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The use of conductive hydrogels in flexible electronics has gained significant attention in recent years. However, the performance of traditional hydrogels is often hindered by dehydration at elevated temperatures and structural rigidity when frozen at low temperatures. In this study, we developed a double-network hydrogel consisting of ionically crosslinked pectin and covalently crosslinked polyacrylamide (PAAm) networks. Scanning Electron Microscopy (SEM) analysis revealed a highly interconnected and porous microstructure, which contributes to the enhanced mechanical strength and flexibility of the hydrogel. Through a solvent exchange process, the PAAm-pectin hydrogel was transformed into an organo-gel by immersing it in a binary solvent system of ethylene glycol and water. The incorporation of ethylene glycol significantly improved the hydrogel's temperature tolerance, imparting superior anti-freezing and anti-drying properties. The resulting organogel exhibited remarkable transparency, excellent flexibility, and sustained ionic conductivity even at temperatures as low as −40°C. These attributes highlight the PAAm-pectin organogel as a promising candidate for next-generation flexible electronic devices, where performance stability under extreme conditions is essential. [ABSTRACT FROM AUTHOR]

Novel polysaccharide gels were prepared by a covalent crosslinking of xylan and cellulose derivatives through Diels–Alder (DA) cycloaddition. For this purpose, polysaccharide carbamates were synthesized through a modular approach that incorporated either furfuryl or maleimide moieties for DA reaction as well as solubilizing tertiary amino or quaternary ammonium moieties that facilitated water solubility. All compounds were fully characterized with respect to degrees of substitution (DS) and molecular structures. Organogels and hydrogels were prepared by selective covalent crosslinking of the derivatives through DA reaction. The gelation process was monitored by rheological measurements to evaluate the kinetics with respect to different crosslinking conditions and the gels were characterized with respect to mechanical properties as well as drying and reswelling behavior. Moreover, several side reactions that occurred during the gelation were identified and it was possible to adjust the molecular structure accordingly to avoid these issues. Thus, it was possible to obtain novel polysaccharide-based organogels and hydrogels that displayed thermoreversible behavior, as well as good mechanical stability and re-swelling capacities. [ABSTRACT FROM AUTHOR]

Organogels are less explored toward on‐sink flexible and stretchable electronics compared to hydrogels, due to the challenges in simultaneously achieving biocompability, satisfactory mechanical properties, environmental‐adaptive adhesion capability, and fast stimuli‐response. Herein, it is shown that a boronate ester polymer organogel with dynamic covalent and hydrogen bonds formed between the polymer networks and organic solvents meets all the above requirements. This is achieved through the gelation of a polymer bearing with boronic acid, imidazolium salt, and amide groups (named QBAM) in ethylene glycol (EG). The strong interactions between the polymer chains and the EG not only improve the toughness of QBAMs, but also inhibit the volatilization of EG, leading to a wide temperature (−10 to 190 °C) adaptability. Due to the abundant hydrogen bonds and electrostatic interaction, QBAM organogels are highly adhesive to a variety of substrates. The presence of imidazolium salt endows QBAM organogels with promising ionic conductivity. Strain sensors fabricated with QBAM organogels fit well on human skin and exhibit the advantages of high strain sensitivity (GF = 9.049), fast response (≈60.4 ms), good cyclic stability, and broaden temperature adaptability. This work opens up a new avenue for the design of multifunctional and biocompatible organogels for on‐skin devices. [ABSTRACT FROM AUTHOR]

Organogels are polymer networks extended by a liquid organic phase, offering a wide range of properties due to the many combinations of polymer networks, solvents, and shapes achievable through 3D printing. However, current printing methods limit solvent choice and composition, which in turn limits organogels' properties, applications, and potential for innovation. As a solution, a method for solvent‐independent printing of 3D organogel structures is presented. In this method, the printing step is decoupled from the choice of solvent, allowing access to the full spectrum of solvent diversity, thereby significantly expanding the range of achievable properties in organogel structures. With no changes to the polymer network, the 3D geometry, or the printing methodology itself, the choice of solvent alone is shown to have an enormous impact on organogel properties. As demonstrated, it can modulate the thermo‐mechanical properties of the organogels, both shifting and extending their thermal stability range to span from ‐30 to over 100 °C. The choice of solvent can also transition the organogels from highly adhesive to extremely slippery. Finally, the method also improves the surface smoothness of prints. Such advances have potential applications in soft robotics, actuators, and sensors, and represent a versatile approach to expanding the functionality of 3D‐printed organogels. [ABSTRACT FROM AUTHOR]

Since the last decade, the need for deformable electronics exponentially increased, requiring adaptive energy storage systems, especially batteries and supercapacitors. Thus, the conception and elaboration of new deformable electrolytes becomes more crucial than ever. Among diverse materials, gel polymer electrolytes (hydrogels, organogels, and ionogels) remain the most studied thanks to the ability to tune the physicochemical and mechanical properties by changing the nature of the precursors, the type of interactions, and the formulation. Nevertheless, the exploitation of this category of electrolyte as a possible commercial product is still restrained, due to different issues related to the nature of the gels (ionic conductivity, evaporation of filling solvent, toxicity, etc.). Therefore, this review aims to resume different strategies to tailor the properties of the gel polymer electrolytes as well as to provide recent advancements in the field toward the elaboration of deformable batteries and supercapacitors. [ABSTRACT FROM AUTHOR]

Abstract An innovative green organogel was designed to simultaneously tackle inorganic compounds (i.e., iron corrosion) and organic substances (i.e., acrylic coatings) as undesired materials possibly present on the surface of altered indoor metal artworks. Poly-3-hydroxybutyrate (PHB), ethyl lactate (EL), and deferoxamine B (DFO) were employed in the formulation as thickening agent, organic solvent, and complexing agent, respectively, aiming to propose a sustainable and less harmful chemical cleaning method for metal care. The components were selected because they are bio-sourced, renewable, biodegradable, and non- or low-toxic materials. A multi-modal protocol of analysis was carried out to characterise the newly designed PHB-EL-DFO organogel. The cleaning performance of the novel formulation was assessed on mild steel mock-ups presenting both corrosion and organic coating to be removed. The conducted multi-analytical approach verified that the PHB-EL-DFO gel was able to tackle the two undesired materials simultaneously in an adjustable and easy-to-use way thanks to a modular application.

An innovative green organogel was designed to simultaneously tackle inorganic compounds (i.e., iron corrosion) and organic substances (i.e., acrylic coatings) as undesired materials possibly present on the surface of altered indoor metal artworks. Poly-3-hydroxybutyrate (PHB), ethyl lactate (EL), and deferoxamine B (DFO) were employed in the formulation as thickening agent, organic solvent, and complexing agent, respectively, aiming to propose a sustainable and less harmful chemical cleaning method for metal care. The components were selected because they are bio-sourced, renewable, biodegradable, and non- or low-toxic materials. A multi-modal protocol of analysis was carried out to characterise the newly designed PHB-EL-DFO organogel. The cleaning performance of the novel formulation was assessed on mild steel mock-ups presenting both corrosion and organic coating to be removed. The conducted multi-analytical approach verified that the PHB-EL-DFO gel was able to tackle the two undesired materials simultaneously in an adjustable and easy-to-use way thanks to a modular application. [ABSTRACT FROM AUTHOR]

A possibility of isolating gels from organosols of silica by high-speed centrifugation is demonstrated. Organosols of Ag, Au, and CdS nanoparticles (NPs) synthesized in reverse emulsions of AOT are used as the staining additives. Porous rough coatings are molded from the gels by the Doctor Blade method followed by drying and thermolysis at 500°C. The obtained coatings are promising for medical and biological, photovoltaic, and photocatalytic applications. [ABSTRACT FROM AUTHOR]

Supramolecular gels were developed by taking advantage of an assembly of small dipeptides containing pyrrolo-pyrazole scaffolds. The dipeptides were prepared through a robust and ecofriendly synthetic approach from the commercially available starting materials of diazoalkanes and maleimides. By playing with the functionalization of the scaffold, the choice of the natural amino acid, and the stereochemistry, we were able to obtain phase-selective gels. In particular, one peptidomimetic showed gelation ability and thermoreversibility in aromatic solvents at very low concentrations. Rheology tests showed a typical viscoelastic solid profile, indicating the formation of strong gels that were stable under high mechanical deformation. NMR studies were performed, allowing us to determine the conformational and stereochemical features at the base of the supramolecular interactions. [ABSTRACT FROM AUTHOR]

It was first discovered that the excellent gelation ability of tea saponin can be obtained by introducing long-chain alkyl groups of dodecanoyl chloride into the glycosyl portion with direct esterification. The modified dodecanoyl chloride–tea saponin (DC-TS) was successfully synthesized and characterized with NMR, MS, and FT-IR. The tests showed that the long-chain alkyl group was successfully introduced. Combined with SEM and X-ray diffraction patterns, we found that the stable lamellar shape gels of DC-TS were formed in a variety of solvents. More interestingly, organogel was also obtained by adjusting good solvent and poor solvent as mixed solvent. It is worth noting that the driving force of organogels is the combination of hydrogen bonding and the hydrophobic interaction of the introduced alkyl chains with the rigid backbone of pentacyclic triterpenes. The modified tea saponin, a natural green surfactant, was discovered to have gelation properties, which has broadened tea saponin's scope of application and made it more promising. [ABSTRACT FROM AUTHOR]

Patterning diversified properties and surface structure of polymer materials are of great importance toward their potential in biology, optics, and electronics. However, achieving both the patternability of stiffness and microstructure in a reconfigurable manner remains challenging. Here, we prepare amphigels crosslinked by dynamic disulfide bonds, which can be reversibly swollen by immiscible water or liquid paraffin. In the paraffingel form, the materials exhibited a high modulus of 130 MPa due to densified hydrogen bonds. Whereas swollen by water, the modulus fell over two orders of magnitude owing to the destruction of the hydrogen bonds. Via regionalized swelling of the solvents, well‐controlled and rewritable soft/stiff mechanical patterns can be created. On the other hand, the dynamic exchange of the disulfide crosslinking enables mechanophoto patterning to fabricate sophisticated macrogeometries and microstructures. The reconfigurable stiffness‐structure patterning can be manipulated orthogonally, which will create more application opportunities beyond conventional hydrogels and organogels. [ABSTRACT FROM AUTHOR]

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Biomimetic damping materials have emerged as promising candidates for various applications due to their ability to mimic the exceptional damping properties observed in biological systems. This review provides a comprehensive overview of recent advances in the field of biomimetic damping gel materials. The conceptual framework of biomimetic damping materials is discussed, the synthesis methods inspired by biological principles are elucidated, and key considerations in material selection are highlighted. The latest research findings on the mechanical properties, biocompatibility and practical applications of these materials are synthesized and insights into the future directions of biomimetic damping gel materials are offered.

Background: Curcumin (CUR) and its derivatives have shown a wide variety of biological activities, such as anti-oxidant, anti-inflammatory, anti-tumor, antimicrobial and antiparasitic effects as well as for the treatment of skin diseases. Due to its physico-chemical limitations such as low aqueous solubility and low bioavailability, we developed curcumin organogel as a topical delivery system to overcome those limitations. The12-hydroxystearic acid (12-HSA) is well known as a low-molecular-weight organogelators (LMOGs) capable of gelling an organic liquid phase. Different concentrations of (12-HSA) in triacetin with 50 mg CUR were gelled and applied for various examinations: tabletop rheology, oil binding capacity, pH measurement, spreadability, in vitro drug release, antibacterial activity and oscillatory rheology studies. The results revealed that the organogels transition temperatures from solid to liquid were greater than the normal body temperature, this helped the organogels keep their shape; they had good spreadability,and the organogels pH levels were within the safe range for the skin . In vitro release data showed that 4% 12HSA+5%CUR +TA (4TA) gave us 100% release after 6 hours. The selected 4TA illustrated good viscoelastic properties in the amplitude sweep test and a frequency-independent as seen in the frequency sweep test. CUR has good antibacterial action against Staphylococcus aureus; Streptococcus pyrogen, Proteus mirabilis, and Escherichia coli, which prevail at the site of wound injury as this pointed out that 4TA organogel can be used for topical wound healing.

Abstract Patterning diversified properties and surface structure of polymer materials are of great importance toward their potential in biology, optics, and electronics. However, achieving both the patternability of stiffness and microstructure in a reconfigurable manner remains challenging. Here, we prepare amphigels crosslinked by dynamic disulfide bonds, which can be reversibly swollen by immiscible water or liquid paraffin. In the paraffingel form, the materials exhibited a high modulus of 130 MPa due to densified hydrogen bonds. Whereas swollen by water, the modulus fell over two orders of magnitude owing to the destruction of the hydrogen bonds. Via regionalized swelling of the solvents, well‐controlled and rewritable soft/stiff mechanical patterns can be created. On the other hand, the dynamic exchange of the disulfide crosslinking enables mechanophoto patterning to fabricate sophisticated macrogeometries and microstructures. The reconfigurable stiffness‐structure patterning can be manipulated orthogonally, which will create more application opportunities beyond conventional hydrogels and organogels.

Abstract Given the high content of unsaturated fatty acids that high oleic sunflower oil has and thinking in terms of healthiness and innovation, this study aimed to characterize organogels and to investigate the effect of the addition of organogels in chocolate spreads to reduce saturated fatty acids (SFA). The characterization of the organogels was carried out in terms of solids fat content (SFC), crystallization kinetics, thermal behavior, polymorphism, microstructure, hardness, and rheological properties. The organogels analysed showed 5.22% to 6.20% solids at 10 °C, melted at 45 °C, and dropped to < 2.34% at 37.5 °C. Induction time was 4 to 8 minutes, with max solids at 2.29% to 4.72%. The melting and crystallization curves could be subdivided into different regions, which reflected the different classes of triacylglycerol present in the organogels. All organogels showed β polymorphism. The average diameter of the organogels was less than 30 μm, thus minimizing the perception of grittiness in the mouth resulting from the lipid phase. Hardness values varied between 3.53 and 4.58 N. The elastic modulus (G’) value was greater than the viscous modulus (G”), indicating the behavior of a solid material. The results of chocolate spreads were characterized by consistency, distribution particle size, rheological properties and dynamic turbidimetry. The range of consistency of spreads ranged from 13.83 to 631.60 gF. All chocolate spreads formulated with organogels showed particle size between 14.59 and 46.23 µm at index d 0.5 and d 0.9, respectively. As for the rheological parameters, the G' value was observed superior to G”, indicating properties of solid materials. The chocolate spreads with organogels analyzed showed characteristic stability. There was no exudation of liquid oil in the stabilization period for 36 days, thus the chocolate spreads showed a predominant elastic behavior. This characterization proves to be fundamental for the reformulation of products in terms of greater healthiness.

The visualization and analysis of organic solvents using fluorescent sensors are crucial, given their association with environmental safety and human health. Conventional fluorescent sensors are typically single‐use sensors and they often require sophisticated measurement instruments, which limits their practical and diverse applications. Herein, we develop solvatochromic nitrogen and sulfur codoped carbon dots (NS‐CDs)‐based organogel sensors that display color changes in response to different solvents. NS‐CDs are synthesized using a solvothermal method to produce monodispersed particles with exceptional solubility in various organic solvents. NS‐CDs exhibit distinct photoluminescent emission spectra that correlate with the solvent polarity, and the solvent‐dependent photoluminescent mechanism is investigated in detail. To highlight the potential application of solvatochromic NS‐CDs, portable and low‐cost NS‐CDs‐embedded organogel sensors are fabricated. These sensors exhibit highly robust solvatochromic performance despite repeated solvent switches, thus ensuring consistent and reliable measurements in practical applications. This study provides valuable insights into the solvatochromism of carbon dots and opens up new avenues for designing real‐time organic solvent sensing platforms. [ABSTRACT FROM AUTHOR]

In the present work, stable organogels and hydrogels could be formed by dimeric-dehydrocholic acid derivative (DDAD) in different solvents. Compared with the organogels, the hydrogels formed by DDAD were found to be thermal reversible and had higher gel-to-solution transition temperature. The supramolecular structures in the organogels and hydrogels were further studied by using transmission electron microscopy (TEM) and atomic force microscopy (AFM). TEM and AFM images of the supramolecular gels showed that the solvent effects played a crucial role in morphological structures. Specifically, the organogel had a three-dimensional porous network structure. While, the hydrogel had a supramolecular structure made up of long fibers. Fourier transformation infrared spectroscopy (FT-IR) showed that multiple hydrogen bonds among the gelator molecules were the main driving forces in gel formation. On this base, the solvent effects on the gelation abilities and thermal stability were discussed. Thus, the present study provides a solvent-induced self-assembly approach and contributes substantially to the development of the supramolecular gels as soft materials. [ABSTRACT FROM AUTHOR]

Three new thiourea-based thermo-reversible, low molecular weight organogelators (LMOGs) 3-5 have been synthesized using (+)-Dehydroabietylamine (DAA, a tricyclic diterpene) employing DLS (Diterpene-Linker-spacer) strategy. (+) DAA was converted into isothiocynates through a cascade of reactions and cross-coupled with primary amines to furnish thiourea 3-5 with respective spacers. The structures of gelators 3-5 were confirmed through 1H-NMR and 13C-NMR spectroscopy, high-resolution electron spray ionization mass spectrometry (HRESI–MS, positive mode) and FTIR spectroscopy. Gelation potential of gelators 3-5 was investigated through inverted test tube method and sol–gel transition measured by ball-dropping method. The results revealed that unbranched alkyl groups furnish gelation and their gelation ability increases with increasing spacer length. Gelator 5 with dodecyl chain found to be excellent gelator that can gelate hexane (spontaneously), toluene, methanol, ethanol, petrol, and diesel. Morphology of gels was studied though scanning electron microscopy exhibiting fibrillar to lamellar structure with a thickness in the range of 9.5 nm to 5.0 μm with increasing length of spacer. [ABSTRACT FROM AUTHOR]

Two organogelators, CO‐01 and CO‐03, featuring benzimidazole and long‐chain pyridine carboxyamide groups were prepared and their physical properties were fully explored. CO‐01 and CO‐03 are capable of transforming various organic solvents to organogels. The morphologic investigations of these organogels have shown that the supramolecular assemblies, in the forms of fibers and spheres, are readily generated from the aggregates of CO‐01 and CO‐03. The sol–gel interconversion can be readily achieved by tuning the gelator concentration and temperature. By manipulating the redox state of anthraquinone group in CO‐03, the gel–sol transition for the organogels of CO‐03 can be reversibly tuned by either chemical or electrochemical oxidation/reduction reactions. The presence of polarized imidazole and amide N–H groups allows anion‐induced gel collapse. The accompanying colorimetric and ratiometric fluorescent responses of gels CO‐01 and CO‐03 to F− and CN− render these organogelators being sensitive and selective anion probes. [ABSTRACT FROM AUTHOR]

Due to their intrinsic flexibility, tunable conductivity, multiple stimulus‐response, and self‐healing ability, ionic conductive hydrogels have drawn significant attention in flexible/wearable electronics. However, challenges remain because traditional hydrogels inevitably faced the problems of losing flexibility and conductivity because of the inner water loss when exposed to the ambient environment. Besides, the water inside the hydrogel will freeze at the water icing temperatures, making the device hard and fragile. As a promising alternative, organogels have attracted wide attention because they can, to some extent, overcome the above drawbacks. Herein, a kind of organogel ionic conductor (MOIC) by a self‐polymerization reaction is involved, which is super stretchable, anti‐drying, and anti‐freezing. Meanwhile, it can still maintain high mechanical stability after alternately loading/unloading at the strain of 600% for 600 s (1800 cycles). Using this MOIC, high‐performance triboelectric nanogenerator (TENG) is constructed (MOIC‐TENG) to harvest small mechanical energy even the MOIC electrode underwent an extremely low temperature. In addition, multifunctional flexible/wearable sensors (strain sensor, piezoresistive sensor, and tactile sensor) are realized to monitor human motions in real time, and recognize different materials by triboelectric effect. This study demonstrates a promising candidate material for flexible/wearable electronics such as electronic skin, flexible sensors, and human‐machine interfaces. [ABSTRACT FROM AUTHOR]

We demonstrate here a simple approach to integrate photochromic properties with aggregation‐induced emission behavior via supramolecular self‐assembly with the aim to build a new type of photoswitchable materials. We have designed and synthesized two unsymmetrical peptide‐bridged naphthalimide–dithienylethene dyads, each composed of naphthalimide (NI), an alkyl (CH2)n [n=2,8] chain (Cn), a dipeptide of phe‐phe scaffold, and an unsymmetrical dithienylethene (DTE) moiety (NI‐Cn‐pep‐DTE; 6: n=2; 7: n=8). Dyads 6 and 7 show comparable photo‐isomerization speed and rate constant (K) values for cyclization (75 s, K=0.049 s−1 for 6, 65 s, K=0.056 s−1 for 7) and cycloreversion (105 s, K=0.037 s−1 for 6, 100 s, K=0.023 s−1 for 7) accompanied by a noticeable naked‐eye color change from pale yellow (6 o/7 o; open forms) to purple (6 c/7 c; closed forms). Both compounds show considerably high fatigue resistance for at least 45 cycles without loss of sensitivity and compound 7 exhibits fluorescence photoswitching performance in solution, solid state, as well as in gel form through a FRET mechanism. The developed dithienylethene (DTE)‐based material was applied in latent fingerprints (LFPs) and in anti‐counterfeiting technology in a non‐invasive manner. [ABSTRACT FROM AUTHOR]

In this work, a comparative study of the swelling behavior of poly((1,7,7-trimethyl-2-bicyclo[2.2.1]heptanyl) prop-2-enoate) (poly(IBOA)) and its copolymer (poly(IBOA)-co-2-EHA)), prepared by radical polymerization with the addition of a low concentration of crosslinking agent and photoinitiator, was performed. The obtained networks were characterized by FTIR to show the conversion of acrylic band before and after polymerization and by differential scanning calorimetry. The copolymer network has a single glass transition temperature (Tg) that decreases relative to the poly(IBOA). The swelling study of poly(IBOA-co-2-EHA) was carried out by gravimetric method, in a series of polar (methanol, ethanol, propan-1-ol, butan-1-ol, pentan-1-ol, hexan-1-ol and heptan-1-ol) and non-polar (toluene) isotropic solvents. Solubility, interaction and diffusion parameters that influence the swelling of copolymer in the solvents were calculated. The well-established order of swelling (toluene > heptan-1-ol > hexan-1-ol > pentan-1-ol > butan-1-ol > propan-1-ol > ethanol > methanol) in the copolymer was clearly observed, and moreover, the degree of swelling increased with the presence of EHA in the copolymer. A simple diffusion model was applied (Fick's model) to interpret the swelling data. It was found that the nature of solvent shifts the mechanism from diffusion-controlled in the case of alcohols to non-Fickian one for toluene. For a long period, the experimental results were well correlated with the second-order diffusion kinetics of Schott. [ABSTRACT FROM AUTHOR]

Bigels have been mainly applied in the pharmaceutical sector for the controlled release of drugs or therapeutics. However, these systems, with their intricate structures, hold great promise for wider application in food products. Besides their classical role as carrier and target delivery vehicles for molecules of interest, bigels may also be valuable tools for building complex food structures. In the context of reducing or even eliminating undesirable (but often highly functional) food components, current strategies often critically affect food structure and palatability. The production of solid fat systems that are trans-fat-free and have high levels of unsaturated fatty acids is one of the challenges the food industry currently faces. According to recent studies, bigels can be successfully used as ingredients for total or partial solid fat replacement in complex food matrices. This review aims to critically assess current research on bigels in food and pharmaceutical applications, discuss the role of bigel composition and production parameters on the characteristics of bigels and further expand the use of bigels as solid fat replacers and functional food ingredients. The hydrogel:oleogel ratio, selected gelators, inclusion of surfactants and encapsulation of molecules of interest, and process parameters (e.g., temperature, shear rate) during bigel production play a crucial role in the bigel's rheological and textural properties, microstructure, release characteristics, biocompatibility, and stability. Besides exploring the role of these parameters in bigel production, future research directions for bigels in a food context are explored. [ABSTRACT FROM AUTHOR]

Organogels are an important class of gels, and are comparable to hydrogels owing to their properties as liquid‐infused soft materials. Despite the extensive choice of liquid media and compatible networks that can provide a broader range of properties, relatively few studies are reported in this area. This review presents the applicability of organogels concerning their choice of components, unique properties, and applications. Their distinctive features compared to other gels are discussed, including multi‐stimuli responses, affinity to a broad range of substances, thermal and environmental stability, electronic and ionic conductivity, and actuation. The active role of solvents is highlighted in the versatility of organogel properties. To differentiate between organogels and other gels, these are classified as gels filled with different organic liquids, including highly polar organic solvents and binary solvent systems. Most promising applications of organogels as sophisticated multifunctional materials are discussed in light of their unique features. [ABSTRACT FROM AUTHOR]

Using a perfume oil as a liquid phase, we study the gelling performance of a series of cyclic dipeptides as well as the gelled oils' rheological properties and microstructure. After identifying suitable gelators for perfume oil, this work explores the gels' microstructure, elasticity, and syneresis as a function of the chemical nature of the gelator. A correlation is found between the hydrogen-bonding Hansen solubility parameter and the plateau storage modulus of the gelled oils. For a specific non-polar liquid phase, the gels are more elastic when the hydrogen bonding is stronger. By increasing the gel's elasticity, e.g., by using gelators with stronger non-covalent interactions and forming more resilient networks under shear, the tendency for syneresis is decreased. Overall, this work showed that the Hansen parameter approach can be used for the design of organogels and to tune their material properties for specific applications. [ABSTRACT FROM AUTHOR]

Solid lipid nanoparticles (SLNs) are used extensively to achieve site-specific drug delivery with improved bioavailability and reduced toxicity. This work focused on a new approach to provide site-specific stimuli-responsive delivery of SLNs loaded within thermo-sonic nano-organogel (TNO) variants to deliver the model chemotherapeutic agent 5-FU in treating cervical cancer. Pharmaceutically stable nanospherical SLNs comprising poly-L-lactic acid (PLA), palmitic acid (PA), and polyvinyl alcohol (PVA) were prepared and incorporated into TNO variants augmented by external thermal and ultrasound stimuli for release of 5-FU in the cervix. Results revealed that rate-modulated 5-FU release was achieved from SLNs (particle size =450.9 nm; PDI =0.541; zeta potential =−23.2 mV; %DL =33%) within an organogel upon exposure to either a single (thermo-) and/or both (thermo-sonic) stimuli. 5FU was released from all TNO variants with an initial burst on day 1 followed by sustained release over 14 days. TNO 1 provided desirable release over 15 days (44.29% vs. 67.13% under single (T) or combined (TU) stimuli, respectively). Release rates were primarily influenced by the SLN:TO ratio in tandem with biodegradation and hydrodynamic influx. Biodegradation by day 7 revealed that variant TNO 1 (1:5) released 5FU (46.8%) analogous to its initial mass than the other TNO variants (i.e., ratios of 2:5 and 3:5). FT-IR spectra revealed assimilation of the system components and corroborative with the DSC and XRD analysis (i.e., in ratios of PA:PLA 1:1 and 2:1). In conclusion, the TNO variants produced may be used as a potential stimuli-responsive platform for the site-specific delivery of chemotherapeutic agents such as 5-FU to treat cervical cancer. [ABSTRACT FROM AUTHOR]

Supramolecular gels were developed by taking advantage of an assembly of small dipeptides containing pyrrolo-pyrazole scaffolds. The dipeptides were prepared through a robust and ecofriendly synthetic approach from the commercially available starting materials of diazoalkanes and maleimides. By playing with the functionalization of the scaffold, the choice of the natural amino acid, and the stereochemistry, we were able to obtain phase-selective gels. In particular, one peptidomimetic showed gelation ability and thermoreversibility in aromatic solvents at very low concentrations. Rheology tests showed a typical viscoelastic solid profile, indicating the formation of strong gels that were stable under high mechanical deformation. NMR studies were performed, allowing us to determine the conformational and stereochemical features at the base of the supramolecular interactions.

It was first discovered that the excellent gelation ability of tea saponin can be obtained by introducing long-chain alkyl groups of dodecanoyl chloride into the glycosyl portion with direct esterification. The modified dodecanoyl chloride–tea saponin (DC-TS) was successfully synthesized and characterized with NMR, MS, and FT-IR. The tests showed that the long-chain alkyl group was successfully introduced. Combined with SEM and X-ray diffraction patterns, we found that the stable lamellar shape gels of DC-TS were formed in a variety of solvents. More interestingly, organogel was also obtained by adjusting good solvent and poor solvent as mixed solvent. It is worth noting that the driving force of organogels is the combination of hydrogen bonding and the hydrophobic interaction of the introduced alkyl chains with the rigid backbone of pentacyclic triterpenes. The modified tea saponin, a natural green surfactant, was discovered to have gelation properties, which has broadened tea saponin’s scope of application and made it more promising.

[Display omitted] Organic solvents are often used for cleaning highly water-sensitive artifacts in modern/contemporary art. Due to the toxicity of most solvents, confining systems must be formulated to use these fluids in a safe and controlled way. We propose here castor oil (CO) organogels, obtained thorough cost-effective sustainable polyurethane crosslinking. This methodology is complementary to previously demonstrated hydrogels, when conservators opt for organic solvents over aqueous formulations. The gels were characterized via Small-angle Neutron Scattering and rheology before and after swelling in two organic solvents commonly adopted in cleaning paintings. The removal of a photo-aged acrylic-ketonic varnish was evaluated under visible and ultraviolet light, and with FTIR 2D imaging. The new gels are dry systems that can be easily stored and loaded with solvents before use. Their nanoscale organization, viscoelasticity and cleaning action are controlled changing the amount of crosslinking, the polymeric backbone, and the loaded solvents. The fluids are confined in the nanosized polymeric mesh of the gels, which are highly retentive, granting controlled release over delicate paint layers, and transparent, allowing monitoring of the cleaning process. These features, along with their sustainable synthesis, candidate the CO organogels as feasible solutions for cultural heritage preservation, expanding the palette of advanced tools for conservators over traditional thickeners. [ABSTRACT FROM AUTHOR]

Liquid photoresists are abundant in the field of light‐based additive manufacturing (AM). However, printing unsupported directly into a vat of material in emerging volumetric AM technologies―typically a benefit due to fewer geometric constraints and less material waste―can be a limitation when printing low‐viscosity liquid monomers and multimaterial constructs due to part drift or sedimentation. With ethyl cellulose (EC), a thermoplastic soluble in organic liquids, a simple three‐component transparent thermoreversible gel photoresist with melting temperature of ≈64 °C is formulated. The physically crosslinked network of the gel leads to storage moduli in the range of 0.1−10 kPa and maximum yield stress of 2.7 kPa for a 10 wt% EC gel photoresist. Nonzero yield stress enables sedimentation‐free tomographic volumetric patterning in low‐viscosity monomer without additional hardware or modification of apparatus. In addition, objects inserted into the print container can be suspended in the gel material which enables overprinting of multimaterial devices without anchors connecting the object to the printing container. Flexural strength is also improved by 100% compared to the neat monomer for a formulation with 7 wt% EC. [ABSTRACT FROM AUTHOR]

The existence of sol–gel transitions is one of the most manifest properties of molecular gels. These transitions reflect their nature since they correspond to the association or dissociation of low weight molecules through non-covalent interactions to form the network constitutive of the gel. Most described molecular gels undergo only one gel-to-sol transition upon heating, and the reverse sol-to-gel transition upon cooling. It has been long observed that different conditions of formation could lead to gels with different morphologies, and that gels can undergo a transition from gel to crystals. However, more recent publications report molecular gels which exhibit additional transitions, for instance gel-to-gel transitions. This review surveys the molecular gels for which, in addition to sol–gel transitions, transitions of different nature have been reported: gel-to-gel transitions, gel-to-crystal transition, liquid–liquid phase separations, eutectic transformations, and synereses. [ABSTRACT FROM AUTHOR]

Fluorophore is essential to enable the fluorescence and optical switching in most of polymer gels. Herein, a novel concept is proposed to develop a fluorophore‐free organogel that is capable of generation of blue fluorescence at transparent state, while it proceeds with optical switching from blue to purple upon phase transition into non‐transparent state in water. Ammonium persulphate (APS) is utilized to initiate co‐crosslinking of hydrophilic acrylamide (AM) and hydrophobic 2,2,3,4,4,4‐hexafluorobutyl acrylate (HFBA) in dimethyl sulphoxide (DMSO) to give organogel of AM@HFBA at 80 °C. APS decomposes to generate not only radicals, but also ammonium bisulfate (ABS) during heating, in which the elements of ABS produce blue fluorescence (λ = 440 nm), excited by UV light (λ = 365 nm). After the phase transition into non‐transparent state, light‐reflection behavior at the phase‐transitioned surface triggers the optical switching of the organogel from blue to purple under UV light. The optical switching is patternable and reversible, which enables the applications of organogel of AM@HFBA for information encoding/encryption and optical‐switchable soft actuators. This method is universal to achieve fluorescence and optical switching for free radical polymerization‐based gel systems as long as they are initiated by APS in DMSO. [ABSTRACT FROM AUTHOR]

Two series of triphenylene-based dimers both having a central fluoromethylene spacer of four or six carbon atoms and ester or amide linkages were synthesised and their phase behaviour investigated. All the synthesised dimers are room-temperature discotic liquid crystals and exhibit hexagonal columnar mesophases that supercool into a stable anisotropic columnar glass. The length of the fluoromethylene spacer has a minor effect on the phase transition temperatures of these dimers. However, dimers 1a and 2a with a (CF2)4 spacer exhibit approximately 40°C higher clearing points and wider mesomorphic phase ranges compared with their hydrocarbon analogs 1c and 2c with a (CH2)4 spacer respectively. Compared to the corresponding ester-linked dimers 1a-c, three amide-linked dimers 2a-c exhibit 20°C higher clearing points upon cooling. The observation indicates not only that the introduction of the fluoromethylene spacer stabilised the mesophase in these discotic dimers, but also that the two interactions have synergistic effects on columnar packing in this system. Moreover, only amide-linked dimers exhibit good gelation property in a mixture of toluene and petrol ether, with a lower critical gelation concentration of 1.5 wt/vol%, thus indicating that gel formation occurred under the collaboration of hydrogen bonding and intrinsic π interactions in these dimers. [ABSTRACT FROM AUTHOR]

Composition and structure of oleogels significantly influence their digestive behaviour, impacting triacylglycerol breakdown and the bioavailability of incorporated compounds. Texture profile analysis showed that sterol-based oleogels (STOs) exhibited 20 times higher hardness than beeswax-based oleogels (BWOs), which showed stronger cohesion due to elasticity sustained by adhesive forces. Tribological assessments revealed similar initial coefficients of friction (COF) for both oleogels. However, fluctuations were observed in BWOs and a gradual decrease in STOs over time, enhancing lubrication, while BWOs recorded higher adhesion. These findings provide insights into their distinct digestive behaviour, with both oleogels undergoing structural disintegration and STOs displaying a higher lipolysis degree. Non-cytotoxicity was confirmed under Caco-2 cells. β-carotene bioaccessibility was influenced by the oleogels' structural modification and values of 4.0 ± 0.7 % for STOs and 2.6 ± 1.1 % for BWOs were recorded. Results highlight the need to optimize formulations to improve bioactive's bioavailability, emphasizing the role of structured gels in modulating digestion dynamics. • Both oleogels, with or without β-carotene, exhibited non-cytotoxic behaviour. • The lipolysis degree was affected by the nature of the gelator used. • Oleogel type impacted its structural resilience during in vitro digestion tests. [ABSTRACT FROM AUTHOR]

Lauric acid was used to synthesize the low-molecular-weight organogelators (LMOGs), derivatives of two endogenous (L)-alanine, (L)-leucine, and three exogenous (L)-valine, (L)-phenylalanine, and (L)-proline amino acids. The nature of processes responsible for the gel formation both in polar and in apolar solvents of such compounds is still under investigation. Knowing that the organization of surfactant molecules affects the properties of nano scale materials and gels, we decided to elucidate this problem using crystallographic diffraction and energy frameworks analysis. The single crystals of the mentioned compounds were produced successfully from heptane/tBuOMe mixture. The compounds form lamellar self-assemblies in crystals. The energetic landscapes of single crystals of a series of studied amphiphilic gelators have been analyzed to explore the gelling properties. The presented results may be used as model systems to understand which supramolecular interactions observed in the solid state and what energy contributions are desired in the designing of new low-molecular-weight organic gelators. [ABSTRACT FROM AUTHOR]

Three simple bisamide derivatives (G1, G2 and G3) with different structural modifications were synthesized with easy synthetic procedures in order to test their gel behaviour. The outcomes showed that hydrogen bonding was essential in gel formation; for this reason, only G1 provided satisfactory gels. The presence of methoxy groups in G2 and the alkyl chains in G3 hindered the hydrogen bonding between N-H and C=O that occurred G1. In addition, G1 provided thermally and mechanical stable gels, as confirmed with Tsol and rheology experiments. The gels of G1 were also responsive under pH stimuli and were employed as a vehicle for drug crystallization, causing a change in polymorphism in the presence of flufenamic acid and therefore providing the most thermodynamically stable form III compared with metastable form IV obtained from solution crystallization. [ABSTRACT FROM AUTHOR]

Toxic organic solvents are constantly being cast out causing serious issues to the environment. In this work, a polyvinyl alcohol (PVA)‐based organogel has been prepared by modification with a long‐chain fatty acid via condensation method without the use of any cross‐linker. Organogel or the semi‐solid material has been used as a sorbent for solvent absorption from the polluted water surface. The prepared organogel was characterized by Fourier Transform‐Infrared Spectroscopy, Nuclear Magnetic Resonance, Wide‐Angle X‐Ray diffraction, scanning electron microscope, Thermogravimetric Analysis while contact angle measurements were also performed. The gel was used as a sorbent for the absorption of organic solvents. The swelling ratio was examined and exhibited absorption performance of 534% with reusable and retention properties. Experiments were performed to find the maximum absorption capacity at 875.5 (g/g), establishing kinetics of second order reaction. The gel can be extracted by scooping after absorption. Thus, making it an effective and ideal material for the removal of a wide array of organic solvents. [ABSTRACT FROM AUTHOR]

The objective of this study is to investigate the effect of addition of various types of emulsifiers on the morph/ology and thermal and mechanical and properties of organogels. For the preparation of the organogels, γ‐oryzanol and β‐sitosterol mixed at 60:40 w/w ratio were dissolved in decane containing various types of emulsifiers, including Span 80, PGPR, and lecithin, and co‐solvents (butanol and pentanone). The firmness, morphology, and thermal properties of the organogels were studied. SEM micrographs showed branched and twisted strands of the tubular network within the gels prepared in decane. Addition of emulsifiers and co‐solvents increased the polarity of the continuous oil phase and noticeably changed the alignment of the tubules. More linear tubular structures that resemble ribbons with elongated tubules were observed. The firmness of the organogels dropped with addition of emulsifiers and co‐solvents, except for Span‐80, where the firmness is initially increased up to 10% w/w and then decreased. The firmness of the gels prepared with PGPR, lecithin, pentanone, and butanol decreased linearly on increasing the respective emulsifier or co‐solvent concentration between 1% and 20% (w/w). The organogels prepared with Span‐80 were stronger than those prepared with PGPR and lecithin. Moreover, the gels prepared with pentanone were stronger than those prepared with butanol. In addition, the gel‐solution transition temperature of the organogels decreased with increasing emulsifier and co‐solvent concentration. The addition of the emulsifiers seems to interfere with the self‐assembly of the tubular structure and disturb the organization of the hydrophobic tail of oryzanol‐sitosterol in the continuous decane phase. This prevents the formation of a complex branched tubular network resulting in weaker gels. [ABSTRACT FROM AUTHOR]

Particle assembly at liquid-liquid interfaces presents a promising bottom-up strategy for creating supramolecular materials with advanced functionalities. However, the significantly lower interfacial tension observed in immiscible organic phases compared to traditional oil-water systems has hindered the effective adsorption and assembly of particles at oil-oil interfaces. In this work, a versatile and effective strategy is presented that utilizes the assembly and jamming of microgels and polymer ligands at non-aqueous liquid-liquid interfaces to create non-aqueous Pickering emulsions and reconfigurable droplet networks. The resulting microgel-polymer complexes form an asymmetric interfacial bilayer with high surface coverage, which effectively minimizes interfacial energy and improves interfacial elasticity. Through a combination of systematic interfacial measurements and molecular dynamics simulations, the underlying mechanisms governing interfacial self-assembly are elucidated. Notably, the stimuli-responsive nature of the microgel-polymer complexes allows for precise control over the interfacial assembly and disassembly by introducing competitive molecules. Furthermore, it is demonstrated that these non-aqueous Pickering emulsions serve as excellent templates for the fabrication of heterogeneous organogels and microgel-based colloidosomes through both covalent and non-covalent crosslinking strategies. This work underscores the potential of non-aqueous interfaces in advancing materials science and opens new avenues for developing multifunctional materials., (© 2025 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

The author reported molecular organogels using N-alkylhydantoins as new low-molecular-weight gelators for the first time, and thixotropic mixed molecular organogels using a set of N-alkylhydantoin gelators with different alkyl chain lengths. These homologous compounds with different alkyl chains are found to form macroscopic crystals or solution states in polar solvents, but form homogeneous organogels in non-polar solvents, such as n-octane and squalane. Although there is no significant increase in the minimum gelation concentration of the mixed molecular gels using squalane as a solvent, these mixed molecular organogels show improved mechanical properties, especially in their thixotropic behavior, which is not observed in the single N-alkylhydantoin gels. Furthermore, they exhibit reversible thixotropic behavior with quick recovery of the gel state in a minute by quantitatively measuring dynamic viscoelasticity measurements of rheometry of mixed molecular gels. Based on the morphological observations of the xerogels, the self-assembling fibers of the gelators become finer, indicating an increase in the density of the mesh structure inside the gel, which could explain its thixotropic behavior. These thixotropic mixed molecular gels may be applicable to ointment base materials, because they are gelled with squalane oil. [ABSTRACT FROM AUTHOR]

We report on investigations into the rheological properties of organogels prepared from triarylamine trisamide (TATA) and oligo phenylene vinylene (OPVOH) molecules in binary organogel gels and in ternary thermoreversible networks with poly vinyl chloride (PVC). In the case of OPVOH, we show that the modulus of the ternary gel is simply the sum of the modulus of each binary gel, corresponding to the so-called Voigt upper limit. In contrast, TATA/PVC ternary gels generally exceed the Voigt upper limit. In an attempt to account for this unexpected outcome, we hypothesized that a de-solvation process might occur in the PVC fibrils that possibly originates in the propensity of TATA molecules to form molecular compounds with the solvent. Finally, the conducting properties of TATA/solvent organogels and TAT/PVC/solvent reversible networks were measured. It was found that they strongly depend on the solvent type but are not significantly altered when PVC is present. Therefore, PVC gels can be made conducive by incorporating TATA fibers. [ABSTRACT FROM AUTHOR]

The article is an overview of the latest achievements in the study of low molecular weight gelling agents based on steroids - cholesterol, estradiol, dehydroepi-androsterone and pentacyclic triterpenoids - arjunolic, glycyrrhetinic acids. These compounds are used as components of smart gels and are of interest for supramolecular chemistry. A gelling agent is a substance that is able to bind various solvents at low concentrations, and the resulting gel has a solid structure which rheological properties are similar to those of solids. Non-covalent interactions: dipole-dipole, van der Waals, electrostatic, hydrogen bonds and π-stacking, are considered as the driving forces for the formation a fibrous network by low molecular weight gelator. In contrast to decades of research into the gelation of polymers, proteins and inorganic substances, low molecular weight organic gelling agents have only recently begun to be actively studied. Their chemical structure is derived from urea, amino acids, carbohydrates, cholesterol and bile acids. Unlike steroid-based gels, information on the use of pentacyclic triterpenoids for the development of low molecular weight gelling agents is extremely limited. The interest in such systems is due to the fact that, like steroids, they have a developed, rigidly organized nanosized molecular platform, making them capable of self-association in polar and nonpolar organic solvents. In addition, the presence of molecules of these compounds in several functional groups that are easily chemically modified, low toxicity and biocompatibility allows them to be considered as promising starting materials for the pharmaceutical industry, in particular for the development of mild dosage forms.

Bigels have been mainly applied in the pharmaceutical sector for the controlled release of drugs or therapeutics. However, these systems, with their intricate structures, hold great promise for wider application in food products. Besides their classical role as carrier and target delivery vehicles for molecules of interest, bigels may also be valuable tools for building complex food structures. In the context of reducing or even eliminating undesirable (but often highly functional) food components, current strategies often critically affect food structure and palatability. The production of solid fat systems that are trans-fat-free and have high levels of unsaturated fatty acids is one of the challenges the food industry currently faces. According to recent studies, bigels can be successfully used as ingredients for total or partial solid fat replacement in complex food matrices. This review aims to critically assess current research on bigels in food and pharmaceutical applications, discuss the role of bigel composition and production parameters on the characteristics of bigels and further expand the use of bigels as solid fat replacers and functional food ingredients. The hydrogel:oleogel ratio, selected gelators, inclusion of surfactants and encapsulation of molecules of interest, and process parameters (e.g., temperature, shear rate) during bigel production play a crucial role in the bigel’s rheological and textural properties, microstructure, release characteristics, biocompatibility, and stability. Besides exploring the role of these parameters in bigel production, future research directions for bigels in a food context are explored.

Despite hundreds of studies involving slide-ring gels derived from cyclodextrin (CD)-based polyrotaxanes (PRs), their covalent cross-linking kinetics are not well characterized. We employ chemorheology as a tool to measure the gelation kinetics of a model slide-ring organogel derived from α-cyclodextrin/poly (ethylene glycol) PRs cross-linked with hexamethylenediisocyanate (HMDI) in DMSO. The viscoelastic properties of the gels were monitored in situ by small-amplitude oscillatory shear (SAOS) rheology, enabling us to estimate the activation barrier and rate law for cross-linking while mapping experimental parameters to kinetics and mechanical properties. Gelation time, gel point, and final gel elasticity depend on cross-linker concentration, but polyrotaxane concentration only affects gelation time and elasticity (not gel point), while temperature only affects gelation time and gel point (not final elasticity). These measurements facilitate the rational design of slide-ring networks by simple parameter selection (temperature, cross-linker concentration, PR concentration, reaction time).