Nanofiber Systems as Herbal Bioactive Compounds Carriers: Current Applications in Healthcare

Nanofibers have emerged as a potential novel platform due to their physicochemical properties for healthcare applications. Nanofibers’ advantages rely on their high specific surface-area-to-volume and highly porous mesh. Their peculiar assembly allows cell accommodation, nutrient infiltration, gas exchange, waste excretion, high drug release rate, and stable structure. This review provided comprehensive information on the design and development of natural-based polymer nanofibers with the incorporation of herbal medicines for the treatment of common diseases and their in vivo studies. Natural and synthetic polymers have been widely used for the fabrication of nanofibers capable of mimicking extracellular matrix structure. Among them, natural polymers are preferred because of their biocompatibility, biodegradability, and similarity with extracellular matrix proteins. Herbal bioactive compounds from natural extracts have raised special interest due to their prominent beneficial properties in healthcare. Nanofiber properties allow these systems to serve as bioactive compound carriers to generate functional matrices with antimicrobial, anti-inflammatory, antioxidant, antiseptic, anti-viral, and other properties which have been studied in vitro and in vivo, mostly to prove their wound healing capacity and anti-inflammation properties.

Quantitative Investigation of the Morphologically Corrugated CVD-grown Graphene Monolayer Surface with a Nanoparticle-on-Mirror system

Graphene can be used as a starting material for the synthesis of useful nano-complexes for flexible, transparent electrodes, therapeutic, bio-diagnostics and bio-sensing. In order to apply graphene in the medical field, chemical vapor deposition (CVD) method has been mainly utilized considering its large and near-homogenious carbon constituents. Especially, the less degree of perturbation of graphene monolayer (GM), which is followed by the underneath catalytic Cu surface morphology, is very crucial in terms of providing the suspended GM and relatively fluent lateral carrier mobility with lower sheet resistance value. In this work, we can suggest a surface-Enhanced Raman Spectroscopic (SERS) indicator in a quantitative way on the status of z-directional morphological corrugation of a CVD–grown GM (CVD-GM) by applying a Nanoparticle-on-Mirror (NPoM) system composed of Au nanoparticle (NP) / CVD-GM / Au thin film (TF) plasmonic junction structure. A new (or enhanced) Radial Breathing Like Mode (RBLM) SERS signal around ~150 cm-1 from CVD-GM spaced in NPoM is clearly observed by employing a local z-polarized incident field formed at the Au NP–Au TF plasmonic gap junctions. With this observation, the value of I[out-of-plane, RBLM] / I[in-plane, [2D] at certain domains, it can be suggested as a new optical nano-metrology value to relatively determine between lower z-directional morphological corrugation (or protrusion) status of a CVD-GM spaced in our NPoM system (lower I[RBLM] / I[2D] value) and higher degree of lateral carrier mobility of the CVD-GM associated with lower sheet resistance values as a result of higher blue-shifted Raman in-plane (G, 2D) peak maximum position. Furthermore, we will also expect the bio-sensing performances by utilizing the high specific surface area and ultrahigh flexibility of the CVD-GM in one of the future prospective works such as pressure-strain, strain-to-electricity and chemical-coupled sensor via I[RBLM] / I[2D] values.

Composite Bioinks With Mesoporous Bioactive Glasses—A Critical Evaluation of Results Obtained by In Vitro Experiments

Besides osteoconductivity and a high degradation rate, mesoporous bioactive glasses (MBGs) are specific for their highly ordered channel structure and high specific surface area, making them suitable as drug and/or growth factor delivery systems. On the other hand, the mesoporous channel structure and MBG composition can have an effect on common cell evaluation assays, leading to inconclusive results. This effect is especially important when MBG is mixed in composite bioinks, together with cells. Additionally, the hydrogel component of the ink can influence the degradation of MBG, leading to different ion releases, which can additionally affect the analyses. Hence, our aim here was to show how the MBG structure and composition influence common cell viability and differentiation assays when calcium (Ca)- or magnesium (Mg)-containing glass is part of an alginate-based composite bioink. We suggested pre-labeling of cells with DiI prior to bioprinting and staining with calcein-AM to allow identification of metabolically active cells expressing signals in both green and red channels, allowing the use of fluorescence imaging for cell viability evaluations in the presence of high amounts (7 wt %) of MBGs. The release and uptake of ions during degradation of CaMBG and MgMBG were significantly changed by alginate in the composite bioinks, as confirmed by higher release and uptake from bulk glasses. Additionally, we detected a burst release of Mg2+ from composites only after 24 h of incubation. Furthermore, we demonstrated that released ions and the mesoporous channel structure affect the measurement of lactate dehydrogenase (LDH) and alkaline phosphatase activity (ALP) in bioprinted composite scaffolds. Measured LDH activity was significantly decreased in the presence of CaMBG. On the other hand, the presence of MgMBG induced increased signal measured for the ALP. Taken together, our findings show how composite bioinks containing MBGs can interfere with common analyses, obtaining misleading results.

Sustainable Applications of Nanofibers in Agriculture and Water Treatment: A Review

Natural fibers are an important source for producing polymers, which are highly applicable in their nanoform and could be used in very broad fields such as filtration for water/wastewater treatment, biomedicine, food packaging, harvesting, and storage of energy due to their high specific surface area. These natural nanofibers could be mainly produced through plants, animals, and minerals, as well as produced from agricultural wastes. For strengthening these natural fibers, they may reinforce with some substances such as nanomaterials. Natural or biofiber-reinforced bio-composites and nano–bio-composites are considered better than conventional composites. The sustainable application of nanofibers in agricultural sectors is a promising approach and may involve plant protection and its growth through encapsulating many bio-active molecules or agrochemicals (i.e., pesticides, phytohormones, and fertilizers) for smart delivery at the targeted sites. The food industry and processing also are very important applicable fields of nanofibers, particularly food packaging, which may include using nanofibers for active–intelligent food packaging, and food freshness indicators. The removal of pollutants from soil, water, and air is an urgent field for nanofibers due to their high efficiency. Many new approaches or applicable agro-fields for nanofibers are expected in the future, such as using nanofibers as the indicators for CO and NH3. The role of nanofibers in the global fighting against COVID-19 may represent a crucial solution, particularly in producing face masks.

Analysis of the Factors Affecting the Instrumentation of the Technological Process of the Activated Carbon Material Production

The article discusses significance of the development of activated carbon materials with a high specific surface area and high porosity. The features of the course of chemical activation and the factors influencing the characteristics of the obtained material have been established. The main stages of the activation of the carbon material, including the preliminary raw carbon material carbonization, its alkaline activation, and the post-processing of the created material, have been determined. The mutual influence of temperature and flow rate of an inert gas on the characteristics of a carbon material obtained with a BET specific surface in the range of 2550–2700 m2/g is experimentally investigated. The analysis of the obtained results has been carried out. Recommendations are given for reducing ambiguity and uncertainty during the transition from laboratory research to pilot production. The resulting activated carbon material can be used as a sorbent in gas purification systems, gas accumulators and for solving various environmental problems.

Metal–organic frameworks (MOFs) based nanofiber architectures for the removal of heavy metal ions

Metal–organic frameworks (MOFs) are promising and effective materials for removing heavy metal ions from contaminated water owing to their high porosity, remarkable physical and chemical properties, and high specific surface area.

Synthesis of composite nanostructure natural ZrO2 and magnetite particles (Fe3O4@ZrO2) and study of its lead ion adsorption efficiency

The potential of zircon minerals in Indonesia, especially in Central Kalimantan, has not been adequately explored and developed into valuable materials with high technical and economic value and environmentally friendly. This research has the potential to be processed and formed into advanced materials, seeing its high potential as an excellent adsorbent for anions/cations in water treatment and industrial wastewater. This research aims to develop raw zircon minerals into zircon oxides, which will later be composited with magnetic nanoparticles. The zircon mineral processing is carried out using hydrothermal methods. It is known that the physical and mechanical characteristics are suitable to be developed by having good reusability and durability as advanced materials. The adsorbent characterizations of FTIR, SEM, and XRF analysis showed that the Fe3O4@ZrO2 had many different functional groups and a high specific surface area for adsorption processes. The Fe3O4@ZrO2 showed high adsorption uptake capacity and selectivity for the lead in the Sasirangan textiles wastewater. Therefore, the Fe3O4@ZrO2 have the potential to be used as an adsorbent in water and wastewater treatment.

Preparation and Characterization of Gaphene-Doped Carbon-Aerogel Electrode

Carbon-aerogel is a kind of nano-porous carbon material with special three-dimensional network structure. Electrode materials with high specific surface area, high porosity, superior conductivity and low density were obtained by adding graphene to prepare graphene-doped carbon-aerogels.

Waste-honeycomb-derived in situ N-doped Hierarchical porous carbon as sulfur host in lithium–sulfur battery

Waste honeycomb derived porous carbon with a high specific surface area of 1683.6 m2 g−1 are prepared via a facile simultaneous activation/carbonization. The corresponding porous carbon/sulfur composite cathode exhibits a durable stable performance up to 500 cycles at 1 C.