Nanodiamond Research Articles

Enhancement of dual zero phonon line emissions in nanodiamonds using quasiperiodic photonic structures.

Color centers in nanodiamonds (NDs) have been largely explored by coupling to a photonic structured matrix (PSM) to amplify visible range emission features, enhancing their use in quantum technologies. Here, we study the emission enhancement of dual near-infrared zero phonon line (ZPL) emission from silicon-boron (SiB) and silicon-vacancy (SiV-) centers in NDs using a spontaneously emerged low index-contrast quasiperiodic PSM, having micron-scale air pores. An intensity enhancement factor of 6.15 for SiV- and 7.8 for SiB ZPLs is attained for the PSM sample compared to a control sample. We find Purcell enhancement of 2.77 times for the PSM sample using spatial-dependent decay rate measurements, supported by localized field intensity confinement in the sample. Such cavity-like emission enhancement and lifetime reduction are enabled by an in-plane order-disorder scattering in the PSM sample substantiated by pump-dependent emission measurements. The results put forward a facile approach to tailor the near-infrared dual ZPL emission from NDs using nanophotonic structures.

Exploring nanodiamonds: leveraging their dual capacities for anticancer photothermal therapy and temperature sensing.

Cancer has become a primary global health concern, which has prompted increased attention towards targeted therapeutic approaches like photothermal therapy (PTT). The unique optical and magnetic properties of nanodiamonds (NDs) have made them versatile nanomaterials with promising applications in biomedicine. This comprehensive review focuses on the potential of NDs as a multifaceted platform for anticancer therapy, mainly focusing on their dual functionality in PTT and temperature sensing. The review highlighted NDs' ability to enhance PTT through hybridization or modification, underscoring their adaptability in delivering small molecule reagents effectively. Furthermore, NDs, particularly fluorescent nanodiamonds (FNDs) with negatively charged nitrogen-vacancy centers, enable precise temperature monitoring, enhancing PTT efficacy in anticancer treatment. Integrating FNDs into PTT holds promise for advancing therapeutic efficacy by providing valuable insights into localized temperature variations and cell death mechanisms. This review highlights new insights into cancer treatment strategies, showcasing the potential of NDs to revolutionize targeted therapeutics and improve patient outcomes.

Designing functionalized nanodiamonds with hyaluronic acid-phospholipid conjugates for enhanced cancer cell targeting and fluorescence imaging capabilities.

Nanomedicine aims to develop smart approaches for treating cancer and other diseases to improve patient survival and quality of life. Novel nanoparticles as nanodiamonds (NDs) represent promising candidates to overcome current limitations. In this study, NDs were functionalized with a 200 kDa hyaluronic acid-phospholipid conjugate (HA/DMPE), enhancing the stability of the nanoparticles in water-based solutions and selectivity for cancer cells overexpressing specific HA cluster determinant 44 (CD44) receptors. These nanoparticles were characterized by diffuse reflectance Fourier-transform infrared spectroscopy, Raman spectroscopy, and photoluminescence spectroscopy, confirming the efficacy of the functionalization process. Scanning electron microscopy was employed to evaluate the size distribution of the dry particles, while dynamic light scattering and zeta potential measurements were utilized to evaluate ND behavior in a water-based medium. Furthermore, the ND biocompatibility and uptake mediated by CD44 receptors in three different models of human adenocarcinoma cells were assessed by performing cytofluorimetric assay and confocal microscopy. HA-functionalized nanodiamonds demonstrated the advantage of active targeting in the presence of cancer cells expressing CD44 on the surface, suggesting higher drug delivery to tumors over non-tumor tissues. Even CD44-poorly expressing cancers could be targeted by the NDs, thanks to their good passive diffusion within cancer cells.

Cellular uptake and fate of cationic polymer-coated nanodiamonds delivering siRNA: a mechanistic study.

Gene silencing using small interfering RNAs (siRNAs) is a selective and promising approach for treatment of numerous diseases. However, broad applications of siRNAs are compromised by their low stability in a biological environment and limited ability to penetrate cells. Nanodiamonds (NDs) coated with cationic polymers can enable cellular delivery of siRNAs. Recently, we developed a new type of ND coating based on a random copolymer consisting of (2-dimethylaminoethyl) methacrylate (DMAEMA) and N-(2-hydroxypropyl) methacrylamide (HPMA) monomers. These hybrid ND-polymer particles (Cop+-FND) provide near-infrared fluorescence, form stable complexes with siRNA in serum, show low toxicity, and effectively deliver siRNA into cells in vitro and in vivo. Here, we present data on the mechanism of cellular uptake and cell trafficking of Cop+-FND : siRNA complexes and their ability to selectively suppress mRNA levels, as well as their cytotoxicity, viability and colloidal stability. We identified clathrin-mediated endocytosis as the predominant entry mechanism for Cop+-FND : siRNA into U-2 OS human bone osteosarcoma cells, with a substantial fraction of Cop+-FND : siRNA following the lysosome pathway. Cop+-FND : siRNA potently inhibited the target GAPDH gene with negligible toxicity and sufficient colloidal stability. Based on our results, we suggest that Cop+-FND : siRNA can serve as a suitable in vivo delivery system for siRNA.

Phonon thermophoresis of crystalline nanoparticles in liquids.

Our nonequilibrium thermodynamic model of thermodiffusion in molecular liquid systems is used to examine the role of thermal phonons in the thermophoresis of liquid suspensions of crystalline nanoparticles, which tend to have high thermal conductivity. The Soret coefficient used to characterize stationary thermodiffusion is related to differences in entropy between a particle and the body of liquid that it displaces. Calculated phonon Soret coefficients for graphite and diamond nanoparticles in three polar solvents are used to establish parameters where the phonon mechanism is expected to dominate particle thermophoresis compared to slip-flow caused by forces induced in the surface layer by the temperature gradient. Because the active mode of thermal conductivity in crystals varies with particle size, phonon thermophoresis is expected to dominate within a specific range of particle size, which varies with the properties of the particle and suspending liquid. For graphite and diamond particles in polar solvents the model estimates a size range of around 10-100 nm. Finally, thermophoretic particle accumulation is ultimately limited by the increasing concentration of particles having high thermal conductivity because the zone of particle concentration decreases the local temperature gradient that drives thermophoresis. The respective nonperturbing concentration is evaluated as the function of the size of a given material.

Interaction of supported phospholipid bilayers with diamond nanoparticles non-covalently functionalized with a cationic polyelectrolyte

Cationic polymer-wrapped diamond nanoparticles interact with lipid bilayers to reveal the influence of phospholipid composition and surface charge on nanoparticle-membrane interactions.

Enhancing the sequence coverage of nanodiamond-extracted early secretory proteins from the Mycobacterium tuberculosis complex.

The unambiguous identification of protein species requires high sequence coverage. In this study, we successfully improved the sequence coverage of early secretory 10 kDa cell filtrate protein (CFP-10) and 6 kDa early secretory antigenic target (ESAT-6) proteins from the Mycobacterium tuberculosis complex (MTC) in broth culture media with the use of the 4-chloro-α-cyanocinnamic acid (Cl-CCA) matrix. Conventional matrices, α-cyano-hydroxy-cinnamic acid (CHCA) and 2,5-dihydroxybenzoic acid (DHB), were also used for comparison. After nanodiamond (ND) extraction, the sequence coverage of the CFP-10 protein was 87% when CHCA and DHB matrices were used, and the ESAT-6 protein was not detected. On the other hand, the sequence coverage for ND-extracted CFP-10 and ESAT-6 could reach 94% and 100%, respectively, when the Cl-CCA matrix was used and with the removal of interference from bovine serum albumin (BSA) protein and α-crystallin (ACR) protein. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) was also adopted to analyze the protein mass spectra. A total of 6 prominent ion signals were observed, including ESAT-6 protein peaks at mass-to-charge ratios (m/z) of ∼7931, ∼7974, ∼9768, and ∼9813 and CFP-10 protein peaks at m/z of ∼10 100 and ∼10 660. The ESAT-6 ion signals were always detected concurrently with CFP-10 ion signals, but CFP-10 ion signals could be detected alone without the ESAT-6 ion signals. Furthermore, the newly found ESAT-6 peaks were also confirmed using a Mag-Beads-Protein G kit with an ESAT-6 antibody to capture the ESAT-6 protein, which was also consistent with the sequence coverage analysis.

Effects of mechanical properties of carbon-based nanocomposites on scaffolds for tissue engineering applications: a comprehensive review.

Mechanical properties, such as elasticity modulus, tensile strength, elongation, hardness, density, creep, toughness, brittleness, durability, stiffness, creep rupture, corrosion and wear, a low coefficient of thermal expansion, and fatigue limit, are some of the most important features of a biomaterial in tissue engineering applications. Furthermore, the scaffolds used in tissue engineering must exhibit mechanical and biological behaviour close to the target tissue. Thus, a variety of materials has been studied for enhancing the mechanical performance of composites. Carbon-based nanostructures, such as graphene oxide (GO), reduced graphene oxide (rGO), carbon nanotubes (CNTs), fibrous carbon nanostructures, and nanodiamonds (NDs), have shown great potential for this purpose. This is owing to their biocompatibility, high chemical and physical stability, ease of functionalization, and numerous surface functional groups with the capability to form covalent bonds and electrostatic interactions with other components in the composite, thus significantly enhancing their mechanical properties. Considering the outstanding capabilities of carbon nanostructures in enhancing the mechanical properties of biocomposites and increasing their applicability in tissue engineering and the lack of comprehensive studies on their biosafety and role in increasing the mechanical behaviour of scaffolds, a comprehensive review on carbon nanostructures is provided in this study.

Циклические испытания вязкоупругих высокоэластичных материалов по программе «Вложенных циклов»

Experimental studies of the viscoelastic properties of elastomeric nanocomposites based on styrene-butadiene rubber and binary filler (carbon black and detonation nanodiamonds) were carried out. In order to most effectively identify the features of the viscoelastic behavior of these materials (which depend not only on the deformation but also on its rate), we used a special test program with ‘nested cycles’ developed at the Institute of Continuous Media Mechanics of the Ural Branch of the Russian Academy of Sciences. During testing, the sample is subjected to uniaxial cyclic loading with the amplitude and rate of deformation decreasing at each step. At the beginning and end of the cycle (i.e., at minimum and maximum cyclic deformations), the grips of the tensile testing machine are stopped for a fixed period of time to measure relaxation dependences. Such an approach allows obtaining the maximum amount of information about both viscous and elastic properties of the tested material in one experiment. The mass content of nanodiamond particles in all samples was the same (7 parts by mass), the proportion of carbon black varied (23, 33 and 43 parts by mass). The equilibrium stress-strain curves (which are very important for theorists for constructing the governing rheological equations) were calculated based on experimental relaxation dependences (stress versus time). An analysis of stress-strain loading curves made it possible to obtain concentration dependences of mechanical characteristics such as maximum and minimum cyclic stresses, initial, minimum and maximum moduli for the first loading curve (elastic properties), hysteresis of cyclic losses (viscous properties at different loading rates). The Mullins softening effect (a drop in elastomer stiffness after the first loading cycle) was also studied.

Synergistic Enhancement of Thermal Conductivity Through Nano Diamond Coordinated Boron Nitride

Synergistic Enhancement of Thermal Conductivity Through Nano Diamond Coordinated Boron Nitride

Lanthanide-modified graphene oxide and nanodiamond materials and their cytotoxicity

Integrating lanthanide elements with carbon-based nanomaterials results in the creation of hybrid materials and nanocomposites with unique properties. We report a functionalization approach free of organic solvents for modifying graphene oxide (GO) and nanodiamond (ND) with various lanthanides (La(III), Ce(III), Eu(III), Gd(III), Tb(III) and Ho(III)). The aqueous-phase impregnation with their acetates was followed first by drying at 80 °C and then by heating at 300 °C for 2 h in air conditions. Scanning electron microscopy revealed that after the initial drying, the samples exhibited the presence of larger lanthanide-containing particles, whereas after the heating at 300 °C they became indistinguishable, and thus the lanthanide species became more homogeneously distributed throughout GO and ND. The toxicity, which is commonly associated with the presence of lanthanides, was evaluated in terms of the ability to inhibit the proliferation of COS-7 monkey kidney cell cultures. Most composites demonstrated a dose-dependent toxicity, with significantly lower cytotoxic effects compared to both the thermally treated GO and ND, as well as the pristine GO. The composites functionalized with gadolinium were among the least toxic at the maximum tested concentration (100 µg/ml). The ND-based composites were not cytotoxic at 50 µg/ml, the lowest tested concentration.

The Influence of UV-Ozone, O2 Plasma, and CF4 Plasma Treatment on the Droplet-Based Deposition of Diamond Nanoparticles.

Surface treatment is critical for homogeneous coating over a large area and high-resolution patterning of nanodiamond (ND) particles. To optimize the interaction between the surface of a substrate and the colloid of ND particles, it is essential to remove hydrocarbon contamination by surface treatment and to increase the surface energy of the substrate, hence improving the diamond film homogeneity upon its deposition. However, the impact of substrate surface treatment on the properties of coatings and patterns is not fully understood. This study explores the impact of UV-ozone, O2 plasma, and CF4 plasma treatments on the wetting properties of the fused silica glass substrate surface. We identify the optimal time interval between the treatment and subsequent ND coating/patterning processes, which were conducted using inkjet printing and ultrasonic spray coating techniques. Our results showed that UV-ozone and O2 plasma resulted in hydrophilic surfaces, while CF4 plasma treatment resulted in hydrophobic surfaces. We demonstrate the use of CF4 plasma treatment before inkjet printing to generate high-resolution patterns with dots as small as 30 μm in diameter. Ultrasonic spray coating showed homogeneous coatings after using UV-ozone and O2 plasma treatment. The findings of this study provide valuable insights into the hydrocarbon airborne contamination on cleaned surfaces over time even in clean-room environments and have a notable impact on the performance of liquid coatings and patterns. We highlight the importance of timing between the surface treatment and printing in achieving high resolution or homogeneity.

Plasticity in diamond nanoparticles: dislocations and amorphization during loading and dislocation multiplication during unloading

Plasticity in diamond nanoparticles: dislocations and amorphization during loading and dislocation multiplication during unloading

Synergistic lubrication mechanism of nanodiamonds with organic friction modifier

Nanoparticles and organic friction modifiers (OFMs) as lubricant additives have shown great potential in friction and wear reduction by forming tribofilms which prevent direct contact at the sliding interface. Potential mechanisms for the formation of these tribofilms remain poorly understood, limiting the ability to optimise the performance of the entire tribosystem. Incorporation of nanoparticles and OFM together in a lubricant could provide a unique solution to enhance frictional and wear properties. In this study, Nanodiamonds (NDs) and Glycerol Monooleate (GMO) have been added to a PAO base oil containing low concentration of Zinc dialkyl dithio-phosphate (ZDDP) to produce a novel lubricant combination that significantly reduces coefficient of friction (COF) and wear. Experimental studies showed that NDs reacted with additives present in the lubricant combination to expedite tribofilm formation. Friction reduction performance can be attributed to the encapsulation of carboxylated NDs due to tribochemical interaction with GMO, their mechanical interlocking in the tribofilm and polishing effect of NDs. The visible presence of NDs in tribofilms and the formation of a thicker tribofilm layer with NDs have been corroborated for the first time in this study. Synergy achieved among NDs, GMO, and low concentration ZDDP to formulate a novel environmentally friendly lubricant with advanced tribological performance has been shown, providing a great potential to develop sustainable tribological solutions for a wide variety of engineering applications.

Dispersion mechanism of nanoparticles and its role on mechanical, thermal and electrical properties of epoxy nanocomposites - A Review

The combined effect of nano-reinforcements on the mechanical performance of nanocomposites, which are a novel class of epoxy matrix hybrid nanocomposites containing multiwall carbon nanotubes (MWCNT), graphene, and nanodiamonds (NDs), is drawing substantial attention from many research communities. The discussion concentrates on the dispersion techniques adopted for the preparation of epoxy composites containing different types of nanoparticles (3-D fillers, nanofibers, nanotubes, and plate-like fillers). This review paper covers the electrical, thermal, and mechanical properties of carbon nanotubes (CNTs), graphene, and nanodiamond-reinforced epoxy nanocomposites and correlates them with the topographical features, morphology, weight fraction, dispersion state, and surface functionalization of CNTs, graphene, and nanodiamond. This review paper also summarises recent developments in the dispersion method of different carbon nanoparticles in epoxy matrix.

Sensitive and Selective Electrochemical Sensor for Antimony Using Boron-doped Diamond Nanoparticles

Sensitive and Selective Electrochemical Sensor for Antimony Using Boron-doped Diamond Nanoparticles

Ground and excited state charge transfer at aqueous nanodiamonds.

Nanodiamonds (NDs) are unique carbonaceous materials with exceptionally high stability, hardness, and notable electronic properties. Their applications in photocatalysis, biomedicine, and energy materials are usually carried out in aqueous environments, where they interact with aqueous adsorbates. Especially, electron density may rearrange from the diamond material toward oxidative adsorbates such as oxygen, which is known as charge transfer doping. In this article, we quantify the charge transfer doping for NDs with inhomogeneous surface coverings (hydroxyl, fluorine, and amorphous carbon), as well as NDs doped with heteroatoms (B, Si, N) using hybrid density functional theory (DFT) calculations. The transfer doping magnitude is largely determined by the NDs' highest occupied molecular orbital energies, which can in turn be modified by the surface covering and doping. However, local modifications of the ND structures do not have any local effects on the magnitude of the charge transfer. We furthermore analyze the impact of aqueous adsorbates on the excited states of an aqueous ND in the context of photocatalysis via time-dependent DFT. Here, we find that the excited electrons are biased to move in the direction of the respective oxidative adsorbate. Surprisingly, we find that also unreactive species such as nitrous oxide may attract the excited electrons, which is probably due to the positive partial charge that is induced by the local N O solvation geometry.

Improved assessment sensitivity of time-varying cavitation events based on wavelet analysis

Ultrasonic cavitation, characterized by the oscillation or abrupt collapse of cavitation nuclei in response to ultrasound stimulation, plays a significant role in various applications within both industrial and biomedical sectors. In particular, inertial cavitation (IC) has garnered considerable attention due to the resulting mechanical, chemical, and thermal effects. Passive cavitation detection (PCD) has emerged as a valuable technique for monitoring this procedure. While the fast Fourier transform (FFT) is a widely used algorithm to analyze IC-induced broadband noise detected by PCD system, it may not adequately capture the time-varying instability of cavitation due to potential nuclei collapse during ultrasound irradiation. In contrast, the continuous wavelet transform offers a more flexible approach, enabling more sensitive analysis of signals with varying frequencies over time. In this study, nanodiamond (ND) and its derivative, nitro-doped nanodiamond (N-AND), known to possess cavitation potential from previous research, were chosen as the source of cavitation nuclei. The cavitation signals detected by PCD were subjected to both FFT and wavelet analyses, with their results comprehensively compared. This research showcased the feasibility of employing wavelet analysis for effective inertial cavitation evaluation. It provided the advantage of monitoring the temporal evolution of cavitation events in real-time, enhancing sensitivity to weak and unstable cavitation signals, especially those in higher order components (3rd and 4th order). Additionally, it yielded a higher level of precision in determining IC thresholds and doses. Furthermore, the inclusion of time information through wavelet analysis offered insights into the limitations of low-cycle ultrasound in inducing IC. This study introduces a novel perspective for more sensitive and precise cavitation assessment, leveraging time and frequency data from wavelet analysis, and holds promise for effective utilization of cavitation effects while minimizing losses and damages resulting from unintended cavitation events.

Nanodiamond-Enhanced Magnetic Resonance Imaging.

Nanodiamonds (ND) hold great potential for diverse applications due to their biocompatibility, non-toxicity, and versatile functionalization. Direct visualization of ND by means of non-invasive imaging techniques will open new venues for labeling and tracking, offering unprecedented and unambiguous detection of labeled cells or nanodiamond-based drug carrier systems. The structural defects in diamonds, such as vacancies, can have paramagnetic properties and potentially act as contrast agents in magnetic resonance imaging (MRI). The smallest nanoscale diamond particles, detonation ND, are reported to effectively reduce longitudinal relaxation time T1 and provide signal enhancement in MRI. Using in vivo, chicken embryos, direct visualization of ND is demonstrated as a bright signal with high contrast to noise ratio. At 24 h following intravascular application marked signal enhancement is noticed in the liver and the kidneys, suggesting uptake by the phagocytic cells of the reticuloendothelial system (RES), and in vivo labeling of these cells. This is confirmed by visualization of nanodiamond-labeled macrophages as positive (bright) signal, in vitro. Macrophage cell labeling is not associated with significant increase in pro-inflammatory cytokines or marked cytotoxicity. These results indicate nanodiamond as a novel gadolinium-free contrast-enhancing agent with potential for cell labeling and tracking and over periods of time.

Basic properties of hydrogenated detonation nanodiamonds

The paper is devoted to basic properties study of hydrogenated detonation nanodiamonds. It is shown that a powder of detonation nanodiamond annealed in molecular hydrogen contains carbonate and bicarbonate ions. These anions may be replaced for other anions during the interaction of the nanodiamond particles with aqueous solutions of salts and acids. The anion replacement is confirmed by Infrared and Energy dispersive X-ray spectroscopies. The presence of carbonate and bicarbonate ions indicates that the hydrogenated diamond nanoparticles have a positive surface charge in the powder according surface transport doping. Potentiometric titration and nitrogen adsorption methods have been used to calculate the surface charge of the particles.