Recent Developments in Aptasensors for Diagnostic Applications

Abstract

Aptamers are exciting smart molecular probes for specific recognition of disease biomarkers. A number of strategies have been developed to convert target−aptamer binding into physically detectable signals. Since the aptamer sequence was first discovered, a large variety of aptamer-based biosensors have been developed, with considerable attention paid to their potential applications in clinical diagnostics. So far, a variety of techniques in combination with a wide range of functional nanomaterials have been used for the design of aptasensors to further improve the sensitivity and detection limit of target determination. In this paper, the advantages of aptamers over traditional antibodies as the molecular recognition components in biosensors for high-throughput screening target molecules are highlighted. Aptamer−target pairing configurations are predominantly single-or dual-site binding; the design of recognition modes of each aptamer−target pairing configuration is described. Furthermore, signal transduction strategies including optical, electrical, mechanical, and masssensitive modes are clearly explained together with examples. Finally, we summarize the recent progress in the development of aptamer-based biosensors for clinical diagnosis, including detection of cancer and disease biomarkers and in vivo molecular imaging. We then conclude with a discussion on the advanced development and challenges of aptasensors.

Paper-based analytical devices for virus detection: Recent strategies for current and future pandemics

“…RNA aptamers are degraded by nuclease activity of RNases, which makes it difficult to develop antiviral aptamers. Since full-length membrane protein purification of viral particles is challenging, Cell-SELEX (systematic evolution of ligands by exponential enrichment), which uses whole cells instead of target proteins, has been developed to selectively bind to the target [ 188 ]. In a recent study, Liu et al demonstrated a LFA based on magnetic enrichment and SDA to detect coat protein of red-spotted grouper nervous necrosis virus (RGNNV-CP) [ 189 ].…”

Advances in Optical Aptasensors for Early Detection and Diagnosis of Various Cancer Types

“…There are many challenges if the aptasensor based sensing platform is to be used commercially. For example, improved signal-to-noise ratio and a high level of confidence in signal detection must be recognized ( 74 ). The compatibility of aptasensor assay with current equipment of diagnostics units is also an issue and is for the reason of the fragility of aptasensors ( 75 ).…”

“…The cost of the whole sensing system should also be considered, for example, the cost of TCM components (laser) is expensive and uses a bulky femtosecond laser setup ( 11 ). Aptasensors after resolving all the above-discussed obstacles can be one of the most important early cancer detection tools ( 74 ).…”

Mof@Mos2-Based Electrochemical Biosensor for Ca125 Detection

“…After selection and characterization, aptamers can be customized for developing sensors [18]. A large variety of aptamer-based biosensors (aptasensors) with various detection strategies have been developed and reported in the literature [19].…”