Na-Ln Heterometallic Coordination Polymers: Structure Modulation by Na+ Concentration and Efficient Detection to Tetracycline Antibiotics and 4-(Phenylazo)aniline.

On the basis of the lanthanide metalloligand [Ln(ODA)3]3- (H2ODA = oxydiacetic acid), three new Na-Ln heterometallic coordination polymers, [Ln(ODA)3Na2]n [Ln = Eu (1) and Gd (2)] and [Tb(ODA)3Na3(H2O)2]n (3), had been assembled by adjusting the concentration of Na+ ions in the reaction system. The investigations of fluorescence sensing showed that 1 could be a ratiometric probe to detect tetracycline (TC) and oxytetracycline (OTC) with high sensitivity and low detection limits, 71.92 ppb for the former and 45.54 ppb for the latter, and 3 could selectively sense 4-(phenylazo)aniline through the turn-off pathway with 14.59 ppb of detection limits. Moreover, the competing and circulating experiments indicated that both 1 and 3 had satisfactory antiinterference and recyclability for the corresponding analytes. All of these results implied that 1 and 3 should be potential fluorescent sensors for the detection of TC/OTC and 4-(phenylazo)aniline, and the possible sensing mechanism had also been discussed in depth.

Loading drugs into liposomes by temperature up-down cycle procedure with controllable results fitting prediction by mathematical and thermodynamic process.

Liposomes are a useful carrier for delivering drugs but rarely make a poorly water-soluble drug (PWSD) realize its therapeutic potential. A key barrier lies in that, by conventional methods, PWSD is mainly loaded just in liposome bilayer membranes, which rarely provide sufficient room to accommodate drugs satisfying clinical therapy. In this investigation, a novel procedure of temperature up-down cycle (TUDC) was developed for loading PWSDs into the liposome interiors instead of bilayer membranes to hold enough agents. In particular, the TUDC procedure renders PWSDs such as curcumin (Cur) entrapment purposely controllable, as evidenced by the encapsulation efficiency (EE) of Cur varies nearly from 0% to 100% in response to changes the determinant factors of the procedure. In addition, several mathematical equations that could calculate the loading efficiency by TUDC were established and proved, when combined with thermodynamic process, able to successfully predict the loading results through including thermodynamic parameters, such as temperature and deduced drug solubility, thus remarkably cutting down the laborious experiments and enhancing liposome development efficiency. Cryo-TEM, SAXS, XRD and DSC tests proved that TUDC is feasible to load a PWSD into PEG-liposomes but rendering the drug in the amorphous state. Thus, the novel TUDC procedure and the established mathematical and thermodynamic process may provide a useful tool to promote the development of liposome products.

Ultrasmall Hyperbranched Semiconducting Polymer Nanoparticles with Different Radioisotopes Labeling for Cancer Theranostics.

Exploiting ultrasmall nanoparticles as multifunctional nanocarriers labeled with different radionuclides for tumor theranostics has attracted great attention in past few years. Herein, we develop multifunctional nanocarriers based on ultrasmall hyperbranched semiconducting polymer (HSP) nanoparticles for different radionuclides including technetium-99m (99mTc), iodine-131 (131I), and iodine-125 (125I) labeling. SPECT imaging of 99mTc labeled PEGylated HSP nanoparticles (HSP-PEG) exhibit a prominent accumulation in two-independent tumor models including subcutaneously xenograft and patient derived xenograft model. Impressively, 5,6-dimethylxanthenone-4-acetic acid (DMXAA), as tumor-vascular disrupting agent (VDA), significantly improves the tumor accumulation of 131I labeled HSP-PEG nanoparticles, further leading to the excellent inhibition of tumor growth after intravenous injection. More importantly, SPECT imaging of 125I labeled HSP-PEG indicates that ultrasmall HSP-PEG nanoparticles could be slowly excreted from the body of a mouse through urine and feces in 1 week and cause no obvious toxicity to treated mice from blood analysis and histology examinations. Our finding from the different independent tumor models SPECT imaging shows that HSP-PEG nanoparticles may act as multifunctional nanocarriers to deliver different radionuclides for monitoring the in vivo behaviors of nanoparticles and cancer theranostics, which will provide a strategy for cancer treatment.