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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. The proposed sensor was responsive, simple, selective and sensitive, and it has been applied to the determination of trace AFP-V in human serum and the forecast of human diseases using phosphorescence emission wavelength of F or FITC, with the results agreed well with those obtained by enzyme-linked immunoassay (ELISA). Meanwhile, the mechanisms for the labeling reaction and the sensing detection of AFP-V were discussed., (Copyright © 2013 Elsevier B.V. All rights reserved.)

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).H(2)O, but also could be quenched by sodium dodecyl sulfate, KBrO(3), K(2)S(2)O(8), NaIO(4), ascorbic acid, NaBH(4), HNO(3), HCl, H(2)SO(4), CH(3)COOH and most metal ions, with the λ(em)(max) blue or red shifting in varying degrees, indicating the potential values of CDs in analytical application. Besides, the sensitive response of F to pH showed the promise of developing a new pH sensor with CDs., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Mechanoresponsive luminescent materials refer to materials exhibiting luminescence intensity and/or color change in the solid-state induced by external mechanical stimulation and are attracting considerable attention for their potential applications in many fields. For organic molecular materials, the mechanoresponsive luminescence phenomenon can significantly depend on the molecular packing modes and orientations of individual fluorophores, enabling the development of molecular materials with mechanoresponsive luminescence characteristics. Naphthalene diimides (NDIs) are well-known organic dyes with an electron-deficient plane, making them excellent candidates for exploring mechanoresponsive luminescence properties owing to their photophysical and photochemical properties that depend on the packing modes and are very sensitive to the micro-environment. In this work, a new binary charge transfer cocrystal complex with sensitive mechanoresponsive luminescence, IsoNDI·anisole (C1) (IsoNDI = N,N-di(4-pyridylacylamino)-1,4,5,8-naphthalene diimide), was designed and prepared. C1 shows interesting enhanced emission characteristics and reversible mechanochromic luminescence properties with a prominent color change from orange to bright green-yellow by mechanical grinding. This study demonstrates that the development of new mechanoresponsive luminescent materials through donor–acceptor interactions is an effective avenue. [ABSTRACT FROM AUTHOR]

Abstract: A new phosphorescence-labelling reagent (3.5-G-D–P labelling reagent) was developed, based on 3.5-generation polyamidoamine dendrimers (3.5-G-D) as internal acceptor to capture porphyrin (P) molecular. In the disturber of heavy atom, 3.5-G-D–P could emit room temperature phosphorescence (RTP) of 3.5-G-D and P on the surface of polyamide membrane (PAM), respectively. Products (3.5-G-D–P–WGA) of 3.5-G-D–P labelling triticum vulgaris lectin (WGA) could emit strong and stable RTP signal on the surface of PAM, and it also could take specific affinity adsorption reaction (AA) with alkaline phosphatase (ALP). The product of the AA reaction (3.5-G-D–P–WGA–ALP) could keep the RTP characteristics of 3.5-G-D–P very well, and the ΔI p of the system was linear correlation to the content of ALP. The ΔI p of the system with Tween-80 was once for P and twice for 3.5-G-D more than that without Tween-80. Thus, the affinity adsorption solid substrate-room temperature phosphorimetry (AA-SS-RTP) for the determination of trace ALP has been established using Tween-80–3.5-G-D–P to label WGA. The detection limit (LD) of this method was 0.12fgspot−1 for 3.5-G-D and 0.18fgspot−1 for P with direct method, 0.14fgspot−1 for 3.5-G-D and 0.17fgspot−1 for P with sandwich method, respectively, and the sensitivity was obviously high. This research showed that either using 3.5-G-D or P excitation/emission wavelength to determine the content of ALP in human serum, the results were coincided with ELISA, and the flexibility of AA-SS-RTP was obviously improved and the applicability was wider. Meanwhile, the reaction mechanism of determining ALP by direct method AA-SS-RTP was discussed. [Copyright &y& Elsevier]

Abstract: In this paper, 3.5-generation polyamidoamine dendrimers (3.5G-D)-porphyrin (P) dual luminescence molecule (3.5G-D-P) was developed as a new phosphorescence-labeling reagent. Meanwhile, the room temperature phosphorescence (RTP) characteristics of 3.5G-D-P and its product of labeling triticum vulgaris lectin (WGA) on the surface of polyamide membrane (PAM) were studied. Results showed that in the presence of heavy atom perturber LiAc, 3.5G-D and P of 3.5G-D-P molecule could emit strong and stable RTP on the PAM. And the Tween-80 would spike thoroughly the phosphorescence signal of 3.5G-D and P; moreover, specific affinity absorption (AA) reaction between the products (Tween-80-3.5G-D-P-WGA) of WGA labeled with Tween-80-3.5G-D-P and glucose (G) was carried out. The products of the AA reaction could keep good RTP characteristics of 3.5G-D and P dual luminescence molecule, and the ΔI p was linear correlation to the content of G. According to the facts above, a new method of affinity adsorption solid substrate-room temperature phosphorimetry (AA-SS-RTP) for the determination of trace G was established, basing on WGA labeled with Tween-80-3.5G-D-P dual luminescence molecule. The detection limit of this method was 0.13fgspot−1 (1.7×10−12 moll−1, 3.5G-D) and 0.14fgspot−1 (2.2×10−12 moll−1, P). Determination of G in human serum using excitation/emission wavelength of either 3.5G-D or P, the result was coincided with enzyme-linked immunosorbent assay (ELISA). Not only the sensitivity and accuracy of this method were higher, but also the flexibility of AA-SS-RTP was obviously improved and the applicability was wider. [Copyright &y& Elsevier]

A novel zinc-molybdenum(V) phosphate hybrid polymer, Zn[Mo6O12(OH)3(PO4)2(HPO4)2]2[Zn6(H2O)8(phen)4] ··· 6H2O (phen = 1,10-phenanthroline), was prepared under hydrothermal conditions and characterized by single-crystal X-ray diffraction, FT-IR, TGA and EPR spectra. The crystal structure analyses show that the compound is built from two anionic hexameric polyoxomolybdophosphate [Mo6O12(OH)3(PO4)2(HPO4)2]7- moieties, bridged by a central octahedral Zn2+ centre. The sandwich-type Zn[Mo6P4]2 dimers are connected via additional Zn2+ polyhedra, forming a two-dimensional network polymer. The luminescent properties of the title compound are also discussed. [ABSTRACT FROM AUTHOR]

Luminescent particles of lead carboxymethyl cellulose [Pb(CMC) 2 ] that contain luminescent salicyl fluorones (SAF) {[Pb(CMC) 2 ]‐SAF} were synthesized by sol‐gel method, using sodium carboxymethyl cellulose (NaCMC) as precursor and Pb 2+ as precipitator. [Pb(CMC) 2 ]‐SAF can emit intense and stable solid substrate–room temperature phosphorescence (SS‐RTP) on filter paper. EDTA (ethylenediaminetetraacetic acid) can chelate the Pb 2+ in [Pb(CMC) 2 ]‐SAF, causing it to decompose into aqueous soluble components PbY 2– , CMC – , and SAF, and these components can react with Cu 2+ to form [Cu(CMC) 2 ]‐SAF, causing decrease of phosphorescence intensity. Based on the facts above, a new method for the determination of trace mercury by SS‐RTP quenching method was established. This method has been applied to the determination of trace copper in human hair and tea samples with satisfactory results. [ABSTRACT FROM AUTHOR]

Abstract: Luminescent silicon dioxide nano-particles with size of 20nm, which containing dibromofluorescein (D) were synthesized by sol–gel method (symbolized by D–SiO2).The particles can emit intense and stable room temperature phosphorescence signal on polyamide membrane when Pb(Ac)2 was used as a heavy atom perturber. The λexmax/λemmax was 457/622nm. Our research indicated that the specific immune reaction between goat-anti-human IgG antibody labeled with D–SiO2 and human IgG could be carried out on polyamide membrane quantitatively, and the phosphorescence intensity of the particle was enhanced after the immunoreactions. Thus a new method of solid substrate room temperature phosphorescence immunoassay (SS-RTP-IA) for the determination of human IgG was established basing on antibody labeled with the D–SiO2 nanoparticles. The linear range of this method was 0.0624–20.0pg human IgG spot-1 (corresponding concentration: 0.156–50.0ngml-1, the sample volume: 0.40μlspot-1) with a limit of detection (LD) as 0.018pgspot-1, and the regression equation of working curve was ΔIp = 7.201mIgG (pgspot-1) + 82.57. Samples containing 0.156 and 50.0ngml-1 of IgG were measured repeatedly for 11 times and R.S.D.s were 4.1 and 3.4%, respectively. Results showed that this method had the merits as sensitive, accurate and precise. [Copyright &y& Elsevier]

Abstract: It was found that the solid substrate room temperature phosphorescence (SS-RTP) signal of some polyhalogenated derivatives of fluorescein (including eosin5-isothiocyanate) on a polyamide membrane can be enhanced obviously when an external inorganic salt was introduced into the system. The enhancement effect (RTP intensity and the ratio of signal to noise) of CaCl2 was much more notable than those of typical heavy atom perturbers in phosphorimetry, such as Pb(AC)2 and Hg(NO3)2, etc. According to that, a solid substrate room temperature phosphorescence immunoassay (SS-RTP-IA) with eosin5-isothiocyanate as a marker and CaCl2 as an enhancer for the determination of human complement 3 was developed. On a polyamide membrane, SS-RTP signals (λex/λem=532nm/685nm) of the immune complex are in linear correlation to the amount of human C3 in the range of 0.156–5.00pg/spot (the sample volume was 0.4μL/spot, corresponding concentration was 0.391–12.5ng/mL). The regression equation of working curve can be expressed as ΔIp (ΔIp=Isample-Iblank)=1.57+0.633mC3 (pg/spot), correlation coefficient r=0.998. The detection limit calculated as 3Sb/k is 0.12pg/spot. The method was directly applied to the determination of human complement 3 in human serums with satisfactory results. These results proved sufficiently that eosin-ITC is a good phosphorescent marker, while CaCl2 was used as the enhancer. Obviously, the results will expand the application area of these luminescent molecules, and using CaCl2 instead of Pb(AC)2 as a phosphorescence enhancer is more favorable for environment. [Copyright &y& Elsevier]

Abstract: Dissoluble manganese supramolecule containing rhodamine 6G luminescent particles (M2) are synthesized, based on dissoluble manganese supramolecule (M1) doping rhodamine 6G (R.6G), by crystalline method. The particle diameters of M1 and M2 determined by ETM are both of micron degree. M1 and M2 can emit solid substrate room temperature phosphorescence (SS-RTP) on filter paper. The transition probability from the singlet state (S1) to triplet state (T1) of the luminescent molecules was greatly enhanced, based on the increment of luminescent molecules for each spot and the heavy atom effect of certain amount of Pb2+. As a result, the phosphorescence intensity (I p) of M2 was increased sharply, and the enhancing value of phosphorescence intensity (ΔI p) is directly proportional to the concentration of Pb2+. Thus, a new method of SS-RTP enhancing for the determination of trace lead is established based on manganese supramolecule containing rhodamine 6G luminescent particles. The linear range of this method is 0.0040–0.400pgspot−1 of Pb2+ (corresponding concentration, 0.01–1.0ngmL−1; sample volume, 0.4μLspot−1), with a detection limit (LD) of 0.0011pgspot−1 (corresponding concentration, 2.8×10−12 gmL−1 of Pb2+, n =11). For the working solutions containing 0.0040 and 0.40ngmL−1 of Pb2+, they were determined repeatedly for seven times, respectively. The R.S.D.s were 3.2 and 3.8%, respectively. This method has good repeatability, sensitivity and high precision. It has been applied to the determination of trace lead in human hair and tea samples with satisfactory results. [Copyright &y& Elsevier]