A simple method for the preparation of core-shell micro/nanostructured magnetic molecularly imprinted polymers (MIPs) for protein recognition is described. Magnetic MIPs were synthesized by copolymering gamma-aminopropyltrimethoxysilane and tetraethyl orthosilicate at the surface of Fe(3)O(4) nanospheres, which were directly covalently bound with template molecule, bovine hemoglobin (BHb), through imine bond. Transmission electron microscopy and scanning electron microscopy images showed that the Fe(3)O(4) nanospheres with diameter about 50-150 nm were coated with the MIPs layer with average thickness about 10 nm, which enabled the magnetic MIPs to have a sensitive and fast magnetic response. The proximity between the thickness of MIPs layer and the spatial size of BHb indicated that the imprinted sites almost situated at the surface of magnetic MIPs, leading a rapid adsorption saturation within 1 h. And the adsorption amounts of magnetic MIPs toward BHb were estimated to be 10.52 mg/g at pH 6.5, which was 4.6 times higher than that of magnetic nonmolecularly imprinted polymers. Meanwhile, the result of selective test showed that the magnetic MIPs had an excellent recognition capacity to BHb compared to the other nontemplate proteins. Except for the spatial size complementary between BHb and the binding sites in magnetic MIPs, the electrostatic interaction also was proven to be an important factor for recognizing the imprinting molecule.

Spheres-like coordination polymer architectures in submicro regimes have been synthesized from the hydrothermal reaction of transition metal ions and 3,5-bis(pyridin-3-ylmethylamino)benzoic acid (L1). The size of the final coordination polymer was dependent on the concentrations of reactants. Scanning electron microscopy studies monitored at numerous stages of growth reveal that coordination-induced morphology changes from uncoordinated flowerlike ligands to sphere-like coordination polymer particles. Moreover, variations of luminescent and antibacterial profiles are associated with coordination environments or the size of as-obtained coordination polymer samples. In addition, the newly synthesized Cu-based polymer particles may act as novel metal-based anticancer drugs in the future because of their potent in vitro anticancer activities against three chosen cancer lines MCF-7, HeLa, and NCI-H446.

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Single-crystalline EuF(3) hexagonal microdisks with hollow interior were fabricated to serve as a background-free matrix for analysis of small molecules and polyethylene glycols (PEGs) by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The long-lived excited state of europium ions can transfer energy to high-energy vibrations of organic molecules, which provides the potential technological application in MALDI-TOF-MS analysis of small molecules and PEGs. The efficiency of the hollow microdisks as a novel matrix of low molecular weight compounds was verified by analysis of small peptide, amino acid, organic compounds, and hydroxypropyl beta-cyclodextrin (HP-beta-CD). The advantage of this matrix in comparison with alpha-cyano-4-hydroxycinnamic acid (CHCA) and 2,5-dihydroxybenzoic acid (DHB) was demonstrated by MALDI-TOF-MS analysis of an amino acid mixture and a peptide mixture. This matrix is successfully used for analysis of PEGs (PEG 2000, PEG 4000, PEG 8000, PEG 15000, and PEG 30000), suggesting a potential for monitoring reactions and for synthetic polymer quality control. The upper limit of detectable mass range was approximately 35,000 Da (PEG 30000). It is believed that this work will not only offer a new technique for high-speed analysis of small molecules and PEGs but also open a new field for applications of rare earth fluorides.