Smart materials for point-of-care testing: From sample extraction to analyte sensing and readout signal generator

Sample Preparation and Diagnostic Methods for a Variety of Settings: A Comprehensive Review

“…This has led to the increased use and development of diagnostic methods to streamline the process and improve patient outcomes by decreasing the time needed to identify the cause of an infection, determine whether it is a resistant strain, and adjust patient treatment [ 27 , 28 , 29 ]. This vast range of techniques and their utility in identifying not only infectious diseases but also non-transmissible conditions can be attributed to the progress in technologies that support precision medicine over the last decade, including advances in microfluidic devices [ 30 , 31 , 32 , 33 , 34 ], next-generation sequencing (NGS) and nucleic acid amplification (NAA) methods [ 35 , 36 , 37 , 38 ], mass spectrometry (MS) techniques [ 29 , 38 , 39 , 40 ], laboratory automation [ 41 ], power sources for medical devices [ 42 ], smart materials and nanomaterials for imaging and sensing [ 8 , 43 , 44 , 45 ], biosensing technologies [ 34 , 43 , 46 , 47 , 48 , 49 , 50 ], smart devices for providing mobile power sources and computing power [ 50 , 51 , 52 , 53 ], data analysis techniques such as machine learning (ML) [ 54 , 55 , 56 , 57 ], and improved modeling of disease spread [ 58 ].…”

“…Since much of this sample preparation process is either impractical for use in POCT methods or has a much longer turnaround time as well as less sensitivity and specificity than biochemical or molecular diagnostic laboratory methods, many of the methods developed over the past decade have focused on either making the extraction and separation steps compatible with POC platforms or increasing the sample throughput of biochemical and molecular diagnostic methods used in clinical laboratory platforms [ 21 , 24 , 25 , 26 , 27 , 28 , 29 , 38 , 39 , 41 , 46 , 66 , 70 ]. As previously mentioned, the large number of advances in areas such as microfluidics, advanced materials, and biosensors, as well as the growing ubiquity of smartphones, has greatly supplemented this process for POC devices and methods while advances in laboratory automation, extractions and separations, and high-throughput assay platforms, such as microplates, have analogously supplemented the process for centralized laboratory methods, as shown in Figure 4 [ 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 67 , 68 , 69 , 70 , 71 , 72 , 73 ]. For molecular methods, including NAATs in particular, the greatest bottleneck in this process usually consists of extracting the target biomarkers by lysing the pathogens in a collected sample and separating or purifying the target analytes in order to proceed to amplification or detection [ 26 , ...…”

“…DNA and RNA-based biorecognition elements have grown in usage for similar reasons due to the specificity and large number of DNA and RNA probes available, as well as being easily multiplexed for screening [ 49 , 83 , 84 ]. In recent years, engineered recognition elements such as peptides, short chains of amino acids, MIPs, polymer matrices that can be implanted with arbitrary target molecules, and aptamers, short strands of oligonucleotides or peptide domains, have emerged as biorecognition elements due to their high selectivity, specificity, and affinity for their targets, as well as the ability to tailor their structure to a particular target biomarker [ 34 , 43 , 83 , 84 , 86 , 87 , 88 ].…”

“…Several methods of signal transduction have become commonly used for biosensing devices, including optical, electronic, gravimetric, electrochemical, and electromechanical signals [ 43 , 46 , 48 , 79 , 83 , 84 , 85 , 89 , 90 , 91 , 92 , 93 ]. Optical signal transduction methods, which detect signal responses from the binding of biomarkers to biorecognition elements on a surface by measuring changes in refractive index, absorption, or other spectroscopic measurements, have emerged as probably the most common method used in POC diagnostic devices over the past decade [ 46 , 89 , 90 , 91 , 92 , 94 ].…”

Typical Fluorescent Sensors Exploiting Molecularly Imprinted Hydrogels for Environmentally and Medicinally Important Analytes Detection

“…Due to the tight correlation between human health and environmental pollution that results in various diseases, environmental monitoring of pollutants and biomedical diagnosis of biomarkers are global concerns [ 1 , 2 ]. Hence, there is an increasing demand for developing sensors for the selective detection of various targets, such as abused pesticides and overproduced mycotoxins in food samples [ 3 , 4 , 5 , 6 ], as well as biomarkers and tumor cells that represent related diseases [ 7 , 8 , 9 , 10 ].…”