Xin Li,Xiangheng Niu,Peng Liu,Xuechao Xu,Dan Du,Yuehe Lin
Phosphate ion (Pi) is an inorganic anion widely distributed and commonly regarded as a significant indicator of water eutrophication, and thus it is urgent to develop convenient, cost-effective and reliable analytical approaches for the monitoring of Pi for water quality control. In this work, we propose the high-performance dual-channel ratiometric colorimetric sensing of Pi based on the analyte-triggered differential oxidase-mimicking activity changes of oxidized Ce-Zr bimetal-organic frameworks (oxidized UiO-66(Ce/Zr)). By integrating two types of metal nodes with different functions into one framework structure, the proposed oxidized UiO-66(Ce/Zr) not only exhibits excellent activity to catalyze the chromogenic oxidation of both 3,3′,5,5′-tetramethylbenzidine (TMB) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) due to oxidase-like active Ce 4+ /Ce 3+ sites but also provides main Zr 4+ sites to specifically recognize Pi. When Pi is in presence, it is rapidly adsorbed onto oxidized UiO-66(Ce/Zr) and changes the surface chemistry of the latter, leading to differential enzyme-like activity changes towards the two chromogenic substrates TMB and ABTS. Based on this finding, a dual-channel ratiometric colorimetric method was established for the sensitive determination of Pi. Compared to conventional single-signal colorimetric sensors, our method offered a widened linear detection scope from 3.3 to 666.7 μM. Also, robust and accurate analysis of Pi in various water matrices was demonstrated, indicating our method’s great potential in practical applications.
Zhifang Wu,Xiaokan Wang,Zhe Wang,Changyu Shao,Xiaoting Jin,Leiqing Zhang,Haihua Pan,Ruikang Tang,Baiping Fu
Lab biomineralization should be carried out in an actual clinical practice. This study evaluated self-etch adhesive as a carrier for amorphous calcium phosphate (ACP) nanoprecursors to continuously deliver biomimetic remineralization of self-assembly type I collagen and demineralized dentin. Si-containing ACP particles (Si-ACP) stabilized with polyaspartic acid (PAsp) were synthesized and characterized by transmission electron microscopy (TEM), scanning electron microscopy–energy-dispersive X-ray spectroscopy, Fourier transform infrared analysis, X-ray powder diffractometry, and X-ray phototelectron spectroscopy. The biomimetic remineralization of single-layer reconstituted type I collagen fibrils and demineralized dentin was analyzed by using two one-bottle self-etch dentin adhesives (Clearfil S3 Bond (S3), Kurraray-Noritake; Adper Easy One (AEO), 3 M ESPE) as a carrier loaded (or not, in the case of the control) with 25 wt % of Si-ACP particles. In vitro cytotoxicity assessed by the Cell Counting Kit-8 indicated that the Si-ACP particles had no adverse effect on cell viability. The capacity for Ca and P ions release from cured Si-ACP-containing adhesives (S3, AEO) was evaluated by inductively coupled plasma-atomic emission spectrometry, revealing the successively increasing release of Ca and P ions for 28 days. The intra- and extrafibrillar remineralization of type I collagen and demineralized dentin was confirmed by TEM and selected-area electron diffraction when the adhesives were used as a carrier loaded with Si-ACP particles. Therefore, we propose self-etch adhesive as a novel carrier for ACP nanoprecursors to continuously deliver biomimetic remineralization.
危险品化学品经营许可证（带存储）