Aqueous Colloidal Suspensions Research Articles

Green Synthesis and Characterization of Antimicrobial Synergistic AgCl/BAC Nanocolloids.

All over the world, one of the major challenges is the green synthesis of potential materials against antimicrobial resistance and viruses. This study demonstrates a simple method like chemistry lab titration to synthesize green, facile, scalable, reproducible, and stable synergistic silver chloride/benzyldimethylhexadecyl-ammonium chloride (AgCl/BAC) colloidal Nanoantimicrobials (NAMs). Nanocolloidal dispersions of AgCl in an aqueous medium are prepared by using silver nitrate (AgNO3) as precursor and BAC as both sources of chloride and stabilizer, holding an asymmetric molecular structure. The synthetic approach is scalable and green. Both the morphology and stability of AgCl/BAC nanocolloids (NCs) were investigated as a function of different molar fractions of the reagents. AgCl/BAC NCs were characterized by transmission electron microscopy (TEM) and X-ray photoelectron and UV–vis spectroscopies. Zeta potential measurements revealed increasing positive potential values at every stage of the synthesis. Size distribution and hydrodynamic diameter of the particles were measured by dynamic light scattering (DLS), which predicted the formation of BAC layered structures associated with the AgCl nanoparticles (NPs). Small-angle X-ray scattering (SAXS) experiments verify the thickness of the BAC bilayer around AgCl. The produced AgCl/BAC NCs probably have synergistic antimicrobial properties from the AgCl core and the biocide BAC shell. AgCl/BAC NCs stability over months was investigated. The experimental evidence supports the morphological stability of the AgCl/BAC NCs, while higher positive zeta potential values anticipate a long-term antimicrobial effect: a higher surface charge causes NPs to be potentially more lethal to bacteria. AgCl/BAC antimicrobial aqueous colloidal suspensions will be used as additives for the industrial production of antimicrobial coatings.

Criteria for Crack Formation and Air Invasion in Drying Colloidal Suspensions.

The drying of sessile drops of aqueous colloidal suspensions leads to the formation of a close-packed particle deposit. As water evaporates, a solidification front propagates from the edge of the drop toward the center, leaving behind a thin disk-shaped deposit. For drops with sufficiently large particle volume fractions, the deposit eventually covers the entire wetted area. In this regime, the dynamics of the deposit growth is governed by volume conservation across a large range of particle volume fractions and drying times. During drying, water flows radially through the deposit to compensate for evaporation over the solid's surface, creating a negative pore pressure in the deposit which we rationalize with a hydrodynamic model. We show that the pressure inside the deposit controls both the onset of crack formation and the onset of air invasion. Two distinct regimes of air invasion occur, which we can account for using the same model that further provides a quantitative criterion for the crossover between the two regimes.

Antiseptic Materials on the Base of Polymer Interpenetrating Networks Microgels and Benzalkonium Chloride.

Polymer microgels, including those based on interpenetrating networks (IPNs), are currently vastly studied, and their practical applications are a matter of thriving research. In this work, we show the perspective for the use of polyelectrolyte IPN microgels either as scavengers or carriers of antiseptic substances. Here, we report that poly-N-isopropylacrylamide/polyacrylic acid IPN microgels can efficiently absorb the common bactericidal and virucidal compound benzalkonium chloride. The particles can form a stable aqueous colloidal suspension or be used as building blocks for soft free-standing films. Both materials showed antiseptic efficacy on the examples of Bacillus subtilis and S. aureus, which was approximately equal to the commercial antibiotic. Such polymer biocides can be used as liquid disinfectants, stable surface coatings, or parts of biomedical devices and can enhance the versatility of the possible practical applications of polymer microgels.

Hollow Filaments Synthesized by Dry-Jet Wet Spinning of Cellulose Nanofibrils: Structural Properties and Thermoregulation with Phase-Change Infills.

We use dry-jet wet spinning in a coaxial configuration by extruding an aqueous colloidal suspension of oxidized nanocellulose (hydrogel shell) combined with airflow in the core. The coagulation of the hydrogel in a water bath results in hollow filaments (HF) that are drawn continuously at relatively high rates. Small-angle and wide-angle X-ray scattering (SAXS/WAXS) reveals the orientation and order of the cellulose sheath, depending on the applied shear flow and drying method (free-drying and drying under tension). The obtained dry HF show Young’s modulus and tensile strength of up to 9 GPa and 66 MPa, respectively. Two types of phase-change materials (PCM), polyethylene glycol (PEG) and paraffin (PA), are used as infills to enable filaments for energy regulation. An increased strain (9%) is observed in the PCM-filled filaments (HF-PEG and HF-PA). The filaments display similar thermal behavior (dynamic scanning calorimetry) compared to the neat infill, PEG, or paraffin, reaching a maximum latent heat capacity of 170 J·g–1 (48–55 °C) and 169 J·g–1 (52–54 °C), respectively. Overall, this study demonstrates the facile and scalable production of two-component core-shell filaments that combine structural integrity, heat storage, and thermoregulation properties.

Influence of Acetaminophen on Molecular Adsorption and Transport Properties at Colloidal Liposome Surfaces Studied by Second Harmonic Generation Spectroscopy.

Time-resolved second harmonic generation (SHG) spectroscopy is used to investigate acetaminophen (APAP)-induced changes in the adsorption and transport properties of malachite green isothiocyanate (MGITC) dye to the surface of unilamellar 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) liposomes in an aqueous colloidal suspension. The adsorption of MGITC to DOPC liposome nanoparticles in water is driven by electrostatic and dipole–dipole interactions between the positively charged MGITC molecules and the zwitterionic phospholipid membranes. The SHG intensity increases as the added MGITC dye concentration is increased, reaching a maximum as the MGITC adsorbate at the DOPC bilayer interface approaches a saturation value. The experimental adsorption isotherms are fit using the modified Langmuir model to obtain the adsorption free energies, adsorption equilibrium constants, and the adsorbate site densities to the DOPC liposomes both with and without APAP. The addition of APAP is shown to increase MGITC adsorption to the liposome interface, resulting in a larger adsorption equilibrium constant and a higher adsorption site density. The MGITC transport times are also measured, showing that APAP decreases the transport rate across the DOPC liposome bilayer, especially at higher MGITC concentrations. Studying molecular interactions at the colloidal liposome interface using SHG spectroscopy provides a detailed foundation for developing potential liposome-based drug-delivery systems.

Evaluation of synthesized polyaniline nanofibres as corrosion protection film coating on copper substrate by electrophoretic deposition

In this current paper, we report the use of inexpensive, simple electrophoretic deposition (EPD) technique in developing polyaniline (PANI) aqueous colloidal suspension coating on copper (Cu) substrate. Polyaniline nanoparticle films were deposited electrophoretically on the surface of copper sheet electrode. A colloidal suspension with high stability was produced by a liquid polyaniline in the presence of formic acid and acetonitrile as electrolyte for the EPD process. The suspension of the PANI was characterized by measuring the zeta potential of the suspension using zeta-sizer analyser. The PANI coating was used as barrier for corrosion protection of the Cu sheet. Operating parameters such as operating time, applied voltage, and the concentration were used with deposition at the cathode. Characterization such as XRD, SEM, FT-IR, and UV–Vis was carried out, and the corrosion protection offered by the PANI on the Cu surface was examined using potentiodynamic (Tafel) polarization in 3.5% NaCl solution at room temperature. As a result, the optimum parameters for obtaining a homogenous coating on the Cu sheet were attained at the voltage of 15 V and deposition time of 180 s with 50 mg/mL PANI concentration. The attained results indicated inhibition efficiency for PANI deposit of 92.92% indicating protection against corrosion.

Atomic luminescence of Ag during single-bubble sonolysis of silver nanoparticles aqueous suspension

For the first time, luminescence of Ag atoms was recorded during moving single-bubble sonolysis of silver nanoparticles aqueous colloidal suspension. This glow is caused by the entry of nanoparticles into a bubble deformable during motion and their decomposition to atoms with collisional excitation in the nonequilibrium plasma of the bubble. Nanoparticles were obtained by multibubble sonolysis of an AgNO3 solution with the addition of honey. This method was used to synthesize a stable suspension of Ag nanoparticles with an average size of ~ 10 nm. By comparing the experimental spectrum of this suspension and simulated spectra of Ag, the electron temperature in the bubble plasma was found to be ~ 10 000 K. Keywords: single-bubble sonoluminescence, silver nanoparticles, electron plasma temperature.

Structure and Self-Assembly of Lytic Polysaccharide Monooxygenase-Oxidized Cellulose Nanocrystals

Cellulose-derived nanomaterial building blocks, including cellulose nanocrystals (CNCs), have become increasingly important in sustainable materials development. However, the preparation of CNCs requires hazardous chemicals to introduce surface charges that enable liquid crystalline phase behavior, a key parameter for obtaining self-organized, nanostructured materials from CNCs. Lytic polysaccharide monooxygenases (LPMOs), oxidative enzymes that introduce charged carboxyl groups on their cleavage sites in aqueous reaction conditions, offer an environmentally friendly alternative. In this work, two C1-oxidizing LPMOs from fungus Neurospora crassa, one of which contained a carbohydrate-binding module (CBM), were investigated for CNC preparation. The LPMO-oxidized CNCs shared similar features with chemical-derived CNCs, including colloidal stability and a needle-like morphology with typical dimensions of 7 ± 3 nm in width and 142 ± 57 nm in length for CBM-lacking LPMO-oxidized CNCs. The self-organization of the LPMO-oxidized CNCs was characterized in suspensions and solution cast films. Both LPMO-oxidized CNCs showed electrostatically driven self-organization in aqueous colloidal suspension and pseudo-chiral nematic ordering in solid films. The CBM-lacking LPMO generated a higher carboxyl content (0.70 mmol g–1), leading to a more uniform CNC self-organization, favoring LPMOs without CBMs for CNC production. The obtained results demonstrate production of stable colloidal CNCs with self-assembly by C1-oxidizing LPMOs toward a completely green production of advanced, nanostructured cellulose materials.

Filtration of Nanoparticle Agglomerates in Aqueous Colloidal Suspensions Exposed to an External Radio-Frequency Magnetic Field.

The study investigated the phenomenon of the fast aggregation of single-domain magnetic iron oxide nanoparticles in stable aqueous colloidal suspensions due to the presence of a radio-frequency (RF) magnetic field. Single-domain nanoparticles have specific magnetic properties, especially the unique property of absorbing the energy of such a field and releasing it in the form of heat. The localized heating causes the colloid to become unstable, leading to faster agglomeration of nanoparticles and, consequently, to rapid sedimentation. It has been shown that the destabilization of a stable magnetic nanoparticle colloid by the RF magnetic field can be used for the controlled filtration of larger agglomerates of the colloid solution. Two particular cases of stable colloidal suspensions were considered: a suspension of the bare nanoparticles in an alkaline solution and the silica-stabilized nanoparticles in a neutral solution. The obtained results are important primarily for biomedical applications and wastewater treatment.

Cryoplasma-mediated fabrication of Au-TiO2 composite film using freezing ice front templated structures

Ice-templating is a powerful technique that exploits self-organized ice structures formed during the freezing of colloidal suspensions as templates to fabricate microstructured materials. However, the active introduction of reactivity to the ice-templating process remains limited. In this study, a Au-TiO2 composite film composed of gold and titanium oxide (TiO2) was fabricated on a frozen aqueous colloidal suspension, using cryoplasma to introduce reactive species to the frozen suspension. Auric ions and TiO2 nanoparticles were segregated on the ice body by one-directional freezing of the aqueous colloidal suspension from the lower side. Meanwhile, a cryoplasma, in which the gas temperature was controlled to be lower than the melting point of water, was irradiated onto the frozen aqueous colloidal suspension to facilitate the chemical reduction of gold ions and the formation of gold bridges between TiO2 nanoparticles. The face of the fabricated Au-TiO2 composite film that had been adjacent to the ice structure during its formation was shown to possess both greater roughness and higher photocatalytic activity for methylene blue degradation when the aqueous colloidal suspension was frozen at a higher temperature during the fabrication of the composite film. The temperature dependence of the roughness and photocatalytic activity indicates a potential of the combination of cryoplasma irradiation and ice-templating processes for structure-controlled fabrication of composite film materials, suggesting that alterations in the structure of the freezing ice front that occur with changes in temperature can be harnessed.

Co-Encapsulation of Methylene Blue and PARP-Inhibitor into Poly(Lactic-Co-Glycolic Acid) Nanoparticles for Enhanced PDT of Cancer.

The development of resistance against photodamage triggered by photodynamic therapy (PDT) is ascribed mainly to the cellular redox defenses and repair. If the tumor tissue is not promptly eliminated by the first few PDT sessions, PDT-resistance can be favored, challenging the efficacy of the treatment. Although the mechanism of PDT resistance is still unclear, in vitro assays have evidenced that it can be developed through the PARP damage-repair signaling pathway. Therefore, inhibition of poly(adenosine diphosphate (ADP)-ribose) polymerase (PARP) has the potential to increase PDT efficacy. This work reports on the synthesis of a controlled release system of a photosensitizer, methylene blue (MB) and a PARP-inhibitor, the veliparib. MB and veliparib were co-encapsulated in poly(lactic-co-glycolic acid) (PLGA) nanoparticles (VMB-NPs). A colloidal stable aqueous suspension of nanoparticles was obtained. The average hydrodynamic diameter was 90 nm and a narrow size distribution was obtained, with a polydispersity index (PDI) of 0.08. The release kinetics of MB and veliparib from VMB-NPs showed an initial burst of 8.7% and 58.3% release of the total amounts of MB and veliparib respectively, in the first 6 h, and a delayed release of up to 11.3% and 70%, in 19 days, for MB and veliparib, respectively. The VMB-NPs showed no cytotoxicity in the dark but the viability of B16F10-Nex2 cells decreased by 36% when the cells were irradiated (102 J/cm2, 660 nm) and treated with VMB-NPs containing 1.0 µM of MB and 8.3 µM of veliparib. Considering the increased photoactivity even at low MB and veliparib concentrations and the absence of cytotoxicity in dark, the co-encapsulation of MB and veliparib was shown to be a promising strategy to improve the PDT efficacy.

Electro-optical properties of a liquid crystalline colloidal solution of rod shaped V2O5 nanoparticles and carbon nanotubes in an alternating current electric field

ABSTRACT We study the liquid crystalline phase behaviour of the two-component aqueous colloidal suspensions of multiwalled carbon nanotubes (MWCNTs) and rod-like vanadium pentoxide (V2O5) nanoparticles. The phase diagram features a stable nematic phase in a wide range of concentration of solid components. The oriented nematic phase of the two-component suspension was exposed to the action of alternating current electric field. A variation in MWCNTs concentration within 0.01–0.51 wt.% demonstrates a significant increase in the optical response of the system to the applied electric field.

Opal-based terahertz optical elements fabricated by self-assembly of porous SiO2 nanoparticles.

In this paper, we study artificial opals as a promising material platform for terahertz (THz) optics. Materials were synthesized using self-assembly of porous SiO2 nanoparticles and annealing at different temperatures to further tune their optical properties. Two distinct approaches for the fabrication of bulk THz optics from these novel materials were considered. First, THz cylindrical lenses of identical geometry but different refractive indices and focal lengths were produced using standard mechanical processing of opals, in order to highlight their compatibility with conventional technologies of bulk optics fabrication. Second, a THz axicone was made via direct sedimentation of aqueous colloidal suspension of SiO2 nanoparticles in the mold of geometry inverse to that of a desired optical shape, followed by annealing and polishing. The second approach has an advantage of being considerably less labor intensive, while capable of obtaining optical elements of complex geometries. Thus fabricated bulk THz optical elements were studied experimentally using continuous-wave THz imaging, and the results were compared with 2D and 3D numerical predictions based on the finite-difference time-domain and finite-element frequency-domain methods. Our findings highlight technological robustness of the developed THz optical material platform and, thus, open the door for creating a variety of bulk THz optical elements of complex shapes and widely-tunable optical performance.

Hetero-network hydrogels crosslinked with silica nanoparticles for strategic control of thermal responsive property.

Two thermoresponsive copolymers with different lower critical solution temperatures (LCSTs) were crosslinked using silica nanoparticles to afford hybrid hydrogels exhibiting two distinct thermo-responsivities. The thermo-responsive copolymers were synthesised by free radical polymerisation from a monomer with a reactive side chain (3-methacryloxypropyl trimethoxysilane (S)) and water-soluble monomers with different thermo-responsivities (N-isopropyl acrylamide (N) or N-(3-methoxy propyl)acrylamide (M)). The obtained reactive copolymers, poly(N-isopropyl acrylamide-co-3-methacryloxypropyl trimethoxysilane) (pNS) and poly(N-(3-methoxy propyl acrylamide-co-3-methacryloxypropyl trimethoxysilane)) (pMS), were characterized by multiple techniques including 1H NMR and FTIR spectroscopy. The hetero-network hybrid hydrogels were easily prepared by mixing aqueous solutions of the copolymer with an aqueous colloidal silica suspension; their gelation properties could be tuned by varying the amounts of pNS, pMS, and Si. Differential scanning calorimetric analysis showed that the hetero-network hydrogel exhibited a critical two-step phase transition at temperatures around the LCST of each copolymer (33 °C for pNS, 73 °C for pMS), indicating that each polymer does not disturb the phase transitions of the other. The deswelling of the hetero-network hydrogel could be controlled with respect to temperature and time.

Folic acid conjugation of magnetite nanoparticles using pulsed electrohydraulic discharges

The sonochemical coprecipitation reaction with moderate ultrasound irradiation in a low vacuum environment was used to obtain aqueous colloidal suspensions of iron oxide nanoparticles (IONPs). The synthesized magnetite nanoparticles were conjugated directly by folic acid using electrohydraulic discharges as a processing technique before modification of the surface of the nanoparticles. Electrohydraulic discharges were applied in two operational modes with high and low power pulsed direct currents between the electrodes. The physical and chemical properties of the obtained samples were studied using X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS) and small angle X-ray scattering (SAXS). The investigation proved an inverse cubic spinel structure of magnetite with folic acid attachment to the magnetite surface (mean crystallite diameter in the samples, D, ranges 25?31 nm by XRD and SAXS). It was found that the processing with electrohydraulic discharges increased the colloidal stability of the folic acid-magnetite nanoparticle dispersions.

Атомарная люминесценция Ag при однопузырьковом сонолизе водной суспензии наночастиц серебра

For the first time, luminescence of Ag atoms was recorded during moving single-bubble sonolysis of silver nanoparticles aqueous colloidal suspension. This glow is caused by the entry of nanoparticles into a bubble deformable during motion and their decomposition to atoms with collisional excitation in the nonequilibrium plasma of the bubble. Nanoparticles were obtained by multibubble sonolysis of an AgNO3 solution with the addition of honey. This method was used to synthesize a stable suspension of Ag nanoparticles with an average size of ~ 10 nm. By comparing the experimental spectrum of this suspension and simulated spectra of Ag, the electron temperature in the bubble plasma was found to be ~ 10000 K.

Detection of the TiO2 Concentration in the Protective Coatings for the Cultural Heritage by Means of Hyperspectral Data

Nanotechnology-based materials are currently being tested in the protection of cultural heritage: ethyl silicate or silica nanoparticles dispersed in aqueous colloidal suspensions mixed with titanium dioxide are used as a coating for stone materials. These coatings can play a key role against the degradation of stone materials, due to the deposit of organic matter and other contaminants on the substrate, a phenomenon that produces a greater risk for the monuments in urban areas because of the increasing atmospheric pollution. However, during the application phase, it is important to evaluate the amount of titanium dioxide in the coatings on the substrate, as it can produce a coverage effect on the asset. In this work, we present the hyperspectral data obtained through a field spectroradiometer on samples of different stone materials, which have been prepared in laboratory with an increasing weight percentage of titanium dioxide from 0 to 8 wt%. The data showed spectral signatures dependent on the content of titanium dioxide in the wavelength range 350–400 nm. Afterwards, blind tests were performed on other samples in order to evaluate the reliability of these measurements in detecting the unknown weight percentage of titanium dioxide. Moreover, an investigation was also performed on a test application of nanoparticle coatings on a stone statue located in a coastal town in Calabria (southern Italy). The results showed that the surveys can be useful for verifying the phase of application of the coating on cultural heritage structures; however, they could also be used to check the state of the coated stone directly exposed over time to atmospheric, biological and chemical agents.

Hand-ground fullerene-nanodiamond composite for photosensitized water treatment and photodynamic cancer therapy

The unique capability of fullerene (C60) to absorb light and generate reactive oxygen species (ROS) has been extensively studied for photosensitized water treatment and cancer therapy. Various material synthesis strategies have been proposed in parallel to overcome its intrinsic hydrophobicity and to enhance availability in water and physiological media. We present here a strikingly simple approach to make C60 available to these applications by hand-grinding dry C60 powder with nanodiamond (ND) using a mortar and pestle. The resulting ND-C60 composite was found to form a stable aqueous colloidal suspension and efficiently drive photosensitized production of ROS under visible light illumination. ND-C60 rapidly adsorbed and oxidized organic contaminants by photogenerated ROS. In the experiments for photodynamic cancer therapy, ND-C60 was internalized by cancer cells and induced cell apoptosis without noticeable toxicity. Treatment of tumor-bearing mice with ND-C60 and light irradiation resulted in tumor shrinkage and prolonged survival time.

Influence of PLGA nanoparticles on the deposition of model water-soluble biocompatible polymers by dip coating

This work relies on the use of dip-coating at various withdrawal speeds to form nanocomposite films, with a detailed analysis of the influence of the mode of deposition on the nanoparticle (NP) concentration in the dried film. While the deposition of polymer solutions on the one hand and colloidal suspensions of NPs on the other hand have been separately studied by dip coating, their combination is far being a simple superposition of the two separate behaviors. The formation of nanocomposite thin films composed of model water-soluble biocompatible polymers (polyvinyl alcohol - PVA and polyvinylpyrrolidone - PVP) loaded with poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) was studied through a dip coating process. Flat silicon substrates were removed at a controlled withdrawal speed from an aqueous colloidal suspension. Thin films of PLGA NPs with concentrations ranging from 1 to 10 % wt./wt. in PVA or PVP matrices were prepared. The presence of nanoparticles on the well-established process of thin film deposition was examined, as well as the influence of the deposition regime on the nanoparticle concentration in the deposited coating. We demonstrate that the presence of colloidal dispersion of PLGA nanoparticles in water solution of PVA and PVP does not modify the process of film deposition by dip coating. A typical “V” shaped curve was observed, with two well-known deposition regimes: capillary and draining modes respectively obtained at low and high withdrawal speeds. Due to crystallization at low withdrawal speed (favored by slow evaporation of the solvent) it was not possible to identify individual PLGA nanoparticles by AFM in the case of the PVA matrice. Amorphous PVP nanocomposite films were successfully prepared by dip coating, and allowed us to identify individual PLGA nanoparticles with AFM. Because of the prevalence of an evaporation-driven phenomenon at low withdrawal speed, incorporation of NPs was observed over the whole range of withdrawal speeds, showing original behavior compared to recent studies relying on a pure Landau-Levich regime (i.e. non-evaporative systems). Our results indicate that the nanoparticles were not equally retrieved from the solution in the capillary and the draining regimes. This suggests that the balance between the viscous drag and the interfacial effects depends on the deposition mode and calls for a more detailed analysis of the physical processes involved in both regimes.

New water-based fluorescent nanofluid containing 2D titanium carbide MXene sheets: a comparative study of its thermophysical, electrical and optical properties with amine and carboxyl covalently functionalized graphene nanoplatelets

The aqueous colloidal suspension of two-dimensional (2D) sp2 carbon and carbide materials has promising thermal and electrical properties to be used as a coolant for heat transfer applications. However, the application of graphene nanoplatelets (GNPs) nanofluids is extensively limited by its insufficient dispersibility and stability in the base fluid of water. Therefore, surface modification and post-functionalization of GNPs should be considered as further treatments to enhance their nanofluid properties, which is not economical for large-scale production. In the current study, we presented the processing, thermophysical, electrical and optical properties of a new generation of carbon-based nanofluid containing highly exfoliated autofluorescent hydrophilic 2D titanium carbide MXene (Ti3C2Tx) nanosheets. For the first time, the microstructure and nanofluid properties of the water-based Ti3C2Tx at two concentrations of 0.1 and 0.2 mass% have been further compared with covalently and non-covalently functionalized GNPs. Our results showed that the thermal/electrical conductivities of 0.1 and 0.2% MXene are remarkably higher (0.732 and 0.828 W m─1 K─1, 1213 and 2690 µS cm─1, respectively) compared with non-covalent GNPs at same concentrations (0.679 and 0.702 W m─1 K─1, 723 and 1425 µS cm─1, respectively) and competitive with COOH- and NH2-mediated GNPs samples. Additionally, the prominent stability and autofluorescence properties of MXene composite are other advantages supporting its nanofluid applications. The fluorescent MXene nanofluid at the different excitation/emission wavelengths (377–586 nm/447–647 nm) conferred a suitable optical contrast for visualization. Taken together, Ti3C2Tx material might open up a robust gateway for the application of carbon-based nanofluids in advanced heat transfer systems.