A Simple and Low‐Cost Electrochemical Immunosensor for Ultrasensitive Determination of Calreticulin Biomarker in Human Serum

Abstract

An early on time detection of breast cancer significantly affects the treatment process and outcome. Herein, a new label‐free impedimetric biosensor is developed to determine the lowest change in the level of calreticulin (CALR), which is a new biomarker of breast carcinoma. The proposed immunosensor is fabricated by using reduced graphene oxide/amino substituted polypyrrole polymer (rGO‐PPyNH2) nanocomposite modified disposable electrode. The anti‐CALR antibodies are first attached on the rGO‐PPyNH2 nanocomposite coated electrode through glutaraldehyde crosslinking; the CALR antigens are then immobilized with the addition of CALR antigens to form an immunocomplex on the sensing surface. This immunocomplex induces considerably larger interfacial electron transport resistance (Rct). The variation in the Rct has a linear relationship with CALR level in the detection range of 0.025 to 75 pg mL−1, with a detection limit of 10.4 fg mL−1. The suggested biosensor shows high selectivity to CALR, good storage stability (at least 5 weeks) and suitable reproducibility results as shown in quality control chart. The designed immunosensor is utilized to analyze CALR levels in human sera with satisfying results. This immunosensor provides a novel way for the clinical determination of CALR and other cancer biological markers.

Electrochemical Behavior of Janus Kinase Inhibitor Ruxolitinib at a Taurine-Electropolymerized Carbon Paste Electrode: Insights into Sensing Mechanisms

“…Nyquist plots typically exhibit two regions along the axis: the first region portrays a semicircular shape, while the second region manifests as a straight line. The semicircular segment observed at high frequencies corresponds to the process governed by electron transfer, whereas the linear portion observed at low frequencies represents the process controlled by diffusion. − Figure shows the EIS spectra of both bare CP and poly­(taurine)-CP electrodes in the frequency range of 0.01 to 10,000 Hz in 0.5 M KCl/2.0 mM [Fe­(CN) 6 ] 3–/4– redox probe solution. It was observed that the largest semicircle diameter was obtained on the CP electrode.…”

Thymoquinone, a Novel Multi-Strike Inhibitor of Pro-Tumorigenic Breast Cancer (BC) Markers: CALR, NLRP3 Pathway and sPD-L1 in PBMCs of HR+ and TNBC Patients

“…Plant-derived agents such as vincristine and paclitaxel are among the most effective cancer chemotherapeutics [ 110 ]. Interestingly, various chemotherapeutics led to the secretion of danger signals [ 111 ] such as CALR [ 16 ] which showed various tumor-promoting effects in BC and has been recently addressed as a biological marker of BC [ 28 , 29 , 30 , 31 , 32 , 33 , 34 ]. CALR has been reported to be an activator to the NLRP3 pathway [ 36 , 37 , 38 , 39 ].…”

“…Interestingly, the exposed CALR has been shown to be subsequently released and detected in the extracellular milieu [ 27 ]. Recently, CALR has been addressed as a promising biological marker of BC and an indicator of BC staging and prognosis [ 28 , 29 , 30 , 31 , 32 ]. In addition, the literature reported that CALR expression was associated with more advanced tumors in a study of 228 BC samples [ 33 ].…”

Recent Progress in Biomedical Sensors Based on Conducting Polymer Hydrogels

“… 62 The resulting nanoimmunosensor could differentiate between the SSc-related biomarkers from different sets of patients with a limit of detection (LOD) of 0.42 pg mL –1 , which is better than that of the gold standard, ELISA, and gave reproducible results with less than 4% of deviation. Similarly, the group of Aydin et al 201 also fabricated an immunsensor based on reduced graphene oxide/amino-substituted PPy for the detection of calreticulin (CALR), a novel biomarker for breast cancer, via EIS measurements. The resulting sensor exhibited a wide detection range from 0.025 to 75 pg mL –1 , good selectivity in the presence of interferences, a good storage stability, and a LOD of 10.4 fg mL –1 .…”