Multiplexed Organelles Portrait Barcodes for Subcellular MicroRNA Array Detection in Living Cells

Multiplexed profiling of microRNAs’ subcellular expression and distribution is essential to understand their spatiotemporal function information, but it remains a crucial challenge. Herein, we report an encoding approach that leverages combinational fluorescent dye barcodes, organelle targeting elements, and an independent quantification signal, termed Multiplexed Organelles Portrait Barcodes (MOPB), for high-throughput profiling of miRNAs from organelles. The MOPB barcodes consist of heterochromatic fluorescent dye-loaded shell–core mesoporous silica nanoparticles modified with organelle targeting peptides and molecular beacon detection probes. Using mitochondria and endoplasmic reticulum as models, we encoded four Cy3/AMCA ER-MOPB and four Cy5/AMCA Mito-MOPB by varying the Cy3 and Cy5 intensity for distinguishing eight organelles’ miRNAs. Significantly, the MOPB strategy successfully and accurately profiled eight subcellular organelle miRNAs’ alterations in the drug-induced Ca2+ homeostasis breakdown. The approach should allow more widespread application of subcellular miRNAs and multiplexed subcellular protein biomarkers’ monitoring for drug discovery, cellular metabolism, signaling transduction, and gene expression regulation readout

Oxidative Unzipping of Stacked Nitrogen-Doped Carbon Nanotube Cups

We demonstrate a facile synthesis of different nanostructures by oxidative unzipping of stacked nitrogen-doped carbon nanotube cups (NCNCs). Depending on the initial number of stacked-cup segments, this method can yield graphene nanosheets (GNSs) or hybrid nanostructures comprised of graphene nanoribbons partially unzipped from a central nanotube core. Due to the stacked-cup structure of as-synthesized NCNCs, preventing complete exposure of graphitic planes, the unzipping mechanism is hindered, resulting in incomplete unzipping; however, individual, separated NCNCs are completely unzipped, yielding individual nitrogen-doped GNSs. Graphene-based materials have been employed as electrocatalysts for many important chemical reactions, and it has been proposed that increasing the reactive edges results in more efficient electrocatalysis. In this paper, we apply these graphene conjugates as electrocatalysts for the oxygen reduction reaction (ORR) to determine how the increase in reactive edges affects the electrocatalytic activity. This investigation introduces a new method for the improvement of ORR electrocatalysts by using nitrogen dopants more effectively, allowing for enhanced ORR performance with lower overall nitrogen content. Additionally, the GNSs were functionalized with gold nanoparticles (GNPs), resulting in a GNS/GNP hybrid, which shows efficient surface-enhanced Raman scattering and expands the scope of its application in advanced device fabrication and biosensing

A Novel Dual Amino-Functionalized Cation-Tethered Ionic Liquid for CO₂ Capture

A novel dual amino-functionalized ionic liquid, 1, 3-di (2′-aminoethyl)-2-methylimidazolium bromide (DAIL), was synthesized and investigated as a potential absorbent for CO₂ capture. CO₂ absorption behavior on pressure, temperature and concentrations of DAIL in aqueous solution were studied, and the absorption mechanism was investigated by spectroscopic methods and DFT calculations. The CO₂ capture capacity of 18.5 wt % and good thermal stability (<i>T</i>_d = 521.6 K) make DAIL a good candidate for industrial applications for CO₂ capture

Fabricating Pt/Sn–In₂O₃ Nanoflower with Advanced Oxygen Reduction Reaction Performance for High-Sensitivity MicroRNA Electrochemical Detection

Herein, an efficient electrochemical tracer with advanced oxygen reduction reaction (ORR) performance was designed by controllably decorating platinum (Pt) (diameter, 1 nm) on the surface of compositionally tunable tin-doped indium oxide nanoparticle (Sn–In₂O₃) (diameter, 25 nm), and using the Pt/Sn–In₂O₃ as electrochemical tracer and interfacial term hairpin capture probe, a facile and ultrasensitive microRNA (miRNA) detection strategy was developed. The morphology and composition of the generated Pt/Sn–In₂O₃ NPs were comprehensively characterized by spectroscopic and microscopic measurements, indicating numerous Pt uniformly anchored on the surface of Sn–In₂O₃. The interaction between Pt and surface Sn as well as high Pt(111) exposure resulted in the excellent electrochemical catalytic ability and stability of the Pt/Sn–In₂O₃ ORR. As proof-of-principle, using streptavidin (SA) functionalized Pt/Sn–In₂O₃ (SA/Pt/Sn–In₂O₃) as electrochemical tracer to amplify the detectable signal and a interfacial term hairpin probe for target capture probe, a miRNA biosensor with a linear range from 5 pM to 0.5 fM and limit of detection (LOD) down to 1.92 fM was developed. Meanwhile, the inherent selectivity of the term hairpin capture probe endowed the biosensor with good base discrimination ability. The good feasibility for real sample detection was also demonstrated. The work paves a new avenue to fabricate and design high-effective electrocatalytic tracer, which have great promise in new bioanalytical applications

Aptamer-Conjugated Graphene Quantum Dots/Porphyrin Derivative Theranostic Agent for Intracellular Cancer-Related MicroRNA Detection and Fluorescence-Guided Photothermal/Photodynamic Synergetic Therapy

Multifunctional theranostic platform coupling diagnostic and therapeutic functions holds great promise for personalized nanomedicine. Nevertheless, integrating consistently high performance in one single agent is still challenging. This work synthesized a sort of porphyrin derivatives (P) with high singlet oxygen generation ability and graphene quantum dots (GQDs) possessing good fluorescence properties. The P was conjugated to polyethylene glycol (PEG)­ylated and aptamer-functionalized GQDs to gain a multifunctional theranostic agent (GQD-PEG-P). The resulting GQD-PEG-P displayed good physiological stability, excellent biocompatibility and low cytotoxicity. The intrinsic fluorescence of the GQDs could be used to discriminate cancer cells from somatic cells, whereas the large surface facilitated gene delivery for intracellular cancer-related microRNA (miRNA) detection. Importantly, it displayed a photothermal conversion efficiency of 28.58% and a high quantum yield of singlet oxygen generation up to 1.08, which enabled it to accomplish advanced photothermal therapy (PTT) and efficient photodynamic therapy (PDT) for cancer treatment. The combined PTT/PDT synergic therapy led to an outstanding therapeutic efficiency for cancer cell treatment

Intelligent MnO₂/Cu_2–<i>x</i>S for Multimode Imaging Diagnostic and Advanced Single-Laser Irradiated Photothermal/Photodynamic Therapy

Lately, photothermal therapy (PTT) and photodynamic therapy (PDT) dual-modal therapy has attracted much attention in cancer therapy as a synergistic therapeutic model. However, the integration of PDT and PTT in a single nanoagent for cancer therapy is still a challenging task. Herein, an intelligent MnO₂/Cu_2–<i>x</i>S-siRNA nanoagent simultaneously overcoming inherent limitations of PDT and PTT with remarkable PTT&PDT therapeutic efficiency enabling a multimode accurate tumor imaging diagnostic is designed. We first develop a general method to decorate Cu_2–<i>x</i>S on the surface of MnO₂ nanosheet (MnO₂/Cu_2–<i>x</i>S); then, it is loaded with heat shock protein (HSP) 70 siRNA to obtain MnO₂/Cu_2–<i>x</i>S-siRNA. The intracellular microRNA (miRNA) imaging can be realized by loading miRNA detection probes. In the tumor acidic microenvironment, the MnO₂ is reduced to Mn²⁺ ion and triggers the decomposition of H₂O₂ into O₂ to relieve tumor hypoxia. The reduced Mn²⁺ ions significantly enhance magnetic resonance imaging (MRI) contrast, and the Cu_2–<i>x</i>S acts as a powerful photoacoustic (PA) and photothermal (PT) imaging agent, leading to trimodal accurate tumor-specific imaging and detection. Under a single NIR laser irradiation, the nanosystem exhibits superiority of PTT&PDT efficiency owing to siRNA-mediated blocked heat-shock response and MnO₂-related relieved tumor hypoxia. This work highlights the great promise of modulating the tumor cellular defense mechanism and microenvironment with intelligent multifunctional nanoagents to achieve a comprehensive fighting cancer effect

Functionalized Graphene Oxide Mediated Adriamycin Delivery and miR-21 Gene Silencing to Overcome Tumor Multidrug Resistance <em>In Vitro</em>

<div><p>Multidrug resistance (MDR) is a major impediment to successful cancer chemotherapy. Co-delivery of novel MDR-reversing agents and anticancer drugs to cancer cells holds great promise for cancer treatment. MicroRNA-21 (miR-21) overexpression is associated with the development and progression of MDR in breast cancer, and it is emerging as a novel and promising MDR-reversing target. In this study, a multifunctional nanocomplex, composed of polyethylenimine (PEI)/poly(sodium 4-styrenesulfonates) (PSS)/graphene oxide (GO) and termed PPG, was prepared using the layer-by-layer assembly method to evaluate the reversal effects of PPG as a carrier for adriamycin (ADR) along with miR-21 targeted siRNA (anti-miR-21) in cancer drug resistance. ADR was firstly loaded onto the PPG surface (PPG_ADR) by physical mixing and anti-miR-21 was sequentially loaded onto PPG_ADR through electric absorption to form ^anti-miR-21PPG_ADR. Cell experiments showed that PPG significantly enhanced the accumulation of ADR in MCF-7/ADR cells (an ADR resistant breast cancer cell line) and exhibited much higher cytotoxicity than free ADR, suggesting that PPG could effectively reverse ADR resistance of MCF-7/ADR. Furthermore, the enhanced therapeutic efficacy of PPG could be correlated with effective silencing of miR-21 and with increased accumulation of ADR in drug-resistant tumor cells. The endocytosis study confirmed that PPG could effectively carry drug molecules into cells via the caveolae and clathrin-mediated endocytosis pathways. These results suggest that this PPG could be a potential and efficient non-viral vector for reversing MDR, and the strategy of combining anticancer drugs with miRNA therapy to overcome MDR could be an attractive approach in cancer treatment.</p> </div

<i>In vitro</i> miR-21 and ABCB1 expression.

<p>Real time PCR analysis of relative miR-21 expression (A) and ABCB1 expression (B) in MCF-7 and MCF-7/ADR cells treated with ^ncRNAPPG and ^anti-miR-21PPG. The expression of miR-21 and ABCB1 in MCF-7 cells treated with ^ncRNAPPG were arbitrarily set as 1. Data are means ± SD for three separate experiments, ***P<0.001.</p

Fabrication of PPG_ADR, ^anti-miR-21PPG and ^anti-miR-21PPG_ADR.

<p>(A) UV-Vis spectra of ADR, PPG, PPG_ADR and ^anti-miR-21PPG_ADR in aqueous solution; (B) Electrophoretic mobility of anti-miR-21 with PPG_ADR at different volume ratios.</p

Characterization by flow cytometry of PPG co-delivering anti-miR-21 and ADR.

<p>MCF-7/ADR cells were incubated with PPG_ADR, ^{FAM-anti-miR-21}PPG, ^{FAM-anti-miR-21}PPG_ADR at 37°C for 4 h and harvested for flow cytometry analysis. Cells treated with blank PPG served as a control.</p