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In this experimental research, a label-free sensing strategy is developed and employed to detect adenosine triphosphate with utilization of aptamers, including exonuclease I and SYBR Gold. The conformation of aptamers bonding to the specific target molecule (ATP) is transformed into an antiparallel G-quadruplex structure from a random coil. Afterwards, considering the unfolded aptamers are the preferred substrates for exonuclease I, the addition of exonuclease I is used so as to digest unfolded aptamers in the mixture in a selective manner. In the follow-up study, in order to strengthen the fluorescence intensity, SYBR Gold is applied as a fluorescent probe. The aptasensor presents the features of high selectivity against adenosine triphosphate and the low detecting limit of concentrations (39.2 nM). In order to verify the validation of experimental procedures and the practical application of the aptasensor, the detection of adenosine triphosphate for human serum samples is performed with satisfactory success. The recovery result with the range of 93.8%–108.1% is desirable and suggests that the designed approach is applicable. The outcomes of the cellular adenosine triphosphate assay manifest that the level of adenosine triphosphate concentrations in cell extracts can be monitored without the interference of other substances in the cells. Subject to its advantageous benefits (cost-effective, easiness, rapidity, and extraordinary selectivity), the designed approach has a promising implication for adenosine triphosphate detection in the research domain of bioanalytical science and biology. Graphical Abstract [ABSTRACT FROM AUTHOR]

Main observation and conclusion: One near‐infrared (NIR) luminescent octanuclear Zn(II)‐Yb(III) complex [Zn6Yb2L4(OAc)2(DMF)EtOH] (1) was obtained from a new multidentate Schiff base ligand. It exhibits interesting luminescent sensing activity to antibiotics, in particular to nitrofuran antibiotics (NFAs) with high sensitivity due to the inner filter effect. The NIR luminescence quenching constants and limits of the detection of the complex towards NFAs are 2.9 × 104—5.5 × 104 L/mol and 1.27—2.38 μmol/L, respectively. Its high luminescence sensitivity to NFAs is not changed with the existence of other antibiotics. [ABSTRACT FROM AUTHOR]

A functionalization of benzylic C(sp3)–H bonds was established through a mild metal-free intramolecular lactonization protocol in the presence of DDQ/ tert -butyl nitrite as photocatalysts, allowing practical and low-cost access to a series of phthalide products in moderate to excellent yields. Compared with many existing methodologies, this visible-light-driven process exhibits an excellent substrate scope and fascinating features, including the formation of water as the sole byproduct, an abundant and green energy source, commercially available catalysts, and room-temperature reaction. Finally, detailed mechanistic investigations clearly revealed the role of the photocatalysts and molecular oxygen. [ABSTRACT FROM AUTHOR]

Two NIR luminescent "bi-decker" and "tetra-decker" Cd(II)-Yb(III) and Nd(III) clusters 1 and 2 were synthesized from a new salen-type Schiff base ligand. 2 exhibits rapid ratiometric fluorescence response to Que with high sensitivity. The quenching constants of Que to the ligand-centered and lanthanide emissions of 2 are 2.9 × 104 M−1 and 3.8 × 104 M−1, respectively. The detection limits to Que are 6.75 μ M for the ligand-centered emission and 2.03 μ M for the lanthanide luminescence. The response of 2 to Que is not influenced by some potential interferents such as biomolecules and ions. [Display omitted] • The complexes show "bi-decker" and "tetra-decker" structures. • The complexes display typical NIR lanthanide luminescence. • The "tetra-decker" complex exhibits lanthanide luminescent response towards Que. [ABSTRACT FROM AUTHOR]

A nanoscale Yb(III) complex [Yb 6 (L1) 2 (L2) 4 (OH) 4 (CF 3 SO 3) 2 (DMF) 2 (EtOH) 4 ]·2(CF 3 SO 3)·2OH (1) with Schiff base ligand N,N′-bis(3-methoxysalicylidene)(binaphthyl)-1,4-diamine (H 2 L1) and salicylaldehyde ligand 3-methoxysalicylaldehyde (H 2 L2) was synthesized. Upon excitation of the ligand-centered absorption bands, 1 displays typical NIR luminescence of Yb(III). Interestingly, it shows lanthanide luminescence response to anions and nitro explosives, especially with high sensitivity to F− and PA. Meanwhile, the quenching effect of F− and PA to the lanthanide luminescence of 1 is not affected by the existence of other anions and explosives. Image 1 • The complex shows a nanoscale blocky structure. • The complex displays typical NIR lanthanide luminescence. • The complex exhibits NIR luminescence response to anions and explosives. [ABSTRACT FROM AUTHOR]

Streamer behaviors, related to discharge patterns, can determine the distribution of active species, which play an important role in the applications of the plasma jet. In this article, petal‐like patterns formed on the substrate are observed for the first time downstream of an argon plasma jet. The penta‐petalous pattern is taken as an example to discuss the pattern formation mechanism, which results from two positive discharges (Dp1 and Dp2) and one negative discharge (Dn) in every voltage cycle. Fast photography is implemented to reveal the complicated streamer dynamics of Dp2. Results indicate that Dp2 with a low Q undergoes a stripe phase, a homogeneous phase, and a branch phase. The complicated streamer dynamics of Dp2 are analyzed based on optical emission spectra. [ABSTRACT FROM AUTHOR]

A 18-metal Yb(III) nanoring was constructed by the using of a Schiff base ligand. It exhibits interesting NIR luminescent sensing behavior to antibiotics and explosives, in particular to NFAs and TNP with high sensitivity. The K SV values and LODs of this lanthanide nanoring to NFAs and TNP are 1.5 × 104–4.6 × 104 (mol/L)−1 and 1.7–5.1 μmol/L, respectively. Its high luminescence sensitivities to NFAs and TNP are not affected by the existence of other antibiotics and explosives. [Display omitted] • The complex shows a ring-like structure. • The complex displays typical NIR lanthanide luminescence. • The complex exhibits NIR luminescence response to antibiotics and explosives. [ABSTRACT FROM AUTHOR]

One 18-metal Eu(III) nanoring (size: 1.0 × 2.7 × 2.7 nm) was constructed as a rapid ratiometric fluorescent probe for the detection of dipicolinic acid with high sensitivity and selectivity, by using two types of polydentate organic ligands. [ABSTRACT FROM AUTHOR]

One NIR luminescent 14-metal Nd(III) nanoring (1, molecular size: 1.0 × 2.2 × 2.6 nm) was obtained from a rigid tridentate ligand, which can absorb and transfer light energy to the Nd(III) ions. 1 shows interesting luminescence sensing activity to antibiotics, in particular to NFAs with high sensitivity due to the inner filter effect. The quenching constants and the limits of detection of 1 to NFAs are 1.05 × 104 M−1–2.33 × 104 M−1 and 3.05 μM–6.75 μM, respectively. The high fluorescence sensitivities of 1 to NFAs are not changed by the existence of other antibiotics. It also exhibits high sensitivity in the luminescent detection of NFAs contained in real antibiotic drugs. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: One six‐metal Zn(II)‐Yb(III) complex [Zn2Yb4L2(OAc)10(OH)2(CH3OH)2] (1) was constructed from Schiff base ligand bis(3‐methoxysalicylidene)ethylene‐1,2‐phenylenediamine (H2L). 1 shows a nanoscale rectangular structure with dimensions of approximately 0.8 nm × 1.1 nm × 2.8 nm. Excited by ligand‐centered absorption bands, 1 shows typical near‐infrared emission of Yb3+ ion. Interestingly, 1 exhibits lanthanide luminescent response towards metal ions, especially to Cd2+ at ppm level. [ABSTRACT FROM AUTHOR]

Two 14-metal lanthanide nanorings [Ln14(HL)2L20(DMF)8(H2O)8] (Ln = Nd(1) and Gd(2)) were constructed from a tridentate ligand. 1 displays NIR luminescence sensing properties towards metal cations and anions, especially Cu2+, Co2+, H2PO4− and F− at a ppm level. [ABSTRACT FROM AUTHOR]

Two 4f and 3d-4f complexes [Yb 3 L 3 (OAc) 3 (1) and [Zn 2 NdL 2 (OAc) 3 (2) were constructed from Schiff base ligand N,N′-bis(3-methoxysalicylidene)(4-methylphenylene)-1,2-diamine (H 2 L). 1 shows a chiral "triple-decker" structure with Yb3+ ions sandwiched between the alternating layers of Schiff base ligands, while 2 exhibits a "cross" structure with the Nd3+ ion clipped by two ZnL groups. Open 3D channel structures running along the a -axis are formed in the solid state of 1 and 2. Excited by ligand-centered absorption bands, 1 and 2 show typical NIR emission of Yb3+ and Nd3+, respectively. Interestingly, 2 exhibits lanthanide luminescent response towards anions, especially to CN− and OAc− at ppm level. Image 1 • The complexes show "triple-decker" and "cross" structures. • The complexes display typical NIR lanthanide luminescence. • The Zn–Nd complex exhibits lanthanide luminescent response towards anions. [ABSTRACT FROM AUTHOR]