Tunable fiber attenuator for electrically wet-driven micromirrors.

Herein we report an electronically controlled tunable fiber-optic attenuator that leverages the microfluidic electro-wetting effect, which enables a fine-tuning of the solid-liquid interface wetting angle to control the micro-reflector, thus regulating the lens fiber coupling efficiency. Theoretical calculations indicated an optical attenuation regulation effect of 0-45.0 dB in the voltage range of 0-30.

A colorimetric indicator-displacement assay based on stable Cu selective carbon dots for fluorescence turn-on detection of pyrophosphate anions in urine.

Determination of PPi levels in urine represents a measurable factor for diagnostic, treatment, and monitoring of urolithiasis. Owing to the quenching ability of Cu on fluorescent carbon dots (CDs) and strong binding affinity between Cu and PPi, we develop a new off-on assay for PPi detection using newly BPHA CDs (BPHA: N,N-bis(pyridin-2-ylmethyl)hexan-1-amine). The fluorescence intensity of BPHA CDs was significantly quenched by Cu ("off") through forming BPHA CDs/Cu complexes and the fluorescence intensity of BPHA CDs /Cu system was completely resumed by PPi ("on") owing to the release of free Cu.

Targeting Energy Metabolism by a Platinum(IV) Prodrug as an Alternative Pathway for Cancer Suppression.

Cancer is characterized by abnormal cellular energy metabolism, which preferentially switches to aerobic glycolysis rather than oxidative phosphorylation as a means of glucose metabolism. Many key enzymes involved in the abnormal glycolysis are potential targets of anticancer drugs. Platinum(IV) complexes are potential anticancer prodrugs and kinetically more inert than the platinum(II) counterparts, which offer an opportunity to be modified by functional ligands for activation or targeted delivery.

Restraining Cancer Cells by Dual Metabolic Inhibition with a Mitochondrion-Targeted Platinum(II) Complex.

Cancer cells usually adapt metabolic phenotypes to chemotherapeutics. A defensive strategy against this flexibility is to modulate signaling pathways relevant to cancer bioenergetics. A triphenylphosphonium-modified terpyridine platinum(II) complex (TTP) was designed to inhibit thioredoxin reductase (TrxR) and multiple metabolisms of cancer cells.

Impact of Mitochondrion-Targeting Group on the Reactivity and Cytostatic Pathway of Platinum(IV) Complexes.

Platinum(IV) complexes are prodrugs of cisplatin with multiple potential advantages over platinum(II) drugs. Mitochondria play pivotal roles in producing energy and inducing death of cancer cells. Two platinum(IV) complexes, namely, c,c,t-[Pt(NH)Cl(OH)(OCOCHCHCHCHPPh)]Br and c,c,t-[Pt(NH)Cl(OCOCHCHCHCHPPh)]Br, were designed to explore the effect of mitochondrion-targeting group(s) on the bioactivity and cytotoxicity of platinum(IV) complexes.

A Potential Bone-Targeting Hypotoxic Platinum(II) Complex with an Unusual Cytostatic Mechanism toward Osteosarcoma Cells.

Osteosarcoma (OS) is the most common primary pediatric bone tumor lethal to children and adolescents. Chemotherapeutic agents such as cisplatin are not effective for OS because of their poor accessibility to this cancer and severe systemic toxicity. In this study, a lipophilic platinum(II) complex bearing a bisphosphonate bone-targeting moiety, cis-[PtL(NH)Cl]NO {BPP; L = tetraethyl [2-(pyridin-2-yl)ethane-1,1-diyl]bisphosphonate}, was prepared and characterized by NMR, electrospray ionization mass spectrometry, and single-crystal X-ray crystallography.

Dinuclear Platinum(II) Complexes with Bone-Targeting Groups as Potential Anti-Osteosarcoma Agents.

Osteosarcoma is the most common malignant bone tumor primarily affecting adolescents. Targeted platinum(II) complexes are promising candidates for overcoming the general toxicity of conventional platinum anticancer drugs. In this study four dinuclear platinum(II) complexes, {[cis-Pt(NH ) Cl] (PD)} (NO ) (1), {[cis-Pt(NH ) Cl] (PDBP)} (NO ) (2), {[cis-Pt(DACH)Cl] (PD)} (NO ) (3), and {[cis-Pt(DACH)Cl] (PDBP)} (NO ) (4) [PD=5,5'-carbonylbis(2-(2-(pyridin-2-yl)ethyl)isoindoline-1,3-dione), PDBP=tetraethyl (((bis(1,3-dioxo-2-(2-(pyridin-2-yl)ethyl)isoindolin-5-yl)methylene)amino) methylene)bis(phosphonate), DACH=1,2-diaminocyclohexane)], were designed and synthesized.

Simultaneous electrochemical detection of ascorbic acid, dopamine and uric acid based on graphene anchored with Pd-Pt nanoparticles.

Pd-Pt bimetallic nanoparticles anchored on functionalized reduced graphene oxide (RGO) nanomaterials were synthesized via a one-step in situ reduction process, in which Pt and Pd ions were first attached to poly(diallyldimethylammonium chloride) (PDDA) functionalized graphene oxide (GO) sheets, and then the encased metal ions and GO were subjected to simultaneous reduction by ethylene glycol. The as-prepared Pd3Pt1/PDDA-RGO nanocomposites were characterized by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and electrochemical methods. In addition, an electrochemical sensor based on the graphene nanocomposites was fabricated for the simultaneous detection of ascorbic acid (AA), dopamine (DA) and uric acid (UA) in their ternary mixture.

4-(4-Pyrid-yl)pyridinium penta-aqua(pyridazine-4,5-dicarboxyl-ato)praseodymate(III).

In the title complex, (C(10)H(9)N(2))[Pr(C(6)H(2)N(2)O(4))(2)(H(2)O)(5)], the Pr atom is nine-coordinated by nine O atoms from two pyridazine-4,5-dicarboxyl-ate anions and five water mol-ecules. It is noteworthy that there is a protonated bipyridine mol-ecule in the structure. Inter-molecular O-H⋯O, O-H⋯N and N-H⋯N hydrogen bonds are present, resulting in a three-dimensional network.

Dichlorido(N,N'-diisopropyl-piperidine-1-carboximidamidato-κN,N')titanium(IV).

In the mononuclear title complex, [Ti(C(12)H(24)N(3))(2)Cl(2)], the Ti(IV) ion, located on a crystallographic inversion center, is six-coordinated by four N atoms from two N',N''-diisopropyl-N-carboxamidine anions and two chloride atoms in a distorted octahedral geometry. The dihedral angles between the piperidine groups and the NCN chelate rings are 51.5 (1) and 52.

Synthesis, reactivity, and characterization of sodium and rare-earth metal complexes bearing a dianionic N-aryloxo-functionalized beta-ketoiminate ligand.

The synthesis and reactivity of a series of sodium and rare-earth metal complexes stabilized by a dianionic N-aryloxo-functionalized beta-ketoiminate ligand were presented. The reaction of acetylacetone with 1 equiv of 2-amino-4-methylphenol in absolute ethanol gave the compound 4-(2-hydroxy-5-methylphenyl)imino-2-pentanone (LH2, 1) in high yield. Compound 1 reacted with excess NaH to afford the novel sodium cluster [LNa2(THF)2]4 (2) in good isolated yield.

Determination of penehyclidine by gas chromatographic-mass spectrometry and its application to pharmacokinetics in humans, rabbits and mice.

A sensitive and specific gas chromatographic-mass spectrometry with the extracted ion chromatograms (GC-MS/EIC) method has been developed and validated for the identification and quantification of penehyclidine (PH) in human and animal blood. The chromatography was on HP-5 capillary column (12 m x 0.2 mm x 0.

Synthesis and structural characterization of beta-diketiminate-lanthanide amides and their catalytic activity for the polymerization of methyl methacrylate and epsilon-caprolactone.

The synthesis and catalytic activity of lanthanide monoamido complexes supported by a beta-diketiminate ligand are described. Donor solvents, such as DME, can cleave the chloro bridges of the dinuclear beta-diketiminate ytterbium dichloride {[(DIPPh)2nacnac]YbCl(mu-Cl)3Yb[(DIPPh)2nacnac](THF)} (1) [(DIPPh)2nacnac = N,N-diisopropylphenyl-2,4-pentanediimine anion] to produce the monomeric complex [(DIPPh)2nacnac]YbCl2(DME) (2) in high isolated yield. Complex 2 is a useful precursor for the synthesis of beta-diketiminate-ytterbium monoamido derivatives.