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A cube-like Zn(II)-Eu(III) nanocluster 1 (molecular sizes: 1.8 × 2.0 × 2.0 nm) was constructed by the use of a new long-chain Schiff base ligand. It shows a ratiometric fluorescence response to levofloxacin (LFX) with high sensitivity and selectivity, which can be expressed as I 615 nm / I 550 nm = A *[LFX] 2 + B *[LFX] + C . It is used to quantitatively detect the LFX concentrations in fetal calf serum (FCS) and tablets sold in pharmacy. Filter paper strips bearing 1 can be used to qualitatively detect LFX by a color change to red under a UV lamp. 1 and its hybrid with sodium alginate (SA), 1 @SA, display potential applications in the qualitative detection of LFX in FCS and the medicine. The limit of detection of 1 to LFX is as low as 2.1 × 10 -2 nM.

Meloxicam (MLX) is a novel nonsteroidal anti-inflammatory drug, but on the other hand, it has become one of the common microcontaminants in surface waters and sewage. Herein, we report the preparation of a ternary-metal Zn(II)-Cd(II)-Eu(III) nanocluster 1 for the response of MLX through the enhancement of lanthanide luminescence. The luminescence sensing behavior of 1 is expressed by the equation I 615nm = 3060 × [MLX] + 46,604, which can be used in the quantitative analysis of MLX concentrations in meloxicam dispersible tablets. Filter paper strips bearing 1 can be used to qualitatively detect MLX by a color change to red under a UV lamp. The luminescence response time is no more than five s, and the detection limit is as low as 2.31 × 10 -2 nM.

A nine-metal Zn(II)-Eu(III) nanoring 1 with a diameter of about 2.3 nm was constructed by the use of a long-chain Schiff base ligand. It shows a luminescence response to neopterin (Neo) through the enhancement of lanthanide emission with high selectivity and sensitivity, which can be used to quantitatively analyze the concentrations of Neo in fetal calf serum and urine. The luminescence sensing of 1 to Neo is temperature-dependent, and it displays more obvious response behavior at lower temperatures. Filter paper strips bearing 1 can be used to qualitatively detect Neo by the color change from chartreuse to red under a UV lamp. The limit of detection is as low as 3.77 × 10 -2 nM.

A near-infrared luminescent Cd(II)-Nd(III) nanocluster 1 (molecular dimensions of 1.0 nm × 2.2 nm × 2.2 nm) was obtained using a Schiff base ligand. It can be used as a sensor for the wavelength-dependent detection of rutin even in the presence of other interference, which can be expressed by the third-order equation I Ex470 nm / I Ex395 nm = A [Rut] 3 + B [Rut] 2 + C [Rut] + D . 1 is used to analyze the Rut concentrations quantitatively in CH 3 CN and fetal calf serum (FCS). For the determination of Rut concentrations in FCS, the ranges of recovery and relative standard deviations are 99.06-104.70% and 2.30-4.15%, respectively.

A near-IR-luminescent octanuclear Yb(III) complex 1 was constructed from a new dodecadentate Schiff base ligand, which is used in the rapid and reliable wavelength-dependent detection of aloe emodin (AE) with high sensitivity even in the presence of other interferences.

An interesting 48-metal Zn(II)-Yb(III) nanocluster ( 1 ) with a size of about 1.3 × 2.8 × 3.1 nm was constructed by carbonate templates from a Schiff base ligand. It exhibits ligand-centered emission and near-infrared (NIR) luminescence of Yb(III), which are used in the dual-emissive detection of rutin (Rut) with high sensitivity even in the presence of other interferences. The response behavior can be expressed by the second-order equation I 980 nm / I 510 nm = A *[Rut] 2 + B *[Rut] + C , and the limits of detection to Rut for the emissions of 1 are 2.23 μM and 0.20 nM.

A Cd(II)-Tb(III) nanocluster {[Cd 10 Tb 9 L 8 (OH) 16 (OAc) 23 (H 2 O) 3 ][Cd 10 Tb 9 L 8 (OH) 16 (OAc) 23 (H 2 O) 4 ]}·3H 2 O ( 1 ), which contains two crystallographically independent components, was constructed from a tridentate ligand (HL, 3-ethoxysalicylaldehyde). It exhibits rapid and reliable excitation wavelength-dependent luminescence response to 2,6-dipicolinic acid (DPA) [limit of detection = 0.23 nM], which is not influenced by aromatic carboxylates, amino acids, and ions. The test papers of 1 can be used to check DPA in solution. The equation I Ex272nm / I Ex329nm = 0.0109 × [DPA]2 + 0.106 × [DPA] + 2.39 of 1 for the luminescence response could be used to quantitatively measure the concentration of DPA in tap water. 1 displays rapid and stable luminescence response to DPA, with the sensing times shorter than 5 s and no changes for the lanthanide luminescence over 24 h.

A tubelike Zn(II)-Yb(III) cluster, [Zn 6 Yb 5 L 5 (HL)(NO 3 ) 4 (DMF) 6 (EtOH) 4 (H 2 O) 4 ] ( 1 ; DMF = N , N -dimethylformamide and EtOH = ethanol; molecular size 1.5 × 1.8 × 2.9 nm), was synthesized from a new long-chain Schiff base ligand. 1 exhibits a regulatable near-IR-luminescent response to nitrofuran antibiotics (NFAs) and fluoroquinolones with high sensitivity, which is not influenced by other antibiotics. The quenching constants of NFAs and fluoroquinolones range from 0.55 × 10 4 to 8.8 × 10 4 M -1 , and the detection limits of 1 to them are from 4.2 × 10 -4 to 2.6 × 10 -5 M. It also shows a luminescent response to real antibiotic drugs containing NFAs and fluoroquinolones.

Two NIR luminescent Zn(II)/Cd(II)-Yb(III) complexes were obtained by the use of a Schiff base ligand with a binaphthyl backbone. Cd(II)-Yb(III) complex 2 has a triangular structure and exhibits interesting luminescent sensing activity to antibiotics, in particular to ciprofloxacin (CPFX) and norfloxacin (NFX) due to the inner filter effect. The limits of the detection of 2 to CPFX and NFX are 0.18 and 0.36 μM, respectively, and the fluorescence sensitivity is not changed with the existence of other antibiotics tested in this study.

Two d-4f complexes [Zn 2 NdL 2 (OAc) 2 ]·OH ( 1 ) and [Cd 3 Sm 3 L 3 (OAc) 6 (OH) 3 ] ( 2 ) with a designed Schiff base ligand N , N '-bis(3-methoxysalicylidene)(binaphthyl)-1,4-diamine (H 2 L) were synthesized. The Schiff base ligands coordinate with metal ions by μ 2 (η 1 :η 2 :η 1 :η 1 :η 2 :η 1 ) and μ 2 (η 1 :η 2 :η 1 :η 1 :η 2 :η 1 ) modes in the complexes, which show typical lanthanide emissions. The triangular Cd-Sm complex 2 shows both visible and NIR luminescent responses to nitrobenzene explosive 2,4,6-trinitrophenol (PA).

One 18-metal Nd(III) nanoring, [Nd 18 (L 1 ) 8 (HL 2 ) 2 (OAc) 20 (MeOH) 8 (EtOH) 6 (H 2 O) 4 ]·2(MeOH)·6(H 2 O) ( 1 ), was constructed by the use of a hexadentate Schiff base ligand. For 1 , the near-infrared (NIR) luminescence of Nd(III) was detected under the excitation of absorption band at 371 nm. The study of luminescent sensing properties exhibits that, even with the existence of other antibiotics, this Nd(III) nanoring displays high sensitivity and selectivity to nitrofuran antibiotics (NFAs). The luminescence quenching constants and limits of detection of 1 to NFAs are found to be 1.4 × 10 4 to 3.5 × 10 4 M -1 and 0.9-2.2 μM, respectively.

One 12-metal Cd(II)-Yb(III) nanoring, [Cd 8 Yb 4 L 8 (OAc) 8 ]·4OH ( 1 ), with a size of 1.2 × 2.8 × 2.8 nm was obtained from a designed flexible salen-type ligand that has eight coordination sites (O and N atoms). The near-IR emission of Yb(III) at 983 nm was detected upon the excitation of ligand-central absorption at 386 nm. This Cd(II)-Yb(III) nanoring exhibits high sensitivity to nitrofuran antibiotics (NFAs) even in the presence of other antibiotics. The quenching constants and limits of detection of NFAs are 2.5 × 10 4 -4.5 × 10 4 M -1 and 1.5-2.8 μM, respectively.

One Nd(III) complex [Nd 3 L 3 (OAc) 3 ] ( 1 ) was synthesized from a conjugate Schiff base ligand H 2 L. It shows a chiral "triple-decker" structure (1.1 × 1.2 × 1.8 nm) with Nd(III) ions sandwiched between the Schiff base ligands. 1 exhibits NIR Nd(III) luminescence, and the LMET efficiency is calculated to be 13.8%. It displays high luminescence sensitivity and selectivity to Co(II). The K SV value and LOD of 1 to Co(II) are 9.96 × 10 4 M -1 and 0.97 μM, respectively.

Two series of 4d-4f clusters [Ln8Cd24L12(OAc)48] and [Ln6Cd18L9Cl8(10)(OAc)28(26)] (Ln = Nd, Gd, Er, and Yb) with novel drum-like structures were prepared using a flexible Schiff base ligand. Their NIR luminescence properties were determined.

Developing selectively targeted and heat-responsive nanocarriers holds paramount promises in chemotherapy. We show that this can be achieved by designing liposomes combining cationic charged and thermosensitive lipids in the bilayer. We demonstrated, using flow cytometry, live cell imaging, and intravital optical imaging, that cationic thermosensitive liposomes specifically target angiogenic endothelial and tumor cells. Application of mild hyperthermia led to a rapid content release extra- and intracellularly in two crucial cell types in a solid tumor.