Preparation of Micron-size Functional Fluorescent Microspheres

As a kind of special functional microspheres, fluorescent polymer microspheres could be used in cell label and separation, blood flow assay, flow cytometer marking, chemical reaction assay, and in analyst of the transform and diffusion of particles in soil . However, one of the most 1 important applications of fluorescent microspheres is in the high-throughput screening of drugs (HTS) . Through affinity interaction, radioactive ligands (latent drugs) are bound to fluorescent 2 microsphere…     

Recent development in fluorescent probes based on attacking of double bond and masking of functional group

The works on the procedure of fluorescent sensors for the detection of biological analytes are extremely momentous.Among diverse analytical approaches,fluorescence is the most eye-catching due to its high sensitivity,selectivity,rapidity,robustness,ease of measurement and non-destructive approaches.Herein,we show different fluorescent probes synthesized for estimation and detection of biological analytes(H₂S,SO₃^2-/HSO₃^-,H₂O_2<...     

Signal-on bimodal sensing glucose based on enzyme product-etching MnO_2 nanosheets for detachment of MoS_2 quantum dots

The sensitive and rapid detection of blood glucose is very important for monitoring and managing diabetes.Herein,a fluorescent/magnetic bimodal sensing strategy is proposed for glucose detection using a multifunction-responsive nanocomposite(MoS_2 QDs-MnO_2 NS).MoS_2 QDs act as fluorescent probes,and MnO_2 nanosheets are used as both quenchers and recognizers in this sensing platform.In the presence of glucose-mediated enzyme product(H_2 O_2),MnO_2 nanosheet is etched,thus releasing MoS_2 QDs and Mn~(2+)ions,which causes the significantly enhancement of fluorescent and magnetic signals.Furthermore,MoS_2 QDs-MnO_2 NS-based fluorescent test paper is constructed for H_2 O_2 sensing with the naked eyes.Under optimal conditions,the dual linear ranges of 20-300 μmol/L and 40-250 μmol/L toward glucose detection are obtained for the fluorescent and magnetic mode,respectively.Furthermore,this bimodal assay exhibits good reproducibility and acceptable accuracy in glucose detection of clinical samples,demonstrating great versatility and flexibility of multifunctional probes in glucose detection.     

基于(R)-1,1’-联萘硫脲的手性荧光受体: 合成与手性识别

Two chiral fluorescent receptors 1 and 2 based on (R)-1,1‘-binaphthylene-2,2‘-bisthiourea were synthesized, and their chiral recognition properties for enantiomeric mandelate anions were studied by fluorescence spectra and molecular modeling. Addition of the L- and D-mandelate anions caused considerable fluorescent increases in the fluorescent intensity of the host solution. The L-enantiomer can enhance the fluorescence intensity of 1 much more than the D-enantiomer can do, and 1 shows a better enantioselective recognition ability than 2.     

High-throughput Screening: Synthesis of a Novel Fluorescent Microspheres

As one of efficient analytes, fluorescent microspheres have shown much usability on many biochemical and biomedical processes. Recent applications with fluorescent microspheres have included cytokine quantitation, single nucleotide polymorphism genotyping, phosphorylated protein detection, and characterization of the molecular interaction of nuclear receptors. These, coupled with the rapid advances in molecular biology and synthesis techniques of drugs, have presented a basis for drug screenin…     

Development of Enantioselective Fluorescent Sensors for Chiral Recognition

Novel chiral compounds have been synthesized for the enantioselective fluorescent recognition of alpha-hydroxycarboxylic acids and amino acids. By introducing dendritic branches to the chiral receptor units, the fluorescence signals of the receptors are significantly amplified because of the light-harvesting effect of the dendritic structure. This has greatly increased the sensitivity of the sensors in the fluorescent recognition. Highly enantioselective fluorescent responses have also been ac…     

Synthesis and application of rhodamine-based fluorescent probe dyes with spacer linker arm

When rhodamine-based fluorescent probe dyes are used to track target molecules they always perturb the behavior of target molecules because of steric hindrance effect. In order to minimize potential steric problems, a kind of rhodamine-based fluorescent probe dye with spacer linker arm was designed and synthesized and its application in immunofluorescence histochemistry was investigated.     

The Different Fluorescent Response of Quin 2 to the Binding of Ca^2＋ and La^3＋ and its Application

The fluorescence spectra of Quin 2, (2-[(2-bis-[carboxymethyl] amino-5-methylphenoxy)methyl]-6-methoxy-8-bis [carboxymethyl] aminoquiniline), a Ca^2 probe, were investigated upon incubation with Ca^2 or La^3 . The results showed that binding of La^3 to Quin 2 resulted in different fluorescent spectrum from that of Ca^2 . Based on this observation, a fluorescent method was developed for simultaneously determination of the dissociation rates of Ca^2 and La^3 from a Ca-La- calmodulin complex (Ca2La2CaM).     

Synthesis, structure and photoluminescent property of a novel potassic compound

A novel 3D coordination compound of K(H2TDA)(H20)(1)(H_3TDA=1H-1,2,3-triazole-4,5-dicarboxylic acid) has been prepared and characterized by IR spectroscopy,elemental analysis,ICP and single-crystal X-ray diffraction.Compound 1 displays strong fluorescent emission at room temperature.     

Synthesis and Analytical Application of Bis（2-diazoaminobenzothiazoyl）-benzidine to Determination of Mercury Ion by Fluorimetry

A new fluorescent reagent bis(2-diazoaminobenzothiazoyl)-benzidine(BDABTB) was synthesized by combining benzothiazole with benzidine and triazene reagent. The product was confirmed by elemental analysis, 1H NMR and FTIR. The excitation and emission wavelengths of BDABTB were 214 and 338 nm in a basic medium, respectively. The fluorescence was quenched by Hg2+ selectively and sensitively. The linear range of Hg2+ was 1.0×10-8―1.0×10-5 mol/L with a detection limit of 5.0×10-10 mol/L. It has been used to deter...     

N-(8-对氨基苯磺酰)胺基喹啉的合成及其荧光性质的研究

合成了一种Zn2+荧光探针N-(8-对氨基苯磺酰)胺基喹啉(HQAS),探讨了HQAS与Zn2+的键合比和配位模式,以及不同pH,其它金属离子对Zn2+检测的影响.研究结果显示:该探针与Zn2+形成配合物,使其荧光增强,键合比为2:1,pH 7.2时荧光强度增大9.4倍.大多数金属离子几乎不干扰Zn2+的检测,Cu2+...     

8-Hydroxyquinoline derivative as a fluorescent chemosensor for zinc ion.

8-Hydroxyquinoline derivative 1 as a fluorescent chemosensor for Zn2+ was synthesized. Because Cd2+ is often found with Zn2+ in the environment and can form fluorescent complexes with chelating fluorophores, a potentially important property of chemosensors for Zn2+ is their selectivity for Zn2+ over Cd2+. The Zn2+ or Cd2+ complexes of 1 gave an emission band from the 1:1 complex, but the fluorescence intensity for Cd2+ was a half of that for Zn2+. Ligand 1 is suited for use as a fluorescent chemosensor for Zn2+.     

开链冠醚Schiff碱配体与过渡金属离子相互作用研究

合成了开链冠醚Schiff碱配体H₂L(H₂L=N,N′-双(邻羟苯亚甲基)-3,6-二氧杂-1,8-二氨基辛烷).详细研究了该配体在不同溶剂中和过渡金属离子存在下的荧光光谱,探讨了溶剂极性和不同金属离子对其荧光光谱的影响.结果表明:溶剂的极性和金属离子对其荧光性质有较大影响,随着溶剂极性的减小,配体的荧光增强,且谱峰发生蓝移.金属离子Zn²⁺、Cd²⁺对配体具有荧光增敏作用,Ni²⁺、Cu²⁺具有荧光猝灭作用.探讨了配体与金属离子结合的pH范围,结果显示最佳pH值为7—8.     

Synthesis of a novel calix[4]arene-based fluorescent ionophore and its metal ions recognition properties

A novel fluorescent ionophore derived from calix[4]arene and pyrazoline was designed and synthesized. Its molecular structure was confirmed by 1H NMR and element analysis. The resulting material shows specific fluorescent behavior toward the Zn2+ ion among the other divalent metal ions, such as Co2+, Ni2+, Cu2+. The primary results indicate this ionophore material is a potential material for developing efficient fluorescent Zn2+ chemosensors.     

Development of selective,visible light-excitable,fluorescent magnesium ion probes with a novel fluorescence switching mechanism

Novel fluorescent Mg2+ probes, 2'-carboxyfluorescein (2'-CF) and its derivatives, that are excitable by visible light, were designed, synthesized and characterized. After complexation with Mg2+, the absorption and emission maxima of these fluorescent probes were red-shifted and the fluorescence intensity was increased 11-fold at neutral pH. The apparent dissociation constant (Kd) of the Mg2+-2'-CF complex was 15.8 mM at neutral pH. The Kd of the Ca2+-2'-CF complex was about 10 times larger than that of the Mg2+ complex and the other derivatives showed similar characteristics. In contrast, all the commercially available fluorescent Mg2+ probes have a higher affinity for Ca2+ than Mg2+. 2'-CF fluoresced in alkaline solution (pH > 8) and the pK, value was 8.8. The pKa value of the Mg2+-2'-CF complex was 6.8, and the fluorescence intensity was increased in the neutral conditions. Thus, the addition of Mg2+ resulted in a lowering of the pKa, and also an increase of the fluorescence intensity.     

New fluorescent and colorimetric chemosensors based on the rhodamine and boronic acid groups for the detection of Hg

Novel rhodamine B (RB) derivatives bearing mono and bis-boronic acid groups were investigated as Hg²⁺ selective fluorescent and colorimetric sensors. These derivatives are first examples of reversible fluorescent chemosensors for Hg²⁺ which utilized boronic acid groups as binding sites. Two new RB-boronic acid derivatives displayed selective ‘Off-On’-type fluorescent enhancements and distinct color changes with Hg²⁺. Selective fluorescent enhancement of two rhodamine derivatives was attributed to ring opening from the spirolactam (nonfluorescent) to ring-opened amide (fluorescent).     

A water-soluble "switching on" fluorescent chemosensor of selectivity to Cd2+

Compound 1, a new fluorescent chemosensor signaling via significantly enhanced fluorescence when bound with cation analytes, was synthesized and characterized. This fluorescent chemosensor exhibits its selectivity to Cd2+ among a series of cations in HEPES buffer solution. Its in vitro sensitivity to Cd2+ was demonstrated in the HK-2 cell line with use of confocal microscopy. The mechanistic selectivity and sensitivity of compound 1 to Cd2+ was discussed on the basis of fluorescence, 1H NMR, and mass spectroscopic results.     

Rhodamine-based chemosensing monolayers on glass as a facile fluorescent “turn-on” sensing film for selective detection of Pb

Rhodamine-based chemosensors 1 and 2 were synthesized and self-assembled onto glass surfaces for the selective fluorescent sensing of Pb²⁺. The immobilized chemosensors showed fluorescent responses that were turned-on with Pb²⁺ in CH₃CN, selectively over various metal ions. The Pb²⁺-selective fluorescent switch of the immobilized chemosensors was also reversible, allowing for repeated use for Pb²⁺ detection.     

Construction of Fluorescent Probes Via Protection/Deprotection of Functional Groups: A Ratiometric Fluorescent Probe for Cu2+

Herein a ratiometric fluorescent Cu²⁺ probe was rationally constructed in a straightforward manner with the concept of aldehyde group protection/deprotection. The probe showed a ratiometric fluorescent response to Cu²⁺ with a large emission wavelength shift (>100 nm) and displayed high selectivity for Cu²⁺ over other metal ions due to distinct deprotection conditions. In addition, a Cu²⁺‐promoted dethioacetalization mechanism was proposed.