Hydration strongly affects the molecular and electronic structure of membrane phospholipids

Effect of Ester Moiety on Structural Properties of Binary Mixed Monolayers of Alpha-Tocopherol Derivatives with DPPC

Phospholipid membranes are ubiquitous components of cells involved in physiological processes; thus, knowledge regarding their interactions with other molecules, including tocopherol ester derivatives, is of great importance. The surface pressure–area isotherms of pure α-tocopherol (Toc) and its derivatives (oxalate (OT), malonate (MT), succinate (ST), and carbo analog (CT)) were studied in Langmuir monolayers in order to evaluate phase formation, compressibility, packing, and ordering. The isotherms and compressibility results indicate that, under pressure, the ester derivatives and CT are able to form two-dimensional liquid-condensed (LC) ordered structures with collapse pressures ranging from 27 mN/m for CT to 44 mN/m for OT. Next, the effect of length of ester moiety on the surface behavior of DPPC/Toc derivatives’ binary monolayers at air–water interface was investigated. The average molecular area, elastic modulus, compressibility, and miscibility were calculated as a function of molar fraction of derivatives. Increasing the presence of Toc derivatives in DPPC monolayer induces expansion of isotherms, increased monolayer elasticity, interrupted packing, and lowered ordering in monolayer, leading to its fluidization. Decreasing collapse pressure with increasing molar ratio of derivatives indicates on the miscibility of Toc esters in DPPC monolayer. The interactions between components were analyzed using additivity rule and thermodynamic calculations of excess and total Gibbs energy of mixing. Calculated excess area and Gibbs energy indicated repulsion between components, confirming their partial mixing. In summary, the mechanism of the observed phenomena is mainly connected with interactions of ionized carboxyl groups of ester moieties with DPPC headgroup moieties where formed conformations perturb alignment of acyl chains, resulting in increasing mean area per molecule, leading to disordering and fluidization of mixed monolayer.

C-Glucosylation as a tool for the prevention of PAINS-induced membrane dipole potential alterations

The concept of Pan-Assay Interference Compounds (PAINS) is regarded as a threat to the recognition of the broad bioactivity of natural products. Based on the established relationship between altered membrane dipole potential and transmembrane protein conformation and function, we investigate here polyphenols' ability to induce changes in cell membrane dipole potential. Ultimately, we are interested in finding a tool to prevent polyphenol PAINS-type behavior and produce compounds less prone to untargeted and promiscuous interactions with the cell membrane. Di-8-ANEPPS fluorescence ratiometric measurements suggest that planar lipophilic polyphenols-phloretin, genistein and resveratrol-act by decreasing membrane dipole potential, especially in cholesterol-rich domains such as lipid rafts, which play a role in important cellular processes. These results provide a mechanism for their labelling as PAINS through their ability to disrupt cell membrane homeostasis. Aiming to explore the role of C-glucosylation in PAINS membrane-interfering behavior, we disclose herein the first synthesis of 4-glucosylresveratrol, starting from 5-hydroxymethylbenzene-1,3-diol, via C-glucosylation, oxidation and Horner-Wadsworth-Emmons olefination, and resynthesize phloretin and genistein C-glucosides. We show that C-glucosylation generates compounds which are no longer able to modify membrane dipole potential. Therefore, it can be devised as a strategy to generate bioactive natural product derivatives that no longer act as membrane dipole potential modifiers. Our results offer a new technology towards rescuing bioactive polyphenols from their PAINS danger label through C-C ligation of sugars.

NMR and MD Simulations Reveal the Impact of the V23D Mutation on the Function of Yeast Oligosaccharyltransferase Subunit Ost4

Asparagine-linked glycosylation, also known as N-linked glycosylation, is an essential and highly conserved co- and post-translational protein modification in eukaryotes and some prokaryotes. In the central step of this reaction, a carbohydrate moiety is transferred from a lipid-linked donor to the side-chain of a consensus asparagine in a nascent protein as it is synthesized at the ribosome. Complete loss of oligosaccharyltransferase (OST) function is lethal in eukaryotes. This reaction is carried out by a membrane-associated multi-subunit enzyme, OST, localized in the endoplasmic reticulum (ER). The smallest subunit, Ost4, contains a single membrane-spanning helix that is critical for maintaining stability and activity of OST. Mutation of any residue from Met18 to Ile24 of Ost4 destabilizes the enzyme complex, affecting its activity. Here, we report solution NMR structures and molecular dynamics simulations of Ost4 and Ost4V23D in micelles. Our studies revealed that while the point mutation did not impact the structure of the protein, it affected its position and solvent exposure in the membrane mimetic environment. Furthermore, our molecular dynamics simulations of the membrane-bound OST complex containing either WT or V23D mutant demonstrated disruption of most hydrophobic helix-helix interactions between Ost4V23D and transmembrane (TM)12 and TM13 of Stt3. This disengagement of Ost4V23D from the OST complex led to solvent exposure of the D23 residue in the hydrophobic pocket created by these interactions. Our study not only solves the structures of yeast Ost4 subunit and its mutant but also provides a basis for the destabilization of the OST complex and reduced OST activity.

Ionic Strength-Dependent Interactions and Dimensions of Adsorbed Zwitterionic Copolymers

We report direct measurements of ionic strength-dependent interactions between different molecular weights of zwitterionic triblock copolymers adsorbed to hydrophobic colloids and surfaces. The zwitterionic copolymers investigated include phosphorylcholine [poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC)] and sulfopropylbetaine [poly(3-( N-2-methacryloyloxyethyl- N, N-dimethyl)ammonatopropanesulfonate) (PMAPS)] end blocks separated by poly(propylene oxide) center blocks. The range of repulsion between adsorbed PMAPS copolymer layers increases with increasing NaCl from 0.01 to 3 M, and layer thicknesses range from ∼50 to 100% of the PMAPS block contour length. In contrast, repulsion between PMPC layers does not change for 0.01-3 M NaCl, and layers remain near full extension at their contour length. NaCl-dependent interactions and inferred layer dimensions correlate with hydrodynamic layer thickness and polymer second virial coefficients. These results suggest that the interaction range and layer thickness of adsorbed zwitterionic copolymers arise from a balance of intramolecular dipolar attraction and repulsion possibly mediated by water solvation. The balance between these competing effects and resulting ionic strength dependence is determined by specific zwitterionic moieties.

Mathematical principles and methods of biological surface lubrication with phospholipids bilayers

This paper presents a mini-review of investigations performed by the authors in the field of hydrodynamic theory of lubrication of biological systems and synthetic processing of results to indicate the influence of biologically live material properties on biological liquid viscosity variations. The goal of the presented study was to demonstrate a new principle of a general mathematical theory applied to the mechanism of hydrodynamic lubrication of human joint cartilage surfaces with phospholipids bilayer and to indicate analytical solutions of hydrodynamic pressure, temperature and bio-fluid velocity components. Moreover, 3D variations of dynamic synovial fluid viscosity are assessed, particularly its variations across the entire film thickness. A new 3D analytical and numerical model has been elaborated on the basis of tribology methods, based on the assumptions of an ultra-thin boundary layer of non-Newtonian fluid. The analysed elements also included phospholipid concentrations, power hydrogen ion and collagen fiber concentrations in synovial, biological fluids, as well as electrostatic field, cartilage or biological surface wettability. The obtained results of our analysis demonstrate relationships which occur among hydrodynamic pressure, human joint load carrying capacity and phospholipid bilayer in the cartilage superficial layer. According to the best knowledge of the Authors, the obtained results may find applications in a broad scope of spatiotemporal models in biology and health science.

Asymmetric electrolytes near structured dielectric interfaces

The ion distribution of electrolytes near interfaces with dielectric contrast has important consequences for electrochemical processes and many other applications. To date, most studies of such systems have focused on geometrically simple interfaces, for which dielectric effects are analytically solvable or computationally tractable. However, all real surfaces display nontrivial structure at the nanoscale and have, in particular, a nonuniform local curvature. Using a recently developed, highly efficient computational method, we investigate the effect of surface geometry on ion distribution and interface polarization. We consider an asymmetric 2:1 electrolyte bounded by a sinusoidally deformed solid surface. We demonstrate that even when the surface is neutral, the electrolyte acquires a nonuniform ion density profile near the surface. This profile is asymmetric and leads to an effective charging of the surface. We furthermore show that the induced charge is modulated by the local curvature. The effective charge is opposite in sign to the multivalent ions and is larger in concave regions of the surface.

Meta-mass shift chemical profiling of metabolomes from coral reefs

Untargeted metabolomics of environmental samples routinely detects thousands of small molecules, the vast majority of which cannot be identified. Meta-mass shift chemical (MeMSChem) profiling was developed to identify mass differences between related molecules using molecular networks. This approach illuminates metabolome-wide relationships between molecules and the putative chemical groups that differentiate them (e.g., H₂, CH₂, COCH₂). MeMSChem profiling was used to analyze a publicly available metabolomic dataset of coral, algal, and fungal mat holobionts (i.e., the host and its associated microbes and viruses) sampled from some of Earth's most remote and pristine coral reefs. Each type of holobiont had distinct mass shift profiles, even when the analysis was restricted to molecules found in all samples. This result suggests that holobionts modify the same molecules in different ways and offers insights into the generation of molecular diversity. Three genera of stony corals had distinct patterns of molecular relatedness despite their high degree of taxonomic relatedness. MeMSChem profiles also partially differentiated between individuals, suggesting that every coral reef holobiont is a potential source of novel chemical diversity.

An unstructured loop that is critical for interactions of the stalk domain of Drp1 with saturated phosphatidic acid

Dynamin-related protein 1 (Drp1) is a dynamin superfamily GTPase, which drives membrane constriction during mitochondrial division. To mediate mitochondrial division, Drp1 is recruited to the mitochondrial outer membrane and is assembled into the division machinery. We previously showed that Drp1 interacts with phosphatidic acid (PA) and saturated phospholipids in the mitochondrial membrane, and this interaction restrains Drp1 in initiating the constriction of mitochondria. Here, we show that the role of saturated acyl chains of phospholipids is independent of their contribution to the membrane curvature or lipid packing suggesting their direct interaction with Drp1. We further show that an unstructured loop in the stalk domain of Drp1 is critical for interaction with unsaturated PA. Our data significantly advance our understanding of this unique protein-lipid interaction involved in mitochondrial division.

CO2-Selective Absorbents in Air: Reverse Lipid Bilayer Structure Forming Neutral Carbamic Acid in Water without Hydration

Emission gas and air contain not only CO₂ but also plentiful moisture, making it difficult to achieve selective CO₂ absorption without hydration. To generate absorbed CO₂ (wet CO₂) under heating, the need for external energy to release the absorbed water has been among the most serious problems in the fields of carbon dioxide capture and storage (CCS) and direct air capture (DAC). We found that the introduction of the hydrophobic phenyl group into alkylamines of CO₂ absorbents improved the absorption selectivity between CO₂ and water. Furthermore, ortho-, meta-, and para-xylylenediamines (OXDA, MXDA, PXDA, respectively) absorbed only CO₂ in air without any hydration. Notably, MXDA·CO₂ was formed as an anhydrous carbamic acid even in water, presumably because it was covered with hydrophobic phenyl groups, which induces a reverse lipid bilayer structure. Dry CO₂ was obtained from heating MXDA·CO₂ at 103-120 °C, which was revealed to involve chemically the Grignard reaction to form the resulting carboxylic acids in high yields.

Optical absorption and electronic spectra of chlorophylls a and b

We report optical and electronic properties of the two main chlorophylls in green plants, namely, chlorophylls a and b. We estimate the electric moments of these molecules and study absorption spectra of the chlorophylls.

Lipids influence the proton pump activity of photosynthetic protein embedded in nanodiscs

We report the lipid-composition dependent photocycle kinetics and proton pump activity of bacteriorhodopsin (bR) embedded in nanodiscs composed of different lipids.

Reparameterized United Atom Model for Molecular Dynamics Simulations of Gel and Fluid Phosphatidylcholine Bilayers

A new united atom parametrization of diacyl lipids like dipalmitoylphosphatidylcholine (DPPC) and the dimyristoylphosphatidylcholine (DMPC) has been constructed based on ab initio calculations to obtain fractional charges and the dihedral potential of the hydrocarbon chains, while the Lennard-Jones parameters of the acyl chains were fitted to reproduce the properties of liquid hydrocarbons. The results have been validated against published experimental X-ray and neutron scattering data for fluid and gel phase DPPC. The derived charges of the lipid phosphatidylcholine (PC) headgroup are shown to yield dipole components in the range suggested by experiments. The aim has been to construct a new force field that retains and improves the good agreement for the fluid phase and at the same time produces a gel phase at low temperatures, with properties coherent with experimental findings. The gel phase of diacyl-PC lipids forms a regular triangular lattice in the hydrocarbon region. The global bilayer tilt obtains an azimuthal value of 31° and is aligned between lattice vectors in the bilayer plane. We also show that the model yields a correct heat of melting as well as decent heat capacities in the fluid and gel phase of DPPC.

A biomimetic hybrid nanoplatform for encapsulation and precisely controlled delivery of theranostic agents. [Corrected]

Nanoparticles have demonstrated great potential for enhancing drug delivery. However, the low drug encapsulation efficiency at high drug-to-nanoparticle feeding ratios and minimal drug loading content in nanoparticle at any feeding ratios are major hurdles to their widespread applications. Here we report a robust eukaryotic cell-like hybrid nanoplatform (EukaCell) for encapsulation of theranostic agents (doxorubicin and indocyanine green). The EukaCell consists of a phospholipid membrane, a cytoskeleton-like mesoporous silica matrix and a nucleus-like fullerene core. At high drug-to-nanoparticle feeding ratios (for example, 1:0.5), the encapsulation efficiency and loading content can be improved by 58 and 21 times, respectively, compared with conventional silica nanoparticles. Moreover, release of the encapsulated drug can be precisely controlled via dosing near infrared laser irradiation. Ultimately, the ultra-high (up to ∼87%) loading content renders augmented anticancer capacity both in vitro and in vivo. Our EukaCell is valuable for drug delivery to fight against cancer and potentially other diseases.

Therapeutic applications of reconstituted HDL: When structure meets function

Reconstituted forms of HDL (rHDL) are under development for infusion as a therapeutic approach to attenuate atherosclerotic vascular disease and to reduce cardiovascular risk following acute coronary syndrome and ischemic stroke. Currently available rHDL formulations developed for clinical use contain apolipoprotein A-I (apoA-I) and one of the major lipid components of HDL, either phosphatidylcholine or sphingomyelin. Recent data have established that quantitatively minor molecular constituents of HDL particles can strongly influence their anti-atherogenic functionality. Novel rHDL formulations displaying enhanced biological activities, including cellular cholesterol efflux, may therefore offer promising prospects for the development of HDL-based, anti-atherosclerotic therapies. Indeed, recent structural and functional data identify phosphatidylserine as a bioactive component of HDL; the content of phosphatidylserine in HDL particles displays positive correlations with all metrics of their functionality. This review summarizes current knowledge of structure-function relationships in rHDL formulations, with a focus on phosphatidylserine and other negatively-charged phospholipids. Mechanisms potentially underlying the atheroprotective role of these lipids are discussed and their potential for the development of HDL-based therapies highlighted.

Free energy of the edge of an open lipid bilayer based on the interactions of its constituent molecules

Lipid-bilayers are the fundamental constituents of the walls of most living cells and lipid vesicles, giving them shape and compartment. The formation and growing of pores in a lipid bilayer have attracted considerable attention from an energetic point of view in recent years. Such pores permit targeted delivery of drugs and genes to the cell, and regulate the concentration of various molecules within the cell. The formation of such pores is caused by various reasons such as changes in cell environment, mechanical stress or thermal fluctuations. Understanding the energy and elastic behaviour of a lipid-bilayer edge is crucial for controlling the formation and growth of such pores. In the present work, the interactions in the molecular level are used to obtain the free energy of the edge of an open lipid bilayer. The resulted free-energy density includes terms associated with flexural and torsional energies of the edge, in addition to a line-tension contribution. The line tension, elastic moduli, and spontaneous normal and geodesic curvatures of the edge are obtained as functions of molecular distribution, molecular dimensions, cutoff distance, and the interaction strength. These parameters are further analyzed by implementing a soft-core interaction potential in the microphysical model. The dependence of the elastic free-energy of the edge to the size of the pore is reinvestigated through an illustrative example, and the results are found to be in agreement with the previous observations.

Functional characterization of a fatty acid double-bond hydratase from Lactobacillus plantarum and its interaction with biosynthetic membranes

Hydrogenation of linoleic acid and other polyunsaturated fatty acids is a detoxification mechanism that is present in the Lactobacillus genus of lactic bacteria. The first stage in this multi-step process is hydration of the substrate with formation of 10-hydroxy-9-cis-octadecenoic acid due to fatty-acid hydratase activity that has been detected only in the membrane-associated cell fraction; however, its interaction with the cell membrane is unknown. To provide information in this respect we characterized the homotrimeric 64.7 kDa-native protein from Lactobacillus plantarum; afterwards, it was reconstituted in proteoliposomes and analyzed by confocal fluorescence microscopy. The results showed that hydratase is an extrinsic-membrane protein and hence, the enzymatic reaction occurs at the periphery of the cell. This location may be advantageous in the detoxifying process since the toxic linoleic acid molecule can be bound to hydratase and converted to non-toxic 10-hydroxy-9-cis-octadecenoic acid before it reaches cell membrane. Additionally, we propose that the interaction with membrane periphery occurs through electrostatic contacts. Finally, the structural model of L. plantarum hydratase was constructed based on the amino acid sequence and hence, the putative binding sites with linoleic acid were identified: site 1, located in an external hydrophobic pocket at the C-terminus of the protein and site 2, located at the core and in contact with a FAD molecule. Interestingly, it was found that the linoleic acid molecule arranges around a methionine residue in both sites (Met154 and Met81, respectively) that acts as a rigid pole, thus playing a key role in binding unsaturated fatty acids.

Thermodynamic evaluation of vesicles shed by erythrocytes at elevated temperatures

Erythrocytes undergo structural transformation and shed small vesicles at elevated temperatures. To characterize mechanisms of the phenomenon, the Arrhenius and Eyring equations were used for analysis of the literature, experimental data on vesiculation of human and rat erythrocytes after the temperature was elevated by physical exercise or by exposure to external heat. The thermodynamic analysis of the data showed that erythrocyte transformation, vesicle release, and other associated processes are driven by entropy with enthalpy-entropy compensation. It is suggested that the physical state of the hydrated cell membrane is responsible for the compensation. The increase of vesicle number related to elevated temperatures may be indicative of the heat stress level and serve as diagnostic of erythrocyte stability and human performance.

Electric Field Effect on Phospholipid Monolayers at an Aqueous-Organic Liquid-Liquid Interface

The electric potential difference across cell membranes, known as the membrane potential, plays an important role in the activation of many biological processes. To investigate the effect of the membrane potential on the molecular ordering of lipids within a biomimetic membrane, a self-assembled monolayer of 1-stearoyl-2-oleoyl-sn-glycero-3-phosphocholine (SOPC) lipids at an electrified 1,2-dichloroethane/water interface is studied with X-ray reflectivity and interfacial tension. Measurements over a range of electric potential differences, -150 to +130 mV, that encompass the range of typical biomembrane potentials demonstrate a nearly constant and stable structure whose lipid interfacial density is comparable to that found in other biomimetic membrane systems. Measurements at higher positive potentials, up to 330 mV, illustrate a monotonic decrease in the lipid interfacial density and accompanying variations in the interfacial configuration of the lipid. Molecular dynamics simulations, designed to mimic the experimental conditions, show that the measured changes in lipid configuration are due primarily to the variation in area per lipid with increasing applied electric field. Rotation of the SOPC dipole moment by the torque from the applied electric field appears to be negligible, except at the highest measured potentials. The simulations confirm in atomistic detail the measured potential-dependent characteristics of SOPC monolayers. Our hybrid study sheds light on phospholipid monolayer stability under different membrane potentials, which is important for understanding membrane processes. This study also illustrates the use of X-ray surface scattering to probe the ordering of surfactant monolayers at an electrified aqueous-organic liquid-liquid interface.

Enhancing radiotherapy by lipid nanocapsule-mediated delivery of amphiphilic gold nanoparticles to intracellular membranes

Amphiphilic gold nanoparticles (amph-NPs), composed of gold cores surrounded by an amphiphilic mixed organic ligand shell, are capable of embedding within and traversing lipid membranes. Here we describe a strategy using crosslink-stabilized lipid nanocapsules (NCs) as carriers to transport such membrane-penetrating particles into tumor cells and promote their transfer to intracellular membranes for enhanced radiotherapy of cancer. We synthesized and characterized interbilayer-crosslinked multilamellar lipid vesicles (ICMVs) carrying amph-NPs embedded in the capsule walls, forming Au-NCs. Confocal and electron microscopies revealed that the intracellular distribution of amph-NPs within melanoma and breast tumor cells following uptake of free particles vs Au-NCs was quite distinct and that amph-NPs initially delivered into endosomes by Au-NCs transferred over a period of hours to intracellular membranes through tumor cells, with greater intracellular spread in melanoma cells than breast carcinoma cells. Clonogenic assays revealed that Au-NCs enhanced radiotherapeutic killing of melanoma cells. Thus, multilamellar lipid capsules may serve as an effective carrier to deliver amphiphilic gold nanoparticles to tumors, where the membrane-penetrating properties of these materials can significantly enhance the efficacy of frontline radiotherapy treatments.

Label-free characterization of biomembranes: from structure to dynamics

We review recent progress in the study of the structure and dynamics of phospholipid membranes and associated proteins, using novel label-free analytical tools. We describe these techniques and illustrate them with examples highlighting current capabilities and limitations. Recent advances in applying such techniques to biological and model membranes for biophysical studies and biosensing applications are presented, and future prospects are discussed.

Two cholesterol derivative-based PEGylated liposomes as drug delivery system, study on pharmacokinetics and drug delivery to retina

In this study, two cholesterol derivatives, (4-cholesterocarbonyl-4'-(N,N,N-triethylamine butyloxyl bromide) azobenzene (CAB) and 4-cholesterocarbonyl-4'-(N,N-diethylamine butyloxyl) azobenzene (ACB), one of which is positively charged while the other is neutral, were synthesized and incorporated with phospholipids and cholesterol to form doxorubicin (DOX)-loaded liposomes. PEGylation was achieved by including 1,2-distearoyl-sn-glycero-3-phosphatiylethanol-amine-N-[methoxy-(polyethylene glycol)-2000 (DSPE-PEG2000). Our results showed that PEGylated liposomes displayed significantly improved stability and the drug leakage was decreased compared to the non-PEGylated ones in vitro. The in vivo study with rats also revealed that the pharmacokinetics and circulation half-life of DOX were significantly improved when liposomes were PEGylated (p < 0.05). In particular, the neutral cholesterol derivative ACB played some role in improving liposomes' stability in systemic circulation compared to the conventional PC liposome and the positively charged CAB liposome, with or without PEGylation. In addition, in the case of local drug delivery, the positively charged PEG-liposome not only delivered much more of the drug into the rats' retinas (p < 0.001), but also maintained much longer drug retention time compared to the neutral PEGylated liposomes.

The stability of silver nanoparticles in a model of pulmonary surfactant

The growing use of silver nanoparticles (AgNPs) in consumer products has raised concerns about their potential impact on the environment and human health. Whether AgNPs dissolve and release Ag(+) ions, or coarsen to form large aggregates, is critical in determining their potential toxicity. In this work, the stability of AgNPs in dipalmitoylphosphatidylcholine (DPPC), the major component of pulmonary surfactant, was investigated as a function of pH. Spherical, citrate-capped AgNPs with average diameters of 14 ± 1.6 nm (n = 200) were prepared by a chemical bath reduction. The kinetics of Ag(+) ion release was strongly pH-dependent. After 14 days of incubation in sodium perchlorate (NaClO4) or perchloric acid (HClO4) solutions, the total fraction of AgNPs dissolved varied from ∼10% at pH 3, to ∼2% at pH 5, with negligible dissolution at pH 7. A decrease in pH from 7 to 3 also promoted particle aggregation and coarsening. DPPC (100 mg·L(-1)) delayed the release of Ag(+) ions, but did not significantly alter the total amount of Ag(+) released after two weeks. In addition, DPPC improved the dispersion of the AgNPs and inhibited aggregation and coarsening. TEM images revealed that the AgNPs were coated with a DPPC layer serving as a semipermeable layer. Hence, lung lining fluid, particularly DPPC, can modify the aggregation state and kinetics of Ag(+) ion release of inhaled AgNPs in the lung. These observations have important implications for predicting the potential reactivity of AgNPs in the lung and the environment.

Lipid nanotechnology

Nanotechnology is a multidisciplinary field that covers a vast and diverse array of devices and machines derived from engineering, physics, materials science, chemistry and biology. These devices have found applications in biomedical sciences, such as targeted drug delivery, bio-imaging, sensing and diagnosis of pathologies at early stages. In these applications, nano-devices typically interface with the plasma membrane of cells. On the other hand, naturally occurring nanostructures in biology have been a source of inspiration for new nanotechnological designs and hybrid nanostructures made of biological and non-biological, organic and inorganic building blocks. Lipids, with their amphiphilicity, diversity of head and tail chemistry, and antifouling properties that block nonspecific binding to lipid-coated surfaces, provide a powerful toolbox for nanotechnology. This review discusses the progress in the emerging field of lipid nanotechnology.