Surface Coatings Research Articles

Biosynthesized silver nanoparticles prevent bacterial infection in chicken egg model and mitigate biofilm formation on medical catheters.

Investigating the application of innovative antimicrobial surface coatings on medical devices is an important field of research. Many of these coatings have significant drawbacks, including biocompatibility, coating stability and the inability to effectively combat multiple drug-resistant bacteria. In this research, we developed an antibiofilm surface coating for medical catheters using biosynthesized silver nanoparticles (b-Cs-AgNPs) developed using leaves extract of Calliandra surinamensis. Various characterization techniques were employed to thoroughly characterize the synthesized b-Cs-AgNPs and c-AgNPs. b-Cs-AgNPs were compatible with human normal kidney cells and chicken embryos. It did not trigger any skin inflammatory response in in vivo rat model. b-Cs-AgNPs demonstrated potent zone of inhibition of 19.09mm when subjected to the disc diffusion method in E. coli confirming strong antibacterial property. Different anti-bacterial assays including liquid growth curve, colony counting assay, biofilm formation assay supported the potent antimicrobial efficacy of b-Cs-AgNPs alone and when coated to medical grade catheters. Mechanistic studies reveal the presence of ferulic acid, that was important for the synthesis of b-AgNPs along with enhanced antibacterial effects of b-Cs-AgNPs compared to c-AgNPs, supported by molecular docking analysis. These results together demonstrated the effective role b-Cs-AgNPs in combating infections and mitigating biofilm formations, highlighting their need for further study in the field of biomedical applications.

Dry wear and corrosive wear behavior of laser-cladded Co19.6Cr19.6Fe19.6Ni19.6(B13.72Si5.88)19.6Y2 and Fe43.6Ni17.4Cr9Co6B17.5Si1.5Nb5 coatings

Corrosive wear is a key factor affecting the safe operation of offshore engineering equipment. In this study, Co19.6Cr19.6Fe19.6Ni19.6(B13.72Si5.88)19.6Y2 and Fe43.6Ni17.4Cr9Co6B17.5Si1.5Nb5 coatings were prepared on the surface of 304 stainless steel using laser cladding technology. Dry wear and corrosive wear behavior of both coatings and 304 stainless steel were comparatively studied under different loads. The results show that both coatings are mainly composed of FCC solid solution, boride, and Laves phases. The average microhardness of Co19.6Cr19.6Fe19.6Ni19.6(B13.72Si5.88)19.6Y2 and Fe43.6Ni17.4Cr9Co6B17.5Si1.5Nb5 coatings are 578.6 HV0.2 and 632.5 HV0.2, respectively. The dry wear resistance of Fe43.6Ni17.4Cr9Co6B17.5Si1.5Nb5 coating is approximately 3 times that of 304 stainless steel under all friction load conditions. It can be found that the Fe43.6Ni17.4Cr9Co6B17.5Si1.5Nb5 coating with high hardness is less sensitive to friction load changes during dry wear process. In 3.5 wt% NaCl solution, the corrosive wear resistance of CoCrFeNiBSiY coating under friction loads of 30 N and 50 N is 2.68 times and 2.83 times that of 304 stainless steel, respectively. The excellent corrosive wear resistance performance of the CoCrFeNiBSiY coating is mainly attributed to its superior corrosion resistance and repassivation ability. During the corrosive wear process, a dense passivation film is formed on the surface of both coatings, which significantly reduces their friction coefficient and volume loss rate.

Directed Assembly of Elastic Fibers via Coacervate Droplet Deposition on Electrospun Templates.

Elastic fibers provide critical elasticity to the arteries, lungs, and other organs. Elastic fiber assembly is a process where soluble tropoelastin is coacervated into liquid droplets, cross-linked, and deposited onto and into microfibrils. While much progress has been made in understanding the biology of this process, questions remain regarding the timing of interactions during assembly. Furthermore, it is unclear to what extent fibrous templates are needed to guide coacervate droplets into the correct architecture. The organization and shaping of coacervate droplets onto a fiber template have never been previously modeled or employed as a strategy for shaping elastin fiber materials. Using an in vitro system consisting of elastin-like polypeptides (ELPs), genipin cross-linker, electrospun polylactic-co-glycolic acid (PLGA) fibers, and tannic acid surface coatings for fibers, we explored ELP coacervation, cross-linking, and deposition onto fiber templates. We demonstrate that integration of coacervate droplets into a fibrous template is primarily influenced by two factors: (1) the balance of coacervation and cross-linking and (2) the surface energy of the fiber templates. The success of this integration affects the mechanical properties of the final fiber network. Our resulting membrane materials exhibit highly tunable morphologies and a range of elastic moduli (0.8-1.6 MPa) comparable to native elastic fibers.

Recent Developments in Slippery Liquid-Infused Porous Surface Coatings for Biomedical Applications.

Slippery liquid-infused porous surface (SLIPS), inspired by the Nepenthes pitcher plant, exhibits excellent performances as it has a smooth surface and extremely low contact angle hysteresis. Biomimetic SLIPS attracts considerable attention from the researchers for different applications in self-cleaning, anti-icing, anticorrosion, antibacteria, antithrombotic, and other fields. Hence, SLIPS has shown promise for applications across both the biomedical and industrial fields. However, the manufacturing of SLIPS with strong bonding ability to different substrates and powerful liquid locking performance remains highly challenging. In this review, a comprehensive overview of research on SLIPS for medical applications is conducted, and the design parameters and common fabrication methods of such surfaces are summarized. The discussion extends to the mechanisms of interaction between microbes, cells, proteins, and the liquid layer, highlighting the typical antifouling applications of SLIPS. Furthermore, it identifies the potential of utilizing the controllable factors provided by SLIPS to develop innovative materials and devices aimed at enhancing human health.

Copper-phenolic coating constructed on silicone urinary catheters to prevent catheter-associated infections

Catheter-associated infections (CAIs) are serious issues in clinics, significantly affecting patient morbidity, mortality, and incurring substantial treatment costs. Hence, the development of a novel strategy to endow surfaces with antibacterial function is particularly important for catheter materials. In this work, Tannic acid (TA) and various concentrations of copper (Cu) were used to construct metal-phenolic network (MPN) coatings to impart silicone catheters antibacterial surfaces (TA/Cu5, TA/Cu5 and TA/Cu25). The prepared copper-phenolic coatings exhibited desirable biocompatibility towards mammalian cells and remarkable antibacterial properties against Staphylococcus aureus (S. aureus), Escherichia coli (E. coli) and even “superbug” such as methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE). The antibacterial properties of the MPN coatings were attributed to the combined effects of Cu and TA. Among all MPN coated silicone catheters, TA/Cu25 (10 mM TA and 250 mM CuCl2·2 H2O) exhibited the highest antibacterial activity with killing ratios of 99.84%, 98.67%, 99.85%, and 99.90% against S. aureus, E. Coli, MRSA and VRE, respectively. Thus, the MPN has significant potential for developing antibacterial surface coatings for silicone catheters, which can effectively mitigate CAIs.

Interatomic potentials for graphene reinforced metal composites: Optimal choice

Graphene reinforced metal matrix composites represent a promising class of materials for high-strength surface coatings because of their high strength and ductility. This study reports the application of different interatomic potentials to correctly describe the interaction between graphene and metals (Al, Cu, Ni, and Ti) by molecular dynamics. Both simple pair potentials, such as Lennard-Jones and Morse, and many-body potentials, such as bond order potential are applied for the simulation of a graphene/metal system at room temperature. Three different structures are considered: (i) graphene interacting with one metal atom; (ii) graphene interacting with a metal nanoparticle, and (iii) three-dimensional graphene network filled with metal nanoparticles. We first determine the potential energy that any graphene/metal system can reach during exposure at 300 K; then, we analyze the interaction dynamics for all considered systems and all potentials. A considerable difference in the interaction between metal nanoparticles with planar and folded graphene was found. For graphene/Ni, graphene/Cu, and graphene/Ti, the Lennard-Jones and Morse potentials provide accurate energetic and structural properties of the studied structures; they also describe interaction in the graphene/metal system in a similar way, at variance with bond-order potential. For graphene/Al, the Tersoff and Morse potentials describe the interaction better than Lennard-Jones. For the simulation of graphene/Me system, the optimal choice of the potential for different structures is of crucial importance. The presented analysis of the interatomic potentials appears to be promising for realistic and accurate simulations of graphene reinforced metal composites.

Diamond-like carbon conversion surfaces for space applications

We present diamond-like carbon (DLC) conversion surfaces to detect particles with energy below 2 keV. Conversion surfaces have been widely applied in measurements of low-energy particles by instruments onboard planetary and heliophysics missions. Their effectiveness is characterized by the efficiency in changing the charge state of the incident particles while maintaining a narrow angular distribution for the reflected particles. DLC as a conversion surface coating material has high conversion efficiency. We developed a conversion surface production process that provides ultra-smooth and ultra-thin DLC conversion surfaces. The process includes substrate preparation through precision cleaning, plasma immersion ion deposition of the DLC film, and diagnostics of the film parameters. The latter includes the measurement of the coating thickness, surface roughness, and the conversion efficiency for ion beams with energy below 2 keV. The process we developed provides the DLC conversion surface coating of repeatable parameters with a mean surface roughness of 3.4 ± 0.2 Å and a mean film thickness of 46.7 ± 0.8 nm uniform across the sample area. Ion beam measurements showed a negative ion yield of 1%–2% for hydrogen atoms and 8%–15% for oxygen atoms with an angular scatter distribution of 10°–20° at full width of half maximum. These results agree with those of other conversion surface coatings in the literature. The DLC conversion surfaces presented here are implemented in the conversion surface subsystem of the Interstellar Mapping and Acceleration Probe (IMAP)-Lo instrument of the IMAP mission scheduled for launch in 2025.

Toxicological analysis of chronic exposure to polymeric nanocapsules with different coatings in Drosophila melanogaster

Nanotechnology involves the utilization of nanomaterials, including polymeric nanocapsules (NCs) that are drug carriers. For modify drug release and stability, nanoformulations can feature different types of polymers as surface coatings: Polysorbate 80 (P80), Polyethylene glycol (PEG), Chitosan (CS) and Eudragit (EUD). Although nanoencapsulation aims to reduce side effects, these polymers can interact with living organisms, inducing events in the antioxidant system. Thus far, little has been described about the impacts of chronic exposure, with Drosophila melanogaster being an in vivo model for characterizing the toxicology of these polymers. This study analyzes the effects of chronic exposure to polymeric NCs with different coatings. Flies were exposed to 10, 50, 100, and 500 μL of NCP80, NCPEG, NCCS, or EUD. The survival rate, locomotor changes, oxidative stress markers, cell viability, and Nrf2 expression were evaluated. Between the coatings, NCPEG had minimal effects, as only 500 μL affected the levels of reactive species (RS) and the enzymatic activities of catalase (CAT) and glutathione S-transferase (GST) without reducing Nrf2 expression. However, NCEUD significantly impacted the total flies killed, RS, CAT, and Superoxide dismutase from 100 μL. In part, the toxicity mechanisms of these coatings can be explained by the imbalance of the antioxidant system. This research provided initial evidence on the chronic toxicology of these nanomaterials in D. melanogaster to clarify the nanosafety profile of these polymers in future nanoformulations. Further investigations are essential to characterize possible biochemical pathways involved in the toxicity of these polymeric coatings.

Visible-Photocatalytic performance of TiO2 particles simply achieved by surface nitridation and coatings fabricated by electrophoretic deposition (EPD) process

Originally, surface-nitridated TiO2 particles were prepared by urea decomposition under hydrothermal treatment. After the surface nitridation, the absorption onset was extended to the visible region due to narrowed band gap of ∼ 3.10 eV comparable to that of ∼ 3.28 eV for pristine TiO2. Due to narrowed band gap, the surface-nitridated TiO2 distinguishably had the visible photocatalytic ability under 440 nm. The visible-photocatalytic nitridated TiO2 particles was successfully fabricated as dense coatings with controllable transparency by electrophoretic deposition (EPD) process.

Simultaneous Dopamine and Serotonin Monitoring in Freely Moving Crayfish Using a Wireless Electrochemical Sensing System.

Dopamine (DA) and serotonin (5-HT) are neurotransmitters that regulate a wide range of physiological and behavioral processes. Monitoring of both neurotransmitters with real-time analysis offers important insight into the mechanisms that shape animal behavior. However, bioelectronic tools to simultaneously monitor DA and 5-HT interactive dynamics in freely moving animals are underdeveloped. This is mainly due to the limited sensor sensitivity with miniaturized electronics. Here, we present a semi-implantable electrochemical device achieved by integrating a multi-surface-modified carbon fiber microelectrode with a miniaturized potentiostat module to detect DA and 5-HT in vivo with high sensitivity and selectivity. Specifically, carbon fiber microelectrodes were modified through electrochemical treatment and surface coatings to improve sensitivity, selectivity, and antifouling properties. A customized, lightweight potentiostat module was developed for untethered electrochemical measurements. Integrated with the microelectrode, the microsystem is compact (2.8 × 2.3 × 2.1 cm) to minimize its impacts on animal behavior and achieved simultaneous detection of DA and 5-HT with sensitivities of 48.4 and 133.0 nA/μM, respectively, within submicromolar ranges. The system was attached to the crayfish dorsal carapace, allowing electrode implantation into the heart of a crayfish to monitor DA and 5-HT dynamics, followed by drug injections. The semi-implantable biosensor system displayed a significant increase in oxidation peak currents after DA and 5-HT injections. The device successfully demonstrated the application for in vivo simultaneous monitoring of DA and 5-HT in the hemolymph (i.e., blood) of freely behaving crayfish underwater, yielding a valuable experimental tool to expand our understanding of the comodulation of DA and 5-HT.

Elastic and Elastoplastic Contact Mechanics of Concentrated Coated Contacts

Machines operate under increasingly harsher contact conditions, causing significant wear and contact fatigue. Sub-surface stresses are responsible for the premature contact fatigue of rolling element bearings, meshing gears, and cam–follower pairs. Surface protection measures include hard, wear-resistant coatings. Traditionally, contact integrity has been predicted using classical Hertzian contact mechanics. However, the theory is only applicable when the contact between a pair of ellipsoidal solids of revolution may be considered as a rigid indenter penetrating a semi-infinite elastic half-space. Many coatings act as thin bonded elastic layers that undergo considerably higher pressures than those predicted by the classical theory. Furthermore, inelastic deformation of bonded solids can cause plastic flow, work-hardening, and elastoplastic behaviour. This paper presents a comprehensive, integrated contact mechanics analysis that includes induced sub-surface stresses in concentrated counterformal finite line contacts for all the aforementioned cases. Generated pressures and deformation are predicted for hard coated surfaces, for which there is a dearth of relevant analysis. The contact characteristics, which are of particular practical significance, of many hard, wear-resistant advanced coatings are also studied. The paper clearly demonstrates the importance of using efficient semi-analytical, detailed holistic contact mechanics rather than the classical idealised methods or empirical numerical ones such as FEA. The novel approach presented for the finite line contact of thin-layered bonded solids has not hitherto been reported in the open literature.

Silica Surface Coating of Blue Light-Emitting CsPbBr3 Nanoplatelets for Improved Stability in Polar Solvents and Long-Term Storage

Silica Surface Coating of Blue Light-Emitting CsPbBr₃ Nanoplatelets for Improved Stability in Polar Solvents and Long-Term Storage

Predicted Fracture Tendency of Naturally Occurring Aluminum Surface Coatings under Tensile Loading.

Naturally occurring coatings on aluminum metal, such as its oxide or hydroxide, serve to protect the material from corrosion. Understanding the conditions under which these coatings mechanically fail is therefore expected to be an important aspect of predictive models for aluminum component lifetimes. To this end, we develop and apply a molecular dynamics (MD) modeling framework for conducting tension tests that is capable of isolating factors governing the mechanical strength as a function of coating chemistry, defect morphology, and variables associated with the loading path. We consider two representative materials, including γ-Al2O3 and γ-Al(OH)3 (i.e., oxide and hydroxide), both of which form readily as aluminum surface coatings. Our results indicate that defects have a significant bearing on the strength of aluminum oxide, with grain boundaries serving to reduce the strain at failure from εzz = 0.300 to 0.219, relative to perfect single crystal. Our simulations also predict that porosity lowers the elastic stiffness and yield strength of the oxide. Relative to perfect crystal, we find porosity factors of 5%, 10% and 20% decrease the yield stress by 26%, 36% and 53%, respectively. MD predicts that perfect hydroxide and oxide single crystal have respective strains at failure of 0.08 and 0.31 under tensile uniaxial strain loading, and that the corresponding yield stresses are respectively 1.6 and 11.1 GPa. These data indicate that the hydroxide is substantially more susceptible to mechanical failure than the oxide. Our results, coupled with literature findings that indicate hot and humid conditions favor formation of hydroxide and defective oxide coatings, indicate the potential for a complicated dependence of aluminum corrosion susceptibility and stress corrosion cracking on aging history.

The Possible Control Method of Turn-to-Turn Contact Resistivity of REBCO Coil by Surface Coating

The Possible Control Method of Turn-to-Turn Contact Resistivity of REBCO Coil by Surface Coating

Carbon bridge effects regulate TiO2-acrylate fluoroboron coatings for efficient marine antifouling

Synergy strategy of photocatalysts and polymer resins are promising technology for marine antifouling. However, it is still a main challenge to obtain a green, safe, and efficient antifouling coatings. Herein, carbon (graphene or CNT) modified TiO2 photocatalyst was synthesized via hydrothermal and annealing process and has successfully applied in acrylate fluoroboron polymer (ABFP) composite coating. Morphology and chemical composition were detailed characterized. The graphene or CNT acted as a bridge with supplemental spatial structures (petal gaps, entanglement) and new functional groups (C-O, C-Ti-O, etc.) on TiO2 particle. Carbon nanotube (CNT) modified TiO2-ABFP coatings (BTCP) achieved excellent antibacterial and anti-diatom adhesion rate of 89.33%-96.70% and 99.00%-99.50%, which was 1.84-4.94-fold more than that of the single ABFP. CNT or graphene served as electronic bridges was considered as the crucial mechanism, which significantly improved the light absorption range and capacity, conductivity, and photoelectric response of TiO2, and further accelerated the generation and transfer of free radicals to the surface of BTCP or FTGP. Moreover, the improvement of catalyst activity synergizes with the smooth surface, hydrophilicity, and slow hydrolysis of composite coatings, achieved long-term and efficient antifouling performance. This work provides a new insight into the modification of TiO2 and antifouling mechanism of polymer coating.

Tribological properties of HFCVD diamond coatings over wide temperature range

Single and gradient multilayered diamond coatings, deposited on silicon nitride (Si3N4), were prepared by hot filament chemical vapour deposition. The tribological properties were evaluated in a wide temperature range (26 °C–300 °C), against Si3N4 ceramic balls, as the friction counterpart. The results showed that with the increase of temperature from 26 °C to 300 °C, the wear rate of NCD (nanocrystalline diamond) and GCD (gradient diamond) coatings rapidly increases. When the temperature reaches 300 °C, obvious cracks and detachment appear on the surface of the NCD coatings. Due to the special interlayer, the wear rate of the GCD coatings is lower than that of the NCD coatings. In the range of 26 °C to 100 °C, GCD exhibits excellent wear resistance and low friction coefficient due to its special gradient structure. When the temperature increases to 200 °C, NCD films with smaller grain sizes exhibit higher wear rates. From the wear morphology, it can be seen that cracks are generated in the NCD film, and as the temperature increases, the cracks continue to expand until the film spalling. GCD shows relatively good wear resistance at high temperatures. This study found that gradient multilayered diamond coatings exhibited superior wear resistance at high temperatures, compared with single-layer coatings tested in identical conditions.

Impact of absorber surface coatings on the thermal performance of non-concentrating solar thermal collectors: An overview

In this critical evaluation, the impact of absorber surface coating on the thermal efficiency (%) of non-concentrating solar thermal collectors (STCs) is examined and discussed. Absorber surface coatings enable an almost instantaneous conversion of solar radiation into heat. To achieve high sunlight absorption capacity and low solar emittance, several types of selective solar coatings are continually being developed. This review article offers a novel aspect based on extensive research that has been published in the past related to the impact of absorber surface coating on the thermal performance of non-concentrating STCs. The article demonstrates the commonalities in the results by thoroughly evaluating all the coating types that have the potential to influence STC's performance. An exhaustive examination of the available research from several studies shows that absorber surface coating enhances the STC absorber's capacity to absorb heat.

Enhanced Pool Boiling Heat Transfer with Porous Ti-6Al-4V-Coatings Produced by Cold Spray Metal Additive Manufacturing

In advancing industrial heat transfer mechanisms, surface coatings offer significant potential. This research elucidates the efficacy of the metal additive manufacturing Cold Spray deposition technique for producing enhanced boiling surfaces, specifically focusing on Ti-6Al-4V (Ti64) coatings on Aluminium substrates. This offers a rapid and low-cost fabrication method for producing lightweight enhanced boiling surfaces. The Cold Spray method is typically used to create dense metal deposits. Here, the process has been specially tuned to create highly inhomogeneous honeycomb-type porous Ti64 coatings. Critical Cold Spray deposition parameters, such as particle velocity, preheat temperature, and deposition rate have been identified to create repeatable porous coatings, with thicknesses of up to 3.0 mm achievable. Following deposition, several samples were subjected to systematic boiling heat transfer tests in a purpose-built pool boiling apparatus. Boiling curves were generated for the augmented Cold Spray surfaces as well as a bare surface, with the latter acting as a baseline to which enhancement levels were assessed. Initial data analysis shows that some of the tested surfaces exhibit a notable increase in boiling heat transfer coefficient and Critical Heat Flux (CHF). This enhancement is potentially attributed to increased surface area, increased nucleation site density, capillary wicking, and mitigation of lateral bubble coalescence, though excessive coating thickness may degrade heat transfer. In summary, the novel Ti64 surface structures developed using the Cold Spray deposition technique exhibits high potential for industries necessitating superior boiling heat transfer performance. Importantly, the manufacturing process is industrially scalable, offering the capacity to rapidly coat large areas at low cost compared with subtractive manufacturing other metal additive manufacturing methods.

Surroundings-adaptive coating enabling robustness of magnesium alloys

Magnesium alloys have promising application prospects in aeronautical and aerospace fields, but are susceptible to performance damage. Therefore, it is of great significance to construct surface coatings with surroundings-adaptability to endow magnesium alloys with robustness in harsh environment. Herein, a rare-earth-coating with surroundings-adaptability was prepared on AZ31 magnesium alloy by chemical conversion and stearic-acid modification. The as-constructed coating is composed of the micro-nano-structured lanthanum/magnesium stearate, which is superhydrophobic with a water contact angle of 154.5°. The coating can reduce the icorr value of magnesium alloy by two orders of magnitude. The as-coated sample demonstrates extraordinary self-cleaning performance and strong resistance to various mechanical (tape peeling, friction/wear, sand/rain impact, ultraviolet irradiation) and chemical (acid/salt/alkali, organic solvent, corrosive medium) damage, showcasing remarkable surroundings-adaptability. Such surroundings-adaptability is resulted from the durable superhydrophobicity of the coating, which reduces the contact area between the coating and the harmful mediums. The surroundings-adaptive coating enables robustness of magnesium alloys in harsh environment, which can promote their wide applications in aeronautics and aerospace.

Nanotechnology: “Advancing Material Science and Medicine”

Nanotechnology has been a rapidly growing field of advanced science at the inception of this century. Nanotechnology of advanced materials, polymers, principally revolves around endeavours to plan materials at a sub-atomic level to accomplish alluring properties and applications at a naturally visible level. Nanotechnology can be used for the advancement of technologies, ranging from communication and information, health and medicine, future energy, environment and climate change to transport and cultural heritage, personal protective equipment (PPE), fuels, fuel cells, biosensors, disease sensors etc. Nanomaterials will lead to a new approach to manufacturing materials and devices. Faster computers, advanced pharmaceuticals, controlled drug delivery, biocompatible materials, nerve and tissue repair, crackproof surface coatings, better skin care and protection, more efficient catalysts, better and smaller sensors, even more efficient telecommunication. For example, a low risk solution using antibody modified bismuth nanoparticle, in combination with an X-ray dose equivalent to a chest X-ray specifically, has been shown to kill the common bacterium Pseudomonas aeruginosa in a set up designed to resemble a deep wound in human tissue. Nanosized gold particle could catalyse the oxidation of carbon monoxide better than anything previously known. Heparin functionalized nanoparticles have been use for targeted delivery of anti-malarial drugs. Heparin is abundant and cheap, compared to treatments that involve antibodies, an important consideration, since malaria is most common in developing countries. A bone repairing nano-particle paste has been developed that promises faster repair of fractures and breakages. DNA containing two growth genes is encapsulated inside synthetic calcium phosphate nanoparticles. In a remarkable demonstration of the extreme limits of nanoscale engineering, researchers have used the tip of a scanning tunnelling microscope to cleave and form selected chemical bonds in a complex molecule. Many medicinal and industrial endeavours have seen the use of Nanotechnology. Nanoparticles can attach to SARS COV-2 viruses, disrupting their structure and so kill the virus. These and other more recent advances in nanotechnology will be presented at this conference.