Simulating the Effects of Skin Thickness and Fingerprints to Highlight Problems With Non-Invasive RF Blood Glucose Sensing From Fingertips

Abstract

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Radio-Frequency and Microwave Techniques for Non-Invasive Measurement of Blood Glucose Levels

“…The decrease in resonance is 1.7% and 0.8% for an increase in applied force from 1 V to 1.5 V and from 1.5 V to 2 V, respectively. This could be due to the tissue displacement: it is hypothesized that the fat tissue is displaced with the increase in applied force (also suggested recently in the literature [42,62]). This experiment was important to assess the effect of the applied force to the resonator.…”

“…In addition to this, it has been shown that non-invasive blood glucose sensing at finger-tips is affected by layer thickness and even the presence of small air-gaps caused by finger-prints [41,42]. A shift in resonant frequency of around 20 MHz was observed due to these air-gaps [41] and potentially as much as 100 MHz, depending on fingerprint depth [42].…”

“…In addition to this, it has been shown that non-invasive blood glucose sensing at finger-tips is affected by layer thickness and even the presence of small air-gaps caused by finger-prints [41,42]. A shift in resonant frequency of around 20 MHz was observed due to these air-gaps [41] and potentially as much as 100 MHz, depending on fingerprint depth [42]. Given that the air-gaps will differ depending on how the finger is placed on the sensor [41,42], in addition to the effect of pressure on the tissues in the finger tip, it is clear that this effect must be carefully considered, given that frequency shifts as low as 8 MHz [43] could be produced by changes in glucose concentrations, at least for resonators with relatively low Q-factors.…”

Non Invasive Measurement of Hemoglobin using Optical Sensor

“…The objective of this examination was to decide the accuracy of the petMAP in anesthetized sheep confronting a medical procedure [2].Machine learning techniques and characteristic features of the photo plethysmography signals are utilized for the measurement of hemoglobin non-invasively [3].A noninvasive antenatal finding of hb Bart's disease by cardiothoracic ratio over the first period was given [4].The effects of a sympathetic block on Plethysmographic analysis of Hb concentration, Perfusion and Pleth variability Index with the Radical-7 apparatus was studied [5].The hb concentration in arterial blood was measured non-invasively. For this purpose a magnet was used which is set essentially over the radial artery of an individual whose hb concentration is to be discovered [6].Observable Red Laser light of wavelength 650 nm was used by the simple and beneficial noninvasive device for Blood Glucose Monitoring (RL-BGM) [7].The impacts of Skin thickness and Fingerprints was pretended to show the issues with Noninvasive RF Blood Glucose Sensing from Fingertips [8]. The Pulse Waves (PW) are portrayed non obtrusively from the upper and lower extremity from 52 healthy volunteers without known cardiovascular ailments [9].Dynamic Spectrum analysis is utilized for the estimation of hemoglobin concentration non obtrusively [10].…”

Design of an ELC resonator-based reusable RF microfluidic sensor for blood glucose estimation

“…Non-invasive methods involve blood glucose estimation from the fingertips or earlobes using patch resonator, spiral microstrip resonator, ultra-wideband antenna, bandpass filter or spatially separated split ring resonators 11 – 15 . Even though non-invasive methods appear promising and convenient, they are associated with high degrees of unpredictability due to the variations in the skin thickness, applied pressure and fingerprints 16 , 17 . Invasive methods are, therefore, the more popular means of blood glucose monitoring at microwave frequencies.…”