Limits...
Localized Surface Plasmon Resonance Biosensing: Current Challenges and Approaches.

Unser S, Bruzas I, He J, Sagle L - Sensors (Basel) (2015)

Bottom Line: In this article, we have categorized these challenges into four categories: improving sensitivity and limit of detection, selectivity in complex biological solutions, sensitive detection of membrane-associated species, and the adaptation of sensing elements for point-of-care diagnostic devices.The following section will describe various LSPR platforms designed for the sensitive detection of membrane-associated species.Finally, recent advances towards multiplexed and microfluidic LSPR-based devices for inexpensive, rapid, point-of-care diagnostics will be discussed.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry, College of Arts and Sciences, University of Cincinnati, 301 West Clifton Court, Cincinnati, OH 45221-0172, USA. unsersa@mail.uc.edu.

ABSTRACT
Localized surface plasmon resonance (LSPR) has emerged as a leader among label-free biosensing techniques in that it offers sensitive, robust, and facile detection. Traditional LSPR-based biosensing utilizes the sensitivity of the plasmon frequency to changes in local index of refraction at the nanoparticle surface. Although surface plasmon resonance technologies are now widely used to measure biomolecular interactions, several challenges remain. In this article, we have categorized these challenges into four categories: improving sensitivity and limit of detection, selectivity in complex biological solutions, sensitive detection of membrane-associated species, and the adaptation of sensing elements for point-of-care diagnostic devices. The first section of this article will involve a conceptual discussion of surface plasmon resonance and the factors affecting changes in optical signal detected. The following sections will discuss applications of LSPR biosensing with an emphasis on recent advances and approaches to overcome the four limitations mentioned above. First, improvements in limit of detection through various amplification strategies will be highlighted. The second section will involve advances to improve selectivity in complex media through self-assembled monolayers, "plasmon ruler" devices involving plasmonic coupling, and shape complementarity on the nanoparticle surface. The following section will describe various LSPR platforms designed for the sensitive detection of membrane-associated species. Finally, recent advances towards multiplexed and microfluidic LSPR-based devices for inexpensive, rapid, point-of-care diagnostics will be discussed.

No MeSH data available.


Size-selective sensing of colloidal nanoparticles with 200 nm Au-Ag nanobowl arrays. For nanoparticles small enough to fit into the nanobowls, a large increase in LSPR shift, (a) and SERS intensity; (b) is observed; (c) Scanning electron microscopy images showing the smaller nanoparticles often reside inside the nanobowls, whereas the nanoparticles too large to fit in the nanobowls reside either on top or alongside (unpublished results) [103].
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4541850&req=5

sensors-15-15684-f004: Size-selective sensing of colloidal nanoparticles with 200 nm Au-Ag nanobowl arrays. For nanoparticles small enough to fit into the nanobowls, a large increase in LSPR shift, (a) and SERS intensity; (b) is observed; (c) Scanning electron microscopy images showing the smaller nanoparticles often reside inside the nanobowls, whereas the nanoparticles too large to fit in the nanobowls reside either on top or alongside (unpublished results) [103].

Mentions: Although nanoporous films and polymers have proven effective for the selective detection of small molecules and proteins, their effect is limited with larger species such as viruses and bacterial cells. Towards the size-selective detection of larger species, a recent study in the Sagle group has taken a different approach to size-selectivity. Instead of incorporating size-selectivity into the self-assembled monolayer on the nanoparticle surface, the shape of the nanoparticle itself was used to select a species of a given size. In this work, gold-silver nanobowls of tunable size were fabricated through the galvanic ion replacement [101] of a silver nanoparticle array made using hole-mask colloidal lithography [102]. A proof-of-concept experiment was carried out by binding gold colloids of a given size to the resulting nanobowl arrays. It was found that when the gold colloids were small enough to enter the interior of the nanobowls, increased LSPR frequency shifts and SERS signal resulted, see Figure 4. These size-selective nanobowls were then used to detect the 95 nm H1N1 virus.


Localized Surface Plasmon Resonance Biosensing: Current Challenges and Approaches.

Unser S, Bruzas I, He J, Sagle L - Sensors (Basel) (2015)

Size-selective sensing of colloidal nanoparticles with 200 nm Au-Ag nanobowl arrays. For nanoparticles small enough to fit into the nanobowls, a large increase in LSPR shift, (a) and SERS intensity; (b) is observed; (c) Scanning electron microscopy images showing the smaller nanoparticles often reside inside the nanobowls, whereas the nanoparticles too large to fit in the nanobowls reside either on top or alongside (unpublished results) [103].
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4541850&req=5

sensors-15-15684-f004: Size-selective sensing of colloidal nanoparticles with 200 nm Au-Ag nanobowl arrays. For nanoparticles small enough to fit into the nanobowls, a large increase in LSPR shift, (a) and SERS intensity; (b) is observed; (c) Scanning electron microscopy images showing the smaller nanoparticles often reside inside the nanobowls, whereas the nanoparticles too large to fit in the nanobowls reside either on top or alongside (unpublished results) [103].
Mentions: Although nanoporous films and polymers have proven effective for the selective detection of small molecules and proteins, their effect is limited with larger species such as viruses and bacterial cells. Towards the size-selective detection of larger species, a recent study in the Sagle group has taken a different approach to size-selectivity. Instead of incorporating size-selectivity into the self-assembled monolayer on the nanoparticle surface, the shape of the nanoparticle itself was used to select a species of a given size. In this work, gold-silver nanobowls of tunable size were fabricated through the galvanic ion replacement [101] of a silver nanoparticle array made using hole-mask colloidal lithography [102]. A proof-of-concept experiment was carried out by binding gold colloids of a given size to the resulting nanobowl arrays. It was found that when the gold colloids were small enough to enter the interior of the nanobowls, increased LSPR frequency shifts and SERS signal resulted, see Figure 4. These size-selective nanobowls were then used to detect the 95 nm H1N1 virus.

Bottom Line: In this article, we have categorized these challenges into four categories: improving sensitivity and limit of detection, selectivity in complex biological solutions, sensitive detection of membrane-associated species, and the adaptation of sensing elements for point-of-care diagnostic devices.The following section will describe various LSPR platforms designed for the sensitive detection of membrane-associated species.Finally, recent advances towards multiplexed and microfluidic LSPR-based devices for inexpensive, rapid, point-of-care diagnostics will be discussed.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry, College of Arts and Sciences, University of Cincinnati, 301 West Clifton Court, Cincinnati, OH 45221-0172, USA. unsersa@mail.uc.edu.

ABSTRACT
Localized surface plasmon resonance (LSPR) has emerged as a leader among label-free biosensing techniques in that it offers sensitive, robust, and facile detection. Traditional LSPR-based biosensing utilizes the sensitivity of the plasmon frequency to changes in local index of refraction at the nanoparticle surface. Although surface plasmon resonance technologies are now widely used to measure biomolecular interactions, several challenges remain. In this article, we have categorized these challenges into four categories: improving sensitivity and limit of detection, selectivity in complex biological solutions, sensitive detection of membrane-associated species, and the adaptation of sensing elements for point-of-care diagnostic devices. The first section of this article will involve a conceptual discussion of surface plasmon resonance and the factors affecting changes in optical signal detected. The following sections will discuss applications of LSPR biosensing with an emphasis on recent advances and approaches to overcome the four limitations mentioned above. First, improvements in limit of detection through various amplification strategies will be highlighted. The second section will involve advances to improve selectivity in complex media through self-assembled monolayers, "plasmon ruler" devices involving plasmonic coupling, and shape complementarity on the nanoparticle surface. The following section will describe various LSPR platforms designed for the sensitive detection of membrane-associated species. Finally, recent advances towards multiplexed and microfluidic LSPR-based devices for inexpensive, rapid, point-of-care diagnostics will be discussed.

No MeSH data available.