The development of new principles and techniques with high neuronal compatibility for quantitatively monitoring the dynamics of neurochemicals is essential for deciphering brain chemistry and function but remains a great challenge. We herein report a neuron-compatible method for in vivo neurochemical sensing by powering a single carbon fiber through spontaneous bipolar electrochemistry as a new sensing platform. By using ascorbic acid as a model target to prove the concept, we found that the single-carbon-fiber-powered microsensor exhibited a good response, high stability and, more importantly, excellent neuronal compatibility. The microsensor was also highly compatible with electrophysiological recording, thus enabling the synchronous recording of both chemical and electrical signals. The sensing principle could be developed for in vivo monitoring of various neurochemicals in the future by rationally designing and tuning the electrochemical reactions at the two poles of the carbon fiber. 相似文献
SNPs, combined with massively parallel sequencing technology, have proven applicability in noninvasive prenatal paternity testing (NIPPT) for singleton pregnancies in our previous research, using circulating cell-free DNA in maternal plasma. However, the feasibility of NIPPT in twin pregnancies has remained uncertain. As a pilot study, we developed a practical method to noninvasively determine the paternity of twin pregnancies by maternal plasma DNA sequencing based on a massively parallel sequencing platform. Blood samples were collected from 15 pregnant women (twin pregnancies at 9–18 weeks of gestation). Parental DNA and maternal plasma cell-free DNA were analyzed with custom-designed probes covering 5226 polymorphic SNP loci. A mathematical model for data interpretation was established, including the zygosity determination and paternity index calculations. Each plasma sample was independently tested against the alleged father and 90 unrelated males. As a result, the zygosity in each twin case was correctly determined, prior to paternity analysis. Further, the correct biological father was successfully identified, and the paternity of all 90 unrelated males was excluded in each case. Our study demonstrates that NIPPT can be performed for twin pregnancies. This finding may contribute to development in NIPPT and diagnosis of certain genetic diseases. 相似文献
Highly crosslinked organic–inorganic hybrid polymer poly(cyclotriphosphazene-co-melamine) microspheres (PZM) were synthesized by a simple method. The microspheres was characterized by FTIR, SEM and EDX. It was applied to eliminate thorium(IV) from aqueous solution under various conditions, i.e., pH, initial concentration, dosage and contact time. The experimental data were well-imitated via the pseudo-second-order kinetic model and its adsorption processes comply with the Langmuir isotherm model. Adsorption thermodynamic studies demonstrated that the adsorption process, in essence, was spontaneous and endothermic. Furthermore, the maximum experimental adsorption capacity was 98.6 mg g?1 for initial thorium(IV) concentration 50 mg L?1. When pH?=?0.0, the thorium(IV) removal efficiency reached at 76.9%, which indicates that the adsorbent can also was used in a peracid environment. Adsorption behavior of thorium(IV) onto the microspheres were weakly affected via temperature, implying that adsorption would be done at room temperature.
This article describes a simple and homogeneous fluorescent aptasensor for the detection of ochratoxin A (OTA). With its high specificity and simplicity; RecJf exonuclease is used to cleave DNA strand of the FAM-aptamer/OTA complex and realize target recycling signal amplification. In order to avoid the loss of reaction system, magnetic beads (MBs) are added only once at the last experimental step. This proposed fluorescent aptasensor showed the higher sensitivity in the range of 0.1–100 ng/mL with LOD of 0.056 ng/mL, and the good selectivity against other interfering toxins. The feasibility of the prepared aptasensor was studied by detecting OTA in spiked liquor and cereal samples. The obtained average recoveries ranged from 92% to 115%. This study provides a promising application with convenience and rapidness in the aptasensor fabrication for food safety analysis. 相似文献
Luminescent metal nanoclusters (NCs) are emerging as a new class of functional materials that have rich physicochemical properties and wide potential applications. In recent years, it has been found that some metal NCs undergo aggregation-induced emission (AIE) and an interesting fluorescence-to-phosphorescence (F-P) switching in solutions. However, insights of both the AIE and the F-P switching remain largely unknown. Now, gelation of water soluble, atomically precise Ag9 NCs is achieved by the addition of antisolvent. Self-assembly of Ag9 NCs into entangled fibers was confirmed, during which AIE was observed together with an F-P switching occurring within a narrow time scale. Structural evaluation indicates the fibers are highly ordered. The self-assembly of Ag9 NCs and their photoluminescent property are thermally reversible, making the metal–organic gels good candidates for luminescent ratiometric thermometers. 相似文献
Two coordination polymers (CPs), namely, [Zn(BPDC)(3-bpdb)0.5(H2O)2]n ( 1 ), and [Ni(BPDC)(3-bpdb)(H2O)2]n ( 2 ) (where H2BPDC = 4,4'-biphenyldicarboxylic acid, 3-bpdb = 1,4-bis(3-pyridyl)-2,3-diaza-1,3-butadiene) have been solvothermally synthesized and characterized by single-crystal X-ray diffraction, IR, elemental analyses, PXRD, and SEM. CP 1 possesses a 2D 3-connected hcb net, and weak hydrogen bonding and π ··· π stacking contacts further link the 2D networks to form 3D supramolecular structure. The structure of 2 presents a 4-connected threefold interpenetrated cds framework. Through structural analysis, it is found that the coordination geometry of metal ions significantly affects the binding behaviors of the ligands and the resultant extended networks of the CPs. Besides, the Hirshfeld surface analyses detailed the surface characteristics of the two CPs. In addition, the thermal stabilities and photoluminescent properties were also investigated. 相似文献
The use of gold nanoparticles as radiosensitizers is an effective way to boost the killing efficacy of radiotherapy while drastically limiting the received dose and reducing the possible damage to normal tissues. Herein, we designed aggregation-induced emission gold clustoluminogens (AIE-Au) to achieve efficient low-dose X-ray-induced photodynamic therapy (X-PDT) with negligible side effects. The aggregates of glutathione-protected gold clusters (GCs) assembled through a cationic polymer enhanced the X-ray-excited luminescence by 5.2-fold. Under low-dose X-ray irradiation, AIE-Au strongly absorbed X-rays and efficiently generated hydroxyl radicals, which enhanced the radiotherapy effect. Additionally, X-ray-induced luminescence excited the conjugated photosensitizers, resulting in a PDT effect. The in vitro and in vivo experiments demonstrated that AIE-Au effectively triggered the generation of reactive oxygen species with an order-of-magnitude reduction in the X-ray dose, enabling highly effective cancer treatment. 相似文献
Expanding the number of nucleotides in DNA increases the information density of functional DNA molecules, creating nanoassemblies that cannot be invaded by natural DNA/RNA in complex biological systems. Here, we show how six-letter GACTZP DNA contributes this property in two parts of a nanoassembly: 1) in an aptamer evolved from a six-letter DNA library to selectively bind liver cancer cells; and 2) in a six-letter self-assembling GACTZP nanotrain that carries the drug doxorubicin. The aptamer-nanotrain assembly, charged with doxorubicin, selectively kills liver cancer cells in culture, as the selectivity of the aptamer binding directs doxorubicin into the aptamer-targeted cells. The assembly does not kill untransformed cells that the aptamer does not bind. This architecture, built with an expanded genetic alphabet, is reminiscent of antibodies conjugated to drugs, which presumably act by this mechanism as well, but with the antibody replaced by an aptamer. 相似文献
An N-confused phlorin isomer bearing a dipyrrin moiety at the α-position of the confused pyrrole ring ( 1 ) was synthesized. PdII and BIII coordination at the peripheral prodigiosin-like moiety of 1 afforded the corresponding complexes 2 and 3 . Reflux of 2 in triethylamine (TEA) converted the meso-phenyl into the PdII-coordinating phenoxy group to afford 4 . Under the same reaction conditions, TEA was linked to the α-position of the dipyrrin unit in 3 as an N,N-diethylaminovinyl group to afford 5 . Furthermore, peripheral coordination of BIII in 3 and 5 improved the planarity of the phlorin macrocycle and thus facilitated the coordination of AgIII at the inner cavity to afford 3-Ag and 5-Ag , respectively. These results provide an effective approach for developing unique porphyrinoids through peripheral coordination. 相似文献