SNAPflex: a paper-and-plastic device for instrument-free RNA and DNA extraction from whole blood

Abstract

Nucleic acid amplification tests (NAATs), which amplify and detect pathogen nucleic acids, are vital methods to diagnose diseases, particularly in cases where patients exhibit low levels of infection. For many...

An Overview on Microfluidic Systems for Nucleic Acids Extraction from Human Raw Samples

“…This approach enables the implementation of droplet-based microdevices where, starting from sample, individual droplets are continuously formed and manipulated through the microchannels, or where a variable number of droplets of each reagent are manipulated and continuously moved upon a pathway of transportation electrodes (Figure 3). This last case is described in a recent study [22]: electrical and magnetic forces are generated to move and split droplets over the cartridge; the sequence of activation of elec- Other interesting platforms for NA extraction are represented by centrifugal-driven LOCs (or labs-on-a-disk, LODs), usually coupled with magnetic beads (details in Figure 4), electrokinetic-driven LOCs [32,65], relying on voltage application for motion by electrical gradient, and lab-on-a-paper devices, also implemented for NA extraction [40,55,56]. A recent and cost-effective innovation is microfluidic origami [83]; it is a new branch of microfluidic technology where paper can be exploited as an attractive and inexpensive platform for NA extraction [40,84] due to its intrinsic advantages such as biocompatibility, high surface area, and absorptive nature [85].…”

“…Other interesting platforms for NA extraction are represented by centrifugal-driven LOCs (or labs-on-a-disk, LODs), usually coupled with magnetic beads (details in Figure 4), electrokinetic-driven LOCs [32,65], relying on voltage application for motion by electrical gradient, and lab-on-a-paper devices, also implemented for NA extraction [40,55,56]. A recent and cost-effective innovation is microfluidic origami [83]; it is a new branch of microfluidic technology where paper can be exploited as an attractive and inexpensive platform for NA extraction [40,84] due to its intrinsic advantages such as biocompatibility, high surface area, and absorptive nature [85]. Both types, mostly based on a magnetic beads extraction or, less commonly, on silica filtration, are developed onto a rotating platform where sample and reagents motion is enabled by centrifugal and related forces (Coriolis and Euler) that, usually in combination with pneumatic forces, handle the fluidic system and enable sample processing.…”

“…The elution buffer collects NA and leads it to the desired region, to gather it or for subsequent on-chip detection aims. TE [27,31,33,36,38,39,42,43,65] Tris-HCl [40,67] Tris-KCl [9,37,45] NaOH [68] NaHCO 3 [26,58] Elution strictly depends on the pH of the solution, which enables or disables binding, and it also directly depends on the used capture matrix. DNA elution from silica matrix is performed by a hypo-osmotic solution, typically a low salt buffer or elution buffer, generally alkaline.…”

Lab-on-Paper Devices for Diagnosis of Human Diseases Using Urine Samples—A Review

“…Accordingly, many lab-on-paper platforms for the separation of whole blood samples have been proposed in recent years. Generally speaking, these devices perform the separation process using filter paper [50,51], filtration membranes [52][53][54][55], chitosan polymer structure separation [56], or combined dielectrophoretic (DEP) and capillary force separation [57]. For example, Laurenciano et al [51] fabricated a sliding hybrid PMMA/paper microchip with an integrated separation membrane to filter urine samples or separate whole blood (Figure 1b).…”

Extraction of Viral Nucleic Acids with Carbon Nanotubes Increases SARS-CoV-2 Quantitative Reverse Transcription Polymerase Chain Reaction Detection Sensitivity

“…Kolluri et al . reported a portable nucleic acid extraction protocol from whole blood with a paper-and-plastic device for capture and purification of nucleic acids on a glass fiber membrane, followed by treatment with a chromatography paper waste pad . In addition to these total nucleic acid extraction methods, affinity-based nucleic acid extraction has been also investigated by using complementary DNA or RNA sequences as capturing ligands.…”