Recent developments in detection methods for microfabricated analytical devices

Schwarz, Maria A.; Hauser, Peter C.

doi:10.1039/b103795c

Cited by 276 publications

(212 citation statements)

References 85 publications

Supporting

Mentioning

207

Contrasting

Unclassified

Order By: Relevance

“…[6][7][8][9] In contrast to fluorescence-based detection, SERS detection produces a fingerprint spectrum of the detected analyte, which enables molecules to be detected without labelling. Furthermore, this narrowband spectral fingerprint enables multi-analyte detection with a single laser source and filter set, 10 which is generally not feasible using fluorescence detection. Nonetheless, SERS continues to be limited to applications in research labs today.…”

Section: Introductionmentioning

confidence: 99%

“…However, in the case of SERS, this can hurt the detection limit as compared to conventional techniques because of the reduced sample volume and the diffusion-limited transport of analyte molecules within the channel. 10,11 To overcome these barriers, a number of reports have demonstrated improved performance of SERS in microsystems by leveraging the principles of optofluidics, which is defined by the synergistic integration of photonics and microfluidics. [12][13][14][15] In one example of an optofluidic SERS technique, photonic crystal waveguides maximize the interaction of the excitation laser light with nanoparticle-analyte conjugates.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

A nanoporous optofluidic microsystem for highly sensitive and repeatable surface enhanced Raman spectroscopy detection

Yazdi

White

2012

Biomicrofluidics

View full text Add to dashboard Cite

We report the demonstration of an optofluidic surface enhanced Raman spectroscopy (SERS) device that leverages a nanoporous microfluidic matrix to improve the SERS detection performance by more than two orders of magnitude as compared to a typical open microfluidic channel. Although it is a growing trend to integrate optical biosensors into microfluidic channels, this basic combination has been detrimental to the sensing performance when applied to SERS. Recently, however, synergistic combinations between microfluidic functions and photonics (i.e., optofluidics) have been implemented that improve the detection performance of SERS. Conceptually, the simplest optofluidic SERS techniques reported to date utilize a single nanofluidic channel to trap nanoparticle-analyte conjugates as a method of preconcentration before detection. In this work, we leverage this paradigm while improving upon the simplicity by forming a 3D nanofluidic network with packed nanoporous silica microspheres in a microfluidic channel; this creates a concentration matrix that traps silver nanoclusters and adsorbed analytes into the SERS detection volume. With this approach, we are able to achieve a detection limit of 400 attomoles of Rhodamine 6G after only 2 min of sample loading with high chip-to-chip repeatability. Due to the high number of fluidic paths in the nanoporous channel, this approach is less prone to clogging than single nanofluidic inlets, and the loading time is decreased compared to previous reports. In addition, fabrication of this microsystem is quite simple, as nanoscale fabrication is not necessary. Finally, integrated multimode fiber optic cables eliminate the need for optical alignment, and thus the device is relevant for portable and automated applications in the field, including point-of-sample and point-of-care detection. To illustrate a relevant field-based application, we demonstrate the detection of 12 ppb of the organophosphate malathion in water using the nanofluidic SERS microsystem.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

A nanoporous optofluidic microsystem for highly sensitive and repeatable surface enhanced Raman spectroscopy detection

Yazdi

White

2012

Biomicrofluidics

View full text Add to dashboard Cite

show abstract

“…Capillary electrophoresis (CE) separation is a powerful method over a broad range of molecular sizes, thanks to flexible MF protocols, exploiting a variety of sieving gel matrices. The inherent advantages of MF CE, high-speed operation and low reagent volumes, can be combined with laser-induced fluorescence (LIF) detection [6][7][8] Furthermore, the spatio-temporal resolution provided by integrated waveguide excitation 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 F o r P e e r R e v i e w 4 can allow for a 20-fold improvement in accuracy if better MF CE separation protocols become available.…”

Section: Introductionmentioning

confidence: 99%

High‐resolution electrophoretic separation and integrated‐waveguide excitation of fluorescent DNA molecules in a lab on a chip

Dongre

Weerd²,

Besselink

et al. 2010

Electrophoresis

View full text Add to dashboard Cite

show abstract

“…The focus will be on work published in the last 2 years and this review is not inferred to be comprehensive. The methods we term as "conventional" -LIF, all electrochemical (EC) detection methods (amperometric, conductivity, potentiometry), and MS -will not be covered here and the reader is referred to several general microfluidic review articles covering these [8][9][10][11][12], as well as many reviews that focus entirely on detection [13][14][15].…”

Section: Introductionmentioning

confidence: 99%

Unconventional detection methods for microfluidic devices

2006

View full text Add to dashboard Cite

The direction of modern analytical techniques is to push for lower detection limits, improved selectivity and sensitivity, faster analysis time, higher throughput, and more inexpensive analysis systems with ever-decreasing sample volumes. These very ambitious goals are exacerbated by the need to reduce the overall size of the device and the instrumentation -the quest for functional micrototal analysis systems epitomizes this. Microfluidic devices fabricated in glass, and more recently, in a variety of polymers, brings us a step closer to being able to achieve these stringent goals and to realize the economical fabrication of sophisticated instrumentation. However, this places a significant burden on the detection systems associated with microchip-based analysis systems. There is a need for a universal detector that can efficiently detect sample analytes in real time and with minimal sample manipulation steps, such as lengthy labeling protocols. This review highlights the advances in uncommon or less frequently used detection methods associated with microfluidic devices. As a result, the three most common methods -LIF, electrochemical, and mass spectrometric techniques -are omitted in order to focus on the more esoteric detection methods reported in the literature over the last 2 years.

show abstract

Recent developments in detection methods for microfabricated analytical devices

Cited by 276 publications

References 85 publications

A nanoporous optofluidic microsystem for highly sensitive and repeatable surface enhanced Raman spectroscopy detection

A nanoporous optofluidic microsystem for highly sensitive and repeatable surface enhanced Raman spectroscopy detection

High‐resolution electrophoretic separation and integrated‐waveguide excitation of fluorescent DNA molecules in a lab on a chip

Unconventional detection methods for microfluidic devices

Contact Info

Product

Resources

About