We developed a novel strategy for rapid colorimetric analysis of a specific DNA sequence by combining gold nanoparticles (AuNPs) with an asymmetric polymerase chain reaction (As-PCR). In the presence of the correct DNA template, the bound oligonucleotides on the surface of AuNPs selectively hybridized to form complementary sequences of single-stranded DNA (ssDNA) target generated from As-PCR. DNA hybridization resulted in self-assembly and aggregation of AuNPs, and a concomitant color change from ruby red to blue-purple occurred. This approach is simpler than previous methods, as it requires a simple mixture of the asymmetric PCR product with gold colloid conjugates. Thus, it is a convenient colorimetric method for specific nucleic acid sequence analysis with high specificity and sensitivity. Most importantly, the marked color change occurs at a picogram detection level after standing for several minutes at room temperature. Linear amplification minimizes the potential risk of PCR product cross-contamination. The efficiency to detect Bacillus anthracis in clinical samples clearly indicates the practical applicability of this approach.

Osteoarthritis (OA) is a common joint degenerative disease that causes pain, joint damage, and dysfunction. External hyaluronic acid (HA) supplement is a common method for the management of osteoarthritis which requires multi‐injections. It is demonstrated that biodegradable mesoporous silica nanoparticles successfully deliver an enzyme, hyaluronan synthase type 2 (HAS2), into synoviocytes from the temporomandibular joint (TMJ) and generate endogenous HA with high molecular weights. In a rat TMJ osteoarthritis inflammation model, this strategy promotes endogenous HA production and inhibits the synovial inflammation of OA for more than 3 weeks with one‐shot administration. Such nanotherapy also helps repairing the bone defects in a rat OA bone defect model.

Herein, we demonstrate that Fe2O3 nanorod photoanodes modified with P-doping and a MnO2 oxygen evolution cocatalyst exhibited a remarkably enhanced PEC water oxidation activity.

Urea-formaldehyde (UF) microcapsules containing two-phase core materials in which phthalocyanine blue BGS (beta-CuPc) particles were homodispersed in tetrachloroethylene (TCE) were prepared by in situ polymerization. The effects of the various process parameters, including the type of surface modifier, the viscosity of UF prepolymer, the type of water-soluble surfactant, and the concentration of oil-soluble surfactant in the capsule core on the dispersity of beta-CuPc particles in TCE and the properties of the capsule wall and the adsorption of beta-CuPc particles on the internal surface of capsule wall were experimentally investigated. It was shown that using octadecylamine (ODA) to modify beta-CuPc particles resulted in a significant increase of the dispersing extent (DE) and the electrophoresis velocity of the particles in TCE (about 4 and 20 times more than that of unmodified). In addition, the optimal reaction conditions of the synthesis UF prepolymer were obtained by the orthogonal test. On the other hand, as the oil/water interfacial tension of emulsion was big enough, the microcapsule formed. The concentration of Span-80 in TCE was no less than 0.062 mM; the adsorption of beta-CuPc particles on internal surface of wall were restrained. Finally, the microcapsules in which beta-CuPc particles possess reversible response to dc electric field were obtained.