Screen‐printed Electrochemical Immunosensors for the Detection of Cancer and Cardiovascular Biomarkers

Abstract

1Introduction during the last years,S PEs have gone through significant improvements related to both their design and printing materials.S ince cancera nd cardiovascular diseases are the majort hreats of global health, there is ag rowing demand for the development of portable,r apid, simple and inexpensive devices for the detectiono ft hese diseases.T his article presents an overviewa bout the main biomarkers of cancer and cardiovascular diseases and the EIs based on SPEs for the detection of these biomarkers.

Electrochemical Genosensing of Circulating Biomarkers

“…and evaluated as indicators of normal or abnormal processes or conditions or diseases and pharmacologic responses to therapeutics [4]. Concentration levels of these molecules are representative of changes occurring in the basic cell regulatory functions and cellular physiology, such as cell division or contact inhibition, and may vary from their normal levels in case of diseases and disorders [5].…”

“…Circulating biomarkers can derive from various molecular origins, including small molecules such as glucose or cholesterol, DNAs (i.e., specific mutation, translocation, amplification in characteristic genes such as BCRA1 , KRAS , cell-free DNAs, RNAs (mRNAs and miRNAs), proteins (i.e., hormones, antibodies, oncogenes, or tumor suppressors), exosomes and tumor cells. These circulating biomarkers in general can be categorized into different groups according to their potential usage [4,6]: Risk screening biomarkers, used to determine disease susceptibility of an individual,Prognostic biomarkers which provides information on the probability of the disease in an untreated individual,Predictive biomarkers, particular proteins or genes indicating sensitivity or resistance to a specific therapy, andDiagnostic and disease monitoring biomarkers, used to aid the diagnosis and monitoring the progression of disease.…”

“…Other interesting characteristics of SPEs are their versatility of design which allows customizing their production and modification for special applications and multiplexed analysis. Moreover, the planar nature of the SPEs makes easy the modification of their surface, even in a mass-producible way using an automatic dispenser, and their coupling with MBs to develop MBs-based electrochemical genosensors [4]. …”

Multiplexed Electrochemical Immunosensors for Clinical Biomarkers

“…Electrochemical immunosensors constructed with electrode arrays (summarized in Table 1) are commonly fabricated with screen-printed electrodes (SPEs) containing two or more individual elements [60]. SPEs possess advantages derived not only from the good electrical properties, but also from the possibility to be fabricated with different materials and to be drawn in diverse geometries.…”

“…The immunosensing strategy implied the interaction of the respective human antibodies with gliadin and tTG specific antigens immobilized on the nanostructured electrode surface followed by addition of anti-H-IgA-AP or anti-H-IgG-AP, respectively, and a mixture solution of 3-indoxyl phosphate (3-IP) and AgNO 3 . Under these experimental conditions, and as commented above [60], the hydrolysis of 3-IP catalyzed by AP produced an indoxyl intermediate able to provoke silver metal deposition that allowed to develop an anodic stripping method for the sensitive determination of the antibodies [32]. …”