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Fluorescein (HFin) could emit strong and stable room temperature phosphorescence (RTP) signal on polyamide membrane (PAM) using Pb as the ion perturber. Carbaryl could activate effect on NaIO oxidating HFin, which caused the RTP signal of the system to quench sharply. The phosphorescence intensity (Δ I) of activating system higher 3.3 times (119.4/36.0) than that of non-activating system, and is directly proportional to the content of carbaryl. Thus, an activating solid substrate room temperature phosphorimetry (SSRTP) for carbaryl detection has been established. This sensitive (the limit of quantification (LOQ) was 2.0 × 10 g mL), selective, simple and rapid method has been applied to determine trace carbaryl in water samples with the results consisting with those obtained by fluorimetry, showing its high accuracy. The apparent activation energy ( E) and rate constant ( k) of this activating reaction were 20.77 kJ mol and 1.85 × 10 s, respectively. Meanwhile, the mechanism of activating SSRTP for carbaryl detection was also discussed using infrared spectra (IR). [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]

A novel solid substrate-room temperature phosphorimetry (SS-RTP) was developed for determination of bumetanide (BMTN). It was validated by determining selectivity, linearity, accuracy, precision, and signal to noise ratio (S/N) for analysis. And all the experiments presented in this work were based on that BMTN inhibited the formation of [Fe-morin]3+ ([FeR]3+) complex by the reaction between Fe3+ and R, which led to severe quenching of room temperature phosphorescence (RTP) signal. The rate constant of the reaction (k) was 2.44 × 10−4 s−1, the activation energy (E) was 21.39 kJ mol−1. Detection limit of this method (LD, 5.0 ag spot−1, corresponding concentration was 1.2 × 10−14 g mL−1) was evaluated and compared with other methods, indicating better sensitivity for BMTN determination using this technique. And due to the high sensitivity of the method, it has been successfully applied to determine BMTN in human urine samples. The linear range was from 0.040 pg mL−1 to 4.0 pg mL−1, allowing wide determined range of BMTN. Meanwhile, the mechanism of this method was also discussed. [ABSTRACT FROM AUTHOR]

Multi-wall carbon nanotubes (MWNTs) could be modified as water soluble MWNTs (it was called as MWNTs-A and MWNTs-B) by chemical methods. MWNTs-A and MWNTs-B could emit room temperature phosphorescence (RTP) signal on the surface of nitrocellulose membrane (NCM). A new solid substrate-room temperature phosphorimetry (SS-RTP) for the determination of trace alkaline phosphatase (ALP) was established based on the signal magnification effect of tween-80 and ALP on MWNTs-B’s RTP intensity and the linear relationship between the content of ALP and the Δ IP of the system. The linear range of this method was 0.0020–0.80 (fg spot−1, sample volume: 0.40 μl spot−1), the regression equation of working curve was $$ \Delta {I_P} = 0.8170 + 96.84{m_{ALP}}\left( {fg{ }spo{t^{ - 1}}} \right) $$, correlation coefficient ( r) was 0.9986. This method had high sensitivity (detection limit (LD): 1.4 ag spot−1), good selectivity (Er ≤ ± 5c/o, coexistence species were of no interference), high precision (RSDs were 4.4%-1.2%) and accuracy. It was applied to the determination of trace ALP in human serum and the diagnosis of human diseases. The results were tallied with those of enzyme-linked immunosorbent assay (ELISA). The mechanism of new SS-RTP for the determination of trace ALP was discussed, which laid the theory foundation for the analytical application of MWNTs in life science. [ABSTRACT FROM AUTHOR]

This research combined the self-ordered ring (SOR) technology with solid substrate-room temperature phosphorimetry (SS-RTP) and developed a new (ARS)n-P-SOR (ARS is alizarin red S, (ARS)n refers to multiple ARS molecules, P is piperidine). (ARS)n-P-SOR could increase the number of ARS molecules in the biological target, which could further improve the sensitivity of SS-RTP. Thus, a new SS-RTP for the determination of trace deoxyribonucleic acid (DNA) was established using (ARS)n-P-SOR as a phosphorescent probe. This method was successfully applied to the determination of DNA in nectar. Meanwhile, the mechanism of determining trace DNA by (ARS)n-P-SOR was discussed. [ABSTRACT FROM AUTHOR]

Abstract: Fluorescein (HFin) emitted strong and stable room temperature phosphorescence (RTP) on filter paper after set at 50°C for 10min using Li+ as the ion perturber. HFin existed as Fin− when the pH value was in the range of 5.45–7.36. Fin− could react with [Cu(BPY)2]2+ (BPY: α,α-bipyridyl) to produce ion association complex [Cu(BPY)2]2+·[(Fin)2]2−, which could enhance the RTP signal of Hfin. In the presence of bovine serum albumin (BSA), the –COOH group of Fin− in the [Cu(BPY)2]2+·[(Fin)2]2− could react with the –NH2 group of BSA to form the ion association complex [Cu(BPY)2]2+·[(Fin-BSA)2]2−, which contained –CO–NH– bond. This complex could sharply enhance the RTP signal of Hfin and the ΔI p was directly proportional to the content of BSA. According to the facts above, a new solid substrate-room temperature phosphorimetry (SS-RTP) for the determination of trace protein had been established using the ion association complex [Cu(BPY)2]2+·[(Fin)2]2−as a phosphorescent probe. This method had wide linear range (0.40×10−9–280×10−9 mgl−1), high sensitivity (the detection limit (LD) was 1.4×10−10 mgl−1), good precision (RSD: 3.4–4.9%) and high selectivity (the allowed concentration of coexistent ions or coexistent materials was high). It had been applied to the determination of the content of protein in 10 kinds of real samples, and the result agreed well with pyrocatechol violet-Mo (VI) method (P.V.M.M.), which indicated it had high accuracy. Meanwhile, reaction mechanism for the determination of trace protein with [Cu(BPY)2]2+·[(Fin)2]2− phosphorescent probe was also discussed. The academic thought of this research could not only be used to develop many kinds of ion association complex phosphorescent probes, but also provided a new way to promote the sensitivity of SS-RTP. [Copyright &y& Elsevier]

Abstract: 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. Both of these two products could maintain the good RTP characteristics of F-ol and FITC. Based on the facts above, a new phosphorescent labeling reagent, DMA–F-ol–FITC, was developed, and a new affinity adsorption solid substrate room temperature phosphorimetry (AASSRTP) for the determination of BS was established. This method was applied to the determination of BS in human serum and the diagnosis of diseases, with the results agreeing very well with those of enzyme-linked immunosorbent assay (ELISA). The mechanism of DMA–F-ol–(FITC) n labeling of WGA and AASSRTP for the determination of BS is discussed. [Copyright &y& Elsevier]

Abstract: The 8-quinolineboronic acid phosphorescent molecular switch (abbreviated as PMS-8-QBA. Thereinto, 8-QBA is 8-quinolineboronic acid, and PMS is phosphorescent molecular switch) was found for the first time. PMS-8-QBA, which was in the “off” state, could only emit weak room temperature phosphorescence (RTP) on the acetyl cellulose membrane (ACM). However, PMS-8-QBA turned “on” automatically for its changed structure, causing that the RTP of 8-QBA in the system increased, after PMS-8-QBA-WGA (WGA is wheat germ agglutinin) was formed by reaction between –OH of PMS-8-QBA and –COOH of WGA. More interesting is that the –NH2 of PMS-8-QBA-WGA could react with the –COOH of alkaline phosphatase (AP) to form the affinity adsorption (AA) product WGA-AP-WGA-8-QBA-PMS (containing –NH–CO– bond), which caused RTP of the system to greatly increase. Thus, affinity adsorption solid substrate room temperature phosphorimetry using PMS-8-QBA as labelling reagent (PMS-8-QBA-AA-SSRTP) for the determination of trace AP was established. The method had many advantages, such as high sensitivity (the detection limit (LD) was 2.5zgspot−1. For sample volume of 0.40μlspot−1, corresponding concentration was 6.2×10−18 gml−1), good selectivity (the allowed concentration of coexisting material was higher, when the relative error was ±5%), high accuracy (applied to detection of AP content in serum samples, the result was coincided with those obtained by enzyme-linked immunoassay), which was suitable for the detection of trace AP content in serum samples and the forecast of human diseases. Meanwhile, the mechanism of PMS-8-QBA-AASSRTP was discussed. The new field of analytical application and clinic diagnosis technique of molecule switch are exploited, based on the phosphorescence characteristic of PMS-8-QBA, the AA reaction between WGA and AP, as well as the relation between AP content and human diseases. The research results promote the development and interpenetrate among molecule switch technique, lectin science and SSRTP. [Copyright &y& Elsevier]

Abstract: 8-Quinolineboronic acid phosphorescent molecular switch (8-QBA-PMS) in the “off” state emitted weak room temperature phosphorescence (RTP) of 8-QBA on the acetylcellulose membrane (ACM) with the perturbation of Pb2+. When 8-QBA-PMS was used to label concanavalin agglutinin (Con A) to form 8-QBA-PMS-Con A based on the reaction between –OH of 8-QBA-PMS and –COOH of Con A, 8-QBA-PMS turned “on” automatically due to its structure change, and RTP of the system increased 2.7 times. Besides, –NH2 of 8-QBA-PMS-Con A could carry out affinity adsorption (AA) reaction with the –COOH of alpha-fetoprotein variant (AFP-V) to form the product Con A-AFP-V-Con A-8-QBA-PMS containing –NH–CO– bond, causing the RTP of the system to further increase. Moreover, the amount of AFP-V was linear to the ΔI p of the system in the range of 0.012–2.40 (fgspot−1). Thus, a new affinity sensitive adsorption solid substrate room temperature phosphorimetry using 8-QBA-PMS as labelling reagent (8-QBA-PMS-AASSRTP) for the determination of AFP-V was proposed with the detection limit (LD) of 9×10−15 gmL−1. It had been used to determine AFP-V in human serum with the results agreeing with enzyme-link immunoassay (ELISA), showing promise for the prediction of PHC due to the intimate association between AFP-V and primary hepatocellular carcinoma (PHC). The mechanism of the promethod was also discussed. [Copyright &y& Elsevier]