Direct DNA Analysis with Paper-Based Ion Concentration Polarization

Abstract

DNA analysis is essential for diagnosis and monitoring of many diseases. Conventional DNA testing is generally limited to the laboratory. Increasing access to relevant technologies can improve patient care and outcomes in both developed and developing regions. Here, we demonstrate direct DNA analysis in paper-based devices, uniquely enabled by ion concentration polarization at the interface of patterned nanoporous membranes in paper (paper-based ICP). Hepatitis B virus DNA targets in human serum are simultaneously preconcentrated, separated, and detected in a single 10 min operation. A limit of detection of 150 copies/mL is achieved without prior viral load amplification, sufficient for early diagnosis of hepatitis B. We clinically assess the DNA integrity of sperm cells in raw human semen samples. The percent DNA fragmentation results from the paper-based ICP devices strongly correlate (R(2) = 0.98) with the sperm chromatin structure assay. In all cases, agreement was 100% with respect to the clinical decision. Paper-based ICP can provide inexpensive and accessible advanced molecular diagnostics.

Recent advances in enhancing the sensitivity of electrophoresis and electrochromatography in capillaries and microchips (2014–2016)

“…Nafion has been widely used in μPAD for sample preconcentration . Phan and coworkers developed a μPAD by simply integrating microporous paper and nanoporous nafion membrane and then laminating with plastic film without printing hydrophobic materials such as wax, the schematic was shown in Fig.…”

“…Gong et al. demonstrated direct DNA analysis in a μPAD with a patterned Nafion™ membrane . Hepatitis B virus DNA fragments were simultaneously preconcentrated, separated, and detected in 10 min with a LOD of 150 copies/mL without prior viral local amplification.…”

Lab-on-a-Chip Technologies for the Single Cell Level: Separation, Analysis, and Diagnostics

“…One very prominent aspect of microfluidic research is diagnostics on the single-cell or even molecular level. The significance of recent research towards microfluidics-based single cell diagnostic chips is apparent in health care, in our homes, and also very prominently in the fight against the COVID 19 pandemic: The diagnostic targets range from circulating tumor cells (CTC) [1][2][3][4][5][6], over parasites in blood [7][8][9][10][11][12][13][14][15], male fertility [16][17][18][19][20], molecular markers for infections [11,15,[21][22][23], cells of a specific stage in their life cycle [24,25], plant pathogens [26] and the SARS-CoV-2 proteome [27][28][29][30][31][32]. Depending on the exact target (either the entire cell or sub-cellular markers) there are different approaches to on-chip detection, each with their own underlying fundamentals and set of limitations.…”

Folding-paper-based preconcentrator for low dispersion of preconcentration plug

“…Ion concentration polarization (ICP) phenomena, wherein ion concentrations are distributed at the interface between an ion exchange membrane (IEM) and an electrolyte having an electric potential [1], are intensively studied in the field of micro/nanofluidics [2][3][4][5][6]. In general, ICP occurs near an IEM via the permeation of specific charged ions (cation or anion).…”