Label-Free Biosensors for Laboratory-Based Diagnostics of Infections: Current Achievements and New Trends

Abstract

Infections pose a serious global public health problem and are a major cause of premature mortality worldwide. One of the most challenging objectives faced by modern medicine is timely and accurate laboratory-based diagnostics of infectious diseases. Being a key factor of timely initiation and success of treatment, it may potentially provide reduction in incidence of a disease, as well as prevent outbreak and spread of dangerous epidemics. The traditional methods of laboratory-based diagnostics of infectious diseases are quite time- and labor-consuming, require expensive equipment and qualified personnel, which restricts their use in case of limited resources. Over the past six decades, diagnostic technologies based on lateral flow immunoassay (LFIA) have been and remain true alternatives to modern laboratory analyzers and have been successfully used to quickly detect molecular ligands in biosubstrates to diagnose many infectious diseases and septic conditions. These devices are considered as simplified formats of modern biosensors. Recent advances in the development of label-free biosensor technologies have made them promising diagnostic tools that combine rapid pathogen indication, simplicity, user-friendliness, operational efficiency, accuracy, and cost effectiveness, with a trend towards creation of portable platforms. These qualities exceed the generally accepted standards of microbiological and immunological diagnostics and open up a broad range of applications of these analytical systems in clinical practice immediately at the site of medical care (point-of-care concept, POC). A great variety of modern nanoarchitectonics of biosensors are based on the use of a broad range of analytical and constructive strategies and identification of various regulatory and functional molecular markers associated with infectious bacterial pathogens. Resolution of the existing biosensing issues will provide rapid development of diagnostic biotechnologies.

A Self-Powered Biosensor for Monitoring Maximal Lactate Steady State in Sport Training

“…The target solution (0.5 mL) was dropped on the test device, and the device is driven by the programmable measurement system (45°). Generated the piezoelectric voltage signal (Both as a power source and as a biosensor signal) through the piezoelectric surface coupling effect, the piezoelectric voltage signal can act as both a power source and a biosensor signal [ 43 , 44 , 45 ]. Figure 4 a shows that the outputting piezoelectric voltage of the device decreases with the increasing in the lactate concentration.…”

Demonstration of a Label-Free and Low-Cost Optical Cavity-Based Biosensor Using Streptavidin and C-Reactive Protein

“…The early diagnosis of diseases, including cancers, infectious diseases, and cardiovascular diseases, is vital in order to apply effective treatments and increase the chance of full recovery [ 1 , 2 , 3 , 4 ]. Diagnostic technologies in the current healthcare system are mostly used at centralized laboratories, involve costly and time-consuming processes, and are operated by expert staff [ 2 , 5 , 6 ]. For example, enzyme-linked immunosorbent assay (ELISA), considered as the gold standard diagnostic method, is labor-intensive, requiring complicated procedures such as labeling and multiple washing steps [ 2 , 5 , 7 , 8 ].…”

“…With these limitations in the current diagnostic technologies, it is difficult for people to monitor their health status regularly, which would eventually increase the chance of being diagnosed with diseases at late stages [ 3 , 7 ]. The problems become worse for people who are in financial difficulties and living in developing countries with deficient healthcare systems [ 6 , 13 ]. To address these challenges existing in the conventional diagnostic field, a point-of-care (POC) biosensor has emerged as a promising alternative, allowing patients to regularly check their health condition at the bedside or near them without being dependent on central laboratory testing [ 4 , 6 , 14 , 15 , 16 , 17 ].…”

“…The problems become worse for people who are in financial difficulties and living in developing countries with deficient healthcare systems [ 6 , 13 ]. To address these challenges existing in the conventional diagnostic field, a point-of-care (POC) biosensor has emerged as a promising alternative, allowing patients to regularly check their health condition at the bedside or near them without being dependent on central laboratory testing [ 4 , 6 , 14 , 15 , 16 , 17 ]. According to the World Health Organization, an ideal POC test should satisfy the ASSURED (affordable, sensitive, specific, user-friendly, rapid, equipment-free, deliverable to end-users) criteria [ 16 , 17 ].…”

“…According to the World Health Organization, an ideal POC test should satisfy the ASSURED (affordable, sensitive, specific, user-friendly, rapid, equipment-free, deliverable to end-users) criteria [ 16 , 17 ]. One of the most widely available and commercialized POC devices is based on lateral flow assays (LFAs) with their low cost, ease of use, and speed [ 4 , 6 , 18 ]. However, limitations still remain with regard to LFAs in terms of producing reproducible and sensitive test results [ 6 , 18 , 19 ].…”