1
|
Kaya T, Nagatoishi S, Nagae K, Nakamura Y, Tsumoto K. Highly sensitive biomolecular interaction detection method using optical bound/free separation with grating-coupled surface plasmon field-enhanced fluorescence spectroscopy (GC-SPFS). PLoS One 2019; 14:e0220578. [PMID: 31369601 PMCID: PMC6675060 DOI: 10.1371/journal.pone.0220578] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 07/18/2019] [Indexed: 01/06/2023] Open
Abstract
Grating-coupled surface plasmon field-enhanced fluorescence spectroscopy (GC-SPFS) with optical bound/free (B/F) separation technique was developed by employing a highly directional fluorescence with polarization of surface plasmon-coupled emission (SPCE) to realize highly sensitive immunoassay regardless of the ligand affinity. A highly sensitive immunoassay system with GC-SPFS was constructed using a plastic sensor chip reproducibly fabricated in-house by nanoimprinting and applied to the quantitative detection of an anti-lysozyme single-domain antibody (sdAb), to compare conventional washing B/F separation with optical B/F separation. Differences in the affinity of the anti-lysozyme sdAb, induced by artificial mutation of only one amino acid residue in the variable domain were attributed to higher sensitivity than that of the conventional Biacore surface plasmon resonance (SPR) system. The detection limit (LOD; means of six replicates of the zero standard plus three standard deviations) of the GC-SPFS immunoassay with optical B/F separation, was estimated to be 1.2 ng/ml with the low-affinity ligand (mutant sdAb Y52A: KD level was of the order of 10−7 ~ 10−6 M) and was clearly improved as compared to that (LOD: 9.4 ng/ml) obtained with the conventional washing B/F separation. These results indicate that GC-SPFS with the optical B/F separation technique offers opportunities to re-evaluate low-affinity biomaterials that are neither fully utilized nor widespread, and could facilitate the creation of novel and innovative methods in drug and diagnostic development.
Collapse
Affiliation(s)
- Takatoshi Kaya
- Corporate R&D Headquarters, Konica Minolta, Inc., Hino-shi, Tokyo, Japan
- * E-mail: (TK); (KT)
| | - Satoru Nagatoishi
- Institute of Medical Science, the University of Tokyo, Tokyo, Japan
- Department of Bioengineering, School of Engineering, the University of Tokyo, Hongo Bunkyo-ku, Tokyo, Japan
| | - Kosuke Nagae
- Corporate R&D Headquarters, Konica Minolta, Inc., Hino-shi, Tokyo, Japan
| | - Yukito Nakamura
- Corporate R&D Headquarters, Konica Minolta, Inc., Hino-shi, Tokyo, Japan
| | - Kohei Tsumoto
- Institute of Medical Science, the University of Tokyo, Tokyo, Japan
- Department of Bioengineering, School of Engineering, the University of Tokyo, Hongo Bunkyo-ku, Tokyo, Japan
- * E-mail: (TK); (KT)
| |
Collapse
|
2
|
Tran NHT, Trinh KTL, Lee JH, Yoon WJ, Ju H. Reproducible Enhancement of Fluorescence by Bimetal Mediated Surface Plasmon Coupled Emission for Highly Sensitive Quantitative Diagnosis of Double-Stranded DNA. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2018; 14:e1801385. [PMID: 30003662 DOI: 10.1002/smll.201801385] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 06/05/2018] [Indexed: 05/27/2023]
Abstract
Plasmonic enhancement of fluorescence from SYBR Green I conjugated with a double-stranded DNA (dsDNA) amplicon is demonstrated on polymerase chain reaction (PCR) products. Theoretical computation leads to use of the bimetallic (Au 2 nm-Ag 50 nm) surface plasmons due to larger local fields (higher quality factors) than monometallic (Ag or Au) ones at both dye excitation and emission wavelengths simultaneously, optimizing fluorescence enhancement with surface plasmon coupled emission (SPCE). Two kinds of reverse Kretschmann configurations are used, which favor, in signal-to-noise ratio, a fluorescence assay that uses optically dense buffer such as blood plasma. The fluorescence enhancement (12.9 fold at maximum) with remarkably high reproducibility (coefficient of variation (CV) < 1%) is experimentally demonstrated. This facilitates credible quantitation of enhanced fluorescence, however unlikely to obtain by localized surface plasmons. The plasmon-induced optical gain of 46 dB due to SPCE-active dye molecules is also estimated. The fluorescence enhancement technologies with PCR enables LOD of the dsDNA template concentration of ≈400 fg µL-1 (CV < 1%), the lowest ever reported in DNA fluorescence assay to date. SPCE also reduces photobleaching significantly. These technologies can be extended for a highly reproducible and sufficiently sensitive fluorescence assay with small volumes of analytes in multiplexed diagnostics.
Collapse
Affiliation(s)
- Nhu Hoa Thi Tran
- Department of Nano-Physics, Gachon University, Seongnam, 13120, Republic of Korea
- Gachon Bionano Research Institute, Gachon University, Seongnam, 13120, Republic of Korea
| | - Kieu The Loan Trinh
- Department of BioNano Technology, Gachon University, Seongnam, 13120, Republic of Korea
| | - Jun-Ho Lee
- Department of Nano-Physics, Gachon University, Seongnam, 13120, Republic of Korea
- Laser & Opto-electronics Team, Korea Electronics Technology Institute (KETI), Seongnam, 13509, Republic of Korea
| | - Won Jung Yoon
- Department of Chemical and BioEngineering, Gachon University, Seongnam, 13120, Republic of Korea
| | - Heongkyu Ju
- Department of Nano-Physics, Gachon University, Seongnam, 13120, Republic of Korea
- Gachon Bionano Research Institute, Gachon University, Seongnam, 13120, Republic of Korea
- Neuroscience Institute, Gil Hospital, Incheon, 405-760, Republic of Korea
| |
Collapse
|
3
|
Zhu L, Badugu R, Zhang D, Wang R, Descrovi E, Lakowicz JR. Radiative decay engineering 8: Coupled emission microscopy for lens-free high-throughput fluorescence detection. Anal Biochem 2017; 531:20-36. [PMID: 28527910 DOI: 10.1016/j.ab.2017.05.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Revised: 05/13/2017] [Accepted: 05/16/2017] [Indexed: 12/13/2022]
Abstract
Fluorescence spectroscopy and imaging are now used throughout the biosciences. Fluorescence microscopes, spectrofluorometers, microwell plate readers and microarray imagers all use multiple optical components to collect, redirect and focus the emission onto single point or array imaging detectors. For almost all biological samples, except those with regular nanoscale features, emission occurs in all directions. With the exception of complex microscope objectives with large collection angles (NA ≤ 0.5), all these instruments collect only a small fraction of the total emission. Because of the increasing knowledge base on fluorophores within near-field (<200 nm) distances from plasmonic and photonic structures we can anticipate the development of compact devices in which the sample to be detected is located directly on solid state detectors such as CCDs or CMOS cameras. Near-field interactions of fluorophores with metallic or dielectric multi-layer structures (MLSs) can capture a large fraction of the total emission. Depending on the composition and dimensions of the MLSs, the spatial distribution of the sample emission results in distinct optical patterns on the detector surface. With either plain glass slides or MLSs the most commonly used front focal plane (FFP) images reveal the x-y spatial distribution of emission from the sample. Another approach, which is often used with two or three-dimensional nanostructures, is back focal plane (BFP) imaging. The BFP images reveal the angular distribution of the emission. The FFP and BFP images occur at certain distances from the sample which is determined by the details of the optical components. Obtaining these images requires multiple optical components and distances which are too large for the compact devices. For devices described in this paper, the images will be detected at a fixed distance between the sample and some arbitrary distance below the MLS which is determined by the geometry and thicknesses of the components. We refer to measurements at these locations as out-of-focal plane (OFP) imaging. Herein we describe a method to measure the optical fields at micron and multi-micron distances below the MLS, which will represent the images seen by an optically coupled array detector. The possibility of sub-surface optical images is illustrated using five different multi-layer structures. This is accomplished using an optical configuration which allows measurement at a front focal plane (FFP), back focal plane (BFP) or any OFP locations. Our OFP imaging method provides a link between the FFP images which reveals the surface distribution of fluorophores with the BFP images that reveal the angular distribution of emission. This linkage can be useful when examining structures which have nanoscale features due to fluorescence or leakage radiation from nanostructures.
Collapse
Affiliation(s)
- Liangfu Zhu
- Institute of Photonics, Department of Optics and Optical Engineering, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Ramachandram Badugu
- University of Maryland School of Medicine, Department of Biochemistry and Molecular Biology, Center for Fluorescence Spectroscopy, Baltimore, Md 21201, USA
| | - Douguo Zhang
- Institute of Photonics, Department of Optics and Optical Engineering, University of Science and Technology of China, Hefei, Anhui, 230026, China.
| | - Ruxue Wang
- Institute of Photonics, Department of Optics and Optical Engineering, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Emiliano Descrovi
- Department of Applied Science and Technology, Polytechnic University of Turin, Corso Duca degli Abruzzi 24, 10129 Turin, Italy
| | - Joseph R Lakowicz
- University of Maryland School of Medicine, Department of Biochemistry and Molecular Biology, Center for Fluorescence Spectroscopy, Baltimore, Md 21201, USA.
| |
Collapse
|
4
|
Mbomson IG, Tabor S, Lahiri B, Sharp G, McMeekin SG, De La Rue RM, Johnson NP. Asymmetric split H-shape nanoantennas for molecular sensing. BIOMEDICAL OPTICS EXPRESS 2017; 8:395-406. [PMID: 28101426 PMCID: PMC5231308 DOI: 10.1364/boe.8.000395] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 12/14/2016] [Accepted: 12/14/2016] [Indexed: 05/20/2023]
Abstract
In this paper we report on a very sensitive biosensor based on gold asymmetric nanoantennas that are capable of enhancing the molecular resonances of C-H bonds. The nanoantennas are arranged as arrays of asymmetric-split H-shape (ASH) structures, tuned to produce plasmonic resonances with reflectance double peaks within the mid-infrared vibrational resonances of C-H bonds for the assay of deposited films of the molecule 17β-estradiol (E2), used as an analyte. Measurements and numerical simulations of the reflectance spectra have enabled an estimated enhancement factor on the order of 105 to be obtained for a thin film of E2 on the ASH array. A high sensitivity value of 2335 nm/RIU was achieved, together with a figure of merit of approximately 8. Our experimental results were corroborated using numerical simulations for the C-H stretch vibrational resonances from the analyte, superimposed on the plasmonic resonances of the ASH nanoantennas.
Collapse
Affiliation(s)
- I. G. Mbomson
- School of Engineering, University of Glasgow, Glasgow, G12 8LT, UK
| | - S. Tabor
- School of Engineering, University of Glasgow, Glasgow, G12 8LT, UK
| | - B. Lahiri
- School of Engineering, University of Glasgow, Glasgow, G12 8LT, UK
| | - G. Sharp
- School of Engineering, University of Glasgow, Glasgow, G12 8LT, UK
| | - S. G. McMeekin
- School of Computing and Engineering, Glasgow Caledonian University, Glasgow, G4 0BA, UK
| | - R. M. De La Rue
- School of Engineering, University of Glasgow, Glasgow, G12 8LT, UK
| | - N. P. Johnson
- School of Engineering, University of Glasgow, Glasgow, G12 8LT, UK
| |
Collapse
|
5
|
Tawa K, Kondo F, Sasakawa C, Nagae K, Nakamura Y, Nozaki A, Kaya T. Sensitive detection of a tumor marker, α-fetoprotein, with a sandwich assay on a plasmonic chip. Anal Chem 2015; 87:3871-6. [PMID: 25719730 DOI: 10.1021/ac504642j] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Two types of plasmonic silver- and gold-coated grating biosensor chips (plasmonic chip) were applied in the detection of α-fetoprotein (AFP) with a sandwich imunoassay and surface plasmon field-enhanced fluorescence. On the plasmonic chip, unlabeled marker in the sandwich immunoassay was first quantitatively detected over a wide range between 10(-12) and 10(-8) g/mL. The affinity constants between AFP and anti-AFP antibody, which were obtained by fitting the experimental data to the Langmuir isotherm adsorption curve, were 1 × 10(8) g(-1) mL regardless of the kind of metal in the plasmonic chips. Although the fluorescence intensity on the silver plasmonic chip was 5 times larger than that on the gold plasmonic chip, the limit of detection (LOD) was on the order of 10(-11) g/mL and not improved with a silver plasmonic chip. Herein, we used a new setup that generated less dispersions of both the fluorescence intensity for nonspecific adsorption and the background (optical blank) signal and improved the LOD of AFP to 4 pg/mL (55 fM) with the silver plasmonic chip. With the highly sensitive detection in the sandwich immunoassay, the development of a plasmonic chip for clinical diagnosis by a blood test is promising.
Collapse
Affiliation(s)
- Keiko Tawa
- †Health Research Institute, AIST, 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577, Japan.,§Department of Chemistry, Graduate School of Science and Technology, Kwansei Gakuin University, Sanda, Hyogo 669-1337, Japan
| | - Fusanori Kondo
- †Health Research Institute, AIST, 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577, Japan.,§Department of Chemistry, Graduate School of Science and Technology, Kwansei Gakuin University, Sanda, Hyogo 669-1337, Japan
| | - Chisato Sasakawa
- †Health Research Institute, AIST, 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577, Japan
| | - Kousuke Nagae
- ‡Konica Minolta Inc., No.1 Sakuramachi, Hino-shi, Tokyo 191-8511, Japan
| | - Yukito Nakamura
- ‡Konica Minolta Inc., No.1 Sakuramachi, Hino-shi, Tokyo 191-8511, Japan
| | - Akitoshi Nozaki
- ‡Konica Minolta Inc., No.1 Sakuramachi, Hino-shi, Tokyo 191-8511, Japan
| | - Takatoshi Kaya
- ‡Konica Minolta Inc., No.1 Sakuramachi, Hino-shi, Tokyo 191-8511, Japan
| |
Collapse
|
6
|
Abstract
Surface plasmon resonance (SPR) has found extensive applications in chemi-sensors and biosensors. Plasmons play different roles in different types of optical sensors. SPR transduces a signal in a colorimetric sensor through shifts in the spectral position and intensity in response to external stimuli. SPR can also concentrate the incident electromagnetic field in a nanostructure, modulating fluorescence emission and enabling plasmon-enhanced fluorescence to be used for ultrasensitive detection. Furthermore, plasmons have been extensively used for amplifying a Raman signal in a surface-enhanced Raman scattering sensor. This paper presents a review of recent research progress in plasmon-enhanced optical sensing, giving emphasis on the physical basis of plasmon-enhanced sensors and how these principles guide the design of sensors. In particular, this paper discusses the design strategies for nanomaterials and nanostructures to plasmonically enhance optical sensing signals, also highlighting the applications of plasmon-enhanced optical sensors in healthcare, homeland security, food safety and environmental monitoring.
Collapse
Affiliation(s)
- Ming Li
- Department of Mechanical and Aerospace Engineering, West Virginia University, Morgantown, WV 26506-6106, USA.
| | | | | |
Collapse
|
7
|
Cao SH, Cai WP, Liu Q, Li YQ. Surface plasmon-coupled emission: what can directional fluorescence bring to the analytical sciences? ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2012; 5:317-36. [PMID: 22524220 DOI: 10.1146/annurev-anchem-062011-143208] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Surface plasmon-coupled emission (SPCE) arose from the integration of fluorescence and plasmonics, two rapidly expanding research fields. SPCE is revealing novel phenomena and has potential applications in bioanalysis, medical diagnostics, drug discovery, and genomics. In SPCE, excited fluorophores couple with surface plasmons on a continuous thin metal film; plasmophores radiate into a higher-refractive index medium with a narrow angular distribution. Because of the directional emission, the sensitivity of this technique can be greatly improved with high collection efficiency. This review describes the unique features of SPCE. In particular, we focus on recent advances in SPCE-based analytical platforms and their applications in DNA sensing and the detection of other biomolecules and chemicals.
Collapse
Affiliation(s)
- Shuo-Hui Cao
- Department of Chemistry and Key Laboratory of Analytical Sciences, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | | | | | | |
Collapse
|
8
|
Gonzales AL, Earley S. Endogenous cytosolic Ca(2+) buffering is necessary for TRPM4 activity in cerebral artery smooth muscle cells. Cell Calcium 2012; 51:82-93. [PMID: 22153976 PMCID: PMC3265659 DOI: 10.1016/j.ceca.2011.11.004] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Revised: 10/28/2011] [Accepted: 11/14/2011] [Indexed: 10/14/2022]
Abstract
The melastatin transient receptor potential (TRP) channel, TRPM4, is a critical regulator of smooth muscle membrane potential and arterial tone. Activation of the channel is Ca(2+)-dependent, but prolonged exposures to high global Ca(2+) causes rapid inactivation under conventional whole-cell patch clamp conditions. Using amphotericin B perforated whole cell patch clamp electrophysiology, which minimally disrupts cytosolic Ca(2+) dynamics, we recently showed that Ca(2+) released from 1,2,5-triphosphate receptors (IP(3)R) on the sarcoplasmic reticulum (SR) activates TRPM4 channels, producing sustained transient inward cation currents (TICCs). Thus, Ca(2+)-dependent inactivation of TRPM4 may not be inherent to the channel itself but rather is a result of the recording conditions. We hypothesized that under conventional whole-cell configurations, loss of intrinsic cytosolic Ca(2+) buffering following cell dialysis contributes to inactivation of TRPM4 channels. With the inclusion of the Ca(2+) buffers ethylene glycol-bis(2-aminoethylether)-N,N,N',N'-tetraacetic acid (EGTA, 10mM) or bis-ethane-N,N,N',N'-tetraacetic acid (BAPTA, 0.1mM) in the pipette solution, we mimic endogenous Ca(2+) buffering and record novel, sustained whole-cell TICC activity from freshly-isolated cerebral artery myocytes. Biophysical properties of TICCs recorded under perforated and whole-cell patch clamp were nearly identical. Furthermore, whole-cell TICC activity was reduced by the selective TRPM4 inhibitor, 9-phenanthrol, and by siRNA-mediated knockdown of TRPM4. When a higher concentration (10mM) of BAPTA was included in the pipette solution, TICC activity was disrupted, suggesting that TRPM4 channels on the plasma membrane and IP(3)R on the SR are closely opposed but not physically coupled, and that endogenous Ca(2+) buffer proteins play a critical role in maintaining TRPM4 channel activity in native cerebral artery smooth muscle cells.
Collapse
Affiliation(s)
- Albert L Gonzales
- Vascular Physiology Research Group, Department of Biomedical Sciences Colorado State University Fort Collins, CO 80523-1617, USA
| | | |
Collapse
|
9
|
Tawa K, Cui X, Kintaka K, Nishii J, Morigaki K. Sensitive bioimaging in microfluidic channels on the plasmonic substrate: Application of an enhanced fluorescence based on the reverse coupling mode. J Photochem Photobiol A Chem 2011. [DOI: 10.1016/j.jphotochem.2011.04.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
10
|
Pokhriyal A, Lu M, Chaudhery V, Huang CS, Schulz S, Cunningham BT. Photonic crystal enhanced fluorescence using a quartz substrate to reduce limits of detection. OPTICS EXPRESS 2010; 18:24793-808. [PMID: 21164826 PMCID: PMC3408906 DOI: 10.1364/oe.18.024793] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
A Photonic Crystal (PC) surface fabricated upon a quartz substrate using nanoimprint lithography has been demonstrated to enhance light emission from fluorescent molecules in close proximity to the PC surface. Quartz was selected for its low autofluorescence characteristics compared to polymer-based PCs, improving the detection sensitivity and signal-to-noise ratio (SNR) of PC Enhanced Fluorescence (PCEF). Nanoimprint lithography enables economical fabrication of the subwavelength PCEF surface structure over entire 1x3 in2 quartz slides. The demonstrated PCEF surface supports a transverse magnetic (TM) resonant mode at a wavelength of λ = 632.8 nm and an incident angle of θ = 11°, which amplifies the electric field magnitude experienced by surface-bound fluorophores. Meanwhile, another TM mode at a wavelength of λ = 690 nm and incident angle of θ = 0° efficiently directs the fluorescent emission toward the detection optics. An enhancement factor as high as 7500 × was achieved for the detection of LD-700 dye spin-coated upon the PC, compared to detecting the same material on an unpatterned glass surface. The detection of spotted Alexa-647 labeled polypeptide on the PC exhibits a 330 × SNR improvement. Using dose-response characterization of deposited fluorophore-tagged protein spots, the PCEF surface demonstrated a 140 × lower limit of detection compared to a conventional glass substrate.
Collapse
Affiliation(s)
- Anusha Pokhriyal
- Dept. of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois,
USA
| | - Meng Lu
- SRU Biosystems, 14-A Gill St., Woburn, Massachusetts, 01810,
USA
| | - Vikram Chaudhery
- Dept. of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois,
USA
| | - Cheng-Sheng Huang
- Dept. of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois,
USA
| | - Stephen Schulz
- SRU Biosystems, 14-A Gill St., Woburn, Massachusetts, 01810,
USA
| | - Brian T. Cunningham
- Dept. of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois,
USA
- Dept. of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, Illinois,
USA
| |
Collapse
|
11
|
Aslan K, Previte MJR, Zhang Y, Geddes CD. Surface Plasmon Coupled Fluorescence in the Ultraviolet and Visible Spectral Regions Using Zinc Thin Films. Anal Chem 2008; 80:7304-12. [DOI: 10.1021/ac800923n] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Kadir Aslan
- Institute of Fluorescence, Laboratory for Advanced Medical Plasmonics and Laboratory for Advanced Fluorescence Spectroscopy, Medical Biotechnology Center, University of Maryland Biotechnology Institute, 725 West Lombard Street, Baltimore, Maryland 21201
| | - Michael J. R. Previte
- Institute of Fluorescence, Laboratory for Advanced Medical Plasmonics and Laboratory for Advanced Fluorescence Spectroscopy, Medical Biotechnology Center, University of Maryland Biotechnology Institute, 725 West Lombard Street, Baltimore, Maryland 21201
| | - Yongxia Zhang
- Institute of Fluorescence, Laboratory for Advanced Medical Plasmonics and Laboratory for Advanced Fluorescence Spectroscopy, Medical Biotechnology Center, University of Maryland Biotechnology Institute, 725 West Lombard Street, Baltimore, Maryland 21201
| | - Chris D. Geddes
- Institute of Fluorescence, Laboratory for Advanced Medical Plasmonics and Laboratory for Advanced Fluorescence Spectroscopy, Medical Biotechnology Center, University of Maryland Biotechnology Institute, 725 West Lombard Street, Baltimore, Maryland 21201
| |
Collapse
|
12
|
Henares TG, Mizutani F, Hisamoto H. Current development in microfluidic immunosensing chip. Anal Chim Acta 2008; 611:17-30. [DOI: 10.1016/j.aca.2008.01.064] [Citation(s) in RCA: 167] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2007] [Revised: 01/21/2008] [Accepted: 01/23/2008] [Indexed: 11/26/2022]
|
13
|
Matveeva EG, Gryczynski I, Barnett A, Calander N, Gryczynski Z. Red blood cells do not attenuate the SPCE fluorescence in surface assays. Anal Bioanal Chem 2007; 388:1127-35. [PMID: 17534609 DOI: 10.1007/s00216-007-1322-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2007] [Revised: 04/11/2007] [Accepted: 04/24/2007] [Indexed: 12/19/2022]
Abstract
We describe the positive effect of surface plasmon-coupled fluorescence emission (SPCE) on the detection of a signal from a surface immunoassay in highly absorbing or/and scattering samples. A model immunoassay using fluorescently labeled anti-rabbit antibodies that bind to rabbit immunoglobulin on a silver surface was performed, and the signal was detected in the presence of various highly absorbing and/or scattering solutions or suspensions, such as hemoglobin solution, plastic beads, and red blood cells. The results showed that a highly absorbing solution consisting of small molecules (dye, hemoglobin) attenuates the SPCE signal approximately 2-3-fold. In contrast, suspensions with the same absorption containing large particles (large beads, red blood cell suspension) attenuate the SPCE signal only slightly, approximately 5-10%. Also, a suspension of large undyed, highly scattering beads does not reduce the SPCE signal. The effects on the immunoassay signal of the sample background absorption and scattering, the size of the background particles, and the geometry of the experimental set-up are discussed. We believe that SPCE is a promising technique in the development of biosensors utilized for surface-based assays, as well as any assays performed directly in highly absorbing and/or scattering solutions without washing or separation procedures. Figure Red blood cells (unlike hemoglobin) do not attenuate the SPCE fluorescence in surface assays.
Collapse
Affiliation(s)
- Evgenia G Matveeva
- Department of Molecular Biology and Immunology, University of North Texas, Health Science Center, Fort Worth, TX 76107, USA.
| | | | | | | | | |
Collapse
|
14
|
Gryczynski I, Malicka J, Lukomska J, Gryczynski Z, R. Lakowicz J. Surface Plasmon-coupled Polarized Emission of N-Acetyl-l-Trytophanamide¶. Photochem Photobiol 2007. [DOI: 10.1111/j.1751-1097.2004.tb00118.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
15
|
Savchenko A, Kashuba E, Kashuba V, Snopok B. Imaging technique for the screening of protein-protein interactions using scattered light under surface plasmon resonance conditions. Anal Chem 2007; 79:1349-55. [PMID: 17297933 DOI: 10.1021/ac061456n] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We propose a novel technique to detect protein-protein interactions in microarray format. The technique involves measuring scattered light under surface plasmon resonance (SPR) conditions. We have shown that the maximum scattering angle correlates with the traditionally employed reflection minimum. Panoramic scanning of scattered light under SPR conditions has all the functional advantages of the SPR technique. In addition, the proposed technique simplifies device design, increases the dynamic range of analysis, and integrates data with those from surface-plasmon field-enhanced fluorescence spectroscopy. We demonstrate the technique by showing direct protein-protein interaction between protein A and either rabbit antibodies or human serum.
Collapse
Affiliation(s)
- Andrej Savchenko
- V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences, 41 Prospect Nauki, 03028 Kyiv, Ukraine
| | | | | | | |
Collapse
|
16
|
Gryczynski Z, Borejdo J, Calander N, Matveeva EG, Gryczynski I. Minimization of detection volume by surface-plasmon-coupled emission. Anal Biochem 2006; 356:125-31. [PMID: 16764813 DOI: 10.1016/j.ab.2006.05.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2006] [Revised: 05/03/2006] [Accepted: 05/05/2006] [Indexed: 10/24/2022]
Abstract
We report theoretical predictions and experimental observations of the reduced detection volume with the use of surface-plasmon-coupled emission (SPCE). The effective fluorescence volume (detection volume) in SPCE experiments depends on two near-field factors: the depth of evanescent wave excitation and a distance-dependent coupling of excited fluorophores to the surface plasmons. With direct excitation of the sample (reverse Kretschmann excitation) the detection volume is restricted only by the distance-dependent coupling of the excitation to the surface plasmons. However, with the excitation through the glass prism at surface plasmon resonance angle (Kretschmann configuration), the detection volume is a product of evanescent wave penetration depth and distance-dependent coupling. In addition, the detection volume is further reduced by a metal quenching of excited fluorophores at a close proximity (below 10nm). The height of the detected volume size is 40-70nm, depending on the orientation of the excited dipoles. We show that, by using the Kretschmann configuration in a microscope with a high-numerical-aperture objective (1.45) together with confocal detection, the detection volume can be reduced to 1-2attoL. The strong dependence of the coupling to the surface plasmons on the orientation of excited dipoles can be used to study the small conformational changes of macromolecules.
Collapse
Affiliation(s)
- Z Gryczynski
- Department of Molecular Biology and Immunology, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107, USA
| | | | | | | | | |
Collapse
|
17
|
Matveeva EG, Gryczynski I, Malicka J, Gryczynski Z, Goldys E, Howe J, Berndt KW, Lakowicz JR. Plastic versus glass support for an immunoassay on metal-coated surfaces in optically dense samples utilizing directional surface plasmon-coupled emission. J Fluoresc 2006; 15:865-71. [PMID: 16328701 PMCID: PMC6816260 DOI: 10.1007/s10895-005-0015-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
We compared plastic (polycarbonate) and high-quality glass support materials for gold-coated slides, when performing a model immunoassay against rabbit IgG using fluorescently labeled (AlexaFluor-647) anti-rabbit IgG, and detecting surface plasmon-coupled emission (SPCE) signals. Both, glass and plastic slides were simultaneously coated with a 48-nm layer of gold and protected with a 10-nm layer of silica. The maximum SPCE signal of AlexaFluor-647 was only two- to three-fold smaller on plastic slides than on glass slides. A small difference in the SPCE angles on glass (theta (F) = 55 degrees ) and plastic (theta (F) = 52.5 degrees ) slides was observed and can be explained with a slightly smaller refractive index of the plastic. We have not found any difference in the angle distribution (sharpness of the fluorescence signal at optimal SPCE angle) for the plastic slide compared to the glass slide. The kinetics of binding was monitored on the plastic slide as well as on the glass slide. Optically dense samples, a 4% red blood cell suspension and a 15% hemoglobin solution, are causing a reduction in the immunoassay SPCE signal by approximately 15% and three times, respectively, and the percentage of the reduction is the same for plastic and for glass slides. We believe that plastic substrates can be readily used in any SPCE assay, with only marginally lower total signal compared to high-quality glass slides.
Collapse
Affiliation(s)
- Evgenia G Matveeva
- Center for Fluorescence Spectroscopy, University of Maryland at Baltimore, School of Medicine, Department of Biochemistry and Molecular Biology, 725 West Lombard Street, Baltimore, Maryland 21201, USA.
| | | | | | | | | | | | | | | |
Collapse
|
18
|
Wang C, Li Y, Xiong J, Tan Y, Yu J. Using of the surface plasmon resonance cytosensor for real-time and non-invasive monitoring of cellular effects in living C6 cells induced by PMA. ACTA ACUST UNITED AC 2006. [DOI: 10.1007/s11434-006-0927-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
|
19
|
Kostov Y, Smith DS, Tolosa L, Rao G, Gryczynski I, Gryczynski Z, Malicka J, Lakowicz JR. Directional surface plasmon-coupled emission from a 3 nm green fluorescent protein monolayer. Biotechnol Prog 2006; 21:1731-5. [PMID: 16321058 PMCID: PMC6949142 DOI: 10.1021/bp050114k] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
High-sensitivity detection schemes are of great interest for a number of applications. Unfortunately, such schemes are usually high-cost. We demonstrate a low-cost approach to a high-sensitivity detection scheme based on surface plasmon-coupled emission (SPCE). The SPCE of a monomolecular layer of green fluorescent protein (GFP) is reported here. The protein was electrostatically attached to a thin, SiO(2)-protected silver film deposited on a quartz substrate. The visible, directional emission of GFP was observed at a sharp, well-defined angle of 47.5 degrees from the normal to the coupling prism, and the spectrum corresponded to that of GFP. The SPCE resulting from the reverse Kretschmann configuration showed a 12-fold enhancement over the free space fluorescence. The directional emission was 97% p-polarized. The directionality and high polarization can be coupled with the intrinsic spectral resolution of SPCE to be used in the design miniaturized spectrofluorometers. The observation of SPCE in the visible region of the spectrum from a monolayer of protein opens up new possibilities in protein-based sensing.
Collapse
Affiliation(s)
| | | | | | - Govind Rao
- To whom correspondence should be addressed. (G.R.) Fax: 410-455-6500. . (Z.G.) Fax: 410-706-8408.
| | | | - Zygmunt Gryczynski
- To whom correspondence should be addressed. (G.R.) Fax: 410-455-6500. . (Z.G.) Fax: 410-706-8408.
| | | | | |
Collapse
|
20
|
Matveeva EG, Gryczynski Z, Malicka J, Lukomska J, Makowiec S, Berndt KW, Lakowicz JR, Gryczynski I. Directional surface plasmon-coupled emission: application for an immunoassay in whole blood. Anal Biochem 2006; 344:161-7. [PMID: 16091280 PMCID: PMC6816263 DOI: 10.1016/j.ab.2005.07.005] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2004] [Revised: 07/01/2005] [Accepted: 07/06/2005] [Indexed: 12/31/2022]
Abstract
We present a new approach for performing fluorescence immunoassay in whole blood using fluorescently labeled anti-rabbit immunoglobulin G (IgG) on a silver surface. This approach, which is based on surface plasmon-coupled emission (SPCE), provides increased sensitivity and substantial background reduction due to exclusive selection of the signal from the fluorophores located near a bioaffinity surface. This article describes the effect of an optically dense sample matrix, namely human whole blood and serum, on the intensity of the SPCE. An antigen (rabbit IgG) was adsorbed to a slide covered with a thin silver metal layer, and the SPCE signal from the fluorophore-labeled anti-rabbit antibody, binding to the immobilized antigen, was detected. The effect of the sample matrix (buffer, human serum, or human whole blood) on the end-point immunoassay SPCE signal was studied. It was demonstrated that the kinetics of binding could be monitored directly in whole blood or serum. The results showed that human serum and human whole blood attenuate the SPCE end-point signal and the immunoassay kinetic signal only approximately two- and threefold, respectively, as compared with buffer, resulting in signals that are easily detectable even in whole blood. The high optical absorption of the hemoglobin can be tolerated because only fluorophores within a couple of hundred nanometers from the metallic film contribute to SPCE. Excited fluorophores outside the 200-nm layer do not contribute to SPCE, and their free space emission is not transmitted through the opaque metallic film into the glass substrate. We believe that SPCE has the potential of becoming a powerful approach for performing immunoassays based on surface-bound analytes or antibodies for many biomarkers directly in dense samples such as whole blood with no need for washing steps.
Collapse
Affiliation(s)
- Evgenia G Matveeva
- Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, School of Medicine, University of Maryland at Baltimore, Baltimore, MD 21201, USA.
| | | | | | | | | | | | | | | |
Collapse
|
21
|
Smith DS, Kostov Y, Rao G, Gryczynski I, Malicka J, Gryczynski Z, Lakowicz JR. First observation of surface plasmon-coupled emission due to LED excitation. J Fluoresc 2005; 15:895-900. [PMID: 16328699 PMCID: PMC6830068 DOI: 10.1007/s10895-005-0021-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2005] [Accepted: 09/29/2005] [Indexed: 10/25/2022]
Abstract
Detection limitations for fluorescence methods are normally determined by the phenomenon itself rather than the sensitivity of the instrumentation. These limitations make it necessary to have high sensitivity, high cost equipment causing fluorescence methods to remain lab-oriented. Alleviation of the limitations can be achieved through the phenomenon of surface plasmon-coupled emission (SPCE), which displays enhanced, directional, polarized fluorescence. Here we present the excitation of SPCE from Rhodamine B with a light-emitting diode (LED). Incorporating the gains in sensitivity due to SPCE with LED excitation, it could be possible to design low-cost, high-sensitivity sensors that would allow measurements to be performed in the field.
Collapse
Affiliation(s)
- Derek S. Smith
- Department of Chemical and Biochemical Engineering, Center for Advanced Sensor Technology, University of Maryland at Baltimore County, 5200 Westland Blvd, Baltimore, Maryland 21227
| | - Yordan Kostov
- Department of Chemical and Biochemical Engineering, Center for Advanced Sensor Technology, University of Maryland at Baltimore County, 5200 Westland Blvd, Baltimore, Maryland 21227
| | - Govind Rao
- Department of Chemical and Biochemical Engineering, Center for Advanced Sensor Technology, University of Maryland at Baltimore County, 5200 Westland Blvd, Baltimore, Maryland 21227
- To whom correspondence should be addressed.
| | - Ignacy Gryczynski
- Department of Biochemistry and Molecular Biology, Center for Fluorescence Spectroscopy, University of Maryland at Baltimore, 725 West Lombard Street, Baltimore, Maryland 21201
| | - Joanna Malicka
- Department of Biochemistry and Molecular Biology, Center for Fluorescence Spectroscopy, University of Maryland at Baltimore, 725 West Lombard Street, Baltimore, Maryland 21201
| | - Zygmunt Gryczynski
- Department of Biochemistry and Molecular Biology, Center for Fluorescence Spectroscopy, University of Maryland at Baltimore, 725 West Lombard Street, Baltimore, Maryland 21201
| | - Joseph R. Lakowicz
- Department of Biochemistry and Molecular Biology, Center for Fluorescence Spectroscopy, University of Maryland at Baltimore, 725 West Lombard Street, Baltimore, Maryland 21201
| |
Collapse
|
22
|
Gryczynski I, Malicka J, Lakowicz JR, Goldys EM, Calander N, Gryczynski Z. Directional two-photon induced surface plasmon-coupled emission. THIN SOLID FILMS 2005; 491:173-176. [PMID: 33828343 PMCID: PMC8022891 DOI: 10.1016/j.tsf.2005.06.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
We measured a directional surface plasmon-coupled emission (SPCE) induced by a two-photon absorption. A 60 nm thick layer of poly(vinyl alcohol) film doped with rhodamine 123 was deposited on a silvered (50 nm Ag) glass slide, which was attached to a hemicylindrical glass prism. The 820 nm excitation from a femtosecond Ti:Sapphire laser was used either in reverse Kretschmann or Kretschmann configuration. The angular distribution of two-photon induced SPCE does not depend on the used configuration. The two-photon induced SPCE can be applied to improve immunoassays and deoxyribonucleic acid detection.
Collapse
Affiliation(s)
- Ignacy Gryczynski
- Center for Fluorescence Spectroscopy, University of Maryland at Baltimore, Department of Biochemistry and Molecular Biology, 725 West Lombard Street, Baltimore, MD 21201, USA
| | - Joanna Malicka
- Center for Fluorescence Spectroscopy, University of Maryland at Baltimore, Department of Biochemistry and Molecular Biology, 725 West Lombard Street, Baltimore, MD 21201, USA
| | - Joseph R. Lakowicz
- Center for Fluorescence Spectroscopy, University of Maryland at Baltimore, Department of Biochemistry and Molecular Biology, 725 West Lombard Street, Baltimore, MD 21201, USA
| | - Ewa M. Goldys
- Optical Microcharacterisation Facility, Division of Information and Communication Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Nils Calander
- Department of Physics, Chalmers University of Technology, Göteborg University, S-412 96 Göteborg, Sweden
| | - Zygmunt Gryczynski
- Center for Fluorescence Spectroscopy, University of Maryland at Baltimore, Department of Biochemistry and Molecular Biology, 725 West Lombard Street, Baltimore, MD 21201, USA
| |
Collapse
|
23
|
Mattheyses AL, Axelrod D. Fluorescence emission patterns near glass and metal-coated surfaces investigated with back focal plane imaging. JOURNAL OF BIOMEDICAL OPTICS 2005; 10:054007. [PMID: 16292967 DOI: 10.1117/1.2052867] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Often fluorophores observed by microscopy are located close to a planar surface as in total internal reflection microscopy or single molecule studies. The optical properties of fluorescence excitation and emission near a planar surface (possibly metal film coated) between two dielectrics are well understood from the viewpoint of classical electromagnetic theory. We present an experimental method whereby the angular dependence of the emission pattern of a fluorophore near a bare surface or a metal film coated surface that supports surface plasmon resonance can be measured with microscope optics. The technique involves an alteration of the microscope optics to directly record (on a digital CCD camera) the intensity pattern at the objective's back focal plane, which directly maps the angular emission pattern of fluorescence. The experimental emission profile on both glass and aluminum-coated surfaces is anisotropic with a peak at either the critical angle or both the critical angle and the surface plasmon angle. The observed profiles agree well with computer calculations and suggest some optical modifications that are potentially useful in cell biophysics.
Collapse
Affiliation(s)
- Alexa L Mattheyses
- University of Michigan, Biophysics Research Division, Ann Arbor, Michigan 48109, USA.
| | | |
Collapse
|
24
|
Lakowicz JR, Malicka J, Matveeva E, Gryczynski I, Gryczynski Z. Plasmonic technology: novel approach to ultrasensitive immunoassays. Clin Chem 2005; 51:1914-22. [PMID: 16055432 PMCID: PMC2763913 DOI: 10.1373/clinchem.2005.053199] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
At the Center for Fluorescence Spectroscopy, we have taken advantage of the favorable properties of surface plasmon-coupled emission (SPCE) to improve fluorescence-based immunoassays. SPCE occurs when excited fluorophores near conducting metallic structures efficiently couple to surface plasmons. These surface plasmons, appearing as free electron oscillations in the metallic layer, produce electromagnetic radiation that preserves the spectral properties of fluorophores but is highly polarized and directional. SPCE immunoassays provide several advantages over other fluorescence-based methods. This review explains new approaches to fluorescence immunoassays, including our own use of SPCE for simultaneous detection of more than one fluorescent marker and performance of immunoassays in the presence of an optically dense medium, such as whole blood.
Collapse
Affiliation(s)
- Joseph R Lakowicz
- Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
| | | | | | | | | |
Collapse
|
25
|
Calander N. Surface Plasmon-Coupled Emission and Fabry−Perot Resonance in the Sample Layer: A Theoretical Approach. J Phys Chem B 2005; 109:13957-63. [PMID: 16852751 DOI: 10.1021/jp0510544] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A theoretical approach is used to investigate the coupling of surface plasmon-coupled emission to Fabry-Perot resonance in the sample layer. Quantities investigated are emission angles, polarization, power levels, and fluorescence lifetimes. The results are compared to experimental findings. For comparison a layered structure without surface plasmons, possessing only dielectric Fabry-Perot resonances, is explored. This structure seems to be amenable to s-polarization only but is in principle loss-less and has more degrees of freedom for design and optimization.
Collapse
Affiliation(s)
- Nils Calander
- Department of Physics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden.
| |
Collapse
|
26
|
Gryczynski I, Malicka J, Lukomska J, Gryczynski Z, Lakowicz JR. Surface plasmon-coupled polarized emission of N-acetyl-l-tryptophanamide. Photochem Photobiol 2004. [PMID: 15623334 DOI: 10.1562/0031-8655(2004)080<0482:sppeon>2.0.co;2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
Abstract
We report an observation of ultraviolet (UV) surface plasmon-coupled emission (SPCE) of N-acetyl-l-tryptophanamide (NATA). The sample was spin coated from poly(vinyl alcohol) (PVA) solution on 20 nm aluminum film deposited on a quartz substrate. The directional UV SPCE occurs within a well-defined narrow angle at 52 degrees from the normal to the coupling hemicylinder quartz prism. The NATA directional emission is highly p polarized as expected for surface plasmon-coupled radiation. The 10 nm protective SiO2 layer deposited on top of the aluminum film significantly neutralized the fluorophore quenching by the metal surface. SPCE of NATA demonstrates a remarkable intrinsic dispersive property-the maximum of the emission spectrum depends on the observation angle. The efficient spectral resolution of SPCE can be used in the construction of miniaturized spectrofluorometers. The observation of SPCE of tryptophan opens a new possibility for the study of many unlabeled proteins with the technique complementary to surface plasmon resonance analysis.
Collapse
Affiliation(s)
- Ignacy Gryczynski
- Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, University of Maryland at Baltimore, Baltimore, MD 21201, USA
| | | | | | | | | |
Collapse
|
27
|
Matveeva E, Gryczynski Z, Gryczynski I, Malicka J, Lakowicz JR. Myoglobin immunoassay utilizing directional surface plasmon-coupled emission. Anal Chem 2004; 76:6287-92. [PMID: 15516120 PMCID: PMC6848856 DOI: 10.1021/ac0491612] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We described an immunoassay for the cardiac marker myoglobin on a thin silver mirror surface using surface plasmon-coupled emission (SPCE). SPCE occurs for fluorophores in proximity (within approximately 200 nm) of a thin metal film (in our case, silver) and results in a highly directional radiation through a glass substrate at a well-defined angle from the normal axis. We used the effect of SPCE to develop a myoglobin immunoassay on the silver mirror surface deposited on a glass substrate. Binding of the labeled anti-myoglobin antibodies led to the enhanced fluorescence emission at a specific angle of 72 degrees . The directional and enhanced directional fluorescence emission enables detection of myoglobin over a wide range of concentrations from subnormal to the elevated level of this cardiac marker. Utilizing SPCE allowed us also to demonstrate significant background suppression (from serum or whole blood) in the myoglobin immunoassay. We expect SPCE to become a powerful technique for performing immunoassays for many biomarkers in surface-bound assays.
Collapse
Affiliation(s)
- Evgenia Matveeva
- Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, University of Maryland at Baltimore, 725 West Lombard Street, Baltimore, Maryland 21201
| | - Zygmunt Gryczynski
- Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, University of Maryland at Baltimore, 725 West Lombard Street, Baltimore, Maryland 21201
| | - Ignacy Gryczynski
- Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, University of Maryland at Baltimore, 725 West Lombard Street, Baltimore, Maryland 21201
| | - Joanna Malicka
- Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, University of Maryland at Baltimore, 725 West Lombard Street, Baltimore, Maryland 21201
| | - Joseph R. Lakowicz
- Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, University of Maryland at Baltimore, 725 West Lombard Street, Baltimore, Maryland 21201
| |
Collapse
|
28
|
Gryczynski I, Malicka J, Lukomska J, Gryczynski Z, Lakowicz JR. Surface Plasmon–coupled Polarized Emission of N-Acetyl-l-Tryptophanamide¶. Photochem Photobiol 2004; 80:482-5. [PMID: 15623334 PMCID: PMC6848917 DOI: 10.1562/0031-8655(2004)080<0482:sppeon>2.0.co;2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We report an observation of ultraviolet (UV) surface plasmon-coupled emission (SPCE) of N-acetyl-l-tryptophanamide (NATA). The sample was spin coated from poly(vinyl alcohol) (PVA) solution on 20 nm aluminum film deposited on a quartz substrate. The directional UV SPCE occurs within a well-defined narrow angle at 52 degrees from the normal to the coupling hemicylinder quartz prism. The NATA directional emission is highly p polarized as expected for surface plasmon-coupled radiation. The 10 nm protective SiO2 layer deposited on top of the aluminum film significantly neutralized the fluorophore quenching by the metal surface. SPCE of NATA demonstrates a remarkable intrinsic dispersive property-the maximum of the emission spectrum depends on the observation angle. The efficient spectral resolution of SPCE can be used in the construction of miniaturized spectrofluorometers. The observation of SPCE of tryptophan opens a new possibility for the study of many unlabeled proteins with the technique complementary to surface plasmon resonance analysis.
Collapse
Affiliation(s)
| | - Joanna Malicka
- To whom correspondence should be addressed: Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, University of Maryland at Baltimore, 725 West Lombard Street, Baltimore, MD 21201, USA. Fax: 410-706-8408;
| | | | | | | |
Collapse
|
29
|
Gryczynski Z, Gryczynski I, Matveeva E, Malicka J, Nowaczyk K, Lakowicz JR. Surface-Plasmon–Coupled Emission: New Technology for Studying Molecular Processes. Methods Cell Biol 2004; 75:73-104. [PMID: 15603423 DOI: 10.1016/s0091-679x(04)75004-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Zygmunt Gryczynski
- Center for Fluorescence Spectroscopy, University of Maryland at Baltimore, Department of Biochemistry and Molecular Biology, Baltimore, Maryland 21201, USA
| | | | | | | | | | | |
Collapse
|