Abstract

We investigate the target dependence of the sensitivity in a localized surface plasmon resonance (LSPR) biosensor and compare it with that of a conventional thin-film-based plasmon resonance structure. An LSPR biosensor was modeled as subwavelength periodic nanowires on a metal/dielectric substrate and targets either as bulk refractive index changes or as a biomolecular interaction that forms a monolayer. The results found that significant target-dependent variation arises in sensitivity and sensitivity enhancement by LSPR. The variation is attributed to the nonlinearity in the plasmon dispersion relation as well as the effective permittivity due to strong LSPR signals. The target dependence suggests that an LSPR structure be designed based on estimated index changes induced by target interactions. Associated broadening of resonance width can be controlled by way of profile engineering, which is discussed in connection with experimental data.

© 2008 Optical Society of America

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References

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    [CrossRef] [PubMed]
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    [CrossRef] [PubMed]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
  38. J. Kottmann, O. Martin, D. Smith, and S. Schultz, “Spectral response of plasmon resonant nanoparticles with a non-regular shape,” Opt. Express 6, 213-219 (2000).
    [CrossRef] [PubMed]
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    [CrossRef]

2007 (6)

2006 (4)

2005 (4)

2004 (4)

A. J. Haes and R. P. Van Duyne, “A unified view of propagating and localized surface plasmon resonance biosensors,” Anal. Bioanal. Chem. 379, 920-930 (2004).
[CrossRef] [PubMed]

F.-C. Chien and S. J. Chen, “A sensitivity comparison of optical biosensors based on four different surface plasmon resonance modes,” Biosens. Bioelectron. 20, 633-642 (2004).
[CrossRef] [PubMed]

T. Vallius, J. Turunen, M. Mansuripur, and S. Honkanen, “Transmission through single subwavelength apertures in thin metal films and effects of surface plasmons,” J. Opt. Soc. Am. A 21, 456-463 (2004).
[CrossRef]

S. Y. Wu, H. P. Ho, W. C. Law, C. Lin, and S. K. Kong, “Highly sensitive differential phase-sensitive surface plasmon resonance biosensor based on the Mach-Zehnder configuration,” Opt. Lett. 29, 2378-2380 (2004).
[CrossRef] [PubMed]

2003 (2)

E. A. Smith, W. D. Thomas, L. L. Kiessling, and R. M. Corn, “Surface plasmon resonance imaging studies of protein-carbohydrate interactions,” J. Am. Chem. Soc. 125, 6140-6148 (2003).
[CrossRef] [PubMed]

A. J. A. El-Haija, “Effective medium approximation for the effective optical constants of a bilayer and a multilayer structure based on the characteristic matrix technique,” J. Appl. Phys. 93, 2590-2594 (2003).
[CrossRef]

2001 (5)

J. P. Kottman, O. J. F. Martin, D. R. Smith, and S. Schultz, “Plasmon resonances of silver nanowires with a nonregular cross section,” Phys. Rev. B 64, 235402 (2001).
[CrossRef]

J. P. Kottmann and O. J. F. Martin, “Influence of the cross section and the permittivity on the plasmon resonances spectrum of silver nanowires,” Appl. Phys. B 73, 299-304 (2001).
[CrossRef]

Y. Kanamori, K. Hane, H. Sai, and H. Yugami, “100 nm period silicon antireflection structures fabricated using a porous alumina membrane mask,” Appl. Phys. (N.Y.) 78, 142-143 (2001).

M. D. Malinsky, K. L. Kelly, G. C. Schatz, and R. P. Van Duyne, “Chain length dependence and sensing capabilities of the localized surface plasmon resonance of silver nanoparticles chemically modified with alkanethiol self-assembled monolayers,” J. Am. Chem. Soc. 123, 1471-1482 (2001).
[CrossRef]

E. Hutter, S. Cha, J.-F. Liu, J. Park, J. Yi, J. H. Fendler, and D. Roy, “Role of substrate metal in gold nanoparticle enhanced surface plasmon resonance imaging,” J. Phys. Chem. B 105, 8-12 (2001).
[CrossRef]

2000 (3)

T. M. Davis and W. D. Wilson, “Determination of the refractive index increments of small molecules for correction of surface plasmon resonance data,” Anal. Biochem. 284, 348-353 (2000).
[CrossRef] [PubMed]

L. He, M. D. Musick, S. R. Nicewarner, F. G. Salinas, S. J. Benkovic, M. J. Natan, and C. D. Keating, “Colloidal Au-enhanced surface plasmon resonance for ultrasensitive detection of DNA hybridization,” J. Am. Chem. Soc. 122, 9071-9077 (2000).
[CrossRef]

J. Kottmann, O. Martin, D. Smith, and S. Schultz, “Spectral response of plasmon resonant nanoparticles with a non-regular shape,” Opt. Express 6, 213-219 (2000).
[CrossRef] [PubMed]

1999 (1)

J. Homola, I. Koudela, and S. S. Yee, “Surface plasmon resonance sensors based on diffraction gratings and prism couplers: sensitivity comparison,” Sens. Actuators B 54, 16-24 (1999).
[CrossRef]

1998 (1)

L. A. Lyon, M. D. Musick, and M. J. Natan, “Colloidal Au-enhanced surface plasmon resonance immunosensing,” Anal. Chem. 70, 5177-5183 (1998).
[CrossRef] [PubMed]

1995 (1)

B. Liedberg, C. Nylander, and I. Lundstrom, “Biosensing with surface plasmon resonance--how it all started,” Biosens. Bioelectron. 10, R1-R9 (1995).
[CrossRef]

1986 (1)

1976 (1)

I. Pockrand and H. Raether, “Surface plasma oscillations in silver films with navy surface profiles: a quantitative experimental study,” Opt. Commun. 18, 395-399 (1976).
[CrossRef]

1972 (1)

E. Kretschmann, “Decay of nonradiative surface plasmons into light on rough silver films. Comparison of experimental and theoretical results,” Opt. Commun. 6, 185-187 (1972).
[CrossRef]

1956 (1)

S. M. Rytov, “Electromagnetic properties of a finely stratified medium,” Sov. Phys. JETP 2, 466-475 (1956).

1946 (1)

T. A. Scott, “Refractive-index of ethanol-water mixtures and density and refractive index of ethanol-water-ethyl ether mixtures,” J. Phys. Chem. 50, 406-412 (1946).
[CrossRef] [PubMed]

Anal. Bioanal. Chem. (1)

A. J. Haes and R. P. Van Duyne, “A unified view of propagating and localized surface plasmon resonance biosensors,” Anal. Bioanal. Chem. 379, 920-930 (2004).
[CrossRef] [PubMed]

Anal. Biochem. (1)

T. M. Davis and W. D. Wilson, “Determination of the refractive index increments of small molecules for correction of surface plasmon resonance data,” Anal. Biochem. 284, 348-353 (2000).
[CrossRef] [PubMed]

Anal. Chem. (1)

L. A. Lyon, M. D. Musick, and M. J. Natan, “Colloidal Au-enhanced surface plasmon resonance immunosensing,” Anal. Chem. 70, 5177-5183 (1998).
[CrossRef] [PubMed]

Appl. Opt. (1)

Appl. Phys. (N.Y.) (1)

Y. Kanamori, K. Hane, H. Sai, and H. Yugami, “100 nm period silicon antireflection structures fabricated using a porous alumina membrane mask,” Appl. Phys. (N.Y.) 78, 142-143 (2001).

Appl. Phys. B (1)

J. P. Kottmann and O. J. F. Martin, “Influence of the cross section and the permittivity on the plasmon resonances spectrum of silver nanowires,” Appl. Phys. B 73, 299-304 (2001).
[CrossRef]

Biosens. Bioelectron. (3)

F.-C. Chien and S. J. Chen, “A sensitivity comparison of optical biosensors based on four different surface plasmon resonance modes,” Biosens. Bioelectron. 20, 633-642 (2004).
[CrossRef] [PubMed]

F.-C. Chien, C.-Y. Lin, J.-N. Yih, K.-L. Lee, C.-W. Chang, P.-K. Wei, C.-C. Sun, and S.-J. Chen “Coupled waveguide-surface plasmon resonance biosensor with subwavelength grating,” Biosens. Bioelectron. 22, 2737-2742 (2007).
[CrossRef]

B. Liedberg, C. Nylander, and I. Lundstrom, “Biosensing with surface plasmon resonance--how it all started,” Biosens. Bioelectron. 10, R1-R9 (1995).
[CrossRef]

J. Am. Chem. Soc. (3)

L. He, M. D. Musick, S. R. Nicewarner, F. G. Salinas, S. J. Benkovic, M. J. Natan, and C. D. Keating, “Colloidal Au-enhanced surface plasmon resonance for ultrasensitive detection of DNA hybridization,” J. Am. Chem. Soc. 122, 9071-9077 (2000).
[CrossRef]

M. D. Malinsky, K. L. Kelly, G. C. Schatz, and R. P. Van Duyne, “Chain length dependence and sensing capabilities of the localized surface plasmon resonance of silver nanoparticles chemically modified with alkanethiol self-assembled monolayers,” J. Am. Chem. Soc. 123, 1471-1482 (2001).
[CrossRef]

E. A. Smith, W. D. Thomas, L. L. Kiessling, and R. M. Corn, “Surface plasmon resonance imaging studies of protein-carbohydrate interactions,” J. Am. Chem. Soc. 125, 6140-6148 (2003).
[CrossRef] [PubMed]

J. Appl. Phys. (1)

A. J. A. El-Haija, “Effective medium approximation for the effective optical constants of a bilayer and a multilayer structure based on the characteristic matrix technique,” J. Appl. Phys. 93, 2590-2594 (2003).
[CrossRef]

J. Opt. Soc. Am. A (4)

J. Phys. Chem. (1)

T. A. Scott, “Refractive-index of ethanol-water mixtures and density and refractive index of ethanol-water-ethyl ether mixtures,” J. Phys. Chem. 50, 406-412 (1946).
[CrossRef] [PubMed]

J. Phys. Chem. B (1)

E. Hutter, S. Cha, J.-F. Liu, J. Park, J. Yi, J. H. Fendler, and D. Roy, “Role of substrate metal in gold nanoparticle enhanced surface plasmon resonance imaging,” J. Phys. Chem. B 105, 8-12 (2001).
[CrossRef]

Opt. Commun. (2)

E. Kretschmann, “Decay of nonradiative surface plasmons into light on rough silver films. Comparison of experimental and theoretical results,” Opt. Commun. 6, 185-187 (1972).
[CrossRef]

I. Pockrand and H. Raether, “Surface plasma oscillations in silver films with navy surface profiles: a quantitative experimental study,” Opt. Commun. 18, 395-399 (1976).
[CrossRef]

Opt. Express (8)

P. P. Markowicz, W. C. Law, A. Baev, P. N. Prasad, S. Patskovsky, and A. Kabashin, “Phase-sensitive time-modulated surface plasmon resonance polarimetry for wide dynamic range biosensing,” Opt. Express 15, 1745-1754 (2007).
[CrossRef] [PubMed]

W.-C. Liu, “High sensitivity of surface plasmon of weakly-distorted metallic surfaces,” Opt. Express 13, 9766-9773 (2005).
[CrossRef] [PubMed]

J. Kottmann, O. Martin, D. Smith, and S. Schultz, “Spectral response of plasmon resonant nanoparticles with a non-regular shape,” Opt. Express 6, 213-219 (2000).
[CrossRef] [PubMed]

B. Ran and S. G. Lipson, “Comparison between sensitivities of phase and intensity detection in surface plasmon resonance,” Opt. Express 14, 5641-5650 (2006).
[CrossRef] [PubMed]

D. Crouse and P. Keshavareddy, “Role of optical and surface plasmon modes in enhanced transmission and applications,” Opt. Express 13, 7760-7771 (2005).
[CrossRef] [PubMed]

K. M. Byun, S. J. Kim, and D. Kim, “Design study of highly sensitive nanowire-enhanced surface plasmon resonance biosensors using rigorous coupled wave analysis,” Opt. Express 13, 3737-3742 (2005).
[CrossRef] [PubMed]

K. Kim, S. J. Yoon, and D. Kim, “Nanowire-based enhancement of localized surface plasmon resonance for highly sensitive detection: a theoretical study,” Opt. Express 14, 12419-12431 (2006).
[CrossRef] [PubMed]

C. J. Alleyne, A. G. Kirk, R. C. McPhedran, N.-A. P. Nicorovici, and D. Maystre, “Enhanced SPR sensitivity using periodic metallic structures,” Opt. Express 15, 8163-8169 (2007).
[CrossRef] [PubMed]

Opt. Lett. (4)

Phys. Rev. B (1)

J. P. Kottman, O. J. F. Martin, D. R. Smith, and S. Schultz, “Plasmon resonances of silver nanowires with a nonregular cross section,” Phys. Rev. B 64, 235402 (2001).
[CrossRef]

Sens. Actuators B (1)

J. Homola, I. Koudela, and S. S. Yee, “Surface plasmon resonance sensors based on diffraction gratings and prism couplers: sensitivity comparison,” Sens. Actuators B 54, 16-24 (1999).
[CrossRef]

Sov. Phys. JETP (1)

S. M. Rytov, “Electromagnetic properties of a finely stratified medium,” Sov. Phys. JETP 2, 466-475 (1956).

Other (3)

M. Born and E. Wolf, Principles of Optics (Cambridge U. Press, 1999), pp. 837-840.

H. Raether, Surface Plasmon on Smooth and Rough Surfaces and on Gratings (Springer-Verlag, 1988) Chap. 2.

E. Palik, Handbook of Optical Constants of Solids (Academic Press, 1985).

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Figures (9)

Fig. 1
Fig. 1

(a) Schematics of a conventional thin-film-based SPR structure. (b) Target sensing of a bulk refractive index change and (c) a target binding model in a SAM using an LSPR structure based on periodic nanowires.

Fig. 2
Fig. 2

Resonance angles with a bulk refractive index of an environment n env on (a) BK7, (b) SF10, and (c) LaSFN31 substrates.

Fig. 3
Fig. 3

SEF with respect to bulk refractive index ( n env ) calculated analytically by Eq. (7) and also by RCWA in the case of target sensing of a bulk refractive index change. The inset shows the effective refractive index of a combined layer of nanowires and an environment.

Fig. 4
Fig. 4

Resonance angles with a refractive index of a target binding layer ( n SAM ) on (a) BK7, (b) SF10, and (c) LaSFN31 substrates, when a target interaction forms a SAM in a water environment.

Fig. 5
Fig. 5

SEF with respect to analyte refractive index ( n SAM ) calculated numerically by RCWA in the case of detecting a target binding interaction that forms a SAM ( d SAM = 3 nm ) in water.

Fig. 6
Fig. 6

Resonance characteristics of a conventional thin-film-based SPR and a nanowire-based LSPR structure with Λ = 50 and 100 nm . A 3 - nm -thick HDT-SAM is assumed on a LaSFN31 substrate in water.

Fig. 7
Fig. 7

Schematics of a nanowire-based LSPR structure that is engineered to control the width of resonance characteristics while providing high sensitivity enhancement. Not shown in the schematic is w bottom , which is the width of the nanowire bottom.

Fig. 8
Fig. 8

Resonance characteristics of LSPR excited by periodic nanowires of a T-profile compared with a rectangular profile and conventional SPR for a HDT-SAM at d SAM = 1 nm for Λ = 100 nm and f = 50 % . Water environment is assumed. Insets are 2-D near-field distribution of electric and magnetic field amplitudes ( E x , H y , and E z ) of T-shaped nanowires at resonance and off resonance in A and B, compared with rectangular nanowires in C and D, calculated by finite-difference time domain method. For both structures, d f = 40 nm and d NW = 20 nm .

Fig. 9
Fig. 9

Resonance characteristics of a conventional SPR (solid square) and a profile-engineered (open square, inverse trapezoidal) nanowire-based LSPR structure with Λ = 200 nm . Solid curves represent theoretical results.

Tables (2)

Tables Icon

Table 1 Sensitivity and SEF Calculated for a BK7, SF10, and LaSFN31 Substrate in a Water Environment

Tables Icon

Table 2 Performance of LSPR Sensor Structures of a T-Shaped Profile and a Rectangular Profile a

Equations (21)

Equations on this page are rendered with MathJax. Learn more.

SEF = δ θ nwsp δ θ sp = θ nwsp ( target analyte ) θ nwsp ( no analyte ) θ sp ( target analyte ) θ sp ( no analyte ) ,
K SP ( m ) = w c ( ε 1 ε 2 , eff ε 1 + ε 2 , eff ) 1 2 = K 0 sin θ sp m K G .
( ε 1 ε 2 , eff ε 1 + ε 2 , eff ) 1 2 = n s sin θ sp .
Re ( K SP ( 0 ) ) w c ( ε 1 ε 2 , eff ε 1 + ε 2 , eff ) 1 2 ,
Im ( K SP ( 0 ) ) w c ( ε 1 ε 2 , eff ε 1 + ε 2 , eff ) 3 2 ε 1 2 ( ε 1 ) 2 ,
S = 1 2 ( ε 1 3 ( ε 1 + ε 2 , eff ) 3 ε 2 , eff ) 1 2 1 n s cos θ nw sp ε 2 , eff n = ε 1 ε 1 ( ε 1 + ε 2 , eff ) ε 1 ε 2 , eff n s 2 ( ε 1 + ε 2 , eff ) 1 2 ε 2 , eff ε 2 , eff n .
SEF = ( ( ε 1 + ε 2 , eff , no wire ) 3 ε 2 , eff , no wire ( ε 1 + ε 2 , eff ) 3 ε 2 , eff ) 1 2 cos θ sp cos θ nw sp ε 2 , eff n ε 2 , eff , no wire n = ( ε 1 + ε 2 , eff , no wire ) ε 1 ε 2 , eff , no wire n s 2 ( ε 1 + ε 2 , eff , no wire ) ( ε 1 + ε 2 , eff ) ε 1 ε 2 , eff n s 2 ( ε 1 + ε 2 , eff ) ε 2 , eff , no wire ε 2 , eff ε 2 , eff n ε 2 , eff , no wire n .
S = ε 1 2 ε 2 , eff λ 2 ε 1 ε 2 , eff n s ( ε 1 + ε 2 , eff ) n s λ ( ε 1 2 ε 2 , eff λ + ε 2 , eff 2 ε 1 λ ) .
ε 2 , eff , no wire = n env 2 ,
d PD = λ 4 π n s 2 sin 2 θ ε env .
ε 2 , eff ( 2 , TM ) = ε 2 , eff ( 0 , TM ) + π 2 3 f 2 ( 1 f ) 2 ( 1 ε 1 1 ε env ) 2 ( ε 2 , eff ( 0 , TM ) ) 3 ε 2 , eff ( 0 , TE ) ( Λ λ ) 2 ,
ε 2 , eff ( 0 , TE ) = f ε 1 + ( 1 f ) ε env ,
1 ε 2 , eff ( 0 , TM ) = f ε 1 + ( 1 f ) ε env .
1 ε 2 , eff = 1 ε 2 , eff ( 2 , TM ) [ 1 exp ( d NW d PD ) ] + 1 ε env exp ( d NW d PD ) .
d PD = α λ 4 π n s 2 sin 2 θ ε env .
1 ε 2 , eff = β ε 2 , eff ( 2 , TM ) [ 1 exp ( d NW d PD ) ] + γ ε env exp ( d NW d PD ) .
1 ε 2 , eff = β ε 2 , eff ( 2 , TM ) { 1 exp [ 4 π d NW α λ ( ε 1 ε 2 , eff ε 1 + ε 2 , eff ) ε env ] } + γ ε env exp [ 4 π d NW α λ ( ε 1 ε 2 , eff ε 1 + ε 2 , eff ) ε env ] .
ε 2 , eff n env = 2 n env ( ε 2 , eff ) 2 β 1 e d NW d PD ( ε 2 , eff ( 2 , TM ) ) 2 ε 2 , eff ( 2 , TM ) ε env + γ e d NW d PD ε env 2 8 π 2 d NW d PD α 2 λ 2 ( γ ε env β ε 2 , eff ( 2 , TM ) ) e d NW d PD 1 8 π 2 d NW d PD α 2 λ 2 ( γ ε env β ε 2 , eff ( 2 , TM ) ) e d NW d PD ε 1 2 ε 2 , eff 2 ( ε 1 + ε 2 , eff ) 2 ,
ε 2 , eff ( 2 , TM ) ε env = ( 1 f ) ( ε 2 , eff ( 0 , TM ) ) 2 ε env 2 { 1 + π 2 3 f 2 ( 1 f ) 2 ( λ Λ ) 2 ( 1 ε 1 1 ε env ) 2 ε 2 , eff ( 0 , TM ) [ ε env 2 + 3 ε 2 , eff ( 0 , TM ) ε 2 , eff ( 0 , TE ) + 2 ε 2 , eff ( 0 , TE ) ( 1 f ) ( 1 ε 1 1 ε env ) ] }
1 ε 2 , eff , no wire = β ε SAM [ 1 exp ( d SAM d PD ) ] + γ ε env exp ( d SAM d PD ) .
Δ θ sp = Im { K SP ( 0 ) } n s ( w c ) cos θ sp = 2 n s cos θ sp ( ε 1 ε 2 , eff ε 1 + ε 2 , eff ) 3 2 ε 1 2 ( ε 1 ) 2 .

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