3,6-Bis-β-Dicarbonylsubstituted Carbazoles Bearing N-Spacers and Their Eu(III) Complexes as Immunofluorescent Labelling Agents

New reagents for immunofluorescence analysis of carbazole series containing fluorinated β-dicarbonyl fragments and carboxylic substituent groups separated by spacers of different lengths from the light-gathering carbazole scaffold have been developed. The markers in complex with Eu3+ ions possess stability in the aqueous phase, intense and prolonged luminescence (τ 550 - 570 μs) with characteristic emission maxima in the region of 615 nm and excitation wavelengths in the region of 380 - 390 nm, which distinguishes them from most of the analogs used. In the study of marker conjugation with streptavidin, a reagent containing 4 - 5 europium labeling complexes based on spacer-containing carbazole tetraketone was obtained. The marker-doped silicate nanoparticles exhibit intense and long-lived luminescence in the characteristic region.

Assembling Tunable Time-Resolved Fluorescence Layer onto Nano-Gold

The assembling of a coating of time-resolved fluorescent chelator BSPDA （ abbreviated for 4, 7-bis （ sulfhydrylphenyl）-1, 10-phenanthroline-2, 9-dicarboxylic acid） onto a nano-gold layer was demonstrated. First, BSPDA was synthesized by simple procedures, and then an approach was developed to immobilize BSPDA onto the nano-gold layer deposited on a silane modified glass substrate, whereby europium ion （Ⅲ, Eu^3＋ ） was captured and released owing to the interactive process of complexation and dissociation between BSPDA functionalized coating and Eu^3＋ solution. The fluorescence spectra and related lifetimes were determined. Also, the BSPDA functionalized coating＇s specific complexation with Eu^3＋ on the BSPDA assembly layer and the nonspecific adsorption of Eu^3＋ on the nano-gold layer were compared. These results allowed a selective complexation of Eu^3＋ by assembling a BSPDA chelating layer on the nano-gold layer; thus, a tunable time-resolved fluorescent layer was covalently attached, The results of the nanoparticle assembling and probing （or labeling） processes to specific bio-systems were very interesting and had significant implications to time-resolved-fluorescence-based detection on biosensor surfaces such as DNA chip and to arrayed light display devices.

The Development of A Fluorescence Polarization Immunoassay for Aflatoxin Detection

A fluorescence polarization immunoassay （FPIA） was developed for the analysis ofaflatoxins （AFs） using an anti-aflatoxin B1 （AFB1） monoclonal antibody and a novel fluorescein-labeled AFB1 tracer. The FPIA showed an IC50 value of 23.33 ng/mL with a limit of detection of 13.12 ng/mL for AFB1. The cross-reactivities of AFB1, AFB2, AFG1, AFG2, AFM1, and AFM2 with the antibody were 100%, 65.7%, 143%, 23.5%, 111.4%, and 2%, respectively. The group-specificity of anti-AFB1mAb indicated that the FPIA could potentially be used in a screening method for the detection of total AFs, albeit not AFG2 and AFM2. The total time required for analyzing 96 samples in one microplate was less than 5 rain. This study demonstrates the potential usefulness of the FPIA as a rapid and simple technique for monitoring AFs.

Imaging Escherichia coli using streptavidin functionalized quantum dots as a Nano-fluorescent probe

It is extremely important for bacteria detection in many fields,such as medical diagnosis and food safety.In this paper,streptavidin functionalized quantum dots(SA-QDs),as a nano-fluorescent probe,were used to attach with Escherichia coli(E.coli) for the detection and identification of bacteria with immunoreactions and biotin-streptavidin affinity.Fluorescent images of the bacteria and the fluorescence intensity were used to evaluate the conjugation effect with different incubation time.Our results showed that 20 min is a reasonable incubation time for the SA-QDs coupling to E.coli cells.The fluorescent images,which produce a greatly amplified and enhanced signal of E.coli cells,were obtained through the immunological amplification and fluorescent probe enrichment steps.In addition,the bleaching process of SA-QDs without any encapsulation at room temperature was clearly observed during 10 min of being excited.Our work provided a modularized sample treatment method using SA-QDs as a nano-fluorescent probe in cellular imaging and bio-labeling.

Antibody Production for a Rapid Fluorescence Polarization Immunoassay of Estrone

Estrone has been identified as a potential endocrine-disrupting chemical （EDC）[1]. Estrone is usually quantified by gas chromatography-mass spectrometry （GC-MS）, GC-MS/MS, high performance liquid chromatography （HPLC）, HPLC- MS, and HPLC-MS/MS, etc.[2-3]. Meanwhile, several immunoassays based on radioimmunoassay, enzyme linked immunosorbent assay （ELISA） or chemiluminescence immunoassay （CLIA） for determination of estrone in real samples have been developed[2＇4]. Although these methods are sensitive, they need multistage separation and are thus time-consuming and laborious. A very promising way for the simplification of immunoassays for routine applications is a shift from heterogeneous methods （with separation） to homogeneous assays （without separation）[5]. Fluorescence polarization immunoassay （FPIA） is one of the homogeneous techniques that meets the requirements of a simple, reliable, fast, and cost-effective analysis[6]. Therefore, the present study is focused on the development of FPIA in order to analyze estrone based on antibody production.

A QUENCHING FLUORESCENCE IMMUNOASSAY METHOD FOR DETERMINATION OF TRACE ALBUMIN USING UNLABELED TERBIUM CHELATE

A fluoroimmunoassay method using unlabeled Terbium chelate is described.The principle is similar to that of fluoroimmunoassay method using lanthanide chelate as labels.The procedure is simpte because labeling process is unnecessary.The recovery of HSA and albumin in urine is 107% and 95% respectively.The standard deviation is tess than 10%.

动物源食品中孕酮激素残留的时间分辨荧光免疫分析法的建立

该研究以孕酮为研究对象,设计并制备了新抗原,通过动物免疫得到特异性兔抗体,基于所得抗原和抗体,进一步优化了抗原抗体浓度、反应缓冲液种类及其pH值等关键参数,最终在国内首次建立了用于动物性食品中性激素孕酮残留快速检测时间分辨荧光免疫分析法(TRFIA)。该研究确定最优实验条件为:抗原0.30μg/mL、铕标抗体0.40μg/mL、pH值7.2的TBST工作缓冲液,并建立标准曲线,方法的线性范围为0.46~6.94μg/L,IC_(50)达1.79μg/L,与睾酮交叉反应率为1.25%,与雌二醇、雌三醇等激素无交叉反应。实际样品的平均添加回收率为82.0%~113.0%,批内批间变异系数<5%,与高效液相色谱法(HPLC)检测结果的相关性良好(r2=0.988)。结果表明该研究所建立的TRFIA检测方法准确可靠、特异性好、灵敏度高,完全可用于动物源食品中孕酮残留的快速检测。

用于诺氟沙星现场灵敏检测的便携式智能手机赋能荧光传感技术

通过融合激光诱导荧光原理和光纤传感原理,集成全光纤光学系统、微型化流动进样系统、高灵敏微型光电探测系统和基于智能手机的APP软件,研制了用于水中抗生素现场快速灵敏检测的便携式智能手机赋能荧光生物传感器.以喹诺酮类抗生素诺氟沙星(NOR)为例,在优化条件下,该荧光生物传感器对NOR的检测限可达0.35μg/L,线性检测范围为1.6~20.6µg/L.所建立的NOR检测方法也被用于各种水样的NOR加标回收检测,其回收率为85%~120%,检测时间少于15min,表明其可以用于实际样品中NOR的现场灵敏快速检测.结合物联网等新兴技术,可根据设定的程序将检测结果直接上传环境监测监管中心,为实现水环境安全的监测预警和应急监测提供重要技术支持.

Effect of Deposition Temperature on Optical Properties of Porous Amorphous SiC Film

To study the effect of different deposition temperatures on the optical properties of porous SiC films,single crystal Si was used as the substrate,a layer of anodic aluminum oxide(AAO)film was transferred on the Si substrate by chemical method,and then a layer of SiC was deposited on anodic aluminum oxide(AAO)template to prepare porous fluorescent SiC film by magnetron sputtering.The deposition temperature was ranged from 373 to 873 K.The thickness of the porous SiC film coated on the AAO surface was around 283 nm.It is found that the porous SiC with the deposition temperature of 873 K has the strongest photoluminescence(PL)intensity excited by 375 nm laser.The time-resolved PL spectra prove that the PL is mainly from intrinsic light emitting of SiC.With the optimized process,porous amorphous SiC film may have potential applications in the field of warm white LEDs.

Time-Resolved Imaging in Short-Wave Infrared Region

Compared with the conventional first near-infrared(NIR-I,700900 nm)window,the short-wave infrared region(SWIR,900—1700nm)possesses the merits of the increasing tissue penetration depths and the suppression of scattering background,leading to great potential for in vivo imaging.Based on the limitations of the common spectral domain,and the superiority of the time-dimension,time-resolved imaging eliminates the auto-fuorescence in the biological tissue,thus supporting higher signal-to-noise ratio and sensitivities.The imaging technique is not affected by the difference in tissue composition or thickness and has the practical value of quan-titative in vivo detection.Almost all the relevant time-resolved imaging was carried out around lanthanide-doped upconversion nanomaterials,owing to the advantages of ultralong luminescence lifetime,excellent photostability,controllable morphology,easy surface modification and various strategies of regulating lifetime.Therefore,this review presents the research progress of SWIR time-resolved imaging technology based on nanomaterials doped with lanthanide ions as luminescence centers in recent years.

S100B时间分辨荧光免疫检测试剂盒的制备及性能评价

目的:制备一种快捷、准确、定量检测血清中S100B蛋白浓度的时间分辨荧光免疫检测试剂盒,并对其进行性能评价。方法:使用时间分辨荧光微球标记的抗S100B多克隆抗体及兔IgG抗体、标记垫、样品垫、S100B硝酸纤维素膜板、吸水纸制备试纸条,组装卡壳得到S100B时间分辨荧光免疫层析试剂盒。通过标准曲线、准确度、最低检测限、线性区间、特异度、重复性、稳定性等检测对该试剂盒进行性能评估。采用该试剂盒对某地区199例健康者血清及血浆样本的参考区间进行研究,并采用同步盲法测试该试剂盒与罗氏Elecsys S100检测试剂盒的临床应用性能,评估2种试剂盒对于142例样本检测结果的一致性。结果:该试剂盒所得标准曲线方程为y=(1.13302+1.75224)/[1+(x/1.08220)×(-0.60352)]-1.75224,R2=0.99908,线性范围为[0.05,30]ng/mL。该试剂盒可满足准确度相对偏差在±15%内、最低检测限≤0.05 ng/mL、特异度相对偏差在±15%内、批内差和批间差的变异系数均<15%的产品设计要求。稳定性检测结果标明该试剂盒可在2~30℃条件下有效保存12个月。同时,通过该试剂盒测得血清及血浆样本参考区间均<0.3 ng/mL。临床验证结果表明该试剂盒与罗氏Elecsys S100检测试剂盒的测定结果具有高度一致性(Kappa=0.9061>0.80),符合标准。结论:该试剂盒可快捷、准确、定量检测血清中S100B蛋白浓度,为神经类疾病、自身免疫病性疾病、脑血管疾病等的诊断与治疗提供了参考。

我国免疫分析仪发展现状与趋势研究

免疫分析技术作为疾病分析的重要手段,一直是生命科学领域研究的重点。近些年随着科学技术的不断发展,免疫诊断已逐渐成为体外诊断行业最大的细分领域。免疫分析仪作为免疫诊断的定量分析仪器,其发展规模、技术水平影响着免疫诊断行业高质量快速发展的程度。本文概述了免疫分析仪行业的发展现状,分析了各细分领域的注册情况以及竞争格局,总结了免疫分析仪行业存在的问题,并对行业的未来发展趋势进行了展望。

全自动酶标免疫分析仪的技术原理与故障案例分析

分析全自动酶标免疫分析仪的技术原理及典型故障案例,以提升全自动酶标免疫分析仪的使用效果。通过微粒子酶免疫分析(MEIA)技术完成酶免试验,以主定标、标准定标、定性定标及定标液修正为全自动酶标免疫分析仪的定标方式,提升酶免试验分析精度。通过分析全自动酶标免疫分析仪使用中遇到的洗板机、开机初始化报警、启动软盘、加样臂和滤光器等典型故障案例,提出故障解决应对措施,为全自动酶标免疫分析仪后期维修与管理提供参考。

干式免疫荧光定量分析法检测降钙素原与血培养结果的关系研究

目的分析与讨论干式免疫荧光定量分析法检测血培养、降钙素原(PCT)的关系和价值。方法筛选2021年1月至2023年2月64例血流感染(BSI)患者为研究对象,均检验PCT水平及血培养,对血培养阴性和阳性结果患者PCT水平对比,同时分析阳性患者病原菌分布情况,对比不同病原菌感染患者PCT指标间的差异。结果64例患者经血培养检验,12例患者结果呈阳性,占18.75%,52例阴性,占81.25%;血培养结果为阳性患者PCT水平高于阴性者,差异有统计学意义(P<0.05),12例血培养阳性患者中,发现病原菌以革兰阴性菌占比最高,为50.00%(6/12),其次是革兰氏阳性菌33.33%(4/12)与真菌16.67%(2/12);不同病原菌患者PCT水平经对比差异有统计学意义(P<0.05),且革兰氏阴性菌患者PCT水平高于革兰氏阳性菌与真菌的患者,差异有统计学意义(P<0.05)。结论PCT对诊断血流具有重要意义,并且快速简单,并不能准确确定病原体,可联合使用PCT与血培养,血培养弥补了PCT中的不足,从而可作为诊断血流感染最有价值检测方法。

Determination of theophylline concentration in serum by chemiluminescent immunoassay

Objective: This study aimed to establish chemiluminescent immunoassay (CLIA) for quantitative determination of theophylline levels in human serum. Methods: To measure the concentration of theophylline (n=122) and evaluate the assay.Results: The linear range of the CLIA method was 0.51～40 mg/L (Y=1.02X+0.44, r=0.995). The intra and inter CV (coefficient variance) of CLIA were 3.20% and 3.57%, respectively. The average recovery rate was 102.3%. This method was free from interference by brilirubin (＜200 μmol/L), hemoglobin (＜10 g/L), and triglycerides (＜15 mmol/L). Conclusion: This method is simple, convenient and precise for clinical pharmacokinetics study oftheophylline.

Preliminary Study of the CAS-LIBB Single-Particle Microbeam Ⅱ Endstation: Ⅰ. Proposed Multi-Dimensional Quantitative Fluorescence Microscopy

Single-particle microbeam as a powerful tool can open a research field to find answers to many enigmas in radiobiology. A single-particle microbeam facility has been constructed at the Key Laboratory of Ion Beam Bioengineering （LIBB）, Chinese Academy of Sciences （CAS）, China. However there has been less research activities in this field concerning the original process of the interaction between low-energy ions and complicated organisms. To address this challenge, an in situ multi-dimensional quantitative fluorescence microscopy system combined with the CAS-LIBB single-particle microbeam II endstation is proposed. In this article, the rationale, logistics and development of many aspects of the proposed system are discussed.

Improved detection Of the MUC1 cancer antigen CA 15-3 by ALYGNSA fluorimmunoassay

Breast cancer is the second leading cause of cancerrelated deaths in women worldwide;a prime cancer biomarker to aid in the diagnosis, directed treatment, clinical management, and reoccurrence of this cancer is a MUC1 peptide fragment: cancer antigen 15-3 (CA 15-3). Herein, an immuno-fluorescence assay for CA 15-3 was developed;this ALYGNSA system consists of a protein biolinker (Protein G’) adsorbed onto Poly (methyl methacrylate) (PMMA). The unique interaction of Protein G’ with PMMA, a thermo-plastic polymer has been demonstrated to improve human IgG capture antibody alignment/ orientation and result in greater assay sensitivity. Indeed a previous report (HEALTH 1 325 - 329, 2009) on the shed extracellular domain of HER-2/neu revealed a 10-fold increase in sensitivity of the ALYGSNA assay over a control ELISA assay. Results from this ALYGNSA assay study revealed that a 16-fold increase in detection (≤0.94 U/mL) of CA 15-3 was found in comparison to a commercial control ELISA kit (≤15 U/mL). In conclusion, this enhanced sensitivity of the ALYGNSA assay for CA 15-3, may provide insights into the role/function of this biomarker in normal, as well as, breast cancer and other epithelial cancers.

Intense Long-Lived Fluorescence of 1,6-Diphenyl-1,3,5-Hexatriene: Emission from the S₁-State Competes with Formation of O₂Contact Charge Transfer Complex

The fluorescence kinetics of 1,6-diphenyl-1,3,5-hexatriene (DPH) dissolved in cyclohexane was investigated as a function of temperature, concentration and 355 nm excitation pulse energy. At concentrations above 2.5 μM and excitation energies above 1 mJ a long-lived, very intense emission, which appears within less than 5 ns and lasts up to 70 ns, is observed. During the first 50 ns the decay does not follow an exponential but rather a linear behaviour. In oxygen saturated solutions the long-lived emission is suppressed and solely short-lived fluorescence with τ 1-state and competes with the formation of DPH-O2 contact charge-transfer complexes and intersystem crossing which both quench the fluorescence. Our investigations show that even the small amount of oxygen dissolved in nitrogen saturated solutions has a distinct influence on the fluorescence kinetics of DPH.