First Principles Calculations Study of Lithium-Montmorillonite for Humidity Sensor Application

In this study, we performed calculations on the water molecule adsorbed on lithium montmorillonite using first principles-calculation by means of electronic-structure calculation, with emphasis on approaches based on Density Functional Theory (DFT). The mechanism of water molecule adsorption on the surface of lithium-montmorillonite was investigated from the electronic structure point of view to seek the possibility of using montmorillonite as humidity sensor. The effects of the Van der Waals force to the electronic properties of water molecule on the surface of montmorillonite was also considered and obtained that the structure is more stable energetically. The interaction of water molecule with surface of montmorillonite yields the rotation of the hydrogen atoms of water molecule due to the occurrence of repulsive interaction between two positive ions of hydrogen of water molecule and lithium. From the calculations, lithium-montmorillonite can be considered as a good material for humidity sensor application since there is an electrical change observed even though it is a relatively small that is 0.657 eV

The Properties of Exosomes Derived from Mesenchymal Stem Cells Preconditioned with L-Ascorbic Acid and Cobalt (II) Chloride

Extracellular vesicles including exosomes, are produced by cells for intracellular communication. Preconditioning of parental cells influences exosome properties. The purpose of this study was to examine the effects of L-ascorbic acid (LAA) and cobalt (II) chloride (CoCl2) on human Wharton’s jelly mesenchymal stem cell (hWJ-MSC)-derived exosomes and their ability to promote stem cell differentiation into chondrocytes. The cells were isolated from the umbilical cord and characterized according to the criteria for mesenchymal stem cell.  The cells were cultured in a serum-free medium containing LAA and CoCl2. Cell-produced exosomes were isolated and characterized. hWJ-MSCs can grow in serum-free medium containing LAA and CoCl2. Exosomes derived from hWJ-MSCs had a round morphology, particle size within the exosome range, CD 63 expression, and the capacity to be internalized by cells. The production of exosomes by hWJ-MSCs was enhanced by LAA treatment. LAA and CoCl2 promoted stem cell differentiation into chondrocytes, as indicated by the production of collagen type II and glycosaminoglycans. LAA and CoCl2 affect the properties of MSC-derived exosomes. LAA induces cells to produce exosomes in greater quantities, which have the potential to promote chondrogenic differentiation of stem cells

Isolation of Native Plant-Derived Exosome-like Nanoparticles and Their Uptake by Human Cells

The exosome is a nano-sized vesicular particle commonly secreted from eukaryotic cells to extracellular space. Exosome functions in cellular communication, nutrients or bioactive compounds delivery, and cellular immunity. It is believed that plant-derived exosome-like particle (PDEN) potential to deliver nano-bioactive compounds to the human body. As Indonesia is one of the herbal centers of the world, we are encouraged to develop natural richness for human welfare. The study aimed to verify various methods to isolate exosomes from the fresh ginger rhizome and quina cells and examine the ginger PDENs' capacity to internalize in vitro human cells. The PDENs isolation was carried out by centrifugation and precipitation. The particles were observed through a transmission electron microscope, dynamic light scattering, and particle size analysis. Differential ultracentrifugation combined with PEG6000 provided a better size range of particles. Nanoparticles tracking analysis performed the concentration of particles within a specific size range. Ginger and quina PDENs size ranged from 40-650 nm, and the concentration was 3.6 × 107 and 2.8 × 106, respectively. The PKH67-labelled ginger PDENs were taken up by human dermal fibroblast and human Wharton's jelly mesenchymal stem cells after 30 minutes and 21 hours. DPPH assays revealed that ginger PDENs have antioxidant activity, indicating the presence of some nano-molecules in those particles. This study would be the baseline for developing ginger PDENs as a functional food with nano-ingredients, or as an effective vehicle of nano-drug, for human health

Challenges and strategy in treatment with exosomes for cell-free-based tissue engineering in dentistry

In dentistry, problems of craniofacial, osteochondral, periodontal tissue, nerve, pulp or endodontics injuries, and osteoarthritis need regenerative therapy. The use of stem cells in dental tissue engineering pays a lot of increased attention, but there are challenges for its clinical applications. Therefore, cell-free-based tissue engineering using exosomes isolated from stem cells is regarded an alternative approach in regenerative dentistry. However, practical use of exosome is restricted by limited secretion capability of cells. For future regenerative treatment with exosomes, efficient strategies for large-scale clinical applications are being studied, including the use of ceramics-based scaffold to enhance exosome production and secretion which can resolve limited exosome secretory from the cells when compared with the existing methods available. Indeed, more research needs to be done on these strategies going forward

Absorption of lithium in montmorillonite: A density functional theory (DFT) study

The absorption of lithium in montmorillonite [LiSi8(Al 3Mg)O20(OH)4] was investigated using Density Functional Theory (DFT). The final position of lithium after absorption was found to be in good agreement with an experimental observation where lithium atom migrated from the interlayer into the vacant octahedral site of montmorillonite. The lithium absorbed on montmorillonite was held together by a very strong attraction between ions and exhibited an insulating behavior as depicted from the density of states curve. Due to the presence of lithium in the octahedral site of montmorillonite, the OH group reoriented itself perpendicular to the ab plane and an electron of lithium was transferred in order to compensate the existing net charge of montmorillonite caused by isomorphous substitutions. Relative small charge transfer was observed between lithium and montmorillonite. Copyright © 2011 American Scientific Publishers

Extracellular vesicles: a promising cell-free therapy for cartilage repair

Few effective therapies for cartilage repair have been found as cartilage has a low regenerative capacity. Extracellular vesicles (EVs), including exosomes, are produced by cells and contain bioactive components such as nucleic acids, proteins, lipids and other metabolites that have potential for treating cartilage injuries. Challenges like the difficulty in standardizing targeted therapy have prevented EVs from being used frequently as a treatment option. In this review we present current studies, mechanisms and delivery strategies of EVs. Additionally, we describe the challenges and future directions of EVs as therapeutic agents for cartilage repair

Plant-derived exosome-like nanoparticles: A concise review on its extraction methods, content, bioactivities, and potential as functional food ingredient

Plant-derived exosome-like nanoparticles (PDENs) are small vesicles released by multivesicular bodies mainly to communicate between cells and regulate immunity against pathogen attack. Current studies have reported that PDENs could modulate gene expression in a cross-kingdom fashion. Therefore, PDENs could be a potential future functional food ingredient as their cross-kingdom communication abilities were reported to exert multiple health benefits. Macrophage and other cells have been reported to absorb PDENs in a manner regulated by the membrane lipid and protein profile and the intactness of the PDENs lipid bilayer. PDENs could be extracted from plant materials by various techniques such as ultracentrifugation, immunoaffinity, size-based isolation, and precipitation, though each method has its pros and cons. PDENs mainly contain lipid, protein, and genetic materials, mainly micro RNAs, which could exert multiple health benefits and functionalities when consumed in sufficient amounts. However, most studies on the health functionalities of PDENs were conducted through in-vitro and in-vivo studies, and its potency to be used as a functional ingredient remains a question as PDENs are sensitive to storage and processing condition and requires costly extraction method. This concise review features various exosome extraction methods, contents of PDENs and their roles, the health functionalities of PDENs, and its potency as a functional food ingredient

Plant-Derived Exosome-like Nanoparticles for Biomedical Applications and Regenerative Therapy

Plant-derived exosome-like nanoparticles (PDENs) comprise various bioactive biomolecules. As an alternative cell-free therapeutic approach, they have the potential to deliver nano-bioactive compounds to the human body, and thus lead to various anti-inflammatory, antioxidant, and anti-tumor benefits. Moreover, it is known that Indonesia is one of the herbal centers of the world, with an abundance of unexplored sources of PDENs. This encouraged further research in biomedical science to develop natural richness in plants as a source for human welfare. This study aims to verify the potential of PDENs for biomedical purposes, especially for regenerative therapy applications, by collecting and analyzing data from the latest relevant research and developments