Fast, sensitive, and selective ion-triggered disassembly and release based on tris(bipyridine)ruthenium(II)-functionalized metal-organic frameworks.

Metal-organic frameworks (MOFs) are microporous materials assembled from metal ions and organic linkers. Recently, many studies have been focused on the syntheses of MOFs with permanent porosity for various applications. However, no attention has been paid to controllable disassembly of MOFs and related applications. In this work, for the first time we synthesized novel tris(bipyridine)ruthenium(II)-functionalized MOFs (i.e., RuMOFs) that could be ion-responsively disassembled and release massive guest materials loaded in the frameworks. The synthesized RuMOFs exhibited much stability in aqueous solutions containing H(+), and many metal ions, but could be selectively and sensitively disassembled by Hg(2+) ions, resulting in the release of large quantities of Ru(bpy)3(2+). The target-responsive release mechanism was investigated and discussed in detail. On the basis of the ion-responsive disassembly and release, an ultrasensitive electrochemiluminescence sensing method for Hg(2+) has been developed with a very low limit of detection (5.3 × 10(-13) M). It was envisioned that the RuMOFs and similar target-responsive functional MOF materials would have promising applications in ultrasensitive and highly selective chemical sensing and even in accurately controllable drug delivering and releasing.

Encapsulation of strongly fluorescent carbon quantum dots in metal-organic frameworks for enhancing chemical sensing.

Novel highly fluorescent (FL) metal-organic frameworks (MOFs) have been synthesized by encapsulating branched poly-(ethylenimine)-capped carbon quantum dots (BPEI-CQDs) with a high FL quantum yield into the zeolitic imidazolate framework materials (ZIF-8). The as-synthesized FL-functionalized MOFs not only maintain an excellent FL activity and sensing selectivity derived from BPEI-CQDs but also can strongly and selectively accumulate target analytes due to the adsorption property of MOFs. The selective accumulation effect of MOFs can greatly amplify the sensing signal and specificity of the nanosized FL probe. The obtained BPEI-CQDs/ZIF-8 composites have been used to develop an ultrasensitive and highly selective sensor for Cu(2+) ion, with a wide response range (2-1000 nM) and a very low detection limit (80 pM), and have been successfully applied in the detection of Cu(2+) ions in environmental water samples. It is envisioned that various MOFs incorporated with FL nanostructures with high FL quantum yields and excellent selectivity would be designed and synthesized in similar ways and could be applied in sensing target analytes.

Application of lamina replantation with ARCH plate fixation in thoracic and lumbar intraspinal tumors.

The aim of the present study was to investigate the clinical effects of lamina replantation with ARCH plate fixation on patients with thoracic and lumbar intraspinal tumors, following laminectomy. Thirteen patients with thoracic and lumbar intraspinal tumors underwent total lamina replantation with ARCH plate fixation and repair of the supraspinous ligaments, following laminectomy and tumor enucleation. To investigate the clinical effect of lamina replantation with ARCH plate fixation, pre- and postoperative visual analog scale (VAS), and Oswestry Disability Index (ODI) scores were determined, and pre- and postoperative X-ray and magnetic resonance imaging (MRI) examinations were conducted. Computed tomography (CT) examinations were also included in the follow-up. No complications were observed pre- or postoperatively. The VAS and ODI results 2 weeks following surgery and at the final follow-up examination demonstrated a significant improvement compared with the corresponding preoperative results. The X-ray examination results indicated a satisfactory internal fixation location, without any characteristics of a fracture, lumbar scoliosis, kyphosis or instability. Following the surgery, the CT and MRI examination results demonstrated that healing of the lamina bone and repair of the supraspinous ligament had occurred without tumor recurrence or spinal epidural scar recompression. Two of the 13 cases were lost to follow-up. The results indicated that in patients with thoracic and lumbar intraspinal tumors, lamina replantation with ARCH plate fixation following total laminectomy is effective and provides thoracolumbar stability. Furthermore, this has been identified to be an effective technique for preventing intraspinal scar proliferation.

Electrochemiluminescence imaging-based high-throughput screening platform for electrocatalysts used in fuel cells.

High throughput screening is very important for accelerating the discovery of fuel cell catalysts. In this paper, a novel electrochemiluminescence (ECL, a technology changing electric current into light) imaging-based screening platform for electrocatalysts used in fuel cells has been developed. The ECL imaging-based screening platform consists of bipolar electrode array-bridged electrochemical (EC)/ECL twin cells, by which electrocatalytic reduction currents of O(2) can be imaged directly by ECL. The ECL imaging-based screening platform is simple in instrumentation, can image the "current-voltage" dependence directly, reversibly, and sensitively, and may enable the activities of electrocatalysts to be evaluated in a high-throughput way. The developed ECL imaging-based screening platform is envisioned to have promising applications in high throughput combinatorial screening of electrocatalysts for fuel cells.