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In this study, systematic analysis of nanotechnology education programmes was carried out from a global and local perspective. Although several universities offer 3-4 year nanotechnology-centred educational programmes, in general the most common modes for nanotechnology education include either modular courses integrated in traditional scientific disciplines or 2-year specialised MSc programmes. Nanotechnology education has a number of peculiarities. For example, it is common to include “nano”-labelling of education for marketing purposes to attract students to study traditional disciplines. Another conclusion of the analysis is that specialised nanotechnology programmes require access to advanced characterisation equipment, which can be limiting for programmes with small number of students. The nanotechnology education in Sweden does not differ much from other countries in its structure. MSc programmes or modular courses in nanotechnology are offered by major universities. Lund University and KTH offer 2-year MSc programmes with specialisation in nanoscience, having strong focus on nanoelectronics and nanophysics, whereas Chalmers is offering nanoelectronics as a part of international 2-year Erasmus Mundus MSc programme in nanoscience and nanotechnology- EMMNano. The nanotechnology education at Uppsala University is conducted mainly through modular courses, with significantly higher number of courses specialised in life sciences applications than that at other major Swedish universities. At this time, it appears that no 2-year MSc programme is offered by major Swedish universities with specialisation in nanomedicine. Finally, extensive analysis of nanotechnology for life science education is conducted to highlight core concepts in the field.

The use of PPE has drastically increased because of the SARS-CoV-2 (COVID-19) pandemic as disposable surgical face masks made from non-biodegradable polypropylene (PP) polymers have generated a significant amount of waste. In this work, a low-power plasma method has been used to degrade surgical masks. Several analytical techniques (gravimetric analysis, scanning electron microscopy (SEM), attenuated total reflection-infra-red spectroscopy (ATR-IR), x-ray photoelectron spectroscopy (XPS), thermogravimetric analysis/differential scanning calorimetry (TGA/DSC) and wide-angle x-ray scattering (WAXS)) were used to evaluate the effects of plasma irradiation on mask samples. After 4 h of irradiation, an overall mass loss of 63 +/- 8%, through oxidation followed by fragmentation, was observed on the non-woven 3-ply surgical mask, which is 20 times faster than degrading a bulk PP sample. Individual components of the mask also showed different degradation rates. Air plasma clearly represents an energy-efficient tool for treating contaminated PPE in an environmentally friendly approach.

A manganese(II) metal-organic framework based on the hexatopic hexakis(4-carboxyphenyl)benzene, cpb6-: [Mn3(cpb)(dmf)3], was solvothermally prepared showing a Langmuir area of 438 m2/g, rapid uptake of sulfur hexafluoride (SF6) as well as electrochemical and magnetic properties, while single crystal diffraction reveals an unusual rod-MOF topology.

The ever-increasing atmospheric CO2 level is considered to be the major cause of climate change. Although the move away from fossil fuel-based energy generation to sustainable energy sources would significantly reduce the release of CO2 into the atmosphere, it will most probably take time to be fully implemented on a global scale. On the other hand, capturing CO2 from emission sources or directly from the atmosphere are robust approaches that can reduce the atmospheric CO2 concentration in a relatively short time. Here, we provide a perspective on the recent development of metal–organic framework (MOF)-based solid sorbents that have been investigated for application in CO2 capture from low-concentration (<10 000 ppm) CO2 sources. We summarized the different sorbent engineering approaches adopted by researchers, both from the sorbent development and processing viewpoints. We also discuss the immediate challenges of using MOF-based CO2 sorbents for low-concentration CO2 capture. MOF-based materials, with tuneable pore properties and tailorable surface chemistry, and ease of handling, certainly deserve continued development into low-cost, efficient CO2 sorbents for low-concentration CO2 capture.

Nanomedicine plays a crucial role in the development of next-generation therapies. The use of nanoparticles as drug delivery platforms has become a major area of research in nanotechnology. To be effective, these nanoparticles must interact with desired drug molecules and release them at targeted sites. The design of these "nanoplatforms" typically includes a functional core, an organic coating with functional groups for drug binding, and the drugs or bioactive molecules themselves. However, by exploiting the coordination chemistry between organic molecules and transition metal centers, the self-assembly of drugs onto the nanoplatform surfaces can bypass the need for an organic coating, simplifying the materials synthesis process. In this perspective, we use gold-iron oxide nanoplatforms as examples and outline the prospects and challenges of using self-assembly to prepare drug-nanoparticle constructs. Through a case study on the binding of insulin on Au-dotted Fe3O4 nanoparticles, we demonstrate how a self-assembly system can be developed. This method can also be adapted to other combinations of transition metals, with the potential for scaling up. Furthermore, the self-assembly method can also be considered as a greener alternative to traditional methods, reducing the use of chemicals and solvents. In light of the current climate of environmental awareness, this shift towards sustainability in the pharmaceutical industry would be welcomed.

The CO2 sorption properties of sodium hafnium oxide (Na2HfO3) were investigated in this study. Na2HfO3 was synthesized by solid-state synthesis using Na2CO3 and HfO2 as starting materials. The solid-state synthesized Na2HfO3 appeared structurally similar to other mixed metal oxides such as Na2ZrO3, but stacking disorder appeared to be common in Na2HfO3. The synthesis conditions, including the Na : Hf ratio (between 0.5 and 1.5 : 1), synthesis temperature, time and heating rate, were investigated to optimize CO2 sorption properties of Na2HfO3. The Na2HfO3 sorbent showed comparable CO2 uptake capacity, reaction rate and excellent cycling stability compared to other metal oxide sorbents. Na2HfO3 with Na : Hf = 1 : 1 and 1.25 : 1 showed the highest CO2 uptake among all Na2HfO3 samples obtained, with a CO2 uptake capacity of around 15 wt% (at 650–800 °C). The CO2 uptake rate of NHO-1 and NHO-1.25 was fast with over 80% of the equilibrium uptake reached within 250 s. Na2HfO3 remained stable even after 100 cycles with less than 3% difference in the CO2 uptake capacity between the 1st and 100th cycles. We performed kinetic analysis on the CO2 sorption data and found that the Avrami–Erofeev model fitted the kinetic data best among the kinetic models used. Apart from sorbent optimization, we showed that 3D-printing of Na2HfO3 : HfO2 mixtures can be used to produce structured Na2HfO3 sorbents with a slightly improved CO2 uptake rate and the same CO2 uptake capacity as the powder-based solid-state synthesized Na2HfO3 sorbent.

For the first time, the use of stannate-based sorbents was investigated as high temperature CO2 sorption to evaluate their potential to contribute towards reducing carbon emissions. The sorption capacity and kinetics of commercial tin oxide, sodium, potassium and calcium stannates and lab synthesised potassium stannates were tested using thermogravimetric analysis. Commercial K2SnO3 was found to possess the largest CO2 uptake capacity (2.77 mmol CO2/g or 12.2 wt%) at 700 °C, which is among the highest for potassium sorbents, but the CO2 desorption was not successful. On the contrary, the in-house synthesised K-stannate (K-B) using facile solid-state synthesis outperformed the other sorbents, resulting in a CO2 uptake of 7.3 wt% after 5 min, an adsorption rate (0.016 mg/s) one order of magnitude higher than the other stannates, and stability after 40 cycles. The XRD and XPS analyses showed that K-B contains a mixture of K2SnO3 (76%) and K4SnO4 (21%), while the Scherrer crystal sizes confirmed good resistance to sintering for the potassium stannates. Among the apparent kinetic model tested, the pseudo-second order model was the most suitable to predict the CO2 sorption process of K-B, indicating that chemical adsorption is dominant, while film-diffusion resistance and intra-particle diffusion resistance governed the sorption process in K-B. In summary, this work shows that solid-state synthesised potassium stannate could be an effective sorbent for high temperature separation, and additional work is required to further elucidate its potential.

Efficient, facile, and energy-efficient desorption processes are highly sought after in industrial processes. Visible light exists all around us and can be considered a ubiquitous energy source that can be used to drive photothermal processes such as the release of guest molecules from porous sorbents. Herein, we present four sustainably synthesized porous coordination polymers, M(dhbq)(H2O)2 (where dhbq = 2,5-dihydroxy-1,4-benzoquinone, and M = Fe, Mg, Mn, or Zn) with visible light photoresponsive properties. Efficient desorption of CO2 corresponding to up to 47.6 % of the total uptake capacity was achieved upon visible light irradiation for 10 min. A negligible decrease (< 97 %) in CO2 uptake was observed for up to 10 light-swing adsorption cycles and working capacities of up to 37.5 g kg- were obtained in Fe(dhbq). M(dhbq) possess highly desirable properties that make them interesting for applications related to cost-effective and energy-efficient desorption processes.

One of the biggest drawbacks of solid physisorbents for CO2 is their poor performance at high temperatures. This is due to their relatively low heat of CO2 sorption, which drives the adsorption/desorption equilibrium to favor desorption at above ambient temperatures. We show here that Hybrid Ultramicroporous Materials (HUMs), comprised of metals coordinated to organic ligands, and inorganic pillars, are highly effective physisorbents for capture CO2 in particular at very low partial pressure and even at moderate temperatures. We fine-tuned the HUM structure using various inorganic pillars and metal centers and produced a HUM NbOFFIVE-1-Cu that can effectively physisorb CO2 at 100 °C with CO2 uptake capacity comparable to at that 30 °C. NbOFFIVE-1-Cu is also highly stable even after 45 sorption cycles with no change in its CO2 capture properties.

Sulfur hexafluoride (SF6) is a highly potent greenhouse gas (GHG) that is mainly emitted from high-voltage electrical applications. The global warming potential (GWP) of the gas is almost 23 000 times that of CO2 and therefore, controlling its emission and recovery is of great importance from both an environmental and economic perspective. Solid adsorbents and adsorption-based technology is a cost-effective and energy-efficient pathway to recapture SF6 from its sources, which usually consist of dilute SF6 in N2. Here, we present a group of four highly porous and robust gallium- or vanadium-based metal–organic frameworks (MOFs) with exceptional SF6 uptake and selectivity. In particular, the novel gallium 1,2,4,5-tetrakis(4-carboxlatephenyl)benzene (TCPB4−) MOF (Ga-TBAPy) possesses 1-dimensional channels of suitable size (5.2 × 8.4 Å and 5.3 × 10 Å) to adsorb up to 2.25 mmol g−1 of SF6 at 10 kPa with an excellent SF6-over-N2 selectivity of 418. Ga-TCPB also exhibits high chemical stability in aqueous and acidic media as well as in organic solvents. 3D electron diffraction (3D ED) patterns combined with high-resolution electron microscopy images were employed to investigate the structure of these water-stable and cyclable MOF SF6 adsorbents. Furthermore, this study demonstrates the possibility of using these highly stable MOFs to capture SF6 from a gas mixture as well as how MOFs can offer an alternative and efficient way to mitigate the global warming contributions from the emission of SF6.

Bismuth-based metal-organic frameworks (Bi-MOFs) such as bismuth subgallate are important for applications ranging from medicine to gas separation and catalysis. Due to the porous nature of such Bi-MOFs, it would be valuable to understand their gas sorption and separation properties. Here, we present the gas sorption properties of three microporous Bi-MOFs, namely, CAU-17, CAU-33, and SU-101, along with a new trimesate-based structure, UU-200. We perform a detailed analysis of the sorption properties and kinetics of these Bi-MOFs. UU-200 shows good uptake capacities for CO2 (45.81 cm3 g−1 STP) and SF6 (24.69 cm3 g−1 STP) with CO2/N2 and SF6/N2 selectivities over 35 and 44, respectively at 293 K, 100 kPa. The structure of UU-200 is investigated using continuous rotation electron diffraction and is found to be a 3D porous framework containing pores with a diameter of 3.4–3.5 Å. Bi-MOFs as a group of relatively under-investigated types of MOFs have interesting sorption properties that render them promising for greenhouse gas adsorbents with good gas uptake capacities and high selectivities.

A metal-organic framework (MOF)CTH-17based on lanthanum-(III) and the conformationally chiral linker 1,2,3,4,5,6-hexakis(4-carboxyphenyl)-benzene, cpb6-: [La2(cpb)]middot1.5dmf was prepared by the solvothermal method indimethylformamide (dmf) and characterized by variable-temperature X-raypowder diffraction (VTPXRD), variable-temperature X-ray single-crystal diffrac-tion (SCXRD), and thermogravimetric analysis (TGA).CTH-17is a rod-MOFwith new topologyoch. It has high-temperature stability with Sohncke spacegroupsP6122/P6522 at 90 K andP622 at 300 and 500 K, all phases characterizedwith SCXRD and at 293 K also with three-dimensional (3D) electron diffraction. VTPXRD indicates a third phase appearing after620 K and stable up to 770 K. Gas sorption isotherms with N2indicate a modest surface area of 231 m2g-1forCTH-17, roughly inagreement with the crystal structure. Carbon dioxide sorption reveals a gate-opening effect ofCTH-17where the structure opens upwhen the loading of CO2reaches approximately similar to 0.45 mmol g-1or 1 molecule per unit cell. Based on the SCXRD data, this isinterpreted asflexibility based on the concerted movements of the propeller-like hexatopic cpb linkers, the movementintramolecularly transmitted by the pi-pi stacking of the cpb linkers and helped by thefluidity of the LaO6coordination sphere. Thiswas corroborated by density functional theory (DFT) calculations yielding the chiral phase (P622) as the energy minimum and acompletely racemic phase (P6/mmm), with symmetric cpb linkers representing a saddle point in a racemization process

An attractive approach to increase the aqueous apparent solubility of poorly soluble drugs is to formulate them in their amorphous state. In the present study, celecoxib, a poorly soluble drug, was successfully loaded into mesoporous magnesium carbonate (MMC) in its amorphous state via a solvent evaporation method. Crystallization of celecoxib was suppressed, and no reaction with the carrier was detected. The MMC formulation was evaluated in vitro and in vivo in terms of oral bioavailability. Celebra®, a commercially available formulation, was used as a reference. The two celecoxib formulations were orally administrated in male rats (average of n = 6 animals per group), and blood samples for plasma were taken from all animals at different time points after administration. There was no statistical difference (p > 0.05) in AUCinf between the two formulations. The results showed that MMC may be a promising drug delivery excipient for increasing the bioavailability of compounds with solubility-limited absorption.