Development of a Fully Differential-Difference Transconductance-Based Filter for Cardiac Troponin Sensor

Abstract

Acute myocardial infarction (AMI) is one of the foremost global health threats. Human cardiac troponin I (cTnI) is an effective and golden biomarker for accurately diagnosing AMI. Owing to higher fatality worldwide, an accurate, rapid diagnosis of AMI is highly significant at the early stage for effective treatment. This study designed a novel portable cardiac troponin sensor using a fully differential-difference transconductance-based fifth-order double-notch low pass filter (FDdiff_5thDNLPF) for accurate and early diagnosis of AMI by identifying cTnI. The developed biosensor system can identify cTnI from the blood samples. The twofold ion-sensitive gated field effect transistor (TISG-FET), which can provide a dynamic range, high sensitivity, and high selectivity to target analyte, is used to identify cTnI level and transform the cTnI concentration to drain the current signal. The differential-input instrumentation amplifier (DiffInp_IA) is used as a preamplifier to receive and amplify the input current. The FDdiff_5thDNLPF circuit removes unwanted noises and eliminates available frequencies greater than 50[Formula: see text]Hz powerline interference. The signals are then provided to an intermediate amplifier and converted to digital form using an analog-to-digital converter (ADC) circuit. Further, the digital signals have been processed through a central processing unit (CPU), and the data can be displayed. The proposed system for cTnI detection is simulated on the cadence Virtuoso tool. As a result, the proposed system exhibited a minimum detection limit of 0.31[Formula: see text]pg/ml, a wide linear range among 1–1000[Formula: see text]pg/ml and higher sensitivity of 131[Formula: see text]pA[Formula: see text]pg[Formula: see text][Formula: see text]ml[Formula: see text].