Ultra-sensitive non-aggregation colorimetric sensor for detection of iron based on the signal amplification effect of Fe3+ catalyzing H2O2 oxidize gold nanorods.

Fe(3+) can catalyze H2O2 to oxidize along on the longitudinal axis of gold nanorods (AuNRs), which caused the aspect ratio of AuNRs to decrease, longitudinal plasmon absorption band (LPAB) of AuNRs to blueshift (Δλ) and the color of the solution to change obviously. Thus, a rapid response and highly sensitive non-aggregation colorimetric sensor for the determination of Fe(3+) has been developed based on the signal amplification effect of catalyzing H2O2 to oxidize AuNRs. This simple and selective sensor with a wide linear range of 0.

A cytotoxicity study of fluorescent carbon nanodots using human bronchial epithelial cells.

The labeling of living cells with carbon nanoparticles has been increasingly studied both in vivo and in vitro, but concerns about the potential cytotoxicity of these nanoprobes are also increasing. In this study, the fluorescent carbon dots (CDs) without surface modification was synthesized and evaluated for its cytotoxicity. Indicators including cell viability, total reactive oxygen species (ROS), glutathione, malondialdehyde and lactate dehydrogenase were assessed using human bronchial epithelial (16HBE) cell line.

Fullerol-fluorescein isothiocyanate-concanavalin agglutinin phosphorescent sensor for the detection of alpha-fetoprotein and forecast of human diseases.

Based on the reaction of the active -OH group in fullerol (F) with the dissociated -COOH group in fluorescein isothiocyanate (FITC) to form an F-FITC and the enhanced effect of N, N-dimethylaniline (DMA) on phosphorescence signal of F-FITC, a new phosphorescent labeling reagent (DMA-F-FITC) was developed. What's more, a phosphorescent sensor for the determination of alpha-fetoprotein variant (AFP-V) has been designed via the coupling technique of the high sensitivity for affinity adsorption-solid substrate-room temperature phosphorimetry (AA-SS-RTP) with the strong specificity reaction between DMA-F-FITC-Con A and AFP-V. The DMA-F-FITC increased the number of luminescent molecules in the biological target which improved the sensitivity of phosphorescent sensor.

Ultra-sensitive complex as phosphorescence probe for the determination of trace protein.

β-CD-HMTA-L-Tyr complex, formed in the host guest inclusion reaction carried out between host molecule β-cyclodextrin (β-CD) in β-CD-HMTA (HMTA is methenamine) and guest molecule L-tryptophan (L-Tyr), possessing the characteristic of room temperature phosphorescence (RTP). Bovine serum albumin (BSA) reacted with L-Tyr to form a complex of cage structure bringing in the sharply RTP signal quenching of L-Tyr. Based on the above facts, a new ultra-sensitive solid substrate room temperature phosphorimetry (SSRTP) for the determination of trace protein has been established using β-CD-HMTA-L-Tyr complex as a phosphorescence probe.

Zr(H2O)2EDTA modulated luminescent carbon dots as fluorescent probes for fluoride detection.

A novel fluorescent probe (Zr(CDs-COO)(2)EDTA) has been designed for fluoride ion (F(-)) content detection based on the competitive ligand reactions carried out between the carboxylate groups (-COOH) on the surface of the luminescent carbon dots (CDs) and F(-) coordinated to Zr(H(2)O)(2)EDTA. The strong and stable fluorescence signal of this probe was quenched upon the addition of F(-) as a result of the formation of the non-fluorescent complex Zr(F)(2)EDTA, due to the stronger affinity of F(-) than the -COOH in the CDs to Zr(IV). The fluorescence change (ΔF) in this process was linear with respect to the content of F(-), ranging from 0.

Selective determination of cysteine using BSA-stabilized gold nanoclusters with red emission.

Gold nanoclusters (AuNCs) were synthesized by a macromolecules template using bovine serum albumin (BSA) as stabilizer which can emit red photoluminescence under illumination of ultraviolet light. The fluorescence intensity of AuNCs enhanced through decreasing the surface defects of AuNCs modified with cysteine, herein we present a novel fluorometry for determination of trace cysteine. This method with a wider linear range from 2.

Catalytic solid substrate-room temperature phosphorimetry for the determination of residual perphenazine based on the electronic effect of rhodamine 6G.

The rhodamine 6G(+) -perphenazine (Rhod 6G(+) -PPH) compound is formed in the ester-exchange reaction between -OH of PPH and -COOC2 H5 of Rhod 6G(+) . PPH was oxidized to a red compound (PPH') in the presence of K2 S2 O8 . Interestingly, the room temperature phosphorescence (RTP) of Rhod 6G(+) was quenched because the -OH of PPH' reacted with -COOC2 H5 of Rhod 6G(+) -PPH to form Rhod 6G(+) -PPH' and PPH, which decreased the π-electron density (δ) of the carbon atom in the Rhod 6G(+) -PPH' conjugated system and enhanced the nonradiation energy loss of the excited Rhod 6G(+) of the triplet state.

CdS/TiO2-fluorescein isothiocyanate nanoparticles as fluorescence resonance energy transfer probe for the determination of trace alkaline phosphatase based on affinity adsorption assay.

The CdS/TiO(2)-fluorescein isothiocyanate (FITC) luminescent nanoparticles (CdS/TiO(2)-FITC) with the particle size of 20 nm have been synthesized by sol-gel method. CdS/TiO(2)-FITC could emit the fluorescence of both FITC and CdS/TiO(2). The fluorescence resonance energy transfer (FRET) occurred between the donor CdS/TiO(2) and the acceptor FITC in the CdS/TiO(2)-FITC.

A specific Tween-80-Rhodamine S-MWNTs phosphorescent reagent for the detection of trace calcitonin.

The present study proposed a simple sensitive and specific immunoassay for the quantification of calcitonin (CT) in human serum with water-soluble multi-walled carbon nanotubes (MWNTs). The COOH group of MWNTs could react with the NH group of rhodamine S (Rhod.S) molecules to form Rhod.

Determination of trace human chorionic gonadotropin by using multiwall carbon nanotubes as phosphorescence labeling reagent.

Taking advantage of the cutting effect of the strong oxidation of benzoyl peroxide [(C(6)H(5)CO)(2)O(2)] on the end of multiwall carbon nanotubes (MWNTs) to obtain water-soluble multiwall nanotubes (MWNTs') and the spiking effect of polyacrylamide (PA) on the room temperature phosphorescence (RTP) of MWNTs', a new phosphorescent labeling reagent, MWNTs'-PA, has been developed in this study. The product β-Ab(HCG)-MWNTs'-PA obtained by MWNTs'-PA labeling human chorionic gonadotropin-β-subunit three-dimensional core monoclonal antibody (β-Ab(HCG)) not only could maintain good RTP characteristics of MWNTs' but also could take specific immunoreaction with β-HCG to form β-HCG- β-Ab(HCG)-MWNTs'-PA, resulting in the increase of MWNTs' RTP signal. Thus, a new solid substrate room temperature phosphorescence immunoassay (SSRTPIA) for the determination of β-HCG has been established.

Coupling technique of self-ordered ring and phosphorimetry for the determination of alkaline phosphatase and diseases prediction.

Rhodamine S could emit strong and stable room temperature phosphorescence (RTP) on polyamide membrane (PAM) in the presence of heavy atom perturber Pb(2+). When Rhodamine S-piperidine solution was dropped on PAM, the red (Rhod.S)(n)-P-SOR (Rhod.

Research on the spectral properties of luminescent carbon dots.

This paper is trying to research the developing status of carbon dots (CDs), and the results show that the simple, rapid and high yield synthetic methods for CDs and the application of CDs in biological science and analysis field will certainly become an inevitable development trend in the future. The CDs obtained by microwave possess excellent optical properties including UV-Vis absorption, fluorescence and room temperature phosphorescence. Under the conditions of 30 °C and 10 min, the fluorescence signal (F) of CDs not only could be enhanced by hexadecyltrimethylammonium bromide (CTAB), Triton X-100, Na(2)S, Na(2)C(2)O(4) and NH(3).

Highly selective and sensitive detection of Cu2+ with lysine enhancing bovine serum albumin modified-carbon dots fluorescent probe.

Based on the ability of lysine (Lys) to enhance the fluorescence intensity of bovine serum albumin modified-carbon dots (CDs-BSA) to decrease surface defects and quench fluorescence of the CDs-BSA-Lys system in the presence of Cu(2+) under conditions of phosphate buffer (PBS, pH = 5.0) at 45 °C for 10 min, a sensitive Lys enhancing CDs-BSA fluorescent probe was designed. The environment-friendly, simple, rapid, selective and sensitive fluorescent probe has been utilized to detect Cu(2+) in hair and tap water samples and it achieved consistent results with those obtained by inductively coupled plasma mass spectroscopy (ICP-MS).

Highly sensitive detection of residual chlorpromazine hydrochloride with solid substrate room temperature phosphorimetry.

Under the condition of 60 °C and 20 min at pH 6.12, chlorpromazine hydrochloride (CPZ) could react with fluorescein isothiocyanate (FITC) to produce FITC-CPZ, which increased the π-electron density (δ) of carbon atom in FITC conjugated system and the room temperature phosphorescence (RTP) intensity of FITC. Thus, a new solid substrate room temperature phosphorimetry (SSRTP) for the determination of residual CPZ was established.

A highly sensitive coupling technique for the determination of trace quercetin based on solid substrate room temperature phosphorimetry and poly (vinyl alcohol) complex imprinting.

Al(3+) could react with quercetin (Q) to form [AlQ](3+) complex which could be used as a template for the preparation of poly (vinyl alcohol)-[AlQ](3+) complex imprinting (PVA-C-I). The [AlQ](3+) not only had good matching ability and selectivity with the cavity of PVA-C-I, but also could react with the fluorescein isothiocyanate anion (FITC(-)) on the outside of cavity by electrostatic interaction to form ion-association complex [AlQ](3+)·[(FITC)(-)](3). The ion-association complex could emit strong and stable room temperature phosphorescence (RTP) on polyamide membrane (PAM) and the ΔI(p) of the system had linear relationship with the content of Q, showing the highly selective identification of PVA-C-I to Q.

A colorimetric probe for online analysis of sulfide based on the red shifts of longitudinal surface plasmon resonance absorption resulting from the stripping of gold nanorods.

A gold nanorods (GNRs) nonaggregation-based colorimetric probe has been developed for the detection of S(2-) based on that the longitudinal surface plasmon resonance absorption wavelength (LPAW) of GNRs red shifts (Δλ) and the color of the solution distinctly changes on account of the faster stripping of GNRs along longitudinal axis than transverse axis in the process of GNRs reacting with S(2-) ions to form Au(2)S complexes on the GNRs surfaces. The GNRs probe exhibits highly sensitive and selective response toward S(2-) with a wide linear range from 10.0 to 10000.

Catalytic solid substrate-room-temperature phosphorimetry detection for trace cadmium with Cd2+ -3.5-generation polyamidoamine dendrimer-Tween-80 complex.

3.5-Generation polyamidoamine dendrimers (3.5-G-D) emitted strong and stable room-temperature phosphorescence (RTP) on filter paper when Pb2+ was used as a heavy atom perturber.

Catalytic solid substrate room temperature phosphorimetry for the determination of trace rhamnose based on its condensation reaction with calcein.

Calcein (R) could not only emit strong and stable room temperature phosphorescence (RTP) on filter paper using I(-) as perturber, but also could be oxidized by H(2)O(2) to form a non-phosphorescence compound (R'), resulting in the quenching of RTP signal of R. Moreover, the ortho-hydrogen of phenolic hydroxyl in R took condensation reaction with rhamnose (Rha) to produce non-phosphorescence compound (R-Rha) causing the RTP signal of R to further quench, and R-Rha was oxidized by H(2)O(2) to form R' and Rha, bringing about the sharp RTP signal quenching of R. Thus, a new solid substrate room temperature phosphorimetry (SSRTP) for the determination of trace Rha based on its strong catalytic effect on H(2)O(2) oxidizing R has been established, with the detection limit (LD) of 7.

A promising CdSe@CdS-quantum dots-cysteine for the determination of trace IgE by solid substrate room temperature phosphorescence immunoassay.

The labelling reagent CdSe@CdS-QDs-Cys (QDs-Cys) with the grain diameter of 4.5 nm was synthesized by modifying CdSe@CdS quantum dots (QDs) with cysteine (Cys). At the same time, QDs-Cys-Ab(IgE), a phosphorescent quantum dot probe, was developed based on the labelling reaction between -COOH of QDs-Cys and -NH(2) of goat anti human IgE antibody (Ab(IgE)).

Determination of trace gastrin and diagnosis of human diseases using CdTe quantum dots labelled gastrin antibodies as phosphorescence sensors.

CdTe quantum dots (CdTe-QDs) can emit strong and stable room temperature phosphorescence (RTP) via the perturbation effect of a Pb(2+) ion on the surface of a nitrocellulose membrane (NCM). CdTe-QDs-Ab(GAS), the product of CdTe-QDs labelled gastrin antibodies (Ab(GAS)), can not only maintain good RTP characteristics, but can also be used as a RTP sensor and carry out highly specific immunoreactions with gastrin (GAS) to form GAS-Ab(GAS)-CdTe-QDs causing the ΔI(p) of the system to sharply enhance. Thus, a new solid substrate room temperature phosphorescence immunoassay (SSRTPIA) for the determination of GAS was established based on the linear relativity between the ΔI(p) of the system and the content of GAS.

Determination of trace carvedilol by solid substrate-room temperature phosphorimetry, based on its activating effect on hypochlorite-oxidizing amaranth using sodium dodecyl benzene sulphonate as sensitizer.

This work proposes a simple and sensitive solid substrate-room temperature phosphorimetry (SS-RTP) for the selective determination of carvedilol (CV). The method is based on the sensitizing effect of sodium dodecyl benzene sulphonate (SDBS) on CV to activate the oxidation between NaClO and amaranth, resulting in the intense quenching of room temperature phosphorescence (RTP) of the system. Compared with non-SDBS system, the reduction of phosphorescence intensity (ΔI(p)) with SDBS is 16.

Determination of trace deoxyribonucleic acid by using fluorescein isothiocyanate-phenosafranine as a double-luminescent phosphorescence probe.

Using Pb(2+) as ion perturber, phenosafranine (PF) and fluorescein isothiocyanate (FITC) could emit strong and stable room temperature phosphorescence (RTP) signal on the filter paper, respectively. When they were mixed, the phenomenon that the RTP signal of PF and FITC enhanced significantly was found. And 1.

Fullerol-fluorescein isothiocyanate phosphorescent labeling reagent for the determination of glucose and alkaline phosphatase.

The active -OH group in fullerol (F-ol) could react with the dissociated -COOH group in fluorescein isothiocyanate (FITC) to form F-ol-(FITC)(n), which could emit room temperature phosphorescence (RTP) signal of F-ol and FITC on acetate cellulose membrane (ACM), respectively. Their RTP signals were enhanced by N,N-dimethylaniline (DMA). The labeling reaction between the -NCS group of FITC in DMA-F-ol-(FITC)(n) and the -NH2 group in wheat germ agglutinin (WGA) produced DMA-F-ol-(FITC)(n)-WGA, which could further take affinity adsorption (AA) reaction with bioactive substances (BS), such as glucose and alkaline phosphatase (AP), to produce DMA-F-ol-(FITC)(n)-WGA-BS.

Analysis application in biological field and prediction of human diseases with dual luminescence molecular of 3.5-generations polyamidoamine dendrimers-porphyrin.

A new phosphorescence-labelling reagent (3.5-G-D-P labelling reagent) was developed, based on 3.5-generation polyamidoamine dendrimers (3.