Novel Ca_(8)CuRE(PO_(4))_(7)where RE^(3+)=Eu^(3+),Tb^(3+),Dy^(3+),Ho^(3+)and Er^(3+)were synthesized by a solid-state method in air.The structures of the samples were characterized by powder X-ray diffraction using Rietveld refinement to determine the occupation of crystal sites.The samples are found to have a centrosymmetric structure with space group R3c,as shown by dielectric measurements.These synthesized Ca_(8)CuRE(PO_(4))_(7)samples have multifunctional properties.The Cu^(2+)ions provide antibacterial properties,while the rare earth elements ions exhibit luminescence properties,and theβ-Ca_3(PO_(4))_(2)-type host is biocompatible.The photoluminescence properties of RE^(3+)ions were studied and compared with other simmilar Ca_(8)MRE(PO_(4))_(7)phosphates,where M is a divalent metal.The photoluminescence intensity quenching in terms of energy transfer from RE^(3+)to Cu^(2+)is disscused.The bioactive properties were studied in relation to antibacterial activity against E.coli and S.aureus.All syntesized Ca_(8)CuRE(PO_(4))_(7)samples demonstrate very high and stable inhibition of bacteria growth.The correlation between crystal structure and properties is discussed.By combining multiple approaches to the directio nal design of such materials,several important properties within a single chemical compound to achieve biovisualization and bioactive properties simultaneously can be combined.
Ivan V.NikiforovEkaterina V.IliinaBogdan I.LazoryakSergey M.AksenovPavel V.SlukinDina V.Deyneko
Developing fluorescent sensors for small-molecule phosphates offers opportunities in optically detecting biorelevant reactions and events.However,it remains elusive how to identify phosphates from other anions,such as carboxylates and sulfates,because current synthetic phosphate receptors lack selectivity.Here we report the construction of a multicolor fluorescent sensor that can identify phosphates from other analogous anions.The key design principle is to take advantage of the highly sensitive conformation-dependent emissive wavelength of diphenyl-9,14-dihydrodibenzo[a,c]phenazine fluorophores to sense the minor structural differences between phosphates and other anions,for example,sulfates and carboxylates.The effect of structural factors such as spacer length and urea versus thiourea has been investigated by comparing the optical properties and binding affinities with the phosphate receptors.This strategy provides a simple and robust fluorescent sensing solution to optically analyze small-molecule phosphates with antiinterference performance.
This study presents a facile and rapid method for synthesizing novel Layered Double Hydroxide(LDH)nanoflakes,exploring their application as a photocatalyst,and investigating the influence of condensed phosphates'geometric linearity on their photocatalytic properties.Herein,the Mg O film,obtained by plasma electrolysis of AZ31 Mg alloys,was modified by growing an LDH film,which was further functionalized using cyclic sodium hexametaphosphate(CP)and linear sodium tripolyphosphate(LP).CP acted as an enhancer for flake spacing within the LDH structure,while LP changed flake dispersion and orientation.Consequently,CP@LDH demonstrated exceptional efficiency in heterogeneous photocatalysis,effectively degrading organic dyes like Methylene blue(MB),Congo red(CR),and Methyl orange(MO).The unique cyclic structure of CP likely enhances surface reactions and improves the catalyst's interaction with dye molecules.Furthermore,the condensed phosphate structure contributes to a higher surface area and reactivity in CP@LDH,leading to its superior photocatalytic performance compared to LP@LDH.Specifically,LP@LDH demonstrated notable degradation efficiencies of 93.02%,92.89%,and 88.81%for MB,MO,and CR respectively,over a 40 min duration.The highest degradation efficiencies were observed in the case of the CP@LDH sample,reporting 99.99%for MB,98.88%for CR,and 99.70%for MO.This underscores the potential of CP@LDH as a highly effective photocatalyst for organic dye degradation,offering promising prospects for environmental remediation and water detoxification applications.
为改善低盐(1g/100mLNaCl)环境中肌原纤维蛋白的功能特性,研究不同添加量的焦磷酸钠(tetrasodium pyrophosphate,TSPP)、三聚磷酸钠(sodium tripolyphosphate,STPP)、六偏磷酸钠(sodium hexametaphosphate,SHMP)对白鲢鱼肌原纤维蛋白结构和功能特性的影响。结果表明:低盐条件下,随着磷酸盐添加量的增加,肌原纤维蛋白的溶解度、表面疏水性、乳化性均呈上升趋势;3种磷酸盐均使肌原纤维蛋白引入磷酸基团;添加0.2~0.5 g/100 mL STPP能够降低肌原纤维蛋白热解速率,提升蛋白质热稳定性,其中0.4 g/100 mL STPP修饰的蛋白质磷酸化程度最大,此时大量的磷酸根基团与肌原纤维蛋白结合;TSPP和STPP更有利于蛋白质的聚集,而SHMP磷酸化的蛋白质更稳定。综上,0.4 g/100 mL STPP对低盐条件下肌原纤维蛋白功能特性具有更好的改善作用。