Silicon Nanowire Arrays for Ultrasensitive Label-Free Detection of DNA
10 Jun 2007-pp 2003-2006
TL;DR: In this article, the authors investigated the field effect of SiNW arrays in terms of the change in charge density at the SiNW surface after hybridization, the so-called field effect.
Abstract: Arrays of highly ordered silicon nanowires (SiNWs) are fabricated using complementary metal-oxide semiconductor (CMOS) compatible technology and their applications in biosensors are investigated. The SiNW arrays show a concentration-dependent resistance change upon hybridization to complementary target DNA. As in the case of other SiNW biosensing devices, the sensing mechanism can be understood in terms of the change in charge density at the SiNW surface after hybridization, the so called "field effect". The SiNW arrays discriminate satisfactorily against mismatched target DNA.
Citations
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TL;DR: The approach shows potential of eliminating the demand for laborious methods by integrating the SiNW sensor with RT-PCR based on silicon technology platform and this system-scale integration for a point-of-care medical device will facilitate the diagnostic applications.
Abstract: The paper presents an innovative silicon nanowire (SiNW)-based sensor for highly sensitive and rapid detection of reverse-transcription-polymerase chain reaction (RT-PCR) product of Dengue serotype 2 (DEN-2). A specific peptide nucleic acid (PNA) was covalently attached onto the SiNW surface. A complementary fragment of DEN-2 (69 bp) was obtained through one-step RT-PCR amplification, and applied to the PNA-functionalized SiNW. The hybridization event was verified by measuring the resistance change of the SiNW before and after binding of the RT-PCR product of DEN-2 to the PNA sequence. It is found that the SiNW sensor can detect below 10 fM concentration of the amplicons within 30 min. The approach shows potential of eliminating the demand for laborious methods by integrating the SiNW sensor with RT-PCR based on silicon technology platform. Consequently, this system-scale integration for a point-of-care medical device will facilitate the diagnostic applications.
209 citations
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TL;DR: The current technology status for realizing the GAA NW device structures and their applications in logic circuit and nonvolatile memories are reviewed and the challenges and opportunities are outlined.
Abstract: Nanowire (NW) devices, particularly the gate-all-around (GAA) CMOS architecture, have emerged as the front-runner for pushing CMOS scaling beyond the roadmap. These devices offer unique advantages over their planar counterparts which make them feasible as an option for 22 -nm and beyond technology nodes. This paper reviews the current technology status for realizing the GAA NW device structures and their applications in logic circuit and nonvolatile memories. We also take a glimpse into applications of NWs in the ldquomore-than-Moorerdquo regime and briefly discuss the application of NWs as biochemical sensors. Finally, we summarize the status and outline the challenges and opportunities of the NW technology.
154 citations
Cites background from "Silicon Nanowire Arrays for Ultrase..."
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TL;DR: Changes in the global environment, including virus, vector and human behavior, will continue to influence the spectrum of viruses to which humans are exposed and their potential impact on target-focused, nucleic acid-based diagnostic tests will be considered.
Abstract: Extrapolation from recent disease history suggests that changes in the global environment, including virus, vector and human behavior, will continue to influence the spectrum of viruses to which humans are exposed. In this article, these environmental changes will be enumerated, and their potential impact on target-focused, nucleic acid-based diagnostic tests will be considered, followed by a presentation of some emerging technological responses.
8 citations
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TL;DR: It is demonstrated that 85% of the tested SiNW devices exhibit a positive threshold voltage shift after DNA hybridization, which makes way for the monolithic integration of SiNW biosensors and CMOS circuitry to realize a point of care device which can offer reliable real time electrical readout.
Abstract: Silicon nanowire (SiNW) charge based biosensors are attractive for DNA sensing applications due to their compactness and large surface-to-volume ratio. Small feature size, low production cost, repeatability, high sensitivity and selectivity are some of the key requirements for biosensors. The most common e-beam manufacturing method employed to manufacture sub-nm SiNWs is both cost and time intensive. Therefore, we propose a highly reproducible CMOS industry grade low-cost process to fabricate SiNW-based field effect transistors on 4''-wafers. The 60 nm wide SiNWs reported in this paper are fabricated using the sidewall transfer lithography process which is a self-aligned-double-patterning I-line lithography process that also facilitates encapsulation of the SiNW surface with a thin HfO2 layer on which DNA probes are grafted to finalize the biosensors. Upon DNA hybridization, SiNW devices exhibit threshold voltage shift larger than the noise introduced by the exposition to saline solutions used for the bioprocesses. More specifically, based on a statistical analysis, we demonstrate that 85% of the tested devices exhibit a positive threshold voltage shift after DNA hybridization. These promising results make way for the monolithic integration of SiNW biosensors and CMOS circuitry to realize a point of care device which can offer reliable real time electrical readout.
6 citations
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TL;DR: Novel scalable pixel-based biosensors exploiting the integration of SiNWs with CMOS in fully-depleted silicon-on-insulator technology is proposed and the first electrical results of single N and P-type SiNW pixels are presented.
Abstract: Silicon nanowires (SiNWs) are a widely used technology for sensing applications. Complementary metal-oxide-semiconductor (CMOS) integration of SiNWs advances lab-on-chip (LOC) technology and offers opportunities for read-out circuit integration, selective and multiplexed detection. In this work, we propose novel scalable pixel-based biosensors exploiting the integration of SiNWs with CMOS in fully-depleted silicon-on-insulator technology. A detailed description of the wafer-scale fabrication of SiNW pixels using the CMOS compatible sidewall-transfer-lithography as an alternative to widely investigated time inefficient e-beam lithography is presented. Each 60 nm wide SiNWs sensor is monolithically connected to a control transistor and novel on-chip fluid-gate forming an individual pixel that can be operated in two modes: biasing transistor frontgate (V G) or substrate backgate (V BG). We also present the first electrical results of single N and P-type SiNW pixels. In frontgate mode, N and P-type SiNW pixels exhibit subthreshold slope (SS) ≈ 70–80 mV/dec and I on/I off ≈ 105. The N-type and P-type pixels have an average threshold voltage, Vth of −1.7 V and 0.85 V respectively. In the backgate mode, N and P-type SiNW pixels exhibit SS ≈ 100–150 mV/dec and I on/I off ≈ 106. The N and P-type pixels have an average V th of 5 V and −2.5 V respectively. Further, the influence of the backgate and frontgate voltage on the switching characteristics of the SiNW pixels is also studied. In the frontgate mode, the V th of the SiNW pixels can be tuned at 0.2 V for 1 V change in V BG for N-type or at −0.2 V for −1 V change in V BG for P-type pixels. In the backgate mode, it is found that for stable operation of the pixels, the V G of the N and P-type transistors must be in the range 0.5–2.5 V and 0 V to −2.5 V respectively.
4 citations
References
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TL;DR: In Drosophila melanogaster a developmentally regulated precursor RNA is cleaved by an RNA interference-like mechanism to produce mature let-7 stRNA, which regulates developmental timing in Caenorhabditis elegans and probably in other bilateral animals.
Abstract: The 21-nucleotide small temporal RNA (stRNA) let-7 regulates developmental timing in Caenorhabditis elegans and probably in other bilateral animals We present in vivo and in vitro evidence that in Drosophila melanogaster a developmentally regulated precursor RNA is cleaved by an RNA interference-like mechanism to produce mature let-7 stRNA Targeted destruction in cultured human cells of the messenger RNA encoding the enzyme Dicer, which acts in the RNA interference pathway, leads to accumulation of the let-7 precursor Thus, the RNA interference and stRNA pathways intersect Both pathways require the RNA-processing enzyme Dicer to produce the active small-RNA component that represses gene expression
2,804 citations
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TL;DR: An exploration of single-walled carbon nanotubes is presented as a platform for investigating surface–protein and protein–protein binding and developing highly specific electronic biomolecule detectors for detecting clinically important biomolecules such as antibodies associated with human autoimmune diseases.
Abstract: Novel nanomaterials for bioassay applications represent a rapidly progressing field of nanotechnology and nanobiotechnology. Here, we present an exploration of single-walled carbon nanotubes as a platform for investigating surface-protein and protein-protein binding and developing highly specific electronic biomolecule detectors. Nonspecific binding on nanotubes, a phenomenon found with a wide range of proteins, is overcome by immobilization of polyethylene oxide chains. A general approach is then advanced to enable the selective recognition and binding of target proteins by conjugation of their specific receptors to polyethylene oxide-functionalized nanotubes. This scheme, combined with the sensitivity of nanotube electronic devices, enables highly specific electronic sensors for detecting clinically important biomolecules such as antibodies associated with human autoimmune diseases.
1,408 citations
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TL;DR: This work presents an elucidation of the electronic biosensing mechanisms with a newly developed microarray of nanotube "micromat" sensors and reveals that electronic effects occurring at the metal-nanotube contacts due to protein adsorption constitute a more significant contribution to the Electronic biosensing signal than adsorbed solely along the exposed lengths of the nanotubes.
Abstract: It has been reported that protein adsorption on single-walled carbon nanotube field effect transistors (FETs) leads to appreciable changes in the electrical conductance of the devices, a phenomenon that can be exploited for label-free detection of biomolecules with a high potential for miniaturization. This work presents an elucidation of the electronic biosensing mechanisms with a newly developed microarray of nanotube “micromat” sensors. Chemical functionalization schemes are devised to block selected components of the devices from protein adsorption, self-assembled monolayers (SAMs) of methoxy(poly(ethylene glycol))thiol (mPEG-SH) on the metal electrodes (Au, Pd) and PEG-containing surfactants on the nanotubes. Extensive characterization reveals that electronic effects occurring at the metal−nanotube contacts due to protein adsorption constitute a more significant contribution to the electronic biosensing signal than adsorption solely along the exposed lengths of the nanotubes.
479 citations
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TL;DR: This work provides concrete experimental evidence on the effect of SW NT-DNA binding on DNA functionality, which will help to pave the way for future designing of SWNT biocomplexes for applications in biotechnology in general and also DNA-assisted nanotube manipulation techniques.
Abstract: We report the fabrication of single-walled carbon nanotube (SWNT) DNA sensors and the sensing mechanism The simple and generic protocol for label-free detection of DNA hybridization is demonstrated with random sequence 15mer and 30mer oligonucleotides DNA hybridization on gold electrodes, instead of on SWNT sidewalls, is mainly responsible for the acute electrical conductance change due to the modulation of energy level alignment between SWNT and gold contact This work provides concrete experimental evidence on the effect of SWNT-DNA binding on DNA functionality, which will help to pave the way for future designing of SWNT biocomplexes for applications in biotechnology in general and also DNA-assisted nanotube manipulation techniques
449 citations