Yb-TCPP metal-organic framework as fluorescence sensor for detecting tetracycline in milk.

Developing effective means for detecting contamination in milk during production, processing, and storage is both important and challenging. Tetracycline (TC), due to its use in treating animal infections, is among the most prevalent organic pollutants in milk, posing potential and significant threats to human health. However, efficient and in situ monitoring of TC remains lacking. Nevertheless, we have successfully developed a highly sensitive and selective fluorescence method for detecting TC in milk using a metal-organic framework material made from Yb-TCPP (ytterbium-tetra(4-carboxyphenyl)porphyrin). The calculated Stern-Volmer constant (KSV) was 12,310.88 M-1, and the detection limit was 2.44 × 10-6 M, surpassing previous reports. Crucially, Yb-TCPP fluoresces in the near-infrared region, promising its development into a specific fluorescence detection product for practical TC detection in milk, offering potential application value.

1-Bromo-4-methyl-2-nitro-benzene.

In the title compound, C(7)H(6)BrNO(2), the dihedral angle between the nitro group and the phenyl ring is 14.9 (11)°.

Isopropyl-triphenyl-phospho-nium bromide monohydrate.

In the title water-solvated salt, C(21)H(22)P(+)·Br(-)·H(2)O, the ionic components are linked by short C-H⋯Br contacts along the a-axis direction. The two half occupied water mol-ecules are connected to each other by strong O-H⋯O hydrogen bonds and they are also linked to the bromide anion by short O-H⋯Br contacts.

An economic method for synthesis of highly ordered porous silica.

We report an economic method for synthesis of highly ordered silica with a mixing surfactant system containing short-chain cationic surfactant (decyltrimethyl ammonium bromide, denoted C10TMAB) and short-chain anionic surfactant (sodium octyl sulfate, denoted SOS) as the templating agents. Highly ordered supermicroporous silica was synthesized by judiciously chosen mixing ratio of surfactants. The samples were characterized by small-angle X-ray diffraction, transmission electron microscopy, and N2 adsorption-desorption. The results showed that the pore structure of the resulting silica belongs to the two-dimensional hexagonal structure (space group 2D-p6mm) with a pore size of ca. 2.2nm. Moreover, the method proposed herein is expected to facilitate the synthesis of not only porous silicas but also materials with other framework compositions.