Coacervate microdroplets, formed liquid-liquid phase separation, have been proposed as a compartment model for the construction of artificial cells or organelles. However, these microsystems are very fragile and demonstrate liquid-like fluidity. Here, an artificial cytoskeleton based on DNA nanotubes was constructed in coacervate microdroplets to modulate the liquid fluidic properties of the microdroplets.
View Article and Find Full Text PDFDespite DNA nanotechnology has spawned a broad variety and taken a giant leap toward cancer theranostic applications over the last decade, the homogeneous DNA nanostructures often suffer from fatal degradation due to their limited stability and specificity. Herein, for the first time, we report a stable DNA tetrahedra-gold nanoclusters (DT/AuNCs) nanohybrid with a self-assembly/programmed disassembly manner for stimuli-responsive tumor imaging and gene-chemo therapy. By utilizing the multifunctional peptides with positive and legumain-specific domains as bioligands, AuNCs were synthesized as signal generators and gate guard attached on the dual-responsive DT, forming the DT/AuNCs with sequential response to legumain-TK1 mRNA & glutathione.
View Article and Find Full Text PDFEndogenous miRNA expression patterns are extremely cell-type-specific, thereby offering high prediction accuracy for different cell identities. Here, a DNA-tetrahedron-based "AND" logic gate is utilized as a molecular device that recognizes dual-miRNA inputs through strand hybridization to activate a computation cascade that produces controlled singlet oxygen in live cells, resulting in the death of the target cell.
View Article and Find Full Text PDFExisting drug delivery systems were not suitable for killing cells in the circulatory system specifically. Herein, we developed a novel localized drug delivery strategy, in which the release of anticancer agents was specifically triggered by circulating tumor cells. Meanwhile, damage to non-target cells was avoided.
View Article and Find Full Text PDFZhongguo Zhong Yao Za Zhi
October 2012
Hashimoto's thyroiditis (HT) is a autoimmune disease that is highly incident year by year. Its clinical manifestations are alternative hyperthyroidism or hypothyroidism, relatively high Th1, excessively low Th2 and constantly increasing TGAb and TMAB. Currently, the disease is still difficult to be cured, and instable thyroid function makes it harder to be treated.
View Article and Find Full Text PDFPhospholipid quantum dot (QD) micelles have been extensively used as fluorescent tags in single nanoparticle imaging for biomedical imaging. In this work, the microscopic structures and photophysical properties of the phospholipid QD micelles were studied at the single nanoparticle level. Two commonly used types of phospholipid QD micelles were prepared and tested both on a solid-phase surface and in liquid phase, including 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-encapsulated QD micelles (DSPE-QDMs) and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-2000]-encapsulated QD micelles (PEG-DSPE-QDMs).
View Article and Find Full Text PDFJ Nanosci Nanotechnol
April 2011
The biosynthesis of silver nanoparticles (AgNPs) has been successfully conducted by reduction of silver nitrate with sun-dried mulberry leaf. Such AgNPs have been characterized by UV-visible spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, high-resolution transmission electron microscopy (HRTEM) and atomic force microscopy (AFM). The results showed that such dispersed, uniform and spherical AgNPs would not aggregate under high-concentration NaCl solution and have good antibacterial activity.
View Article and Find Full Text PDFAn electrochemical method for nicotinamide adenine dinucleotide (NAD(+)) detection with high sensitivity and selectivity has been developed by using molecular beacon (MB)-like DNA and Escherichia coli DNA ligase. In this method, MB-like DNA labeled with 5'-SH and 3'-biotin was self-assembled onto a gold electrode in its duplex form by means of facile gold-thiol chemistry, which resulted in blockage of electronic transmission. It was eT OFF state.
View Article and Find Full Text PDFThere is increasing interest in developing bioconjugated carriers for the cellular delivery of bioactive molecules to stem cells, since they can allow modulation of stem cell differentiation. The present study reported biocompatible silica nanoparticle-insulin conjugates for rat mesenchymal stem cell (RMSC) adipogenic differentiation in vitro. A systematic study was first carried out on the biocompatibility of the SiNPs with RMSCs.
View Article and Find Full Text PDFThis letter described the design and synthesis of a novel fluorescein-appended rhodamine spirolactam derivative and its preliminary application as a ratiometric fluorescent cellular imaging probe for Zn(2+). The ratiometric fluorescent signal change of the probe is based on an intramolecular fluorescence resonance energy transfer (FRET) mechanism modulated by a specific metal ion induced ring-opening process of the rhodamine spirolactam (acting as a trigger). In the new developed sensing system, the emission peaks of the two fluorophores are well-resolved, which can avoid the emission spectra overlap problem generally met by spectra-shift type probes and benefits for observation of fluorescence signal change at two different emission wavelengths with high resolution.
View Article and Find Full Text PDFIn this paper, we unveil a novel naphthalimide-porphyrin hybrid based fluorescence probe (1) for ratiometric detection of Hg(2+) in aqueous solution and living cells. The ratiometric signal change of the probe is based on a carefully predesigned molecule containing two independent Hg(2+)-sensitive fluorophores with their maximal excitation wavelengths located at the same range, which shows reversibly specific ratiometric fluorescence responses induced by Hg(2+). In the new developed sensing system, the emissions of the two fluorophores are well-resolved with a 125 nm difference between two emission maxima, which can avoid the emission spectra overlap problem generally met by spectra-shift type probes and is especially favorable for ratiometric imaging intracellular Hg(2+).
View Article and Find Full Text PDFThe design and synthesis of a novel rhodamine spirolactam derivative and its application in fluorescent detections of Cu(2+) in aqueous solution and living cells are reported. The signal change of the chemosensor is based on a specific metal ion induced reversible ring-opening mechanism of the rhodamine spirolactam. It exhibits a highly sensitive "turn-on" fluorescent response toward Cu(2+) in aqueous solution with an 80-fold fluorescence intensity enhancement under 10 equiv of Cu(2+) added.
View Article and Find Full Text PDF