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1.
ACS Nano ; 18(13): 9566-9575, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38507585

RESUMO

Throughout history scientists have looked to Nature for inspiration and attempted to replicate intricate complex structures formed by self-assembly. In the context of synthetic supercrystals, achieving such complexity remains a challenge due to the highly symmetric nature of most nanoparticles (NPs). Previous works have shown intricate coupling between the self-assembly of NPs and confinement in templates, such as emulsion droplets (spherical confinement) or tubes (cylindrical confinement). This study focuses on the interplay between anisotropic NP shape and tunable "prismatic confinement" leading to the self-assembly of supercrystals in cavities featuring polygonal cross sections. A multiscale characterization strategy is employed to investigate the orientation and structure of the supercrystals locally and at the ensemble level. Our findings highlight the role of the mold interface in guiding the growth of distinct crystal domains: each side of the mold directs the formation of a monodomain that extends until it encounters another, leading to the creation of grain boundaries. Computer simulations in smaller prismatic cavities were conducted to predict the effect of an increased confinement. Comparison between prismatic and cylindrical confinements shows that flat interfaces are key to orienting the growth of supercrystals. This work shows a method of inducing orientation in plasmonic supercrystals and controlling their textural defects, thus offering insight into the design of functional metasurfaces and hierarchically structured devices.

2.
J Colloid Interface Sci ; 664: 857-867, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38493651

RESUMO

HYPOTHESIS: Imogolite nanotubes (INTs) are unique anisometric particles with monodisperse nanometric diameters. Aluminogermanate double-walled INTs (Ge-DWINTs) are obtained with variable aspect ratios by controlling the synthesis conditions. It thus appears as an interesting model system to investigate how aspect ratio and ionic valence influence the colloidal behavior of highly anisometric rods. EXPERIMENTS: The nanotubes were synthesized by hydrothermal treatment for 5 or 20 days to modify the aspect ratio while the electrostatic interactions were investigated by comparing the colloidal stability in symmetric and asymmetric electrolytes. The phase behavior and their related microstructure were determined by optical observations and small-angle X-ray scattering measurements, coupled with interparticle distance modelling. FINDINGS: We revealed that colloidal suspensions of Ge-DWINTs prepared in NaCl are guided by repulsive double layer forces, undergoing different liquid crystal phase transitions before stiffen into a glass-like state. We found that the microstructure can be rationalized by taking into account the anisometric nature of the particles. By contrast, dispersions prepared with asymmetric electrolytes are governed by strong attractive forces and thus form space-filling gels containing large nanotubes aggregates.

3.
Nanoscale ; 16(12): 6053-6067, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38421016

RESUMO

Mesoporous systems are ubiquitous in membrane science and applications due to their high internal surface area and tunable pore size. A new synthesis pathway of hydrolytic ionosilica films with mesopores formed by ionic liquid (IL) templating is proposed and compared with the traditional non-hydrolytic strategy. For both pathways, the multi-scale formation of pores has been studied as a function of IL content, combining the results of thermogravimetric analysis (TGA), nitrogen sorption, and small-angle X-ray scattering (SAXS). The combination of TGA and nitrogen sorption provides access to ionosilica and pore volume fractions, with contributions of meso- and macropores. We then elaborate an original and quantitative geometrical model to analyze the SAXS data based on small spheres (Rs = 1-2 nm) and cylinders (Lcyl = 10-20 nm) with radial polydispersity provided by the nitrogen sorption isotherms. As a result, we found that for a given incorporation of a templating IL, both synthesis pathways produce very similar pore geometries, but the better incorporation efficacy of the new hydrolytic films provides higher mesoporosity. Our combined study provides a coherent view of mesopore geometry, and thereby an optimization pathway of porous ionic membranes in terms of accessible mesoporosity contributing to the specific surface. Possible applications include electrolyte membranes with improved ionic properties, e.g., in fuel cells and batteries, as well as molecular storage.

4.
Int J Pharm ; 651: 123723, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38110013

RESUMO

Although amphiphilic cyclodextrin derivatives (ACDs) serve as valuable building blocks for nanomedicine formulations, their widespread production still encounters various challenges, limiting large-scale manufacturing. This work focuses on a robust alternative pathway using mineral base catalysis to transesterify ß-cyclodextrin with long-chain vinyl esters, yielding ACD with modular and controlled hydrocarbon chain grafting. ACDs with a wide range of degrees of substitution (DS) were reliably synthesized, as indicated by extensive physicochemical characterization, including MALDI-TOF mass spectrometry. The influence of various factors, including the type of catalyst and the length of the hydrocarbon moiety of the vinyl ester, was studied in detail. ACDs were assessed for their ability to form colloidal suspensions by nanoprecipitation, with or without PEGylated phospholipid. Small-angle X-ray scattering and cryo-electron microscopy revealed the formation of nanoparticles with distinct ultrastructures depending on the DS: an onion-like structure for low and very high DS, and reversed hexagonal organization for DS between 4.5 and 6.1. We confirmed the furtivity of the PEGylated versions of the nanoparticles through complement activation experiments and that they were well tolerated in-vivo on a zebrafish larvae model after intravenous injection. Furthermore, a biodistribution experiment showed that the nanoparticles left the bloodstream within 10 h after injection and were phagocytosed by macrophages.


Assuntos
Ciclodextrinas , Nanopartículas , Animais , Ciclodextrinas/química , Microscopia Crioeletrônica/métodos , Distribuição Tecidual , Peixe-Zebra , Nanopartículas/química , Ésteres , Hidrocarbonetos , Polietilenoglicóis
5.
Food Res Int ; 165: 112496, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36869506

RESUMO

High consumption of plant sterols reduces the risk of cardiovascular diseases in humans and provides health benefits. Increasing the amount of plant sterols in the diet is therefore necessary to reach the recommended daily dietary intake. However, food supplementation with free plant sterols is challenging because of their low solubility in fats and water. The objectives of this study were to investigate the capacity of milk-sphingomyelin (milk-SM) and milk polar lipids to solubilise ß-sitosterol molecules in bilayer membranes organised as vesicles called sphingosomes. The thermal and structural properties of milk-SM containing bilayers composed of various amounts of ß-sitosterol were examined by differential scanning calorimetry (DSC) and temperature-controlled X-ray diffraction (XRD), the molecular interactions were studied using the Langmuir film technique, the morphologies of sphingosomes and ß-sitosterol crystals were observed by microscopy. We showed that the milk-SM bilayers devoid of ß-sitosterol exhibited a gel to fluid Lα phase transition for Tm = 34.5 °C and formed facetted spherical sphingosomes below Tm. The solubilisation of ß-sitosterol within milk-SM bilayers induced a liquid-ordered Lo phaseabove 25 %mol (1.7 %wt) ß-sitosterol and a softening of the membranes leading to the formation of elongated sphingosomes. Attractive molecular interactions revealed a condensing effect of ß-sitosterol on milk-SM Langmuir monolayers. Above 40 %mol (25.7 %wt) ß-sitosterol, partitioning occured with the formation of ß-sitosterol microcrystals in the aqueous phase. Similar results were obtained with the solubilization of ß-sitosterol within milk polar lipid vesicles. For the first time, this study highlighted the efficient solubilization of free ß-sitosterol within milk-SM based vesicles, which opens new market opportunities for the formulation of functional foods enriched in non-crystalline free plant sterols.


Assuntos
Leite , Fitosteróis , Humanos , Animais , Esfingomielinas , Sitosteroides
6.
Pharmaceutics ; 15(2)2023 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-36839701

RESUMO

In this study, the interplay among the phospholipid 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) as a model membrane, the nonsteroidal anti-inflammatory drug naproxen, and the saponin ß-aescin are investigated. The naproxen amount was fixed to 10 mol%, and the saponin amount varies from 0.0 to 1.0 mol%. Both substances are common ingredients in pharmaceutics; therefore, it is important to obtain deeper knowledge of their impact on lipid membranes. The size and properties of the DMPC model membrane upon naproxen and aescin addition were characterized with differential scanning calorimetry (DSC), small- and wide-angle X-ray scattering (SAXS, WAXS), and photon correlation spectroscopy (PCS) in a temperature-dependent study. The interaction of all substances was dependent on the lipid phase state, which itself depends on the lipid's main phase transition temperature Tm. The incorporation of naproxen and aescin distorted the lipid membrane structure and lowers Tm. Below Tm, the DMPC-naproxen-aescin mixtures showed a vesicle structure, and the insertion of naproxen and aescin influenced neither the lipid chain-chain correlation distance nor the membrane thickness. Above Tm, the insertion of both molecules instead induced the formation of correlated bilayers and a decrease in the chain-chain correlation distance. The presented data clearly confirm the interaction of naproxen and aescin with DMPC model membranes. Moreover, the incorporation of both additives into the model membranes is evidenced.

7.
Biomacromolecules ; 24(1): 33-42, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36576429

RESUMO

Controlling the viscoelastic properties of hydrogels is a challenge for many applications. Low molecular weight gelators (LMWGs) like bile salts and glycolipids and biopolymers like chitosan and alginate are good candidates for developing fully biobased hybrid hydrogels that combine the advantages of both components. Biopolymers lead to enhanced mechanics, while LMWGs add functionality. In this work, hybrid hydrogels are composed of biopolymers (gelatin, chitosan, and alginate) and microbial glycolipid bioamphiphiles, known as biosurfactants. Besides their biocompatibility and natural origin, bioamphiphiles can present chameleonic behavior, as pH and ions control their phase diagram in water around neutrality under strongly diluted conditions (<5 wt%). The glycolipid used in this work behaves like a surfactant (micellar phase) at high pH or like a phospholipid (vesicle phase) at low pH. Moreover, at neutral-to-alkaline pH in the presence of calcium, it behaves like a gelator (fiber phase). The impact of each of these phases on the elastic properties of biopolymers is explored by means of oscillatory rheology, while the hybrid structure is studied by small angle X-ray scattering. The micellar and vesicular phases reduce the elastic properties of the hydrogels, while the fiber phase has the opposite effect; it enhances the hydrogel's strength by forming an interpenetrated biopolymer-LMWG network.


Assuntos
Quitosana , Hidrogéis , Hidrogéis/química , Quitosana/química , Fase S , Biopolímeros/química , Alginatos/química , Glicolipídeos/química
8.
Soft Matter ; 19(3): 366-377, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36508178

RESUMO

Low-molecular weight gelators (LMWGs) are small molecules (Mw < ∼1 kDa), which form self-assembled fibrillar network (SAFiN) hydrogels in water. A great majority of SAFiN gels are described by an entangled network of self-assembled fibers, in analogy to a polymer in a good solvent. Here, fibrillation of a biobased glycolipid bolaamphiphile is triggered by Ca2+ or Ag+ ions which are added to its diluted micellar phase. The resulting SAFiN, which forms a hydrogel above 0.5 wt%, has a "nano-fishnet" structure, characterized by a fibrous network of both entangled fibers and ß-sheet-like rafts, generally observed for silk fibroin, actin hydrogels or mineral imogolite nanotubes, but generally not known for SAFiN. This work focuses on the strength of the SAFIN gels, their fast recovery after applying a mechanical stimulus (strain) and their unusual resistance to temperature, studied by coupling rheology to small angle X-ray scattering (rheo-SAXS) using synchrotron radiation. The Ca2+-based hydrogel maintains its properties up to 55 °C, while the Ag+-based gel shows a constant elastic modulus up to 70 °C, without the appearance of any gel-to-sol transition temperature. Furthermore, the glycolipid is obtained by fermentation from natural resources (glucose and rapeseed oil), thus showing that naturally engineered compounds can have unprecedented properties, when compared to the wide range of chemically derived amphiphiles.


Assuntos
Glicolipídeos , Hidrogéis , Conformação Proteica em Folha beta , Espalhamento a Baixo Ângulo , Temperatura , Glicolipídeos/química , Difração de Raios X , Hidrogéis/química , Reologia
9.
J Colloid Interface Sci ; 633: 566-574, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36470137

RESUMO

From the 15th century onwards, painters began to treat their oils with lead compounds before grinding them with pigments. Such a treatment induces the partial hydrolysis of the oil triglycerides and the formation of lead soaps, which significantly modify the rheological properties of the oil paint. Organization at the supramolecular scale is thus expected to explain these macroscopic changes. Synchrotron Rheo-SAXS (Small Angle X-ray Scattering) measurements were carried out on lead-treated oils, with different lead contents. We can now propose a full picture of the relationship between structure and rheological properties of historical saponified oils. At rest, lead soaps in oil are organized as lamellar phases with a characteristic period of 50 Å. Under shear, the loss of viscoelastic properties can be linked to the modification of this organization. Continuous shear resulted in a preferential and reversible orientation of the lamellar domains which increased with the concentration of lead soaps. The parallel orientation predominates over the entire shear range (0-1000 s-1). Conversely, oscillatory shear coiled the lamellae into cylinders that oriented themselves vertically in the rheometer cell. This is the first report of such a vertical cylindrical structure obtained under shear from lamellae.


Assuntos
Óleos , Sabões , Difração de Raios X , Espalhamento a Baixo Ângulo
10.
Biomacromolecules ; 24(1): 19-32, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36573937

RESUMO

Hydrogels are widespread soft materials, which can be used in a wide range of applications. The control over the viscoelastic properties of the gel is of paramount importance. Ongoing environmental issues have raised the consumer's concern toward the use of more sustainable materials, including hydrogels. However, are greener materials compatible with high functionality? In a safe-by-design approach, this work demonstrates that functional hydrogels with in situ responsivity of their elastic properties by external stimuli can be developed from entirely "sustainable" components, a biobased amphiphile and biopolymers (gelatin, chitosan, and alginate). The bioamphiphile is a stimuli-responsive glycolipid obtained by microbial fermentation, which can self-assemble into fibers, but also micelles or vesicles, in water under high dilution and by a rapid variation of the stimuli. The elastic properties of the bioamphiphile-/biopolymer-interpenetrated hydrogels can be modulated by selectively triggering the phase transition of the glycolipid and/or the biopolymer inside the gel by mean of temperature or pH.


Assuntos
Quitosana , Hidrogéis , Hidrogéis/química , Biopolímeros/química , Quitosana/química , Alginatos/química , Água
11.
J Colloid Interface Sci ; 630(Pt A): 355-364, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36257137

RESUMO

Aggregates of charged metal particles obtained by electrostatic coupling with a compound of opposite charge in the vicinity of the net zero charge ratio are of interest in the field of plasmonics because the inter-particle distance is minimal, which favours plasmonic coupling. However, these structures present a low colloidal stability limiting the development of applications. In this article we show that globally neutral aggregates formed by electrostatic complexation of citrate-stabilized gold particles and a quaternized chitosan (i.e., polycation) around the net zero charge ratio could be stabilized at a nanometric size by the subsequent addition of polyelectrolyte chains. Furthermore, the sign of the charge carried by the stabilizing chains determines the sign of the global charge carried by the stabilized complexes. The stabilization is demonstrated in saline environment on a broad pH range as well as in a cell culture media over periods of several days. Contrarily to stabilization by charged particles, our stabilized complexes are found to retain their initial characteristics (i.e. shape, size, internal structure and optical properties) after stabilization. Hence, the plasmonic coupling allows to maximize the optical absorption around the 800 nm wavelength at which the lasers used for thermoplasmonic and surface enhanced Raman scattering analysis operate.


Assuntos
Quitosana , Nanopartículas Metálicas , Polieletrólitos , Ouro , Tamanho da Partícula , Quitosana/química , Íons
12.
Langmuir ; 38(48): 14563-14573, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36395196

RESUMO

Bottom-up strategies for the production of well-defined nanostructures often rely on the self-assembly of anisotropic colloidal particles (nanowires and nanosheets). These building blocks can be obtained by delamination in a solvent of low-dimensionality crystallites. To optimize particle availability, determination of the delamination mechanism and the different organization stages of anisotropic particles in dispersion is essential. We address this fundamental issue by exploiting a recently developed system of fluorohectorite smectite clay mineral that delaminates in water, leading to colloidal dispersions of single-layer, very large (≈20 µm) clay sheets at high dilution. We show that when the clay crystallites are dispersed in water, they swell to form periodic one-dimensional stacks of fluorohectorite sheets with very low volume fraction (<1%) and therefore huge (≈100 nm) periods. Using optical microscopy and synchrotron X-ray scattering, we establish that these colloidal stacks bear strong similarities, yet subtle differences, with a smectic liquid-crystalline phase. Despite the high dilution, the colloidal stacks of sheets, called colloidal accordions, are extremely robust mechanically and can persist for years. Moreover, when subjected to AC electric fields, they rotate as solid bodies, which demonstrates their outstanding internal cohesion. Furthermore, our theoretical model captures the dependence of the stacking period on the dispersion concentration and ionic strength and explains, invoking the Donnan effect, why the colloidal accordions are kinetically stable over years and impervious to shear and Brownian motion. Because our model is not system specific, we expect that similar colloidal accordions frequently appear as an intermediate state during the delamination process of two-dimensional crystals in polar solvents.

13.
Nanomaterials (Basel) ; 12(9)2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35564238

RESUMO

Multi-responsive nanomaterials based on the self-limited assembly of plasmonic nanoparticles are of great interest due to their widespread employment in sensing applications. We present a thorough investigation of a hybrid nanomaterial based on the protein-mediated aggregation of gold nanoparticles at varying protein concentration, pH and temperature. By combining Small Angle X-ray Scattering with extinction spectroscopy, we are able to frame the morphological features of the formed fractal aggregates in a theoretical model based on patchy interactions. Based on this, we established the main factors that determine the assembly process and their strong correlation with the optical properties of the assemblies. Moreover, the calibration curves that we obtained for each parameter investigated based on the extinction spectra point out to the notable flexibility of this nanomaterial, enabling the selection of different working ranges with high sensitivity. Our study opens for the rational tuning of the morphology and the optical properties of plasmonic assemblies to design colorimetric sensors with improved performances.

14.
Adv Mater ; 34(21): e2200883, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35324025

RESUMO

Pentagonal packing is a long-standing issue and a rich mathematical topic, brought to the fore by recent progress in nanoparticle design. Gold pentagonal bipyramids combine fivefold symmetry and anisotropy and their section varies along the length. In this work, colloidal supercrystals of pentagonal gold bipyramids are obtained in a compact arrangement that generalizes the optimal packing of regular pentagons in the plane. Multimodal investigations reveal a two-particle unit cell with triclinic symmetry, a lower symmetry than that of the building blocks. Monte Carlo computer simulations show that this lattice achieves the densest possible packing. Going beyond pentagons, further simulations show an odd-even effect of the number of sides on the packing: odd-sided bipyramids are non-centrosymmetric and require the double-lattice arrangement to recover inversion symmetry. The supercrystals display a facet-dependent optical response that is promising for sensing, metamaterials applications, and for fundamental studies of self-assembly processes.

15.
Small Methods ; 5(7): e2100168, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34927996

RESUMO

FSI- -based ionic liquids (ILs) are promising electrolyte candidates for long-life and safe lithium metal batteries (LMBs). However, their practical application is hindered by sluggish Li+ transport at room temperature. Herein, it is shown that additions of bis(2,2,2-trifluoroethyl) ether (BTFE) to LiFSI-Pyr14 FSI ILs can effectively mitigate this shortcoming, while maintaining ILs' high compatibility with lithium metal. Raman spectroscopy and small-angle X-ray scattering indicate that the promoted Li+ transport in the optimized electrolyte, [LiFSI]3 [Pyr14 FSI]4 [BTFE]4 (Li3 Py4 BT4 ), originates from the reduced solution viscosity and increased formation of Li+ -FSI- complexes, which are associated with the low viscosity and non-coordinating character of BTFE. As a result, Li/LiFePO4 (LFP) cells using Li3 Py4 BT4 electrolyte reach 150 mAh g-1 at 1 C rate (1 mA cm-2 ) and a capacity retention of 94.6% after 400 cycles, revealing better characteristics with respect to the cells employing the LiFSI-Pyr14 FSI (operate only a few cycles) and commercial carbonate (80% retention after only 218 cycles) electrolytes. A wide operating temperature (from -10 to 40 °C) of the Li/Li3 Py4 BT4 /LFP cells and a good compatibility of Li3 Py4 BT4 with LiNi0.5 Mn0.3 Co0.2 O2 (NMC532) are demonstrated also. The insight into the enhanced Li+ transport and solid electrolyte interphase characteristics suggests valuable information to develop IL-based electrolytes for LMBs.

16.
Nanoscale ; 13(34): 14572, 2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34473189

RESUMO

Correction for 'Galenic Lab-on-a-Chip concept for lipid nanocapsules production' by Nicolas Rolley et al., Nanoscale, 2021, 13, 11899-11912, DOI: 10.1039/D1NR00879J.

17.
J Colloid Interface Sci ; 604: 358-367, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34273780

RESUMO

We investigate the organisation of clay nanoplatelets within a hydrogel based on modified ionenes, cationic polyelectrolytes forming physically crosslinked hydrogels induced by hydrogen bonding and π-π stacking. Combination of small angle X-ray and neutron scattering (SAXS, SANS) reveals the structure of the polyelectrolyte network as well as the organisation of the clay additives. The clay-free hydrogel network features a characteristic mesh-size between 20 and 30 nm, depending on the polyelectrolyte concentration. Clay nanoplatelets inside the hydrogel organise in a regular face-to-face stacking manner, with a large repeat distance, following rather closely the hydrogel mesh-size. The presence of the nanoplatelets does not modify the hydrogel mesh size. Further, the clay-compensating counterions (Na+, Ca2+ or La3+) and the clay type (montmorillonite, beidellite) both have a significant influence on nanoplatelet organisation. The degree of nanoplatelet ordering in the hydrogel is very sensitive to the negative charge location on the clay platelet (different for each clay type). Increased nanoplatelet ordering leads to an improvement of the elastic properties of the hydrogel. On the contrary, the presence of dense clay aggregates (tactoids), induced by multi-valent clay counterions, destroys the hydrogel network as seen by the reduction of the elastic modulus of the hydrogel.


Assuntos
Hidrogéis , Argila , Polieletrólitos , Espalhamento a Baixo Ângulo , Difração de Raios X
18.
J Phys Condens Matter ; 33(40)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34237714

RESUMO

Mixtures of polymer-colloid hybrids such as star polymers and microgels with non-adsorbing polymeric additives have received a lot of attention. In these materials, the interplay between entropic forces and softness is responsible for a wealth of phenomena. By contrast, binary mixtures where one component can adsorb onto the other one have been far less studied. Yet real formulations in applications often contain low molecular weight additives that can adsorb onto soft colloids. Here we study the microstructure and rheology of soft nanocomposites made of surfactants and microgels using linear and nonlinear rheology, SAXS experiments, and cryo-TEM techniques. The results are used to build a dynamical state diagram encompassing various liquid, glassy, jammed, metastable, and reentrant liquid states, which results from a subtle interplay between enthalpic, entropic, and kinetic effects. We rationalize the rheological properties of the nanocomposites in each domain of the state diagram, thus providing exquisite solutions for designing new rheology modifiers at will.

19.
Nanoscale ; 13(27): 11899-11912, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34190298

RESUMO

The continuous production of drug delivery systems assisted by microfluidics has drawn a growing interest because of the high reproducibility, low batch-to-batch variations, narrow and controlled particle size distributions and scale-up ease induced by this kind of processes. Besides, microfluidics offers opportunities for high throughput screening of process parameters and the implementation of process characterization techniques as close to the product as possible. In this context, we propose to spotlight the GALECHIP concept through the development of an instrumented microfluidic pilot considered as a Galenic Lab-on-a-Chip to formulate nanomedicines, such as lipid nanocapsules (LNCs), under controlled process conditions. In this paper we suggest an optimal rational development in terms of chip costs and designs. First, by using two common additive manufacturing techniques, namely fused deposition modelling and multi-jet modelling to prototype customized 3D microfluidic devices (chips and connectors). Secondly, by manufacturing transparent Silicon (Si)/Glass chips with similar channel geometries but obtained by a new approach of deep reactive ion etching (DRIE) technology suitable with in situ small angle X-ray scattering characterizations. LNCs were successfully produced by a phase inversion composition (PIC) process with highly monodispersed sizes from 25 nm to 100 nm and formulated using chips manufactured by 3D printing and DRIE technologies. The transparent Si/Glass chip was also used for the small angle X-ray scattering (SAXS) analysis of the LNC formulation with the PIC process. The 3D printing and DRIE technologies and their respective advantages are discussed in terms of cost, easiness to deploy and process developments in a GALECHIP point of view.


Assuntos
Dispositivos Lab-On-A-Chip , Nanocápsulas , Lipídeos , Reprodutibilidade dos Testes , Espalhamento a Baixo Ângulo , Difração de Raios X
20.
Front Cell Dev Biol ; 9: 617984, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33644054

RESUMO

Structural properties of plasmenyl-glycerophospholipids (plasmalogens) have been scarcely studied for plasmalogens with long polyunsaturated fatty acid (PUFA) chains, despite of their significance for the organization and functions of the cellular membranes. Elaboration of supramolecular assemblies involving PUFA-chain plasmalogens in nanostructured mixtures with lyotropic lipids may accelerate the development of nanomedicines for certain severe pathologies (e.g., peroxisomal disorders, cardiometabolic impairments, and neurodegenerative Alzheimer's and Parkinson's diseases). Here, we investigate the spontaneous self-assembly of bioinspired, custom-produced docosapentaenoyl (DPA) plasmenyl (ether) and ester phospholipids in aqueous environment (pH 7) by synchrotron small-angle X-ray scattering (SAXS) and cryogenic transmission electron microscopy (cryo-TEM). A coexistence of a liquid crystalline primitive cubic Im3m phase and an inverted hexagonal (HII) phase is observed for the DPA-ethanolamine plasmalogen (C16:1p-22:5n6 PE) derivative. A double-diamond cubic Pn3m phase is formed in mixed assemblies of the phosphoethanolamine plasmalogen (C16:1p-22:5n6 PE) and monoolein (MO), whereas a coexistence of cubic and lamellar liquid crystalline phases is established for the DPA-plasmenyl phosphocholine (C16:1p-22:5n6 PC)/MO mixture at ambient temperature. The DPA-diacyl phosphoinositol (22:5n6-22:5n6 PI) ester lipid displays a propensity for a lamellar phase formation. Double membrane vesicles and multilamellar onion topologies with inhomogeneous distribution of interfacial curvature are formed upon incorporation of the phosphoethanolamine plasmalogen (C16:1p-22:5n6 PE) into dioleoylphosphocholine (DOPC) bilayers. Nanoparticulate formulations of plasmalogen-loaded cubosomes, hexosomes, and various multiphase cubosome- and hexosome-derived architectures and mixed type nano-objects (e.g., oil droplet-embedding vesicles or core-shell particles with soft corona) are produced with PUFA-chain phospholipids and lipophilic antioxidant-containing membrane compositions that are characterized by synchrotron SAXS and cryo-TEM imaging. The obtained multiphase nanostructures reflect the changes in the membrane curvature induced by the inclusion of DPA-based PE and PC plasmalogens, as well as DPA-PI ester derivative, and open new opportunities for exploration of these bioinspired nanoassemblies.

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