Aptamer-Assisted Protein Orientation on Silver Magnetic Nanoparticles: Application to Sensitive Leukocyte Cell-Derived Chemotaxin 2 Surface Plasmon Resonance Sensors

Abstract

Leukocyte cell-derived chemotaxin 2 (LECT2) has been proved to be a potential biomarker for the diagnosis of liver fibrosis. In this work, a sensitive surface plasmon resonance (SPR) assay for LECT2 analysis was developed. Tyrosine kinase with immune globulin-like and epidermal growth factor-like domains 1 (Tie1) is an orphan receptor of LECT2 with a C-terminal Fc tag, which is far away from the LECT2 binding sites. The Fc aptamer was intentionally used to capture the Tie1 through its Fc tag, connecting with Fe3O4-coated silver magnetic nanoparticles (Ag@MNPs) and ensuring the LECT2 binding site to be outward. Attributed to the orientation nature of the captured protein, Ag@MNPs were able to enhance the SPR signal. A sensitive LECT2 sensor was successfully fabricated with a detection limit of 10.93 pg/mL. The results showed that the immobilization method improved the binding efficiency of Tie1 protein. This strategy could be extended to attach antibodies or recombinant Fc label proteins to Fc aptamer-based nanoparticles.

Electrochemical Aptamer-Based Sensors with Tunable Detection Range

“…Besides the density, the probe orientation and arrangement could also affect the detection performance of the E-AB sensors . Furthermore, they can be controlled by pretreatment of the sensors.…”

An Overview of the Synergy of Electrochemistry and Nanotechnology for Advancements in Sensing Applications

“…In the recent times, the utility of MNPs has increased multifold. Some advanced sensing applications of MNPs are as follows: diagnosis of anticancer drug 6-mercaptopurine using cerium-based MNP as a fast-response and efficient fluorescence quenching sensor [59], Ihlamur leaves [60] and saffron flowers [61]-based biosynthesis of magnetic nanoparticles for antibacterial applications, use of silver MNPs to enhance the surface plasmon resonance signal for determination of leukocyte cell-derived chemotaxin-2 which is an important biomarker for the diagnosis of liver fibrosis [62], green synthesis of Fe 3 O 4 nanoflakes and its utility as an electrocatalyst for the voltammetric determination of ascorbic acid [63], diversified biomedical applications of multifunctional MNPs [64], and many more.…”

Review of Interface Modification Based on 2D Nanomaterials for Surface Plasmon Resonance Biosensors

“…A considerable amount of research has focused on the use of the coupling effect between the unique local surface plasmon resonance (LSPR) of noble metal nanoparticles and the surface plasmon wave of the metal film on the SPR sensor surface to achieve greater electric field enhancement. − On the other hand, surface-biofunctionalized magnetic nanoparticles can not only achieve pre-enrichment of target analytes but also significantly improve the refractive index on the chip surface . Therefore, the SPR enhancement strategy based on noble metals and magnetic nanoparticles has significant advantages over the traditional double-antibody sandwich method. , The above involves different signal enhancement mechanisms: (1) Nanoparticles attached to the target can effectively increase the refractive index near the interface, resulting in greater signal output. − (2) The coupling effect between the unique LSPR of noble metal nanoparticles and the propagating surface plasmon resonance (PSPR) of the metal film will generate a stronger localized electric field. − (3) By introducing graphene-based nanomaterials on the surface of the SPR chip, the binding capacity of biomarkers on the chip can be improved through the strong π stacking force. In addition, the separation and pre-enrichment of targets by magnetic nanomaterials can significantly improve the perception of low-concentration analytes’ force. − (4) The size of nanoparticles and gap size between the nanoparticle and sensor film significantly affect the strength and penetration depth of the evanescent field (from tens of nanometers to hundreds of nanometers).…”