform for tailored immuno-magnetic carriers.

Custom immuno-magnetic devices are desirable tools for biomedical and biotechnological applications. Herein, surface active maghemite nanoparticles (SAMNs) are proposed as a versatile platform for developing tailored immuno-magnetic nano-carriers by simple wet reactions. Two examples for conjugating native and biotinylated antibodies were presented along with their successful applications in the recognition of specific foodborne pathogens. Nanoparticles were functionalized with rhodamine B isothiocyanate (RITC), leading to a fluorescent nano-conjugate, and used for binding anti-Campylobacter fetus antibodies (SAMN@RITC@Anti-Cf). The microorganism was selectively captured in the presence of two other Campylobacter species (C. jejuni and C. coli), as verified by PCR. Alternatively, SAMNs were modified with avidin, forming a biotin-specific magnetic nano-carrier and used for the immobilization of biotinylated anti-Listeria monocytogenes antibodies (SAMN@avidin@Anti-Lm). This immuno-magnetic carrier was integrated in piezoelectric quartz crystal microbalance (QCM) sensor for the detection of L. monocytogenes in milk, showing a detection limit of 3 bacterial cells. The present work presents a new category of customized immuno-magnetic nano-carriers as a competitive option for suiting specific applications. Graphical abstract ᅟ.

Water Retention of Calcium-Containing Pectin Studied by Quartz Crystal Microbalance and Infrared Spectroscopy with a Humidity Control System.

To examine differences of water-retention mechanisms between pectins with and without Ca2+, quartz crystal microbalance (QCM) and infrared microspectroscopy combined with a humidity-control system were used to analyze differences in amounts and species of adsorbed water to pectins without and with Ca2+. QCM analysis shows that water contents are ∼2-3 times larger for the pectin film with Ca2+ than that without Ca2+. The difference IR spectra suggest that long, medium, and short H-bond water molecules (free, medium, and bound water) are adsorbed to the pectin film without Ca2+. IR peak shifts of C═O of COOH and C-OH suggest that these water molecules are hydrogen-bonded to C═O and C-OH groups. In addition to these water molecules, bulk water is adsorbed. IR OH band areas fitted by four Gaussian components show that bulk water is mainly adsorbed to the pectin film with Ca2+, possibly among skeletal chains of pectin bridged by Ca2+.

Solar Water Splitting with a Hydrogenase Integrated in Photoelectrochemical Tandem Cells.

Hydrogenases (H2 ases) are benchmark electrocatalysts for H2 production, both in biology and (photo)catalysis in vitro. We report the tailoring of a p-type Si photocathode for optimal loading and wiring of H2 ase through the introduction of a hierarchical inverse opal (IO) TiO2 interlayer. This proton-reducing Si|IO-TiO2 |H2 ase photocathode is capable of driving overall water splitting in combination with a photoanode. We demonstrate unassisted (bias-free) water splitting by wiring Si|IO-TiO2 |H2 ase to a modified BiVO4 photoanode in a photoelectrochemical (PEC) cell during several hours of irradiation. Connecting the Si|IO-TiO2 |H2 ase to a photosystem II (PSII) photoanode provides proof of concept for an engineered Z-scheme that replaces the non-complementary, natural light absorber photosystem I with a complementary abiotic silicon photocathode.

Real-time evaluation of natural organic matter deposition processes onto model environmental surfaces.

Natural organic matter (NOM) is ubiquitous in aqueous systems and dynamically partitions onto/from environmental surfaces. However, such interfacial processes have not been uniformly quantified in situ and in real time. In this work, adsorption and deposition processes of Suwannee River humic acid (SRHA) and Suwannee River fulvic acid (SRFA), as model NOM, were evaluated for a series of environmentally relevant interfaces. Real-time, interfacial phenomenon, including deposition, release, and adlayer viscoelastic properties, were quantified over a variety of water chemistries via quartz crystal microbalance with dissipation monitoring (QCM-D). Specifically, adlayer mass and deposition rates of SRHA and SRFA were evaluated as a function of NOM concentration/molecular weight (fraction), pH, electrolyte composition (type and concentration), and collector surface type. For these, the adsorption of SRHA onto aluminum oxide (Al2O3) and polystyrene (PS) surfaces follows the Langmuir isotherm model. Rapid, near-monolayer formation of SRHA/SRFA adlayers were observed on Al2O3, hydroxyapatite (HAP), and poly (l-lysine) (PLL) surfaces, but not on PS or iron oxide (Fe3O4) surfaces. The presence of divalent cations (Ca2+/Mg2+) at relatively low concentrations (0.5-5.0 mM) significantly enhances the mass of SRHA/SRFA deposited onto the surfaces of silica (SiO2), Al2O3, and PS. Viscoelastic properties of the adsorbed layer based on the ratio of dissipation to frequency revealed a relatively unique adlayer structure for SRHA in the presence of 5.0 mM Ca2+.

A high-throughput QCM chip configuration for the study of living cells and cell-drug interactions.

In this study, we present a novel design of interference-free, negligible installation-induced stress, suitable for the fabrication of high-throughput quartz crystal microbalance (HQCM) chips. This novel HQCM chip configuration was fabricated using eight independent yet same-batch quartz crystal resonators within a common glass substrate with eight through-holes of diameter slightly larger than that of the quartz resonator. Each quartz resonator's rim was adhered to the inner part of the through-hole via silicone glue to form the rigid (quartz)-soft (silicone)-rigid (glass) structure (RSRS) which effectively eliminates the acoustic couplings among different resonators and largely alleviates the installation-induced stresses. The consistence of the eight resonators was verified by very similar equivalent circuit parameters and very close response slopes to liquid density and viscosity. The HQCM chip was then employed for real-time and continuous monitoring of H9C2 cardiomyoblast adhesions and viscoelastic changes induced by the treatments of two types of drugs: drugs that affect the cytoskeletons, including nocodazole, paclitaxel, and Y-27632, and drugs that affect the contractile properties of the cells: verapamil and different dosages of isoprenaline. Meanwhile, we compared the cytoskeleton affecting drug-induced viscoelastic changes of H9C2 with those of human umbilical vein endothelial cells (HUVECs). The results described here provide the first solution to fabricate HQCM chips that are free from the limitation of resonator number, installation-induced stress, and acoustic interferences among resonators, which should find wide applications in areas of cell phenotype assay, cytotoxicity test, drug evaluation and screening, etc. Graphical abstract Schematic illustration of the principle and configuration of interference-free high-throughput QCM chip to evaluate and screen drugs based on cell viscoelasticity.

PE859, A Novel Curcumin Derivative, Inhibits Amyloid-ß and Tau Aggregation, and Ameliorates Cognitive Dysfunction in Senescence-Accelerated Mouse Prone 8.

Aggregation of amyloid-ß (Aß) and tau plays a crucial role in the onset and progression of Alzheimer's disease (AD). Therefore, the inhibition of Aß and tau aggregation may represent a potential therapeutic target for AD. Herein, we designed and synthesized both Aß and tau dual aggregation inhibitors based on the structure of curcumin and developed the novel curcumin derivative PE859. In this study, we investigated the inhibitory activity of PE859 on Aß aggregationin vitro and the therapeutic effects of PE859 on cognitive dysfunction via dual inhibition of Aß and tau aggregation in vivo. PE859 inhibited Aß aggregation in vitro and protected cultured cells from Aß-induced cytotoxicity. Furthermore, PE859 ameliorated cognitive dysfunction and reduced the amount of aggregated Aß and tau in brains of senescence-accelerated mouse prone 8 (SAMP8). These results warrant consideration of PE859 as a candidate drug for AD.

Real-Time Quartz Crystal Microbalance Monitoring of Free Docosahexaenoic Acid Interactions with Supported Lipid Bilayers.

Docosahexaenoic acid (DHA) is the most abundant polyunsaturated omega-3 fatty acid found in mammalian neuronal cell membranes. Although DHA is known to be important for neuronal cell survival, little is know about how DHA interacts with phospholipid bilayers. This study presents a detailed quartz crystal microbalance with dissipation monitoring (QCM-D) analysis of free DHA interactions with individual and mixed phospholipid supported lipid bilayers (SLB). DHA incorporation and subsequent changes to the SLBs viscoelastic properties were observed to be concentration-dependent, influenced by the phospholipid species, the headgroup charge, and the presence or absence of calcium ions. It was observed that 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) SLBs incorporated the greatest amount of DHA concentration, whereas the presence of phospholipids, phosphatidylserine (PS), and phosphatidylinositol (PI) in a POPC SLB significantly reduced DHA incorporation and changed the SLBs physicochemical properties. These observations are hypothesized to be due to a substitution event occurring between DHA and phospholipid species. PS domain formation in POPC/PS 8:2 SLBs was observed in the presence of calcium ions, which favored DHA incorporation to a similar level as for a POPC only SLB. The changes in SLB thickness observed with different DHA concentrations are also presented. This work contributes to an understanding of the physical changes induced in a lipid bilayer as a consequence of its exposure to different DHA concentrations (from 50 to 200 µM). The capacity of DHA to influence the physical properties of SLBs indicates the potential for dietary DHA supplementation to cause changes in cellular membranes in vivo, with subsequent physiological consequences for cell function.

Influence of the sulfation degree of glycosaminoglycans on their multilayer assembly with poly-l-lysine.

We report on the build-up and the intrinsic properties of polyelectrolyte multilayer films from poly-l-lysine and glycosaminoglycans (GAGs) with different sulfation degree, i.e. different charge. We used three complementary techniques, namely electrokinetic analysis (EKA), quartz-crystal microbalance with dissipation (QCM-D) and surface plasmon resonance (SPR), to characterize the assembly process and to assess the properties of the obtained films. EKA elucidated the contribution of the polymers charged groups to the net surface charge of the films and suggested that the assembly process is not solely driven by electrostatic interactions. The combined analysis of QCM-D and SPR data demonstrated that the mechanical properties of the films are dependent on the polymer charge: sulfated GAGs (heparin and chondroitin sulfate) form elastic films while hyaluronan (no sulfation) assembles into multilayer constructs with viscous behavior. The contribution of the water content to these distinct regimes is also discussed. Finally, we show that rather complete characterization of the film properties is possible by SPR employing the two-wavelength and two-media approach: thickness, adsorbed mass, refractive index, and interaction kinetics of the assembly process can be studied by SPR alone.

Correlating single-molecule and ensemble-average measurements of peptide adsorption onto different inorganic materials.

The coating of solid-binding peptides (SBPs) on inorganic material surfaces holds significant potential for improved surface functionalization at nano-bio interfaces. In most related studies, the goal has been to engineer peptides with selective and high binding affinity for a target material. The role of the material substrate itself in modulating the adsorption behavior of a peptide molecule remains less explored and there are few studies that compare the interaction of one peptide with different inorganic substrates. Herein, using a combination of two experimental techniques, we investigated the adsorption of a 16 amino acid-long random coil peptide to various inorganic substrates - gold, silicon oxide, titanium oxide and aluminum oxide. Quartz crystal microbalance-dissipation (QCM-D) experiments were performed in order to measure the peptide binding affinity for inorganic solid supports at the ensemble average level, and atomic force microscopy (AFM) experiments were conducted in order to determine the adhesion force of a single peptide molecule. A positive trend was observed between the total mass uptake of attached peptide and the single-molecule adhesion force on each substrate. Peptide affinity for gold was appreciably greater than for the oxide substrates. Collectively, the results obtained in this study offer insight into the ways in which inorganic materials can differentially influence and modulate the adhesion of SBPs.

Graphene Oxide and Lipid Membranes: Size-Dependent Interactions.

We have investigated the interaction of graphene oxide (GO) sheets with supported lipid membranes with focus on how the interaction depends on GO sheet size (three samples in the range of 90-5000 nm) and how it differs between small and large liposomes. The layer-by-layer assembly of these materials into multilamellar structures, as discovered in our previous research, is now further explored. The interaction processes were monitored by two complementary, real time, surface-sensitive analytical techniques: quartz crystal microbalance with dissipation monitoring (QCM-D, electroacoustic sensing) and indirect nanoplasmonic sensing (INPS, optical sensing). The results show that the sizes of each of the two components, graphene oxide and liposomes, are important parameters affecting the resulting multilayer structures. Spontaneous liposome rupture onto graphene oxide is obtained for large lateral dimensions of the graphene oxide sheets.

Self-assembly formation of lipid bilayer coatings on bare aluminum oxide: overcoming the force of interfacial water.

Widely used in catalysis and biosensing applications, aluminum oxide has become popular for surface functionalization with biological macromolecules, including lipid bilayer coatings. However, it is difficult to form supported lipid bilayers on aluminum oxide, and current methods require covalent surface modification, which masks the interfacial properties of aluminum oxide, and/or complex fabrication techniques with specific conditions. Herein, we addressed this issue by identifying simple and robust strategies to form fluidic lipid bilayers on aluminum oxide. The fabrication of a single lipid bilayer coating was achieved by two methods, vesicle fusion under acidic conditions and solvent-assisted lipid bilayer (SALB) formation under near-physiological pH conditions. Importantly, quartz crystal microbalance with dissipation (QCM-D) monitoring measurements determined that the hydration layer of a supported lipid bilayer on aluminum oxide is appreciably thicker than that of a bilayer on silicon oxide. Fluorescence recovery after photobleaching (FRAP) analysis indicated that the diffusion coefficient of lateral lipid mobility was up to 3-fold greater on silicon oxide than on aluminum oxide. In spite of this hydrodynamic coupling, the diffusion coefficient on aluminum oxide, but not silicon oxide, was sensitive to the ionic strength condition. Extended-DLVO model calculations estimated the thermodynamics of lipid-substrate interactions on aluminum oxide and silicon oxide, and predict that the range of the repulsive hydration force is greater on aluminum oxide, which in turn leads to an increased equilibrium separation distance. Hence, while a strong hydration force likely contributes to the difficulty of bilayer fabrication on aluminum oxide, it also confers advantages by stabilizing lipid bilayers with thicker hydration layers due to confined interfacial water. Such knowledge provides the basis for improved surface functionalization strategies on aluminum oxide, underscoring the practical importance of surface hydration.