Aptamers Targeting Membrane Proteins for Sensor and Diagnostic Applications

Abstract

Many biological processes (physiological or pathological) are relevant to membrane proteins (MPs), which account for almost 30% of the total of human proteins. As such, MPs can serve as predictive molecular biomarkers for disease diagnosis and prognosis. Indeed, cell surface MPs are an important class of attractive targets of the currently prescribed therapeutic drugs and diagnostic molecules used in disease detection. The oligonucleotides known as aptamers can be selected against a particular target with high affinity and selectivity by iterative rounds of in vitro library evolution, known as Systematic Evolution of Ligands by EXponential Enrichment (SELEX). As an alternative to antibodies, aptamers offer unique features like thermal stability, low-cost, reuse, ease of chemical modification, and compatibility with various detection techniques. Particularly, immobilized-aptamer sensing platforms have been under investigation for diagnostics and have demonstrated significant value compared to other analytical techniques. These “aptasensors” can be classified into several types based on their working principle, which are commonly electrochemical, optical, or mass-sensitive. In this review, we review the studies on aptamer-based MP-sensing technologies for diagnostic applications and have included new methodological variations undertaken in recent years.

Aptamer-Based Imaging of Polyisoprenoids in the Malaria Parasite

“…Compared to non-membrane molecular targets, the successful selection of aptamers for membrane molecular targets has been relatively limited [ 17 ]. Notably, in the case of membrane proteins, various selection methods have been employed, including the use of soluble protein fragments, detergent–membrane protein mixed micelles, whole cells, vesicles derived from cellular membranes, and enveloped viruses [ 18 ]. For targeting membrane lipids, liposomes have served as an experimental system for aptamer selection [ 17 ].…”

Strategies for targeted gene delivery using lipid nanoparticles and cell-derived nanovesicles

“…Aptamers are single-stranded RNA or DNA molecules that can bind to specific proteins, similar to antibodies. 163,164 Aptamers can effectively bind to the target protein only when both of them maintain their tertiary structure, and the isolated CDNs can easily be seperated by adjusting the ionic strength and metal ion concentration to cleave the bonding between aptamers and CDNs. 165,166 Zhang et al utilized a DNA aptamer immobilized matrix for isolating CDNs having the MUC1 protein.…”

“…Also, CDNs are isolated in various ways including ultracentrifugation, filtration, immunoaffinity, polymer precipitation, and stimuli techniques. 134–181 According to the references we mentioned, various combinations of the isolation method and targeting strategy of CDNs exist. Not only is it important to decide whether to use LNPs or CDNs to target specific cells, but it is also important to carefully determine what each individual strategy is.…”

Electrospun nanofibers synthesis enhancing the activity of energy storage devices/electrochemical and biosensor applications

“…Additionally, there were two aligned optical fibers, each possessing a coating of 40 nm high-reflection gold film on their end facets. This coating facilitated the creation of an FP cavity with a gap measuring 35.5 m. The reflecting characteristics of the system will result in the reflection of the incident light within the Fabry-Perot cavity, causing it to oscillate back and forth [269]. The resulting light would manifest as multi-beam interference, giving rise to the interference spectrum.…”