Light scattering on ultrathin capillaries

Enderlein, Jörg

doi:10.1016/s0030-4018(98)00685-3

Cited by 6 publications

(7 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Recent theoretical investigation on this issue suggested that the intensity of the backscattered light might be extremely low under favorable conditions. 37 We also carried out fluorescence correlation measurements inside the tip of the pipet and in the open volume to determine the diffusion constant of DNA and to address how the glass surface impedes the diffusion of ss-DNA molecules. Figure 4 shows fluorescence autocorrelation curves in different conditions.…”

Section: Resultsmentioning

confidence: 99%

Programmable Delivery of DNA through a Nanopipet

et al. 2002

View full text Add to dashboard Cite

We report the pulsed delivery of single-stranded DNA molecules through a nanopipet. The conical geometry of the pipet leads to a localized electric field, since all of the potential drop occurs in the tip region. Pulsatile delivery of DNA molecules can be achieved in an experimentally simple way with high precision by controlling the applied voltage. Single-molecule detection and fluorescence correlation spectroscopy in the nanopipet enable us to determine the number of molecules delivered. Anomalous slow diffusion of the DNA molecules in the pipet has also been observed. This nanopumping technique may have potential applications in local drug delivery and nanofabrication of biomolecules on surfaces in aqueous environments.

show abstract

Section: Resultsmentioning

confidence: 99%

Programmable Delivery of DNA through a Nanopipet

et al. 2002

View full text Add to dashboard Cite

show abstract

“…In addition, back-scattering was further reduced by mounting the ECI along the y-axis parallel to the laser polarization. 34 The capillary was aligned on the 3-D piezo stage by maximizing the back-scattering signal from the glass-air interface (see ESI †). Once the capillary inner bore was located, a sample of 100 nM Rhodamine 110 was passed through the capillary.…”

Section: Ce Integration On a Confocal Microscopementioning

confidence: 99%

Ultrasensitive on-column laser-induced fluorescence in capillary electrophoresis using multiparameter confocal detection

Mazouchi

Dodgson

Wegman

et al. 2012

Analyst

View full text Add to dashboard Cite

We report a simple method to efficiently couple on-column, standard Capillary Electrophoresis with Confocal MultiParameter Fluorescence detection (CE-CMPF) using only commercially available components. A molecular collection of 13% and a concentration limit of detection of 1.5 pM fluorescein are achieved in our instrument by gating the arrival time of individual photons in order to reduce the scattering contribution. The proposed scheme allows for amplification-free detection and separation of three different microRNAs from the MCF-7 cell lysate. The limit of detection is approximately 500 times smaller and the separation time is 3 times shorter compared to protocols based on commercial CE instrumentation. Although the optical design can be further improved, it is shown that the current CE-CMPF prototype is already capable of analyzing the microRNA content of single cells. In addition, all CE protocols previously developed for commercial instruments can be performed with our CE-CMPF without modification but with nearly 3 orders of magnitude better limit of detection.

show abstract

“…The degree of scatter depends on the angle between the excitation and collection axes and on the polarization state of the excitation light [25,26]. Figure 4 shows a plot of S/N as a function of plane of polarization of the excitation light for our system.…”

Section: Polarizationmentioning

confidence: 99%

Fundamentals and practice for ultrasensitive laser‐induced fluorescence detection in microanalytical systems

2004

View full text Add to dashboard Cite

Laser-induced fluorescence is an extremely sensitive method for detection in chemical separations. In addition, it is well-suited to detection in small volumes, and as such is widely used for capillary electrophoresis and microchip-based separations. This review explores the detailed instrumental conditions required for sub-zeptomole, sub-picomolar detection limits. The key to achieving the best sensitivity is to use an excitation and emission volume that is matched to the separation system and that, simultaneously, will keep scattering and luminescence background to a minimum. We discuss how this is accomplished with confocal detection, 90 degrees on-capillary detection, and sheath-flow detection. It is shown that each of these methods have their advantages and disadvantages, but that all can be used to produce extremely sensitive detectors for capillary- or microchip-based separations. Analysis of these capabilities allows prediction of the optimal means of achieving ultrasensitive detection on microchips.

show abstract

Light scattering on ultrathin capillaries

Cited by 6 publications

References 16 publications

Programmable Delivery of DNA through a Nanopipet

Programmable Delivery of DNA through a Nanopipet

Ultrasensitive on-column laser-induced fluorescence in capillary electrophoresis using multiparameter confocal detection

Fundamentals and practice for ultrasensitive laser‐induced fluorescence detection in microanalytical systems

Contact Info

Product

Resources

About