Nanoplasmonic sensors for detecting circulating cancer biomarkers

Ferhan, Abdul Rahim,Jackman, Joshua A.,Park, Jae Hyeon,Cho, Nam-Joon,Kim, Dong-Hwan Elsevier 2018 Advanced drug delivery reviews Vol.125 No.-

<P><B>Abstract</B></P> <P>The detection of cancer biomarkers represents an important aspect of cancer diagnosis and prognosis. Recently, the concept of liquid biopsy has been introduced whereby diagnosis and prognosis are performed by means of analyzing biological fluids obtained from patients to detect and quantify circulating cancer biomarkers. Unlike conventional biopsy whereby primary tumor cells are analyzed, liquid biopsy enables the detection of a wide variety of circulating cancer biomarkers, including microRNA (miRNA), circulating tumor DNA (ctDNA), proteins, exosomes and circulating tumor cells (CTCs). Among the various techniques that have been developed to detect circulating cancer biomarkers, nanoplasmonic sensors represent a promising measurement approach due to high sensitivity and specificity as well as ease of instrumentation and operation. In this review, we discuss the relevance and applicability of three different categories of nanoplasmonic sensing techniques, namely surface plasmon resonance (SPR), localized surface plasmon resonance (LSPR) and surface-enhanced Raman scattering (SERS), for the detection of different classes of circulating cancer biomarkers.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Nanoplasmonic Ruler for Measuring Separation Distance between Supported Lipid Bilayers and Oxide Surfaces

Ferhan, Abdul Rahim,Š,pač,ková,, Barbora,Jackman, Joshua A.,Ma, Gamaliel J.,Sut, Tun Naw,Homola, Jiř,í,Cho, Nam-Joon American Chemical Society 2018 ANALYTICAL CHEMISTRY - Vol.90 No.21

<P>Unraveling the details of how supported lipid bilayers (SLBs) are coupled to oxide surfaces is experimentally challenging, and there is an outstanding need to develop highly surface-sensitive measurement strategies to determine SLB separation distances. Indeed, subtle variations in separation distance can be associated with significant differences in bilayer-substrate interaction energy. Herein, we report a nanoplasmonic ruler strategy to measure the absolute separation distance between SLBs and oxide surfaces. A localized surface plasmon resonance (LSPR) sensor was employed to track SLB formation onto titania- and silica-coated gold nanodisk arrays. To interpret measurement data, an analytical model relating the LSPR measurement response to bilayer-substrate separation distance was developed based on finite-difference time-domain (FDTD) simulations and theoretical calculations. The results indicate that there is a larger separation distance between SLBs and titania surfaces than silica surfaces, and the trend was consistent across three tested lipid compositions. We discuss these findings within the context of the interfacial forces underpinning bilayer-substrate interactions, and the nanoplasmonic ruler strategy provides the first direct experimental evidence comparing SLB separation distances on titania and silica surfaces.</P> [FIG OMISSION]</BR>

Fabrication of Plasmon-Active Polymer-Nanoparticle Composites for Biosensing Applications

Abhinay Mishra,Abdul Rahim Ferhan,Chee Meng Benjamin Ho,Joohyun Lee,Dong-Hwan Kim,Young Jin Kim,Yong-Jin Yoon 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.8 No.3

Polymer-nanoparticle composites find relevance in various fields ranging from optoelectronics to the biomedical sciences. Various efforts have been made to devise fabrication strategies that are simple, robust,and reproducible. Herein, we demonstrate a universal strategy to fabricate plasmon-active polymer-nanoparticle composites, exemplified by the incorporation of gold nanoparticles (AuNPs) into a triethylene glycol dimethacrylate (TEGDMA) polymer scaffold. The TEGDMA scaffold was synthesized on a planar glass support substrate via surface-initiated atomic transfer radical polymerization, followed by the immersion of the TEGDMA-coated glass substrate in a solution of AuNPs prepared via conventional wet-chemical synthesis. This led to the strong attachment of AuNPs to the TEGDMA nanolobes, which was confirmed by the UV absorption peak at 527 nm, due to localized surface plasmon resonance of AuNPs. More importantly, the nanolobe architecture facilitates nanoparticle trapping while allowing molecular access to the nanoparticle surface. This enabled us to further functionalize the incorporated AuNPs with thrombin binding aptamer and utilize the biofunctionalized polymer-nanoparticle composite as a thrombin sensor. The synergistic combination of metallic nanoparticles acting as a sensing module with a nonfouling polymer matrix acting both as a nonrigid scaffold and to screen biomolecules allowed the detection of thrombin with good sensitivity down to 0.01 ng/mL with a linear range over three orders of magnitude. Our work paves the way for the fabrication of reliable biomolecular sensors based on the polymer brush-nanoparticle architecture.

Gold Nanowire Bundles Grown Radially Outward from Silicon Micropillars

Huang, Youju,Ferhan, Abdul Rahim,Cho, Seok-Jin,Lee, Haiwon,Kim, Dong-Hwan American Chemical Society 2015 ACS APPLIED MATERIALS & INTERFACES Vol.7 No.32

<P>One-dimensional (1D) micro- and nanostructures have become increasingly popular because of their tremendous prospect in various applications. While the design and fabrication of these structures from a single component in two-dimensional (2D) arrays is common, the attainment of hierarchical three-dimensional (3D) architectures made up of multicomponent one-dimensional structures is rare. Herein we report, for the first time, the lateral growth of gold nanowires from the sidewalls of substrate grown silicon micropillars to form a unique 'wire-on-pillar' architecture. Unlike zero-dimensional (OD) point-like, 1D linear, and 2D planar Au structures, the obtained 3D 'wire-on-pillar' Au architecture provides abundant hotspots between adjacent Au wires, which led to remarkably high surface-enhanced Raman scattering (SERS) signals.</P>

A Strategy for the Formation of Gold–Palladium Supra-Nanoparticles from Gold Nanoparticles of Various Shapes and Their Application to High-Performance H₂O₂ Sensing

Huang, Youju,Ferhan, Abdul Rahim,Dandapat, Anirban,Yoon, Chong Seung,Song, Ji Eun,Cho, Eun Chul,Kim, Dong-Hwan American Chemical Society 2015 The Journal of Physical Chemistry Part C Vol.119 No.46

<P>We present a new approach for the synthesis of gold (Au)–palladium (Pd) bimetallic supra-nanoparticles in which densely packed anisotropic Pd nanostructures surround a central Au nanoparticle (rod, sphere, cubic shape). They were obtained by means of Pd crystal growth on Au nanoparticle surfaces which are modified with a mixture of cetyltrimethylammonium bromide (CTAB) and 5-bromosalicylic acid (5-BrSA). From a comparative study with a Au nanorod (NR) as a seed, the use of the CTAB/5-BrSA mixture plays a pivotal role in obtaining such unique supra-structures; the Au NR capped with only CTAB resulted in Au core–continuous Pd shell nanoparticles instead. The Au–Pd supra-nanoparticles provide active surface area for electrocatalytic activities higher than that of the Au@Pd continuous shell nanoparticles, displaying outstanding performance for mediator-free electrochemical detection of H<SUB>2</SUB>O<SUB>2</SUB>.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jpccck/2015/jpccck.2015.119.issue-46/acs.jpcc.5b08423/production/images/medium/jp-2015-08423b_0008.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/jp5b08423'>ACS Electronic Supporting Info</A></P>

Temperature-Induced Denaturation of BSA Protein Molecules for Improved Surface Passivation Coatings

Park, Jae Hyeon,Jackman, Joshua A.,Ferhan, Abdul Rahim,Ma, Gamaliel Junren,Yoon, Bo Kyeong,Cho, Nam-Joon American Chemical Society 2018 ACS APPLIED MATERIALS & INTERFACES Vol.10 No.38

<P>Bovine serum albumin (BSA) is the most widely used protein for surface passivation applications, although it has relatively weak, nonsticky interactions with hydrophilic surfaces such as silica-based materials. Herein, we report a simple and versatile method to increase the stickiness of BSA protein molecules adsorbing onto silica surfaces, resulting in up to a 10-fold improvement in blocking efficiency against serum biofouling. Circular dichroism spectroscopy, dynamic light scattering, and nanoparticle tracking analysis showed that temperature-induced denaturation of BSA proteins in bulk solution resulted in irreversible unfolding and protein oligomerization, thereby converting weakly adhesive protein monomers into a more adhesive oligomeric form. The heat-treated, denatured BSA oligomers remained stable after cooling. Room-temperature quartz crystal microbalance-dissipation and localized surface plasmon resonance experiments revealed that denatured BSA oligomers adsorbed more quickly and in larger mass quantities onto silica surfaces than native BSA monomers. We also determined that the larger surface contact area of denatured BSA oligomers is an important factor contributing to their more adhesive character. Importantly, denatured BSA oligomers were a superior passivating agent to inhibit biofouling on silica surfaces and also improved Western blot application performance. Taken together, the findings demonstrate how temperature-induced denaturation of BSA protein molecules can lead to improved protein-based coatings for surface passivation applications.</P> [FIG OMISSION]</BR>

Dimensional comparison between amplitude-modulation atomic force microscopy and scanning ion conductance microscopy of biological samples

Kim, Joonhui,Choi, MyungHoon,Jung, Goo-Eun,Ferhan, Abdul Rahim,Cho, Nam-Joon,Cho, Sang-Joon Institute of Pure and Applied Physics 2016 Japanese Journal of Applied Physics Vol. No.

<P>The range of scanning probe microscopy (SPM) applications for atomic force microscopy (AFM) is expanding in the biological sciences field, reflecting an increasing demand for tools that can improve our fundamental understanding of the physics behind biological systems. However, the complexity associated with applying SPM techniques in biomedical research hampers the full exploitation of its capabilities. Recently, the development of scanning ion conductance microscopy (SICM) has overcome these limitations and enabled contact-free, high resolution imaging of live biological specimens. In this work, we demonstrate the limitation of AFM for imaging biological samples in liquid due to artifacts arising from AFM tip-sample interaction, and how SICM imaging is able to overcome those limitations with contact-free scanning. We also demonstrate that SICM measurements, when compared to AFM, show better fit to the actual dimensions of the biological samples. Our results highlight the superiority of SICM imaging, enabling it to be widely adopted as a general and versatile research tool for biological studies in the nanoscale. (C) 2016 The Japan Society of Applied Physics</P>