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Feng T, Song X, Wang W, Xu K, Wang S, Zhang N, Li Y, Ma H, Wei Q. High-bioactivity microfluidic immunosensing platform for electrochemiluminescence determination of CYFRA 21-1 with the introduction of Fe 3O 4@Cu@Cu 2O. Mikrochim Acta 2022; 189:336. [PMID: 35978171 DOI: 10.1007/s00604-022-05436-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 07/27/2022] [Indexed: 11/28/2022]
Abstract
Relying on the electrochemiluminescence (ECL) and microfluidic technology, an immunosensor chip with high bioactivity was designed for sensitive determination of cytokeratin 19 fragment 21-1 (CYFRA 21-1). The mesoporous nanomaterial Fe3O4@Cu@Cu2O as the co-reaction accelerator was used to catalyze the S2O82- to produce more SO4•- to achieve the amplification of the ECL signal. In fact, the generating of SO4•- could not only be done with the aid of the reversible cycles of Fe2+ and Fe3+ and Cu+ and Cu2+, but could be achieved also through the catalase-like function of Fe3O4. What is more, it has also been proved that Fe3O4@Cu@Cu2O exhibited better catalytic performance than single Fe3O4, Cu2O, and Cu@Cu2O, which supported its application in this system. In addition, a portable microfluidic immunosensor chip for CYFRA 21-1-sensitive determination was assembled, which showed high selectivity, sensitivity, and strong universality in clinical cancer screening and diagnosis. It should be noted that HWRGWVC (HWR) was introduced as the antibody fixator to improve the incubation and binding efficiency of the antibody, which increased the ECL intensity and improved the sensitivity of the immunosensor. This strategy provided a new idea for cancer identification and diagnosis in clinical medicine.
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Affiliation(s)
- Tao Feng
- Collaborative Innovation Center for Green Chemical Manufacturing and Accurate Detection, Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, Shandong, China
| | - Xianzhen Song
- Collaborative Innovation Center for Green Chemical Manufacturing and Accurate Detection, Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, Shandong, China
| | - Wei Wang
- Logistics Management Center of Yantai Customs District, Yantai, Shandong, China
| | - Kun Xu
- Collaborative Innovation Center for Green Chemical Manufacturing and Accurate Detection, Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, Shandong, China
| | - Shoufeng Wang
- Collaborative Innovation Center for Green Chemical Manufacturing and Accurate Detection, Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, Shandong, China
| | - Nuo Zhang
- Collaborative Innovation Center for Green Chemical Manufacturing and Accurate Detection, Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, Shandong, China.,Shandong University of Technology, West Campus No.12 Zhangzhou Road, Zibo, 255049, Shandong, China
| | - YuYang Li
- Collaborative Innovation Center for Green Chemical Manufacturing and Accurate Detection, Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, Shandong, China
| | - Hongmin Ma
- Collaborative Innovation Center for Green Chemical Manufacturing and Accurate Detection, Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, Shandong, China.
| | - Qin Wei
- Collaborative Innovation Center for Green Chemical Manufacturing and Accurate Detection, Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, Shandong, China.
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Fukuyama M, Nakamura A, Nishiyama K, Imai A, Tokeshi M, Shigemura K, Hibara A. Noncompetitive Fluorescence Polarization Immunoassay for Protein Determination. Anal Chem 2020; 92:14393-14397. [DOI: 10.1021/acs.analchem.0c02300] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Mao Fukuyama
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai 980-8577, Japan
| | - Ayano Nakamura
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, Kita 13, Nishi 8, Kita-ku, Sapporo 060-8628, Japan
| | - Keine Nishiyama
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, Kita 13, Nishi 8, Kita-ku, Sapporo 060-8628, Japan
| | - Ayuko Imai
- Tianma Japan, Ltd., Shin-Kawasaki Mitsui Building West Tower 28F, 1-1-2, Kashimada, Saiwai-ku, Kawasaki, Kanagawa 212-0058, Japan
| | - Manabu Tokeshi
- Division of Applied Chemistry, Faculty of Engineering, Hokkaido University, Kita 13, Nishi 8, Kita-ku, Sapporo 060-8628, Japan
| | - Koji Shigemura
- Tianma Japan, Ltd., Shin-Kawasaki Mitsui Building West Tower 28F, 1-1-2, Kashimada, Saiwai-ku, Kawasaki, Kanagawa 212-0058, Japan
| | - Akihide Hibara
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai 980-8577, Japan
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Samartino L, Gregoret R, Gall D, Nielsen K. Fluorescence polarization assay: application to the diagnosis of bovine brucellosis in Argentina. JOURNAL OF IMMUNOASSAY 1999; 20:115-26. [PMID: 10458638 DOI: 10.1080/01971529909349347] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
A homogeneous fluorescence polarization assay (FPIA) for detection of bovine antibody to Brucella abortus was validated in Argentina Sera were defined based on their reactivity in the buffered antigen plate agglutination test (BPAT) and the competitive enzyme immunoassay (CELISA). Sera negative in these tests were collected from farms without evidence of brucellosis (n=733). Sera positive in the two tests were collected from cattle on farms from which B. abortus was isolated from at least one animal (n=1039). Sera from cattle vaccinated 26, 89, 240 and 272 days previously with B. abortus strain 19 were collected and tested. A cut-off value of 87 mP was determined for the FPIA, resulting in relative sensitivity and specificity values of 98.1 and 99.6%. The specificity for B. abortus strain 19 vaccinated cattle was 64.9% (26 days post vaccination, DPV), 92.1% (89 DPV), 98.6% (242 DPV) and 97.1% (272 DPV). These values were compared to those obtained with the BPAT, the CELISA, the indirect ELISA, the complement fixation test and the 2-mercaptoethanol agglutination test. Sera from 18 cattle which were vaccinated and revaccinated with B. abortus strain 19 were also tested by the same assays and the FPIA was found to be 100% specific. The use of the FPIA as a diagnostic test for brucellosis is discussed.
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Affiliation(s)
- L Samartino
- CICV-INTA, Instituto de Patholobiologia, Buenos Aires, Argentina
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4
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Song X, Swanson BI. Direct, ultrasensitive, and selective optical detection of protein toxins using multivalent interactions. Anal Chem 1999; 71:2097-107. [PMID: 10366891 DOI: 10.1021/ac981145f] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Three highly sensitive, selective, and reagent-free optical signal transduction methods for detection of polyvalent proteins have been developed by directly coupling distance-dependent fluorescence self-quenching and/or resonant-energy transfer to the protein-receptor binding events. The ganglioside GM1, as the recognition unit for cholera toxin (CT), was covalently labeled with fluorophores and then incorporated into a biomimetic membrane surface. The presence of CT with five binding sites for GM1 causes dramatic change for the fluorescence of the labeled GM1. (1) In the scheme using fluorescence self-quenching as a signal-transduction mechanism, the fluorescence intensity drops significantly as a result of aggregation of the fluorophore-labeled GM1 on a biomimetic surface. (2) By labeling GM1 with a fluorescence energy transfer pair, aggregation of the labeled GM1 results in a decrease in donor fluorescence and an increase in acceptor fluorescence, providing a unique signature for selective protein-receptor binding. (3) In the third scheme, using the biomimetic surface as part of signal transduction and combining both fluorescence self-quenching and energy-transfer mechanisms to enhance the signal transduction, a signal amplification was achieved. The detection systems can reliably detect less than 0.05 nM CT with fast response (less than 5 min). This approach can easily be adapted to any biosensor scheme that relies on multiple receptors or co-receptors. The methods can also be applied to investigate the kinetics and thermodynamics of the multivalent interactions.
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Affiliation(s)
- X Song
- Chemical Science and Technology Division, Los Alamos National Laboratory, New Mexico 87545, USA.
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5
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Dajer A, Luna-Martínez E, Zapata D, Villegas S, Gutiérrez E, Peña G, Gurría F, Nielsen K, Gall D. Evaluation of a fluorescence-polarization assay for the diagnosis of bovine brucellosis in México. Prev Vet Med 1999; 40:67-73. [PMID: 10343334 DOI: 10.1016/s0167-5877(99)00004-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
A homogeneous fluorescence-polarization assay (FPA) was used for the serological diagnosis of bovine brucellosis in México. The assay uses O-polysaccharide prepared from Brucella abortus lipoplysaccharide (20-30 kDa) conjugated with fluorescein isothiocyanate as a tracer. To measure the fluorescence polarization, a FPM-1 fluorescence-polarization analyzer was used with the procedure described by Nielsen et al. (1996b). A cut-off value of 90 millipolarization (mP) units was used for testing 560 bovine sera from different areas of México. (305 positive sera and 255 negative sera according to the complement fixation test; CFT.) Some were tested with the Rose Bengal plate (RB) test (n = 490) and some with the rivanol-agglutination (RIV) test (n = 190). Sensitivities were 98.3%, 99.3% and 99.0%, and specificities were 68.8%, 55.4% and 96.9%, respectively, for RB, RIV and FPA. The FPA gave a kappa coefficient of agreement with respect to CFT of 0.96, while RB and RIV (relative to the CFT) gave coefficients of 0.70 and 0.61, respectively. Finally, ROC analysis suggested a cut-off value which agreed with the one recommended in the test procedure. We concluded that FPA is a suitable test to be used instead of the CFT in Mexican conditions.
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Affiliation(s)
- A Dajer
- Universidad Autónoma de Yucatán, Facultad de Medicina Veterinaria y Zootecnia, Depto. de Inmunología. km., Yucatan, Mexico.
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6
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Guo XQ, Castellano FN, Li L, Lakowicz JR. Use of a long-lifetime Re(I) complex in fluorescence polarization immunoassays of high-molecular-weight analytes. Anal Chem 1998; 70:632-7. [PMID: 9470490 PMCID: PMC6943338 DOI: 10.1021/ac970827k] [Citation(s) in RCA: 120] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
We describe a new class of fluorescence polarization immunoassays based on the luminescence from a Re(I) metal-ligand complex. Re(I) complexes are extremely photostable and possess useful photophysical properties including long lifetimes, high quantum yields, and high emission polarization in the absence of rotational diffusion. In the present study, a conjugatable, highly luminescent Re(I) metal-ligand complex, [Re(bcp)(CO)3(4-COOHPy)](ClO4), where bcp is 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline and 4-COOHPy is isonicotinic acid, has been evaluated for use in fluorescence polarization immunoassays (FPIs) with high-molecular-weight antigens. This Re(I) complex (Re) displays highly polarized emission (with a maximum anisotropy near 0.3) in the absence of rotational diffusion and a long average lifetime (2.7 microseconds) when bound to human serum albumin (HSA) in oxygenated aqueous solution. The emission polarization of the Re-HSA conjugate is sensitive to the binding of anti-HSA, resulting in a significant increase in anisotropy. The labeled HSA was also used in a competition immunoassay where unlabeled HSA was also used as an antigen. These experimental results, combined with theoretical predictions, demonstrate the potential of this Re(I) metal-ligand complex as a luminescence probe in FPIs of high-molecular-weight analytes (10(5)-10(8) Da).
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Affiliation(s)
- X Q Guo
- Department of Biochemistry & Molecular Biology, University of Maryland School of Medicine, Baltimore 21201, USA
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Szmacinski H, Terpetschnig E, Lakowicz JR. Synthesis and evaluation of Ru-complexes as anisotropy probes for protein hydrodynamics and immunoassays of high-molecular-weight antigens. Biophys Chem 1996; 62:109-20. [PMID: 8962474 PMCID: PMC7395961 DOI: 10.1016/s0301-4622(96)02199-0] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We investigated three unsymmetrical Ru-complexes, namely [Ru(bpy)2 (phen-ITC)]2+, [Ru(bpy)2(dcbpy)] and [Ru(bpy)2(mcbpy)]+ for use as probes for rotational diffusion and in immunoassays of high-molecular-weight antigens. For this purpose we synthesized reactive forms of these metal-ligand complexes and conjugated them to human serum albumin (HSA). The maximal anisotropies (r0) for the HSA-bound forms in frozen solution are 0.23, 0.17 and 0.14 for the (dcbpy), (mcbpy) and (phen-ITC) derivatives, respectively. The activated Ru metal-ligand complexes have either one or two NHS-esters or an isothiocyanate group as the reactive moiety. The usefulness of these complexes in immunoassays was determined by titration of the labeled HSA with polyclonal anti-HSA. The highest steady state anisotropy (r) values (0.190) were observed for the [Ru(bpy)2(dcbpy)]-labeled HSA on titration with polyclonal antibody. However, a relative increase in the steady state anisotropy (r/r0) on titration with polyclonal antibody was found for the phen-ITC probe (96%), as compared to the dcbpy (83%) or mcbpy (79%) derivatives. These findings were confirmed by time-resolved frequency-domain measurements. In particular the higher mean correlation times calculated for the phen-ITC derivative suggests reduced local probe motion for this probe when bound to HSA as compared to the (mcbpy) and (dcbpy) conjugates.
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Affiliation(s)
- H Szmacinski
- University of Maryland at Baltimore, Department of Biochemistry and Molecular Biology 21201, USA
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8
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Hirata MH, Sackett D, Hirata RD, Nguyen NY. Human interferon-alpha receptor: identification of the region involved in binding to interferon-alpha B. J Interferon Cytokine Res 1996; 16:845-52. [PMID: 8910770 DOI: 10.1089/jir.1996.16.845] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Three polypeptides comprising amino acids 1-102, 93-260, and 261-410 of the extracellular domain of the human interferon-alpha receptor HuIFN-alpha R (Uzé, G., Lutfalla, G., and Gresser, I. Cell 1990; 60:225-234) have been expressed in Escherichia coli. The polypeptides were sequestered within bacterial inclusion bodies. Inclusion body material was solubilized by 8 M urea, and the polypeptides were purified by gel filtration or histidine tag-based affinity chromatography. Overall recovery of each purified and refolded polypeptide was approximately 0.5-0.8 mg/liter of cell culture. The polypeptides migrated as homogeneous monomers of 12 kDa, 22 kDa, and 17 kDa, respectively on reduced sodium dodecylsulfate polyacrylamide gel electrophoresis. The polypeptide fragments corresponding to amino acids 1-102, and 93-260 of the extracellular domain of HuIFN-alpha R lacked the ability to bind to IFN-alpha B and to inhibit its biologic activities. The polypeptide fragment corresponding to amino acids 261-410 of the receptor molecule inhibited the antiproliferative activity of IFN-alpha B and competed with the Daudi cell surface receptor for binding to this IFN-alpha species.
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Affiliation(s)
- M H Hirata
- Division of Cytokine Biology, Food and Drug Administration, Bethesda, MD 20892, USA
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9
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Nguyen NY, Sackett D, Hirata RD, Levy DE, Enterline JC, Bekisz JB, Hirata MH. Isolation of a biologically active soluble human interferon-alpha receptor-GST fusion protein expressed in Escherichia coli. J Interferon Cytokine Res 1996; 16:835-44. [PMID: 8910769 DOI: 10.1089/jir.1996.16.835] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The cDNA encoding the extracellular domain of the human interferon-alpha (IFN-alpha) receptor (Uzé, G., Lutfalla, G., and Gresser, I. Cell 1990;60:225-234) lacking the signal peptide has been expressed in Escherichia coli as a fusion protein with glutathione S-transferase. The fusion protein represented 12% of total bacterial proteins and was found exclusively within cytoplasmic inclusion bodies. Inclusion body material was completely solubilized by 8 M urea; 20% solubilization was achieved by cell lysis in the presence of 0.45% cholamidopropyl dimethylammoniol-propane sulfonate and 1% Triton X-100. The soluble fusion protein was purified by gel filtration and affinity chromatography. Overall recovery of affinity purified fusion protein was approximately 100-200 micrograms/liter of cell culture. The affinity purified and refolded fusion protein exhibited the expected amino terminal sequence and M(r) of 68,000 on reduced sodium dodecylsulfate gel electrophoresis. The protein reacted with antibodies specific for the cloned IFN-alpha receptor and inhibited the antiviral and antiproliferative activities of recombinant IFN-alpha B. We have demonstrated that the fusion protein binds to IFN-alpha B and competes with the cell surface receptor for binding to this IFN-alpha species.
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Affiliation(s)
- N Y Nguyen
- Division of Cytokine Biology, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD 20892, USA
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Nielsen K, Gall D, Jolley M, Leishman G, Balsevicius S, Smith P, Nicoletti P, Thomas F. A homogeneous fluorescence polarization assay for detection of antibody to Brucella abortus. J Immunol Methods 1996; 195:161-8. [PMID: 8814332 DOI: 10.1016/0022-1759(96)00116-0] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A homogeneous fluorescence polarization (FP) assay (FPA) was developed for detection of antibody in bovine sera to Brucella abortus. The assay used O-polysaccharide prepared from B. abortus lipopolysaccharide in the molecular weight range of 20-30 kDa which was conjugated with fluorescein isothiocyanate and used as a tracer. Fluorescence polarization was measured with a FPM-1 fluorescence polarization analyzer. Sample (20 microliters) was added to 2.0 ml of diluent buffer at ambient temperature. A serum blank reading was taken and tracer (10 microliters) to yield approx. 1.5 nM fluorescein equivalents was added. The FP of the tracer was determined after a period of greater than 2 min. A positive reaction was indicated by a significant elevation of the FP reading over the negative control. In a blind study, 9480 bovine sera were tested in addition to sets of four controls which were included with each lot of 100 samples tested. The controls were a strong positive, a weak positive, a negative and a serum derived from a B. abortus strain 19 vaccinated cow. Test sera included 8669 sera from Canadian cattle which were negative by routine serological tests, 561 sera from cows from which B. abortus had been isolated either from tissues or milk and 250 sera from cattle previously vaccinated with B. abortus strain 19 at various times. One lot of O-polysaccharide tracer was used for all tests. The initial cut-off for negative samples in the fluorescence polarization assay was set at 107.2 mP. This resulted in a sensitivity estimate of 98.1 +/- 1.1% and the specificity was 99.8 +/- 0.09%. After decoding the samples and retesting false positive and negative reactions, the sensitivity estimate was 98.5 +/- 1.0% and the specificity was 100%. It became evident that the initial cut-off value was set too high and, using ROC analysis, a cut-off of 90 mP increased the sensitivity to 99.02% while the specificity decreased to 99.96%. Of the 250 sera from vaccinated cattle, 248 were negative giving a point specificity value of 99.2%.
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Affiliation(s)
- K Nielsen
- Agriculture and Agri-Food Canada, Animal Diseases Research Institute, Nepean, Ont., Canada
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Terpetschnig E, Szmacinski H, Lakowicz JR. Fluorescence polarization immunoassay of a high-molecular-weight antigen based on a long-lifetime Ru-ligand complex. Anal Biochem 1995; 227:140-7. [PMID: 7668374 PMCID: PMC6908827 DOI: 10.1006/abio.1995.1263] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We describe a new class of fluorescence polarization immunoassays based on the luminescence from an asymmetrical Ru-ligand complex. We found that such a complex displays larger polarization values than those of comparable symmetrical complexes and appear to be highly photostable in aqueous solution. We synthesized a conjugatable Ru-ligand complex, which was used to label human serum albumin (HSA) as the antigen. The Ru-ligand complex displays a long decay time near 400 ns when covalently linked to proteins. We found that the steady-state polarization of labeled HSA was sensitive to binding of anti-HSA, resulting in a 200% increase in polarization. The labeled HSA was also used in a competitive format using unlabeled HSA as the antigen. The time-resolved anisotropy decays demonstrate increased correlation times for labeled HSA in the presence of anti-HSA, an effect which was partially reversed in the presence of unlabeled HSA. These results demonstrate the potential of the metal-ligand complexes to be used in the fluorescence polarization immunoassay of high-molecular-weight analytes. The use of such metal-ligand complexes enable fluorescence polarization immunoassays which bypass the usual limitation to low-molecular-weight antigens, which is a consequence of the 2-5 ns decay time of the previously used fluorophores.
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Affiliation(s)
- E Terpetschnig
- Department of Biological Chemistry, University of Maryland at Baltimore, School of Medicine 21201, USA
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Tatsu Y, Yamamura S, Yamamoto H, Yoshikawa S. Fluorimetry of haemolyis of red blood cells by catalytic reaction of leaked haemoglobin: Application to homoegeneous fluorescence immunoassay. Anal Chim Acta 1993. [DOI: 10.1016/0003-2670(93)80564-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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13
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Huang PY, Lee CS, Heath C, Banik G. Direct and homogeneous immunoassay for IgG analyses. Biotechnol Bioeng 1992; 40:913-8. [DOI: 10.1002/bit.260400807] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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