Uniform silver-containing metal nanostructures with strong and stable surface-enhanced Raman scattering (SERS) signals hold great promise for developing ultrasensitive probes for biodetection. Nevertheless, the direct synthesis of such ready-to-use nanoprobes remains extremely challenging. Herein we report a DNA-mediated gold–silver nanomushroom with interior nanogaps directly synthesized and used for multiplex and simultaneous SERS detection of various DNA and RNA targets. The DNA involved in the nanostructures can act as not only gap DNA (mediated DNA) but also probe DNA (hybridized DNA), and DNA’s involvement enables the nanostructures to have the inherent ability to recognize DNA and RNA targets. Importantly, we were the first to establish a new method for the generation of multicolor SERS probes using two different strategies. First Raman-labeled alkanethiol probe DNA was assembled on gold nanoparticles, and second, thiol-containing Raman reporters were coassembled with the probe DNA. The ready-to-use probes also give great potential to develop ultrasensitive detection methods for various biological molecules.

It is highly demanding to design active nanomotors that can move in response to specific signals with controllable rate and direction. A catalysis-driven nanomotor was constructed by designing catalytically and plasmonically active Janus gold nanoparticles (Au NPs), which generate an asymmetric temperature gradient of local solvent surrounding NPs in catalytic reactions. The self-thermophoresis behavior of the Janus nanomotor is monitored from its inherent plasmonic response. The diffusion coefficient of the self-thermophoresis motion is linearly dependent on chemical reaction rate, as described by a stochastic model.

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Triple-negative breast cancer (TNBC) lacks three important receptors, ER, PR, and HER2. It is more aggressive and more likely to relapse after treatment, thus has been identified as one of the most malignant breast cancer types. The development of efficient targeted TNBC therapy is an important research topic in TNBC treatment. We report the development of a new aptamer–drug conjugate (ApDC), AS1411–triptolide conjugate (ATC), as targeted therapy for the treatment of TNBC with high efficacy. The conjugate possesses excellent specificity and high cytotoxicity against the MDA-MB-231 cell line. The advantages of our newly invented ATC are further highlighted by its excellent in vivo anti-TNBC efficacy and negligible side effects toward healthy organs.

Glassy ferromagnetism is observed in diluted magnetic semiconductor Al-doped 4H-SiC. We propose a possible explanation for the origin of ferromagnetism order that is the coeffect of sp(2)/sp(3) configuration along with the structural defects. This result unambiguously demonstrates the existence of intrinsic ferromagnetism order in nonmagnetic sp systems.

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Mitomycin C (MMC) has been using for the treatment of a variety of digestive tract cancers. However, its nonspecific DNA-alkylating ability usually causes severe side effects, thus largely limiting its clinical applications. The utilization of an efficient active targeted drug delivery technique would address this issue. Accordingly, we report the design and development of aptamer−mitomycin C conjugates that use different cross-linking chemistry. The targeted delivery ability and cytotoxicity of these conjugates were carefully studied. It is worth noting that a linker-dependent cytotoxicity effect was observed for these conjugates. The use of a reductant-sensitive disulfide bond cross-linking strategy resulted in significantly enhanced cytotoxicity of MMC against the target cancer cell lines. Importantly, this cytotoxicity enhancement was suited to different types of aptamers, demonstrating the success of our design. Mechanistic studies of the enhanced cytotoxicity effect indicated that the target recognition, specific binding, and receptor-mediated internalization of aptamer were also critical for the observed effect.

Plasmon mediated photocatalysis provides a novel strategy for harvesting solar energy. Identification of rate determining step and its activation energy in plasmon mediated photocatalysis plays critical roles for understanding the contribution of hot carriers that facilitates rational designing catalysts with integrated high photo-chemical conversion efficiency and catalytic performance. However, it remains a challenge due to a lack of research tools with spatiotemporal resolution that capable of capturing intermediates. In this work, we used a single molecular fluorescence approach to investigate a localized surface plasmon resonance (LSPR) enhanced photocatalytic reaction with sub-turnover resolution. By introducing variable temperature as an independent parameter in plasmonic photocatalysis, the activation energies of tandem reaction steps, including intermediate generation, product generation and product dissociation, were clearly differentiated, and intermediates generation was found to be the rate-limiting step. Remarkably, the cause of plasmon enhanced catalysis performance was found to be its ability of lowering the activation energy of intermediates generation. This study gives new insight into the photo-chemical energy conversion pathways in plasmon enhanced photocatalysis and sheds light on designing high performance plasmonic catalysts. File list (2) download file view on ChemRxiv Main text-20191220.docx (2.01 MiB) download file view on ChemRxiv SI-20191220.docx (2.40 MiB)