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Small (Weinheim An Der Bergstrasse,... Mar 2023Understanding the direct interaction of nanostructures per se with biological systems is important for biomedical applications. However, whether nanostructures regulate...
Understanding the direct interaction of nanostructures per se with biological systems is important for biomedical applications. However, whether nanostructures regulate biological systems by targeting specific cellular proteins remains largely unknown. In the present work, self-assembling nanomicelles are constructed using small-molecule oleanolic acid (OA) as a molecular template. Unexpectedly, without modifications by functional ligands, OA nanomicelles significantly activate cellular proteasome function by directly binding to 20S proteasome subunit alpha 6 (PSMA6). Mechanism study reveals that OA nanomicelles interact with PSMA6 to dynamically modulate its N-terminal domain conformation change, thereby controlling the entry of proteins into 20S proteasome. Subsequently, OA nanomicelles accelerate the degradation of several crucial proteins, thus potently driving cancer cell pyroptosis. For translational medicine, OA nanomicelles exhibit a significant anticancer potential in tumor-bearing mouse models and stimulate immune cell infiltration. Collectively, this proof-of-concept study advances the mechanical understanding of nanostructure-guided biological effects via their inherent capacity to activate proteasome.
Topics: Animals; Mice; Proteasome Endopeptidase Complex; Pyroptosis; Cytoplasm; Micelles; Nanostructures; Neoplasms
PubMed: 36549896
DOI: 10.1002/smll.202205531 -
Small (Weinheim An Der Bergstrasse,... Jul 2021Electrochemical microscopy techniques have extended the understanding of surface chemistry to the micrometer and even sub-micrometer level. However, fundamental...
Electrochemical microscopy techniques have extended the understanding of surface chemistry to the micrometer and even sub-micrometer level. However, fundamental questions related to charge transport at the solid-electrolyte interface, such as catalytic reactions or operation of individual ion channels, require improved spatial resolutions down to the nanoscale. A prerequisite for single-molecule electrochemical sensitivity is the reliable detection of a few electrons per second, that is, currents in the atto-Ampere (10 A) range, 1000 times below today's electrochemical microscopes. This work reports local cyclic voltammetry (CV) measurements at the solid-liquid interface on ferrocene self-assembled monolayer (SAM) with sub-atto-Ampere sensitivity and simultaneous spatial resolution < 80 nm. Such sensitivity is obtained through measurements of the charging of the local faradaic interface capacitance at GHz frequencies. Nanometer-scale details of different molecular organizations with a 19% packing density difference are resolved, with an extremely small dispersion of the molecular electrical properties. This is predicted previously based on weak electrostatic interactions between neighboring redox molecules in a SAM configuration. These results open new perspectives for nano-electrochemistry like the study of quantum mechanical resonance in complex molecules and a wide range of applications from electrochemical catalysis to biophysics.
Topics: Electric Capacitance; Electrochemistry; Electrons; Nanotechnology; Oxidation-Reduction
PubMed: 34121314
DOI: 10.1002/smll.202101253 -
Small (Weinheim An Der Bergstrasse,... Aug 2022Spintronics and molecular chemistry have achieved remarkable achievements separately. Their combination can apply the superiority of molecular diversity to intervene or... (Review)
Review
Spintronics and molecular chemistry have achieved remarkable achievements separately. Their combination can apply the superiority of molecular diversity to intervene or manipulate the spin-related properties. It inevitably brings in a new type of functional devices with a molecular interface, which has become an emerging field in information storage and processing. Normally, spin polarization has to be realized by magnetic materials as manipulated by magnetic fields. Recently, chiral-induced spin selectivity (CISS) was discovered surprisingly that non-magnetic chiral molecules can generate spin polarization through their structural chirality. Here, the recent progress of integrating the strengths of molecular chemistry and spintronics is reviewed by introducing the experimental results, theoretical models, and device performances of the CISS effect. Compared to normal ferromagnetic metals, CISS originating from a chiral structure has great advantages of high spin polarization, excellent interface, simple preparation process, and low cost. It has the potential to obtain high efficiency of spin injection into metals and semiconductors, getting rid of magnetic fields and ferromagnetic electrodes. The physical mechanisms, unique advantages, and device performances of CISS are sequentially clarified, revealing important issues to current scientific research and industrial applications. This mini-review points out a key technology of information storage for future spintronic devices without magnetic components.
Topics: Electrodes; Magnetic Fields; Magnets; Stereoisomerism
PubMed: 35836101
DOI: 10.1002/smll.202203015 -
Small (Weinheim An Der Bergstrasse,... Feb 2020The theoretical analysis and experimental demonstration of a new concept are presented for a non-contact scanning probe, in which transport of fluid and molecules is...
The theoretical analysis and experimental demonstration of a new concept are presented for a non-contact scanning probe, in which transport of fluid and molecules is controlled by electric fields. The electrokinetic scanning probe (ESP) enables local chemical and biochemical interactions with surfaces in liquid environments. The physical mechanism and design criteria for such a probe are presented, and its compatibility with a wide range of processing solutions and pH values are demonstrated. The applicability of the probe is shown for surface patterning in conjunction with localized heating and 250-fold analyte stacking.
Topics: Chemistry Techniques, Analytical; Electrochemical Techniques; Hydrogen-Ion Concentration; Solutions
PubMed: 31885215
DOI: 10.1002/smll.201904268 -
Small (Weinheim An Der Bergstrasse,... Jan 2023Active layer material plays a critical role in promoting the performance of an organic solar cell (OSC). Small-molecule (SM) materials have the merits of well-defined... (Review)
Review
Active layer material plays a critical role in promoting the performance of an organic solar cell (OSC). Small-molecule (SM) materials have the merits of well-defined chemical structures, few batch-to-batch variations, facile synthesis and purification procedures, and easily tuned properties. SM-donor and non-fullerene acceptor (NFA) innovations have recently produced all-small-molecule (ASM) devices with power conversion efficiencies that exceed 17% and approach those of their polymer-based counterparts, thereby demonstrating their great future commercialization potential. In this review, recent progress in both SM donors and NFAs to illustrate structure-property relationships and various morphology-regulation strategies are summarized. Finally, ASM-OSC challenges and outlook are discussed.
Topics: Polymers
PubMed: 36449633
DOI: 10.1002/smll.202205594 -
Small (Weinheim An Der Bergstrasse,... Aug 2021Photodynamic therapy (PDT) has shown great potential for tumor treatment with merits of non-invasiveness, high selectivity, and minimal side effects. However,... (Review)
Review
Photodynamic therapy (PDT) has shown great potential for tumor treatment with merits of non-invasiveness, high selectivity, and minimal side effects. However, conventional type II PDT relying on O presents poor therapeutic efficacy for hypoxic tumors due to the oxygen-dependent manner. Alternatively, emerging researches have demonstrated that type I PDT exhibits superiority over type II PDT in tumor treatment owing to its diminished oxygen-dependence. In this review, state-of-the-art studies concerning recent progress in type I photosensitizers are scrutinized, emphasizing the strategies to construct highly effective type I photosensitizers. As the foundation, basic principles of type I PDT are presented, and up-to-date type I photosensitizers are summarized and classified based on their attributes. Then, a literature review of representative type I photosensitizers (including nanomaterials and small molecules) is presented with impetus to delineate their novel designs, action mechanisms, as well as anticancer PDT applications. Finally, the remaining challenges and development directions of type I photosensitizers are outlined, highlighting key scientific issues toward clinical translations.
Topics: Humans; Nanostructures; Neoplasms; Photochemotherapy; Photosensitizing Agents
PubMed: 34038611
DOI: 10.1002/smll.202006742 -
Small (Weinheim An Der Bergstrasse,... May 2022Cancer diagnosis and therapeutics (theranostics) based on the tumor microenvironment (TME) and biomarkers has been an emerging approach for precision medicine. DNA... (Review)
Review
Cancer diagnosis and therapeutics (theranostics) based on the tumor microenvironment (TME) and biomarkers has been an emerging approach for precision medicine. DNA nanotechnology dynamically controls the self-assembly of DNA molecules at the nanometer scale to construct intelligent DNA chemical reaction systems. The DNA logic circuit is a particularly emerging approach for computing within the DNA chemical systems. DNA logic circuits can sensitively respond to tumor-specific markers and the TME through logic operations and signal amplification, to generate detectable signals or to release anti-cancer agents. In this review, the fundamental concepts of DNA logic circuits are clarified, the basic modules in the circuit are summarized, and how this advanced nano-assembly circuit responds to tumor-related molecules, how to perform logic operations, to realize signal amplification, and selectively release drugs through discussing over 30 application examples, are demonstrated. This review shows that DNA logic circuits have powerful logic judgment and signal amplification functions in improving the specificity and sensitivity of cancer diagnosis and making cancer treatment controllable. In the future, researchers are expected to overcome the existing shortcomings of DNA logic circuits and design smarter DNA devices with better biocompatibility and stability, which will further promote the development of cancer theranostics.
Topics: Computers, Molecular; DNA; Humans; Logic; Neoplasms; Precision Medicine; Tumor Microenvironment
PubMed: 35254723
DOI: 10.1002/smll.202108008 -
Small (Weinheim An Der Bergstrasse,... Aug 2021Water molecules confined to low-dimensional spaces exhibit unusual properties compared to bulk water. For example, the alternating hydrophilic and hydrophobic... (Review)
Review
Water molecules confined to low-dimensional spaces exhibit unusual properties compared to bulk water. For example, the alternating hydrophilic and hydrophobic nanodomains on flat silicon wafer can induce the abnormal spreading of water (contact angles near 0°) which is caused by the 2D capillary effect. Hence, exploring the physicochemical properties of confined water from the nanoscale is of great value for understanding the challenges in material science and promoting the applications of nanomaterials in the fields of mass transport, nanofluidic designing, and fuel cell. The knowledge framework of confined water can also help to better understand the complex functions of the hydration layer of biomolecules, and even trace the origin of life. In this review, the physical properties, abnormal behaviors, and functions of the confined water are mainly summarized through several common low-dimensional water formats in the fields of solid/air-water interface, nanochannel confinement, and biological hydration layer. These researches indicate that the unusual behaviors of the confined water depend strongly on the confinement size and the interaction between the molecules and confining surface. These diverse properties of confined water open a new door to materials science and may play an important role in the future development of biology.
Topics: Hydrophobic and Hydrophilic Interactions; Nanostructures; Water
PubMed: 34176214
DOI: 10.1002/smll.202100788 -
Small (Weinheim An Der Bergstrasse,... Dec 2022As a relatively new type of fluorescent carbon-based nanomaterials, multicolor carbon dots (MCDs) have attracted much attention because of their excellent... (Review)
Review
As a relatively new type of fluorescent carbon-based nanomaterials, multicolor carbon dots (MCDs) have attracted much attention because of their excellent biocompatibility, tunable photoluminescence (PL), high quantum yield, and unique electronic and physicochemical properties. The multicolor emission characteristics of carbon dots (CDs) obviously depend on the carbon source precursor, reaction conditions, and reaction environment, which directly or indirectly determines the multicolor emission characteristics of CDs. Therefore, this review is the first systematic classification and summary of multiple regulation methods of synthetic MCDs and reviews the recent research progress in the synthesis of MCDs from a variety of precursor materials such as aromatic molecules, small organic molecules, and natural biomass, focusing on how different regulation methods produce corresponding MCDs. This review also introduces the innovative applications of MCDs in the fields of biological imaging, light-emitting diodes (LEDs), sensing, and anti-counterfeiting due to their excellent PL properties. It is hoped that by selecting appropriate adjustment methods, this review can inspire and guide the future research on the design of tailored MCDs, and provide corresponding help for the development of multifunctional MCDs.
Topics: Carbon; Quantum Dots; Fluorescent Dyes; Biomass; Nanostructures
PubMed: 36328736
DOI: 10.1002/smll.202205099 -
Small (Weinheim An Der Bergstrasse,... Sep 2023Chirality is a universal phenomenon in molecular and biological systems, denoting an asymmetric configurational property where an object cannot be superimposed onto its... (Review)
Review
Chirality is a universal phenomenon in molecular and biological systems, denoting an asymmetric configurational property where an object cannot be superimposed onto its mirror image by any kind of translation or rotation, which is ubiquitous on the scale from neutrinos to spiral galaxies. Chirality plays a very important role in the life system. Many biological molecules in the life body show chirality, such as the "codebook" of the earth's biological diversity-DNA, nucleic acid, etc. Intriguingly, living organisms hierarchically consist of homochiral building blocks, for example, l-amino acids and d-sugars with unknown reason. When molecules with chirality interact with these chiral factors, only one conformation favors the positive development of life, that is, the chiral host environment can only selectively interact with chiral molecules of one of the conformations. The differences in chiral interactions are often manifested by chiral recognition, mutual matching, and interactions with chiral molecules, which means that the stereoselectivity of chiral molecules can produce changes in pharmacodynamics and pathology. Here, the latest investigations are summarized including the construction and applications of chiral materials based on natural small molecules as chiral source, natural biomacromolecules as chiral sources, and the material synthesized by design as a chiral source.
PubMed: 37217989
DOI: 10.1002/smll.202303059