Sample Preparation for Lab-on-a-Chip Systems in Molecular Diagnosis: A Review

Abstract

Rapid and low-cost molecular analysis is especially required for early and specific diagnostics, quick decision-making, and sparing patients from unnecessary tests and hospitals from extra costs. One way to achieve this objective is through automated molecular diagnostic devices. Thus, sample-to-answer microfluidic devices are emerging with the promise of delivering a complete molecular diagnosis system that includes nucleic acid extraction, amplification, and detection steps in a single device. The biggest issue in such equipment is the extraction process, which is normally laborious and time-consuming but extremely important for sensitive and specific detection. Therefore, this Review focuses on automated or semiautomated extraction methodologies used in lab-on-a-chip devices. More than 15 different extraction methods developed over the past 10 years have been analyzed in terms of their advantages and disadvantages to improve extraction procedures in future studies. Herein, we are able to explain the high applicability of the extraction methodologies due to the large variety of samples in which different techniques were employed, showing that their applications are not limited to medical diagnosis. Moreover, we are able to conclude that further research in the field would be beneficial because the methodologies presented can be affordable, portable, time efficient, and easily manipulated, all of which are strong qualities for point-of-care technologies.

Clustered Regularly Interspaced short palindromic repeats‐Based Microfluidic System in Infectious Diseases Diagnosis: Current Status, Challenges, and Perspectives

“…[ 23 ] Therefore, pathogen enrichment and matrix removal are essential for effectively detecting CRISPR‐based microfluidic platforms, particularly for clinical or environmental samples with low pathogen concentrations and complex constituents. [ 24 , 25 ] Although conventional sample pretreatment is implemented in the centralized laboratory, the microfluidic technique represents a simplified alternative, such as employing a filtration step without a centrifuge. Cell lysis to release target analytes is a crucial step that can be integrated into microfluidic devices through thermal, chemical, enzymatic, mechanical, and electrical treatments, according to the acquired quality of extraction and sample type.…”

Reversible Thermally-Responsive Copolymer Valve for Manipulating Water Wicking

“…Wicking is a ubiquitous dynamic wetting process in which capillary force drives liquid flow in porous systems. , With the development of high technology, such as thermal management materials, − lab-on-a-chip , and electronic devices, , the complex and diverse application environment also puts more demands on the innovation of technology. Since wicking possesses miniaturization ability, simple equipment, and does not require external energy supply, it has been widely utilized in phase change boiling heat transfer, − water harvesting in arid environments, , moisture wicking wearable equipment, − micro biochemical testing platforms, and microfluid manipulation equipment. , In particular, wicking phenomena have become the hot direction of microfluidic manipulation technology development, such as precise one-dimensional fluid manipulation, two-dimensional planes for fluid collection, and dynamic liquid filling and mixing .…”

3D-Printed Microfluidic Chip for Real-Time Glucose Monitoring in Liquid Analytes

“…Microfluidics deals with the control and manipulation of fluids on a sub-millimeter scale in a single or network of microchannels [ 1 , 2 , 3 , 4 , 5 ]. With the development of technology, microfluidics is becoming a part of the complex miniaturized systems called Lab-on-a-Chip (LOC) [ 6 , 7 , 8 ] that contain multiple operations integrated into one single chip, such as reagent mixing [ 9 ], particle separation [ 10 ], DNA extraction and amplification [ 11 ], detection [ 12 ], etc. Recent studies demonstrate that LOC systems had found application in various point-of-care analyses such as the detection of foodborne pathogenic bacteria in food quality control [ 13 , 14 , 15 ], environmental monitoring [ 16 , 17 ], and biomarker detection [ 18 , 19 ], or could be used for developing an organ-on-chip for in vitro analysis [ 20 , 21 ].…”