A Self-Calibrating IoT Portable Electrochemical Immunosensor for Serum Human Epididymis Protein 4 as a Tumor Biomarker for Ovarian Cancer

Abstract

Nowadays, analytical techniques are moving towards the development of smart biosensing strategies for the point-of-care accurate screening of disease biomarkers, such as human epididymis protein 4 (HE4), a recently discovered serum marker for early ovarian cancer diagnosis. In this context, the present work represents the first implementation of a competitive enzyme-labelled magneto-immunoassay exploiting a homemade IoT Wi-Fi cloud-based portable potentiostat for differential pulse voltammetry readout. The electrochemical device was specifically designed to be capable of autonomous calibration and data processing, switching between calibration, and measurement modes: in particular, firstly, a baseline estimation algorithm is applied for correct peak computation, then calibration function is built by interpolating data with a four-parameter logistic function. The calibration function parameters are stored on the cloud for inverse prediction to determine the concentration of unknown samples. Interpolation function calibration and concentration evaluation are performed directly on-board, thus reducing the power consumption. The analytical device was validated in human serum, demonstrating good sensing performance for analysis of HE4 with detection and quantitation limits in human serum of 3.5 and 29.2 pM, respectively, reaching the sensitivity that is required for diagnostic purposes, with high potential for applications as portable and smart diagnostic tool for point-of-care testing.

Emerging point-of-care biosensors for rapid diagnosis of COVID-19: current progress, challenges, and future prospects

“…Chip-based biosensors are one of the POC biosensors used for POC diagnosis of many infectious diseases. They are prepared either by miniaturizing conventional biochemical assays on a microchip scale [ 70 , 71 ] or by integrating novel detection principles with microfluidic chips [ 72 , 73 ]. These biosensors are mainly made of polymethyl methacrylate (PMMA), polytetrafluoroethylene (PTEE), or polydimethylsiloxane (PDMS) [ 74 , 75 ].…”

IoT and Biosensors: A Smart Portable Potentiostat With Advanced Cloud-Enabled Features

“…In [28], a Wi-Fi potentiostat based on LMP91000 hardware, which allows only semi-quantitative analyses, is presented. In [15], [29], a Wi-Fi solution used to transfer analyses results to the cloud is proposed. In this case, the developed hardware exhibits a limited versatility since the reading range is fixed, i.e.…”

NB-IoT and Wi-Fi Technologies: An Integrated Approach to Enhance Portability of Smart Sensors

“…The transmission measurements were carried out with a payload size from 4 to 500 bytes for both Wi-Fi and NB-IoT transceivers. Data words of 4 and 16 bytes are suitable for WSs aimed at disease diagnostic [21]. In Fig.…”

“…Indeed, a typical example, where the allowed data size is easily saturated, is the three-axis accelerometer and gyroscope sending one data word per minute. Moreover, the downlink limitation is critical in those applications requiring access to data that have been previously stored in a cloud space (e.g., calibration data of portable sensors for disease diagnostic [21]).…”