In the question put forward by Scott et al., implications about the role of immune activation in depressive or other mood disorders were suggested. Low-level inflammation, triggered by the release of inflammatory molecules such as cytokines, has been detected in individuals with major mood disorders. These markers can be present in very low concentrations, posing a significant analytical challenge and complicating their use as reliable biomarkers. In this Perspective, we discuss the potential promise in leveraging nanotechnology and trace-level analysis of biomarkers of immune activation to enhance our molecular understanding of the immune system’s functioning and its association with depressive and other mood disorders. This Perspective critically discusses the analytical challenges of trace biomarker detection, highlighting issues with variability in study methodologies and cohort heterogeneity and emphasising the need for diurnal and longitudinal sampling to study circadian disruption and immune activation. Profiling inflammatory markers in this manner could create individualised molecular fingerprints, revealing disruptions in immune synchronisation with circadian rhythms and detecting abnormalities linked to specific mood disorder subtypes, and particularly ‘circadian depression’. As the profiling of general inflammatory markers may not be sufficient to study any causative relationship between immune activation and major mood disorders, we propose the exploration of novel biomarkers such as extracellular vesicles to support these investigations. The use of nanotechnologies for trace profiling of diurnal variations of inflammatory molecules, in combination with novel biomarkers, offers a promising strategy to develop a molecular understanding of the role of immune activation in depressive and other mood disorders.

Homogenisation is a widely used technique in manufacturing powdered milk with a direct impact on product solubility, and the homogenisation pressure is a central attribute of this process. We aimed to understand the effect of increasing homogenisation pressures (0/0, 15/5, and 75/5 MPa, 1st/2nd stages) on particle-size distribution during homogenised whole milk powder manufacture and rehydration of the final product. The fluid milk was thermally treated, homogenised, concentrated by rotary evaporation, and then dried using a spray dryer. Particle size (Dv90) was monitored at all stages of the manufacturing process. The final product (milk powder) was analysed using particle-size distribution, electronic scanning microscopy, water activity, and isotherms. The results demonstrated that increasing the homogenisation pressure leads to milk powder with smaller particle size when rehydrated (Dv90 values: 6.08, 1.48 and 0.64 μm for 0, 20 and 80 MPa, respectively). Furthermore, the volume (%) of the particles in the ‘sub-micro’ region (smaller than 1.0 μm) presented an inversely proportional profile to the homogenisation pressure (homogenised fluid milk: 86.1, 29.3 and 2.4%; concentrated milk: 86.1, 26.5 and 5.7%, and reconstituted milk powder: 84.2, 31.8 and 10.9%). Surprisingly, this pattern was not observed in the SPAN value (which corresponds to the width or range of the size distribution based on the volume). Additionally, the increase in the homogenisation pressure did not affect the sorption isotherm pattern. These results demonstrate that increasing the homogenisation pressure decreases the particle size of the reconstituted powdered milk, indicating the potential for future studies on how this phenomenon affects its physicochemical and final product properties.

In the absence of government safety regulation in the field of nanotechnology, ISO standards are being used as the basis for establishing technical and management guidelines at an international level. There are more than 50 current ISO standards on nanotechnology. Some of these relate to the working environment and occupational risk management. In Latin America, entities that are members of ISO are enunciating national versions of the international standards. In this article, this context is analysed critically, starting from the Mexican standard on occupational risk management in the working environment. Even though risk management standards may guarantee better and safer working conditions, in the field of nanotechnology, they simultaneously unlock detrimental implications for workers and society. Reliance on such private and voluntary forms of industry self-regulation is identified as a by-product of global neoliberalism.

Studies on the effect of nanofertilizers (NF) in physiological performance of plants is scarce, especially that related to substances encapsulated into silicon dioxide (SiO2) nanoparticles in cocoa plants. The effect of foliar application of SiO2-NF on nutrient contents, gas exchange, photochemical activity, photosynthetic pigments, total soluble protein (TSP), photosynthetic nitrogen use efficiency (PNUE), and growth in seedlings of two cocoa clones (OC-61 and BR-05) in a greenhouse was assessed. Spraying with SiO2-NF increased net photosynthetic rate (A) by 16 and 60% and electron transport rate (J) by 52 and 162% in clones OC-61 and BR-05, respectively, without changes in photosynthetic pigment concentration in either clone. The SiO2-NF caused a decrease of 37 and 22% in stomatal conductance in OC-61 and BR-05, respectively; a similar trend was observed in transpiration rate, causing an increase of 42 and 100% in water use efficiency in OC-61 and BR-05, respectively. In both clones, diameter of graft increased on average 28% with SiO2-NF. Higher photosynthetic capacity was related to an increase in leaf N, P, and TSP. A significant reduction in PNUE (A/N ratio) was found in OC-61, whereas in BR-05 PNUE increased after spraying with SiO2-NF. Overall, spraying with SiO2-NF had a positive effect on photosynthetic processes in both cocoa clones, associated with an increase in nutrients content, which translated into improved growth. A differential physiological response to spraying with SiO2-NF between clones was also found, with BR-05 being the clone with a better physiological response during the establishment and development stages.

This work presents the results of the physical characterization of palygorskite and its adsorptive behaviour for three solvatochromic dyes (Nile blue chloride (NBC), methylene blue (MTB) and dithizone (DTZ)). Adsorption isotherms were used to determine the maximum adsorption of the solvatochromic dyes on the palygorskite. The characterization of palygorskite was carried out via mineralogical and chemical analysis with X-ray diffraction, X-ray fluorescence, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy, surface-charge measurement (ζ-potential), thermogravimetric analysis, textural analysis and cation-exchange capacity analysis. The material consists of palygorskite and quartz and its chemistry is dominated by SiO2, MgO and Fe2O3. The specific surface area and cation-exchange capacity of the palygorskite are 142 m2 g–1 and 41 cmol(+) kg–1, respectively. The SEM and TEM analyses showed a fibrous structure with fibres 20–100 nm long. The thermogravimetric analysis showed three endothermic events at 57.3°C, 171.8°C and 439.6°C. The adsorption capacities of the palygorskite for NBC (basic pH), MTB (basic pH) and DTZ (neutral pH) were 0.082, 0.013 and 0.102 g g–1, respectively. The adsorptions of NBC and MTB were fitted with the Langmuir isotherm model and the adsorption of DTZ was fitted with the Sips model.

Halloysite is a 1:1 dioctahedral clay mineral that has been studied widely for applications in nanotechnology and as a mineral exploration guide for recognizing regolith-hosted heavy rare earth element (HREE) deposits. In Brazil, pegmatites from the state of Rio de Janeiro have been catalogued, but their potential to host halloysite deposits has never been studied. After a mineral exploration programme, one pegmatite with considerable halloysite contents and economic potential was discovered. This study reports the mineralogical and chemical characterization of the halloysite of this pegmatite and evaluates the possibility of clay-adsorbed HREE deposits, like that in the Zudong (China) regolith-hosted HREE deposit. Seven samples were collected in horizontal channels. Bulk samples and clay fractions (<2 μm) were analysed by quantitative mineral analysis (X-ray diffraction/Rietveld method), chemical analysis (major elements by X-ray fluorescence and Y, U, Th and rare earth elements by inductively coupled plasma mass spectrometry), scanning electron microscopy, Fourier-transform infrared spectroscopy, particle-size analysis, nitrogen physisorption and cation-exchange capacity. Mixed polygonal/cylindrical halloysite-7Å in concentrations between 6.3 and 35.4 wt.% in bulk samples and between 58.0 and 89.8 wt.% in the clay fractions were identified in the pegmatite. The clay fractions presented an average chemical composition of 45.46 wt.% SiO2, 36.10 wt.% Al2O3, 14.62 wt.% loss on ignition and 1.04 wt.% Fe2O3, as well as technological properties close to those observed in world-class halloysite deposits such as Dragon Mine (USA) and Matauri Bay (New Zealand). The clay minerals did not present significant HREE contents.

The CytoViva Enhanced Darkfield (EDF) Illuminator enables direct optical observation of nano-scale entities in a wide range of transparent and translucent sample environments, without requiring the use of labels or other markers. The improved performance is a result of a uniquely designed light path, which focuses maximum photon density on the sample, thus enabling superior signal-to-noise imaging performance. This high-performance capability not only provides users with previously unobtainable images, but it also allows established techniques such as hyperspectral and Raman microscopy to be used in new and exciting ways.

The fibrous scaffolds for bone tissue engineering that mimic the extracellular matrix with bioactive and bactericidal properties could provide adequate conditions for regeneration of damaged bone. Electrospun ultrathin fiber covered with nano-hydroxyapatite is a favorable fibrous scaffold design. We developed a fast and reproducible strategy to produce polyvinylidene fluoride (PVDF)/nano-hydroxyapatite (nHAp) nanofibrous scaffolds with bactericidal and bioactive properties. Fibrous PVDF scaffolds were obtained first by the electrospinning method. Then, their surfaces were modified using oxygen plasma treatment followed by electrodeposition of nHAp. This process formed nanofibrous and superhydrophilic PVDF fibers (133.6 nm, fiber average diameter) covered with homogeneous nHAp (202.6 nm, average particle diameter) crystals. Energy-dispersive X-ray spectrometry demonstrated the presence of calcium phosphate, indicating a Ca/P molar ratio of approximately 1.64. X-ray diffraction, Fourier transform infrared spectroscopy, and Raman spectroscopy spectra identified β-phase of nHAp. Thermal analysis indicated a slight reduction in stability after nHAp electrodeposition. Bactericidal assays showed that nHAp exhibited 99.8% efficiency against Pseudomonas aeruginosa bacteria. The PVDF/Plasma and PVDF/nHAp groups had the highest cell viability, total protein, and alkaline phosphatase activity by 7 days after exposure of the scaffolds to MG63 cell culture. Therefore, the developed scaffolds are an exciting alternative for application in bone regeneration.

In this report, atomic force microscopy (AFM) nanolithography and electrochemical anodic oxidation using bias-assisted lithography are used to created oxide patterns on the surface of a silicon substrate. Non-contact mode imaging was conducted after the lithography process to confirm the successful fabrication of oxide patterns on the surface as well as to distinguish the surface difference between the oxide layers and silicon substrate. With only a few seconds of run time, oxide patterns as narrow as 35 nm in width were created illustrating that the bias mode in the Park Scientific SmartLitho software can be used to generate well-defined nanoscale patterns and features.

The two current reigning paradigms enabling nanotechnology are scanning probe microscopy and molecular machine devices that date back to seminal experiments by Eigler and visionary work by Drexler, respectively. The nanoscience and nanotechnology community is seeing the emergence of a third paradigm—the use of the atomically focused beam of a scanning transmission electron microscope (STEM) to control and direct matter on the atomic scale. Beam-induced modifications involving one atom or a small group of atoms can be induced and monitored in real time with atomic resolution. Combined with the development of beam-control electronics, big data acquisition, and analytical tools such as artificial intelligence-based feedback systems, electron and ion microscopies are at the brink of a transition from purely imaging tools to tools capable of creating structures with atomic precision and high throughput. In this issue of MRS Bulletin, we present recent advances in electron- and ion-beam-based atomic fabrication on surfaces, in layered materials, and finally in three dimensions—the ultimate dream and possibly the final frontier of nanoscience.

New oral treatments are needed for all forms of leishmaniasis. Here, the improved oral efficacy of quercetin (Qc) and its penta-acetylated derivative (PQc) was evaluated in cutaneous leishmaniasis after encapsulation in lipid-core nanocapsules (LNCs) of poly(ε-caprolactone). Leishmania amazonensis-infected BALB/c mice were given 51 daily oral doses of free drugs (16 mg kg−1) or LNC-loaded drugs (0·4 mg kg−1). While treatment with free Qc reduced the lesion sizes and parasite loads by 38 and 71%, respectively, LNC-Qc produced 64 and 91% reduction, respectively. The antileishmanial efficacy of PQc was similar but not as potently improved by encapsulation as Qc. None of the treatments increased aspartate aminotransferase, alanine aminotransferase or creatinine serum levels. These findings indicate that when encapsulated in LNC, Qc and, to a lesser extent, PQc can safely produce an enhanced antileishmanial effect even at a 40-fold lower dose, with implications for the development of a new oral drug for cutaneous leishmaniasis.

Despite significant advances in therapies against Trypanosoma evansi, its effective elimination from the central nervous system (CNS) remains a difficult task. The incapacity of trypanocidal drugs to cross the blood–brain barrier (BBB) after systemic administrations makes the brain the main refuge area for T. evansi. Nanotechnology is showing great potential to improve drug efficacy, such as nerolidol-loaded nanospheres (N-NS). Thus, the aim of this study was to investigate whether the treatment with N-NS was able to cross the BBB and to eliminate T. evansi from the CNS. High-performance liquid chromatography revealed that N-NS can cross the BBB of T. evansi-infected mice, while free nerolidol (F-N) neither the trypanocidal drug diminazene aceturate (D.A.) were not detected in the brain tissue. Polymerase chain reaction revealed that 100% of the animals treated with N-NS were negatives for T. evansi in the brain tissue, while all infected animals treated with F-N or D.A. were positives. Thus, we concluded that nanotechnology improves the therapeutic efficacy of nerolidol, and enables the transport of its active principle through the BBB. In summary, N-NS treatment can eliminate the parasite from the CNS, and possesses potential to treat infected animals.