Volumetric micro-injector for capillary electrophoresis

US11209390B2 · kind B2 · utility

Assignee

• The Regents of the University of California · US

Inventors

• Noel S. Ha · Los Angeles, US
• R. Michael Van Dam · Los Angeles, US
• Jimmy Ly · San Francisco, US

Key dates

• Filing date: Oct 6, 2017
• Grant date: Dec 28, 2021
• Expiry date: Dec 3, 2037

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B01L2400/0487
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A volumetric microfluidic injector for capillary electrophoresis (CE) for highly repeatable sample injection has been designed and built to eliminate known injection bias in hydrodynamic injection. A defined volume from 1-10 nL or 0.1-100 nL of sample is confined in a defined region of a micro-valve PDMS microfluidic injector chip and electrophoretic potential is applied to drive sample into a separation device such as an embedded fused silica capillary for separation and detection. Using a 75 μm ID capillary, the RSD of an absorbance peak area as low as 1.32% (n=11) is obtained. As a comparison, the time-dependent injection was tested using the same chip which resulted in an inferior repeatability.