Amine-grafted on lanthanide metal-organic frameworks:Three solid base catalysts for Knoevenagel condensation reaction

A post-synthetic modification strategy has been used to prepare three solid base catalysts, including Er（btc）（ED）075（H2O）0.25 （2, btc = 1,3,5-benzenetricarboxylates, ED = 1,2-ethanediamine）, Er（btc）（PP）0.55（H20）0.45 （3, PP = piperazine）, and Er（btc）（DABCO）0.15（H2O）0.85 （4, DABCO = 1,4- diazabicyclo[2.2.2]octane）, by grafting three different diamines onto the coordinatively unsaturated Er（III） ions into the channels of the desolvated lanthanide metal-organic framework （Er（otc））. The resulting metal-organic frameworks were characterized by elemental analysis, thermogravimetric analysis, powder X-ray diffraction, and N2 adsorption. Based on its higher loading ratio of the diamine, as well as its greater stability and porosity, catalyst 2 exhibited higher catalytic activity and reusability than catalysts 3 and 4- for the Knoevenagel condensation reaction. The catalytic mechanism of 2 has also been investigated using size-selective catalysis tests.

An 8-Connected Chiral Lanthanide Metal-organic Framework Constructed from Naturally Camphoric Acid:Crystal Structure,Vibrational Circular Dichroism Spectroscopy and Second-order Nonlinear Optical Effect

A chiral lanthanide metal-organic framework based on enantiopure camphoric acid （D-H2cam）, [Nd3（D-cam）8（H2O）4Cl]n （1）, has been synthesized and characterized by single-crystal X-ray structural analysis, elemental analysis, IR, thermal gravimetric, and X-ray powder diffraction. Crystal data for the title compound are as follows： orthorhombic system, space group P212121 with a = 13.8287（7）, b = 14.0715（7）, c = 25.7403（12） A^°, V = 5008.8（4） A^°3, Mr = 1333.08, Z = 4, F（000） = 2644, Dc = 1.768 g/cm^3, μ（MoKα） = 3.189 mm^-1, the final R = 0.0351 and wR = 0.0814 （I 〉 2σ（I））. Compound 1 displays an 8-connected bcu topology 3D framework and hydrogen-bonding interactions stabilize the solid-state structure. The vibrational circular dichroism （VCD） spectrum and second-order nonlinear optical effect of compound 1 have been studied in the solid state.

A 3-D Supramolecular Framework with Open Channels Constructed from Lanthanide Ions and Mixed Ligands

A 3-D supramolecular framework, [Er（pybz）2（Hnds）（H2O）2]·H2O （1, Hpybz = 4- pyridin-4-yl-benzoic acid, H2nds = naphthalene-1,5-disulfonic acid）, based on lanthanide ions and mixed ligands has been hydrothermally synthesized. The structure was determined by single-crystal X-ray diffraction and further characterized by IR, elemental analysis and thermogravimetric analysis. Compound 1 crystallizes in the monoclinic system, space group P21/n with a = 9.849（2）, b = 22.526（5）, c = 17.167（4） A, β =105.461（4）° and V = 3670.9（2） A^3. In 1, two seven-coordinated Er^3＋ ions are bridged by two pybz^- ligands to form a dimeric [Er2（COO）2] unit, which is further orderly linked by carboxyl of pybz^-ligand to obtain a 1-D chain running along the a axis. Interestingly, significant H-bonding and π-π stacking interactions link the neighboring parallel chains leading to a 3-D supramolecular network structure which displays 1-D rhombus open channels （17.2A× 22.5A）.

Structural Characterization and Proton-conductive Property of a Lanthanide Metal-organic Framework Assembled from 1,2,4,5-Benzenetetracarboxylic Acid and Piperazine

The reaction of Pr（Ⅲ） salt with 1,2,4,5-benzenetetracarboxylic acid（H4betc） and piperazine（pip） yielded a lanthanide metal-organic framework {[Pr（betc）（H2O）2]（H2pip）0.5}n（1）under hydrothermal conditions. Compound 1 was characterized by single-crystal X-ray structural analysis, elemental analysis, IR, X-ray powder diffraction, and thermal gravimetric. Compound 1crystallizes in monoclinic, space group P21/n with a = 11.023（5）, b = 11.109（5）, c = 11.456（5） A, β = 110.065（5）°, V = 1317.7（9） A3, Mr = 471.14, Z = 4, F（000） = 920, Dc = 2.375 g/cm^3, μ（Mo Kα） = 3.761 mm-1, the final R = 0.0286 and w R = 0.0821（I 〉 2σ（I））. Compound 1 exhibits a 2D network with（4, 4） topology, and a 3D supramolecular framework formed by hydrogen-bonding interactions. The proton conductivity of compound 1 has been investigated at ~97% relative humidity and different temperature.

Hydrothermal Synthesis of Two 3D Lanthanide(Ⅲ) Organometallic Polymers in the 3,5-Pyridinedicarboxylate System with Different Coordination Architecture

Two coordination polymers of lanthanide complexes [（Dy）2（3,5-PDA）3（H2O）2]n 1 and [（Pr）2（3,5-PDA）3（H2O）3]n 2 （3,5-PDA = pyridine-3,5-dicarboxylate） have been synthesized under hydrothermal conditions. The prepared compounds were characterized by elemental analysis, IR and TG analyses and single-crystal X-ray structure determination. Complex 1 crystallizes in monoclinic, space group C2/c with a = 14.104（2）, b = 11.1129（16）, c = 15.086（2） , β = 92.138（2）o, V = 2362.8（6） 3, Z = 4, C21H13Dy2N3O14, Mr = 856.34, Dc = 2.407 g·cm-3, F（000） = 1616, μ（MoKα） = 6.359 mm-1, the final R = 0.0422 and wR = 0.1016 for 2000 observed reflections with I 2σ（I）. Complex 2 crystallizes in triclinic, space group P with a = 8.9441（13）, b = 9.3959（14）, c = 14.625（2） , α = 98.065（2）, β = 95.481（2）, γ = 104.9130（10）o, V = 1164.7（3） 3, Z = 2, C21H15Pr2N3O15, Mr = 831.18, Dc = 2.370 g·cm-3, F（000） = 800, μ（MoKα） = 4.224 mm-1, the final R = 0.0355 and wR = 0.0731 for 4092 observed reflections with I 2σ（I）. These polymers are constructed from the 3,5-PDA ligand but they exhibit different kinds of metal-organic framework structures. Complexes 1 and 2 are constructed from M-C-O zigzag corner-linked chains （M = Dy and Pr）. In 1, the chains are composed of 8-coordinated DyⅢ centers, while the chains are made up of 8- and 9-coordinated PrIII centers in complex 2. These chains are cross-linked to each other by the pyridine rings of 3,5-PDA ligands, generating three-dimensional architectures. The magnetic behavior of compound 1 has been investigated, showing it exhibits antiferromagnetic interactions among the DyⅢ ions.

Removal of organic pollutants by lanthanide-doped MIL-53(Fe) metal-organic frameworks:Effect of dopant type in magnetite precursor

A series of undoped and lanthanide doped MIL-53(Fe)/Ln-Fe_(3)O_(4)(Ln=La,Nd,or Gd) metal-organic frameworks(MOFs) were prepared by the solvothermal method.All prepared samples were characterized by X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR),Brunauer-Emmett-Teller(BET) measurements,scanning electron microscopy(SEM),and thermal analysis.XRD and FT-IR results ascertain the successful MOF formation for all prepared samples.MIL-53(Fe)/La-Fe_(3)O_(4) has the smallest particle size of 8.6 nm,the largest BET surface area of 54.2 m^(2)/g,and the highest porosity.Undoped and different lanthanide doped MIL-53(Fe) we re employed as sorbents for the removal of methylene blue(MB)dye from aqueous solutions to examine the doping benefit and the effect of the dopant size on the sorption performance.Doping causes MOFs to act as pH-independent sorbents,which make it applicable at any condition.Adsorption follows pseudo-second-order kinetic model,and doped sorbents attain equilibrium faster.Langmuir isotherms are followed,except for MIL-53(Fe)/La-Fe_(3)O_(4).The adsorption capacity increases with increasing the dopant ion size,100.5 mg/g for La-doped MOF,which is about four times higher than that of undoped MOF.The adsorption mechanism involves chemical interactions between Lewis acid in magnetite MIL-53(Fe) series and Lewis base in MB.

基于2,5-二溴对苯二羧酸配体的镧系金属有机骨架的合成、结构及性质

采用溶剂热法,以2,5-二溴对苯二甲酸(H_(2)L)为配体,分别与六水合硝酸钕、六水合硝酸钆反应合成了_(2)种镧系金属有机骨架(MOFs):{[Nd_(2)(L)_(3)(DMF)_(2)(H_(2)O)_(2)]·_(2)DMF}n(1)和{[Gd_(2)(L)_(3)(DMF)_(2)(H_(2)O)_(2)]·2DMF}n(_(2))。通过单晶X射线衍射、粉末X射线衍射、红外光谱、元素分析、荧光光谱、热重分析等测试方法对其进行了结构表征与性质研究。结果表明,2个配合物均是以稀土离子为金属节点,与配体相互连接,形成无限延伸的三维网状结构。

高灵敏、多响应的镧系金属有机骨架的设计、合成和荧光传感性能

基于5-(3,4-二羧基苯氧基)间苯二甲酸(H_(4)dppa)配体,通过水热法设计并合成了2种镧系金属有机骨架(Ln-MOFs):{(dima)[Dy(dppa)(H_(2)O)_(2)]·2.5H_(2)O}n(Dy-MOF)和{(dima)[Eu(dppa)(H_(2)O)_(2)]·1.5H_(2)O}n(Eu-MOF)(dima=二甲胺阳离子)。并用元素分析、红外光谱、单晶X射线衍射等对其进行了结构表征。2种Ln-MOFs为异质同构的二维网状结构,相邻的二维网络通过氢键作用进一步形成三维超分子网络结构。荧光分析表明Dy-MOF和Eu-MOF在室温下具有优良的荧光性能,而且Dy-MOF还具有优异的荧光传感性能,可高效、高灵敏检测多种水中污染物:苯胺(ANI)、硝基苯(NB)、四环素(TC)、嘧霉胺(PTH)以及色氨酸(Trp)。此外还探究了Dy-MOF检测污染物时的荧光淬灭机理。

基于镧系金属-有机骨架材料的比率型荧光探针研究进展

荧光探针能够快速、可靠的识别目标物,因此备受人们关注。与传统单发射中心型荧光探针相比,比率型荧光探针具有更高的灵敏度、高可靠性及可视化传感等优点。镧系金属-有机框架物(Ln-MOFs)具有优异的发光性质,在荧光传感、生物成像等方面具有广阔应用前景。通过合理选择镧系金属离子、有机配体及客体分子可以构筑具有优异发光性能的Ln-MOFs基双发射比率型荧光探针。对Ln-MOFs基双发射比率型荧光探针的构建方法、荧光传感机理及应用领域的最新进展进行综述,并对其未来发展进行了展望,以期为构筑Ln-MOFs基双发射比率型荧光探针提供借鉴。

不同配体结构的镧基MOF高效吸附刚果红染料

文章采用六水合硝酸镧作为金属离子源,分别与对苯二甲酸(BDC)、均苯三甲酸(BTC)、均苯四甲酸(PMA)以及4,4'-联苯二甲酸(BDA)4种不同的有机配体结合,通过溶剂热法成功制备了一系列镧基金属有机框架(La-MOF)。通过扫描电子显微镜(SEM)、X射线衍射(XRD)、X射线光电子能谱(XPS)以及比表面积与孔隙度分析(BET)等表征手段,研究了不同有机配体所合成La-MOF的物理化学性质。此外,通过批量实验探讨了pH、温度、接触时间以及多次循环对吸附刚果红(CR)性能的影响,并推导了相应的反应机理。结果表明,4种La-MOF的吸附过程均符合准二级动力学模型和Langmuir等温线模型。通过等温线模型拟合,得到4种材料的饱和吸附容量分别为La-BDC(2249.56 mg/g)>La-PMA(1864.40 mg/g)>La-BTC(1632.87 mg/g)>La-BDA(1037.52 mg/g)。综合分析显示,La-BDC具有更佳的综合吸附性能,其吸附机理主要涉及氢键、π-π键作用以及静电相互作用,但其在循环利用性方面表现出一定的不足。

Alkynyl-anchored silver nanoclusters in lanthanide metal-organic framework for luminescent thermometer and CO_(2) cycloaddition

In this study,an alkynyl-modified aromatic dicarboxylic acid bifunctional ligand was selected to construct lanthanide compound{[Eu_(4)(ebdc)_(6)(4,4-bpy)_(0.5)(H_(2)O)_(4.5)]·(C_(2)H_(5)OH)_(1.25)(H_(2)O)}_(n)(Eu-MOF,H_(2)ebdc=5-ethynyl-isophthalic acid,4,4-bpy=4,4-bipyridine,MOF=metal-organic framework),of which the uncoordinated alkynyl group would be used to anchor silver nanoclusters(Ag NCs).The Eu-MOF exhibits double emission peaks,located at 492 and 611 nm,respectively,in which the high-energy blue emission is associated with alkynyl-modified ligand while the low-energy red emission belongs to characteristic emission of Eu3+,indicating that ligands can effectively sensitize Eu3+luminescence.The intensity ratio of the dual emission fluorescence peaks of Eu-MOF displays a good linear relationship with temperature,which realizes the detection function in the low temperature region of 75–275 K,the thermal sensitivity reaches 1.5398%·K^(−1).After anchoring the Ag NCs,the high-energy blue emission is significantly quenched,indicating that the Ag NCs are indeed confined into the framework and interact with the alkynyl group,and thus change the overall electronic distribution.This is the first case of anchoring Ag NCs by a luminescent Eu-MOF and studying nanocluster loading by using spectroscopic properties.In addition,the Ag NCs@Eu-MOF also shows a good catalytic activity for cycloaddition reaction from CO_(2)and epoxides.This study not only provides ideas for exploring the changes in optical properties of luminescent MOFs and Ag NCs caused by confinement effect,but also expands their potential applications in various fields.

Recent Progresses in Lanthanide Metal-Organic Frameworks(Ln-MOFs) as Chemical Sensors for Ions, Antibiotics and Amino Acids

Various ions and antibiotics,widely used in industry and clinical medicine,respectively,are massively discharged to atmosphere and water,resulting in severe pollutions on environment and potential threats to human health.Besides,amino acids,the primary substances for the establishment of proteins,cells and tissues,are crucial to human health.Therefore,seeking effective and practicable materials to detect aforesaid analytes is vitally meaningful.Metal-organic frameworks centered with lanthanide ions(Ln-MOFs),also known as lanthanide coordination polymers,are considered as a charming category of multi-functional hybrid crystalline materials with fascinating structures and incomparable luminescent characteristics.Benefited from their unique merits,Ln-MOFs have been largely developed as excellent luminescent sensors for fast and efficient sensing various analytes.In this review,we aim to introduce some of the recent researches between 2018 to 2022 on Ln-MOFs applied as chemical sensors for ions,antibiotics and amino acids based on luminescent quenching and enhancing effects,and provide an update and summary for the latest progresses in this field.

Crystal Structure,Fe^(3+) Luminescence Sensing and Color Tuning of 2D Lanthanide-metal-organic Frameworks Constructed from Tricarboxylic Acid Ligand

A new lanthanide metal-organic framework (MOF)[Eu(BTB)(phen)(DMF)]·DMF (1,DMF=N,N-dimethylformamide) was synthesized using H_(3)BTB (1,3,5-tri(4-carboxyphenyl)benzene) and phen(1,10-phenanthroline) under solvothermal conditions.The structure of the prepared MOF was characterized by single-crystal X-ray diffraction analyses,elemental analysis,fluorescence spectrum,FT-IR spectroscopy,powder X-ray diffraction and thermogravimetric analyses.The structure of 1 can be viewed as a 3-D supramolecular network,which is formed by the stacking of 2D layers throughπ-πinteraction.The luminescence explorations revealed that 1 possesses favorable selectivity and sensitivity for testing Fe^(3+).Additionally,color tuning was achieved by varying Eu^(3+):Tb^(3+)ratios in the reaction mixtures.

3D metal-organic frameworks based on lanthanide-seamed dimeric pyrogallol[4]arene nanocapsules

Two novel 3D metal-organic frameworks(MOFs)with cds network,{[Me NH_3]_7[Ln_8(Pg C_2)_2(H_2O)_y(HCOO)_7]}_n·x(Solvent)(FJI-Y4,FJI=Fujian Institute,Ln=Gd,y=12;FJI-Y5,Ln=Dy,y=11;Pg C_2=C-ethylpyrogallol[4]arene),based on unprecedented dimeric pyrogallol[4]arene-based Ln_8metal-organic nanocapsule(MONC)supramolecular building blocks and formate linkers,have been prepared under solvothermal conditions.To our best of knowledge,they present not only the first two examples of 3D hierarchical structures constructed from MONCs in metal-pyrogallol[4]arene system,but also the first two examples of MOFs based on lanthanide MONCs.Remarkably,the inner cavity volume of the Ln_8capsule in FJI-Y4 and FJI-Y5 is approximately151?~3,which is larger than those found in previous transition metal-seamed dimeric Pg C_n-based MONCs.Magnetic investigation on FJI-Y4 suggests a significant magnetocaloric effect(23.97 J kg^(-1)K^(-1),ΔH=7 T,2.5 K),while FJI-Y5 exhibits slow relaxation of the magnetization.

Lanthanide-Hypophosphite Frameworks with Guanidinium Guest Showing High Proton Conductivity

Proton-conductive metal-organic frameworks(MOFs)have attracted great attention for their promising application in membrane fuel cells.To explore proton-conductive MOFs with high performance,here we present four lanthanide-hypophosphite frameworks with distinct amine guests.These complexes possess a general formula[AH][Gd_(2)(H_(2)PO_(2))_(7)(AH=protonated amines)].Due to the rich hydrogen bond networks,complex 1 with guanidinium as guest shows high proton conductivity of 1.75×10^(-2) S·cm^(-1) at a relative humidity of 97%(368 K).We also studied the magnetic properties of complex 1 and reveal that the hypophosphite ligand transfers weak antiferromagnetic interactions between Gd^(3+)ions.

Lanthanide-organic frameworks based on terphenyl-tetracarboxylate ligands:syntheses,structures,optical properties and selective sensing of nitro explosives

Three isostructural three-dimensional （3D） lanthanide-based metal-organic frameworks [Ln2L（H2L）（NMP）2]＇H20 （Ln=Sm（l）, Eu （2）, Gd （3）; H4L= 1,1 ＇：4＇, 1 ＂-terphenyl-2＇,4,4＂,5＇-tetracarboxylic acid; NMP=N-methyl-2-pyrrolidone） have been synthesized and structurally characterized. In 1-3, two Ln3＋ ions are doubly-bridged by two oxygen atoms of two carboxylate groups to form the dinuclear Lnz（Oco ）a unit. Each Ln2（Ocoo ）2 unit links with four H2L2 ligands and four L4- ligands to lead to the 3D framework, which can be rationalized as a new trinodal 4,4,8-connected （44.62）（45.6）（412.616） topological network by considering the dinuclear Ln2（Ocoo ）2 units as 8-connected nodes and L4-/H2L2- ligands as planar 4-connected nodes, respectively. 1 and 3 exhibit blue emission originated from the ligand with the emission maximum at 384 nm, while 2 shows intense characteristic red emission of Eu3＋ ions and weak ligand-centered emission. Moreover, 2 has fluorescent quenching response towards the aromatic nitro compounds, especially for the 3,4-dinitrotoluene （3,4-DNT） with the linear Stern-Volmer relationship in the concentration range of 0-1 mM and the quenching constant （Ksv） of 2.084-103 M 1.

Metal-organic frameworks of lanthanide iminodiacetates and tartrates:Synthesis,structural characterization and luminescence properties——Commemorating the 100th anniversary of the birth of Academician Guangxian Xu

Two series of lanthanide-containing metal-organic frameworks(Ln-MOFs)of the general formula{[Ln(HIDA)_(2)H_(2)O]ClO_(4)·H_(2)O}_n(Ln=La(1),Nd(2),Eu(3),Gd(4),Tb(5),Eu:Tb(6);H_(2)IDA=iminodiacetic acid)and[Ln(TT)(HTT)(H_(2)O)_3]_n(Ln=Eu(7),Gd(8),Tb(9),Dy(10),and Eu:Tb(11);H_(2)TT=tartaric acid)were synthesized by reacting Ln(ClO_(4))_3 with iminodiacetic acid and L-tartaric acid,respectively.All compounds were structurally characterized by single-crystal X-ray diffraction.Elemental analyses are co nsistent with the corre sponding crystallographically generated formulas.Mo reover,the luminescence properties of both the single and mixed-lanthanide complexes were studied.Near infrared,red,and green emissions that are characteristic of Nd(Ⅲ),Eu(Ⅲ),and Tb(Ⅲ)are observed for 2,3/7,and 5/9,respectively.For the two mixed-lanthanide complex systems 6 and 11,depending on the relative amount of Eu(Ⅲ)and Tb(Ⅲ),the color of emission can be fine-tuned.It is found that a small amount of Eu(Ⅲ)is adequate for the observation of the most intense transition of Eu(Ⅲ).This is believed to be a result of energy transfer from Tb(Ⅲ)to Eu(Ⅲ)within the same complex-a conclusion supported by the significantly shortened lifetime of Tb(Ⅲ)and the accompanying enhanced lifetime of Eu(Ⅲ)in the mixedlanthanide complex with respect to the corresponding values for the pure Tb(Ⅲ)and Eu(Ⅲ)complexes with the same ligand.

四种同构镧系金属有机框架的合成、结构和荧光传感Fe^(3+)和盐酸环丙沙星

采用溶剂热法,以含氮四羧酸3,5-二(3′,5′-二羧苯)-1H-1,2,4-三唑(H4BDT)为配体,成功合成了4种同构镧系金属有机框架(Ln-MOFs):{[La3(BDT)_(2)(HCOO)(H_(2)O)5]·0.5H_(2)O·3DMF}n (1)、{[Ce3(BDT)2(HCOO)(H_(2)O)_(5)]·3DMF}n (2)、{[Pr3(BDT)_(2)(HCOO)(H_(2)O)5]·3DMF}n (3)和{[Nd_(3)(BDT)_(2)(HCOO)(H_(2)O)_(5)]·3DMF}n (4),并采用单晶X射线衍射、粉末X射线衍射、元素分析、热重、傅里叶换红外光谱、N2吸附实验和荧光光谱对其进行表征。结果表明,这些Ln-MOFs均为单斜C2/m空间群晶体,是双核为无机建筑单元的三维介孔结构。其中2可选择性荧光检测Fe^(3+)离子和盐酸环丙沙星药物分子,检测限分别为4.59和0.77μmol·L^(-1)。

镧系金属有机框架化合物在发光传感检测领域的研究进展

镧系金属有机框架化合物(Ln-MOFs)材料是由镧系金属离子和有机配体通过配位键桥联形成的多孔晶态材料,是近年快速发展的一种新型功能性检测材料。Ln-MOFs具有比表面积大、孔道尺寸可调和结构可控等优势,在构建高选择性和高灵敏度的发光传感器领域有着广阔的应用前景,成为当前大量研究人员关心和研究的热点。镧系金属离子具有高配位数和高电荷,易与氧供给配体或氮供给配体相结合,除了La^(3+)和Lu^(3+)外,其他Ln^(3+)未完全充满的4f电子层结构可产生f-f或f-d跃迁发射,利用离子与配体的协同效应可以合成结构多样、发光性能良好的Ln-MOFs材料。Ln-MOFs的永久孔穴可以容纳各种客体物质与框架产生相互作用,外界环境和客体物质的微扰会改变Ln-MOFs的发光波长或强度,产生肉眼可见的颜色变化,并且可以将有机配体设计为发光位点,从而达到更好的传感效果,Ln-MOFs优异的结构和光致发光性质为制作传感材料提供了非常重要的基础。Ln-MOFs中最常见的检测形式是由外界环境因素和检测物引起的光诱导发射强度猝灭(Turn off)和增强(Turn on)。当检测物与Ln-MOFs发生能量竞争,通过配体与检测物之间的相互作用改变能量传递过程,部分能量从配体转移到分析物,能量传递效率降低导致发射猝灭,而检测物增强Ln-MOFs的框架结构强度可有效提高能量传递效率和发光强度。本文聚焦了Ln-MOFs在发光传感领域检测离子、pH、有机小分子、硝基芳香族化合物、气体和温度的研究工作,着重介绍了该领域近期的研究进展,并对Ln-MOFs配体的选择与设计、灵敏性、重复利用性能和复杂环境的适用性进行了展望。

Highly sensitive luminescent lanthanide metal-organic framework sensor for L-kynurenine

L-kynurenine(L-kyn)is a marker of prostate cancer.At present,the expensive instruments are usually applied to detect L-kyn clinically,which limits its wide application for cancer diagnosis.Herein,three lanthanide metal-organic frameworks([Ln(CHO_(2))_(3)]_(n),Ln=Eu,Gd,and Tb)were designed and obtained,and detailly characterized by single crystal X-ray diffraction(SCXRD),powder X-ray diffraction(PXRD),Fourier transform infrared spectroscopy(FT-IR),thermogravimetric analysis(TGA),and luminescence spectroscopy.Further study reveals that[Tb(CHO_(2))_(3)]_(n)is a highly selective,ultra-sensitive,of strong anti-interference,highly stable,and non-expensive sensor for prostate cancer marker L-kyn.The limit of detection(LOD)for L-kyn sensing is a highly sensitive value of 1.0×10^(−9)mol/L.Furthermore,the sensing mechanism is discussed in detail.