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

Abstract

Nucleic acid (NA) extraction is a basic step for genetic analysis, from scientific research to diagnostic and forensic applications. It aims at preparing samples for its application with biomolecular technologies such as isothermal and non-isothermal amplification, hybridization, electrophoresis, Sanger sequencing and next-generation sequencing. Multiple steps are involved in NA collection from raw samples, including cell separation from the rest of the specimen, cell lysis, NA isolation and release. Typically, this process needs molecular biology facilities, specialized instrumentation and labor-intensive operations. Microfluidic devices have been developed to analyze NA samples with high efficacy and sensitivity. In this context, the integration within the chip of the sample preparation phase is crucial to leverage the promise of portable, fast, user-friendly and economic point-of-care solutions. This review presents an overview of existing lab-on-a-chip (LOC) solutions designed to provide automated NA extraction from human raw biological fluids, such as whole blood, excreta (urine and feces), saliva. It mainly focuses on LOC implementation aspects, aiming to describe a detailed panorama of strategies implemented for different human raw sample preparations.

Electricity-free nucleic acid extraction method from dried blood spots on filter paper for point-of-care diagnostics

“…In addition, given the reported applicability of FTA cards for sample preservation and NAE, we expect that the proposed methods will be compatible with other fluid samples such as buccal swabs, faecal swabs, urine or saliva. 39 Since we have also demonstrated a sample-to-result proof-of-concept workflow through the combination of the eluted disk method with colorimetric LAMP, we hope that both elute disk and in-situ disk could be used at the POC once embedded in a portable diagnostic format. 40 Furthermore, we envision that once integrated they could be applied for sample archiving and improve the current pipeline for POC diagnostics where a massive number of tests are performed with loss of data.…”

The Combination of Electrochemistry and Microfluidic Technology in Drug Metabolism Studies

“…Also, the metabolites are generated and detected in just a few minutes. [ 91 , 92 ] Furthermore, the online coupling of chip to MS provides an easy and automated procedure. As a consequence, microfluidic electrochemistry has potential applications during the early stages of drug development and discovery, where fast screening is highly required to select the best possible candidates and test compounds at low concentrations.…”

Progress of Microfluidic Continuous Separation Techniques for Micro-/Nanoscale Bioparticles

“…Biological assays using deoxyribonucleic acid (DNA) and/or ribonucleic acid (RNA) are very important in the process of isolating/purifying nucleic acids from complex biosamples, such as cell lysates for high-sensitivity biosensing, such as forensic analysis [ 44 ] and disease diagnosis [ 45 ]. The diameter of DNA is approximately 2~3 nm, and the length varies depending on the size of the fragment, but it can be up to few meters long.…”

“…The two-dimensional map, as shown in Figure 5 A(iii), was constructed using a microfluidic EP device with only 3 μL of sample and a 7 min time period, which is a few orders of magnitude faster than conventional two-dimensional protein gel electrophoresis. In addition to protein analysis, microfluidic EP devices are utilized for various bioparticle manipulations, such as bacterial focusing/immobilization [ 156 ], micro-RNA/DNA separation, fingerprinting [ 45 ], and drug analysis [ 157 ].…”