High-speed RNA microextraction technology using magnetic oligo-dT beads and lateral magnetophoresis

Abstract

This paper presents a high-speed RNA microextractor for the direct isolation of RNA from peripheral blood lysate using magnetic oligo-dT beads. The extraction is achieved through lateral magnetophoresis, generated by a ferromagnetic wire array inlaid on a glass substrate. This RNA microextractor separated more than 80% of magnetic beads with a flow rate up to 20 ml h(-1), and the overall extraction procedure was completed within 1 min. The absorbance ratio of RNA to protein (A(260)/A(280)) was >1.7, indicating that the extraction technology yielded nearly pure RNA. The feasibility of this technique was evaluated further for its applicability to reverse transcription polymerase chain reaction (RT-PCR) procedures by performing cDNA synthesis and PCR. The analysis verified that the RNA microextractor is a practical method for easy, rapid, and high-precision RT-PCR using minimal reagent volumes without requiring highly trained personnel. In addition, it can be readily incorporated into genetic analysis procedures for realizing automated on-chip genetic platforms in a micro format.

Nanotechnology for the detection and kill of circulating tumor cells

“…It is an easy, rapid, and accurate method to separate RNA and tumor cells [51-53]. Herein, we introduce a novel CTC separation device applying the lateral magnetophoresis principle designed by Kim et al [23].…”

Combination of dynamic magnetophoretic separation and stationary magnetic trap for highly sensitive and selective detection of Salmonella typhimurium in complex matrix

“…The basic principle of this method is to control the flow direction of magnetic beads by manipulating the magnetic force against the hydrodynamic force (Pamme et al, 2006b;Pamme, 2007;Jung and Han, 2008). Recent magnetophoretic devices, utilized immunomagnetic beads to target antigens of interest, have applied to cell sorting (Adams et al, 2008), RNA microextraction (Lee et al, 2010), aptamers selection (Lou et al, 2009;Cho et al, 2010), circulating tumor cell separation (Plouffe et al, 2011;Kim et al, 2013), and virion capture (Chen et al, 2010). While most of the magnetophoretic devices are just used as separators, the following detection conducted off chip may cause the loss of samples, which would have an impact on the accuracy of the detection.…”

Track‐Etched Magnetic Micropores for Immunomagnetic Isolation of Pathogens

“…Much work has been done to develop and improve magnetic isolation using microfabrication techniques . Micropatterned magnetic field profiles have been engineered using lithographically defined current carrying wires and magnetic materials . Additionally, a number of bottom‐up fabrication strategies have been developed to create strong magnetic forces without lithography .…”