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Small (Weinheim An Der Bergstrasse,... Sep 20224D bioprinting techniques that facilitate formation of shape-changing scaffold-free cell condensates with prescribed geometries have yet been demonstrated. Here, a...
4D bioprinting techniques that facilitate formation of shape-changing scaffold-free cell condensates with prescribed geometries have yet been demonstrated. Here, a simple 4D bioprinting approach is presented that enables formation of a shape-morphing cell condensate-laden bilayer system. The strategy produces scaffold-free cell condensates which morph over time into predefined complex shapes. Cell condensate-laden bilayers with specific geometries are readily fabricated by bioprinting technologies. The bilayers have tunable deformability and microgel (MG) degradation, enabling controllable morphological transformations and on-demand liberation of deformed cell condensates. With this system, large cell condensate-laden constructs with various complex shapes are obtained. As a proof-of-concept study, the formation of the letter "C"- and helix-shaped robust cartilage-like tissues differentiated from human mesenchymal stem cells (hMSCs) is demonstrated. This system brings about a versatile 4D bioprinting platform idea that is anticipated to broaden and facilitate the applications of cell condensation-based 4D bioprinting.
Topics: Bioprinting; Cartilage; Cell Differentiation; Humans; Hydrogels; Microgels; Printing, Three-Dimensional; Tissue Engineering; Tissue Scaffolds
PubMed: 35973946
DOI: 10.1002/smll.202202196 -
Small (Weinheim An Der Bergstrasse,... May 2022The origin of life is still one of humankind's great mysteries. At the transition between nonliving and living matter, protocells, initially featureless aggregates of... (Review)
Review
The origin of life is still one of humankind's great mysteries. At the transition between nonliving and living matter, protocells, initially featureless aggregates of abiotic matter, gain the structure and functions necessary to fulfill the criteria of life. Research addressing protocells as a central element in this transition is diverse and increasingly interdisciplinary. The authors review current protocell concepts and research directions, address milestones, challenges and existing hypotheses in the context of conditions on the early Earth, and provide a concise overview of current protocell research methods.
Topics: Artificial Cells
PubMed: 35322554
DOI: 10.1002/smll.202106624 -
Small (Weinheim An Der Bergstrasse,... Sep 2019In this Review, an effort is made to discuss the most recent progress and future trend in the two-way traffic of the interactions between plants and nanoparticles (NPs).... (Review)
Review
In this Review, an effort is made to discuss the most recent progress and future trend in the two-way traffic of the interactions between plants and nanoparticles (NPs). One way is the use of plants to synthesize NPs in an environmentally benign manner with a focus on the mechanism and optimization of the synthesis. Another way is the effects of synthetic NPs on plant fate with a focus on the transport mechanisms of NPs within plants as well as NP-mediated seed germination and plant development. When NPs are in soil, they can be adsorbed at the root surface, followed by their uptake and inter/intracellular movement in the plant tissues. NPs may also be taken up by foliage under aerial deposition, largely through stomata, trichomes, and cuticles, but the exact mode of NP entry into plants is not well documented. The NP-plant interactions may lead to inhibitory or stimulatory effects on seed germination and plant development, depending on NP compositions, concentrations, and plant species. In numerous cases, radiation-absorbing efficiency, CO assimilation capacity, and delay of chloroplast aging have been reported in the plant response to NP treatments, although the mechanisms involved in these processes remain to be studied.
Topics: Nanoparticles; Plant Roots; Plants
PubMed: 31318142
DOI: 10.1002/smll.201901794 -
Small (Weinheim An Der Bergstrasse,... Apr 2018Contact lens is a ubiquitous technology used for vision correction and cosmetics. Sensing in contact lenses has emerged as a potential platform for minimally invasive...
Contact lens is a ubiquitous technology used for vision correction and cosmetics. Sensing in contact lenses has emerged as a potential platform for minimally invasive point-of-care diagnostics. Here, a microlithography method is developed to fabricate microconcavities and microchannels in a hydrogel-based contact lens via a combination of laser patterning and embedded templating. Optical microlithography parameters influencing the formation of microconcavities including ablation power (4.3 W) and beam speed (50 mm s ) are optimized to control the microconcavity depth (100 µm) and diameter (1.5 mm). The fiber templating method allows the production of microchannels having a diameter range of 100-150 µm. Leak-proof microchannel and microconcavity connections in contact lenses are validated through flow testing of artificial tear containing fluorescent microbeads (Ø = 1-2 µm). The microconcavities of contact lenses are functionalized with multiplexed fluorophores (2 µL) to demonstrate optical excitation and emission capability within the visible spectrum. The fabricated microfluidic contact lenses may have applications in ophthalmic monitoring of metabolic disorders at point-of-care settings and controlled drug release for therapeutics.
Topics: Contact Lenses; Microfluidics; Photography
PubMed: 29521022
DOI: 10.1002/smll.201704363 -
Small (Weinheim An Der Bergstrasse,... Jan 2021High-sensitivity detection of minute quantities or concentration variations of analytes of clinical importance is critical for biosensing to ensure accurate disease... (Review)
Review
High-sensitivity detection of minute quantities or concentration variations of analytes of clinical importance is critical for biosensing to ensure accurate disease diagnostics and reliable health monitoring. A variety of sensitivity-improving concepts have been proposed from chemical, physical, and biological perspectives. In this review, elements that are responsible for sensitivity enhancement are classified and discussed in accordance with their operating steps in a typical biosensing workflow that runs through sampling, analyte recognition, and signal transduction. With a focus on optical biosensing, exemplary sensitivity-improving strategies are introduced, which can be developed into "plug-and-play" modules for many current and future sensors, and discuss their mechanisms to enhance biosensing performance. Three major strategies are covered: i) amplification of signal transduction by polymerization and nanocatalysts, ii) diffusion-limit-breaking systems for enhancing sensor-analyte contact and subsequent analyte recognition by fluid-mixing and analyte-concentrating, and iii) combined approaches that utilize renal concentration at the sampling and recognition steps and chemical signal amplification at the signal transduction step.
Topics: Biosensing Techniques; Polymerization
PubMed: 33369864
DOI: 10.1002/smll.202004988 -
Small (Weinheim An Der Bergstrasse,... May 2015Aptamers are composed of short RNA or single-stranded DNA sequences that, when folded into their unique 3D conformation, can bind to their targets with high specificity... (Review)
Review
Aptamers are composed of short RNA or single-stranded DNA sequences that, when folded into their unique 3D conformation, can bind to their targets with high specificity and affinity. Although functionally similar to protein antibodies, oligonucleotide aptamers offer several advantages over protein antibodies in biomedical and clinical applications. Through the enhanced permeability and retention effect, nanomedicines can improve the therapeutic index of a treatment and reduce side effects by enhancing accumulation at the disease site. However, this targets tumors passively and, thus, may not be ideal for targeted therapy. To construct ligand-directed "active targeting" nanobased delivery systems, aptamer-equipped nanomedicines have been tested for in vitro diagnosis, in vivo imaging, targeted cancer therapy, theranostic approaches, sub-cellular molecule detection, food safety, and environmental monitoring. This review focuses on the development of aptamer-conjugated nanomedicines and their application for in vivo imaging, targeted therapy, and theranostics.
Topics: Aptamers, Nucleotide; Drug Delivery Systems; Humans; Nanomedicine; Theranostic Nanomedicine
PubMed: 25677591
DOI: 10.1002/smll.201403073 -
Small (Weinheim An Der Bergstrasse,... Mar 2022Reversible electrochemical intercalation of cations into the interlayer space of 2D materials induces tunable physical and chemical properties in them. In MXenes, a...
Reversible electrochemical intercalation of cations into the interlayer space of 2D materials induces tunable physical and chemical properties in them. In MXenes, a large class of recently developed 2D carbides and nitrides, low intercalation energy, high storage capacitance, and reversible intercalation of various cations have led to their improved performance in sensing and energy storage applications. Herein, a coupled nanopore-actuator system where an ultrathin free-standing MXene film serves as a nanopore support membrane and ionically active actuator is reported. In this system, the contactless MXene membrane in the electric field affects the cation movement in the field through their (de)intercalation between individual MXene flakes. This results in reversible swelling and contraction of the membrane monitored by ionic conductance through the nanopore. This unique nanopore coupled to a mechanical actuation system could provide new insights into designing single-molecule biosensing platforms at the nanoscale.
Topics: Cations; Electric Capacitance; Electricity; Nanopores
PubMed: 35297185
DOI: 10.1002/smll.202105857 -
Small (Weinheim An Der Bergstrasse,... Mar 2022Magnetic nanoparticles (MNPs) have various applications in biomedicine, including imaging, drug delivery and release, genetic modification, cell guidance, and... (Review)
Review
Magnetic nanoparticles (MNPs) have various applications in biomedicine, including imaging, drug delivery and release, genetic modification, cell guidance, and patterning. By combining MNPs with polymers, magnetic nanocomposites (MNCs) with diverse morphologies (core-shell particles, matrix-dispersed particles, microspheres, etc.) can be generated. These MNCs retain the ability of MNPs to be controlled remotely using external magnetic fields. While the effects of these biomaterials on the cell biology are still poorly understood, such information can help the biophysical modulation of various cellular functions, including proliferation, adhesion, and differentiation. After recalling the basic properties of MNPs and polymers, and describing their coassembly into nanocomposites, this review focuses on how polymeric MNCs can be used in several ways to affect cell behavior. A special emphasis is given to 3D cell culture models and transplantable grafts, which are used for regenerative medicine, underlining the impact of MNCs in regulating stem cell differentiation and engineering living tissues. Recent advances in the use of MNCs for tissue regeneration are critically discussed, particularly with regard to their prospective involvement in human therapy and in the construction of advanced functional materials such as magnetically operated biomedical robots.
Topics: Drug Delivery Systems; Humans; Magnetic Fields; Magnetics; Nanocomposites; Prospective Studies
PubMed: 34741417
DOI: 10.1002/smll.202104079 -
Small (Weinheim An Der Bergstrasse,... Jan 2021Cells are complex machines whose behaviors arise from their internal collection of dynamically interacting organelles, supramolecular complexes, and cytoplasmic... (Review)
Review
Cells are complex machines whose behaviors arise from their internal collection of dynamically interacting organelles, supramolecular complexes, and cytoplasmic chemicals. The current understanding of the nature by which subcellular biology produces cell-level behaviors is limited by the technological hurdle of measuring the large number (>10 ) of small-sized (<1 μm) heterogeneous organelles and subcellular structures found within each cell. In this review, the emergence of a suite of micro- and nano-technologies for studying intracellular biology on the scale of organelles is described. Devices that use microfluidic and microelectronic components for 1) extracting and isolating subcellular structures from cells and lysate; 2) analyzing the physiology of individual organelles; and 3) recreating subcellular assembly and functions in vitro, are described. The authors envision that the continued development of single organelle technologies and analyses will serve as a foundation for organelle systems biology and will allow new insight into fundamental and clinically relevant biological questions.
Topics: Biology; Microfluidics; Organelles
PubMed: 33345457
DOI: 10.1002/smll.202005793 -
Small (Weinheim An Der Bergstrasse,... Sep 2016The increasing miniaturization and resolution of image sensors bring challenges to conventional optical elements such as spectral filters and polarizers, the properties... (Review)
Review
The increasing miniaturization and resolution of image sensors bring challenges to conventional optical elements such as spectral filters and polarizers, the properties of which are determined mainly by the materials used, including dye polymers. Recent developments in spectral filtering and optical manipulating techniques based on nanophotonics have opened up the possibility of an alternative method to control light spectrally and spatially. By integrating these technologies into image sensors, it will become possible to achieve high compactness, improved process compatibility, robust stability and tunable functionality. In this Review, recent representative achievements on nanophotonic image sensors are presented and analyzed including image sensors with nanophotonic color filters and polarizers, metamaterial-based THz image sensors, filter-free nanowire image sensors and nanostructured-based multispectral image sensors. This novel combination of cutting edge photonics research and well-developed commercial products may not only lead to an important application of nanophotonics but also offer great potential for next generation image sensors beyond Moore's Law expectations.
Topics: Color; Imaging, Three-Dimensional; Nanostructures; Optics and Photonics; Semiconductors
PubMed: 27239941
DOI: 10.1002/smll.201600528