Multimodal technique to eliminate humidity interference for specific detection of ethanol

Traditionally, electrochemical procedures aimed at determining substance concentrations have required a costly and cumbersome laboratory environment. Specialized equipment and personnel obtain precise results under complex and time-consuming settings. Innovative electrochemical-based sensors are emerging to alleviate this difficulty. However, they are generally scarce, proprietary hardware and/or software, and focused only on measuring a restricted range of substances. In this paper, we propose a portable, flexible, low-cost system, built from commercial off-the-shelf components and easily controlled, using open-source software. The system is completed with a wireless module, which enables the transmission of measurements to a remote database for their later processing. A well-known PGSTAT100 Autolab device is employed to validate the effectiveness of our proposal. To this end, we select ascorbic acid as the substance under consideration, evaluating the reliability figure and obtaining the calibration curves for both platforms. The final outcomes are shown to be feasible, accurate, and repeatable.

Section: Introductionmentioning

confidence: 99%

A COTS-Based Portable System to Conduct Accurate Substance Concentration Measurements

Aznar-Poveda

López-Pastor

Otero

2018

“…Further digital smoothing of the data, such as with a Savitzky-Golay filter, could improve our calculations and lower our percent error. Despite this error, we observed better agreement with a commercial potentiostat than others using the LMP91000 have reported [14,22,25] and are able to run more advanced electrochemical techniques, such as SWV and NPV, instead of CV alone.…”

Section: Potassium Ferricyanidementioning

confidence: 47%

“…Such aptamer-based biosensors require pulse voltammetry techniques like square wave voltammetry (SWV) [13] to obtain the necessary sensitivity to accurately quantify the signal produced by the aptamer upon binding to the analyte. 2 of 12 Due to the growing popularity of electrochemical biosensors, numerous in-house potentiostats have been presented in the literature [9,[14][15][16][17][18][19][20][21][22][23][24][25][26][27]. Such designs aim to decrease the cost and increase the accessibility of potentiostats with the goal of democratizing scientific research or to miniaturize electrochemistry hardware for use in at-home or portable diagnostic devices.…”

Section: Introductionmentioning

confidence: 99%

“…The LMP91000's integrated features allow for basic electrochemical techniques such as cyclic voltammetry (CV) and chronoamperometry (CA) used in lactate and glucose sensors, but lack sufficient voltage reference generators to perform more complex voltammetric techniques like SWV and normal pulsed voltammetry (NPV). Some designs have leveraged the LMP91000 [7,14,[22][23][24][25][26]31,32], but have limited voltage reference generators and limited, if any, on-chip signal-processing capabilities.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

KickStat: A Coin-Sized Potentiostat for High-Resolution Electrochemical Analysis

Hoilett

Walker

Balash

et al. 2020

The demand for wearable and point-of-care devices has led to an increase in electrochemical sensor development to measure an ever-increasing array of biological molecules. In order to move from the benchtop to truly portable devices, the development of new biosensors requires miniaturized instrumentation capable of making highly sensitive amperometric measurements. To meet this demand, we have developed KickStat, a miniaturized potentiostat that combines the small size of the integrated Texas Instruments LMP91000 potentiostat chip (Texas Instruments, Dallas, TX, USA) with the processing power of the ARM Cortex-M0+ SAMD21 microcontroller (Microchip Technology, Chandler, AZ, USA) on a custom-designed 21.6 mm by 20.3 mm circuit board. By incorporating onboard signal processing via the SAMD21, we achieve 1 mV voltage increment resolution and an instrumental limit of detection of 4.5 nA in a coin-sized form factor. This elegant engineering solution allows for high-resolution electrochemical analysis without requiring extensive circuitry. We measured the faradaic current of an anti-cocaine aptamer using cyclic voltammetry and square wave voltammetry and demonstrated that KickStat's response was within 0.6% of a high-end benchtop potentiostat. To further support others in electrochemical biosensors development, we have made KickStat's design and firmware available in an online GitHub repository.

“…Breath humidity is important for detection of hydration, and for accurately detecting other parameters related to metabolism [10], lung function [11], and renal status [12]. Scaling breath sensing technologies to clinical and consumer levels, however, is a massive challenge due to complexities in handling breath [13,14,15,16]. Breathing involves inconsistent and complex flow patterns and sampling involves massive changes in both humidity and temperature, especially in rebreathing applications.…”

Section: Introductionmentioning

confidence: 99%

Thermochemical Humidity Detection in Harsh or Non-Steady Environments

Bridgeman

Tsow

Xian

et al. 2017

We present a new method of chemical quantification utilizing thermal analysis for the detection of relative humidity. By measuring the temperature change of a hydrophilically-modified temperature sensing element vs. a hydrophobically-modified reference element, the total heat from chemical interactions in the sensing element can be measured and used to calculate a change in relative humidity. We have probed the concept by assuming constant temperature streams, and having constant reference humidity (~0% in this case). The concept has been probed with the two methods presented here: (1) a thermistor-based method and (2) a thermographic method. For the first method, a hydrophilically-modified thermistor was used, and a detection range of 0–75% relative humidity was demonstrated. For the second method, a hydrophilically-modified disposable surface (sensing element) and thermal camera were used, and thermal signatures for different relative humidity were demonstrated. These new methods offer opportunities in either chemically harsh environments or in rapidly changing environments. For sensing humidity in a chemically harsh environment, a hydrophilically-modified thermistor can provide a sensing method, eliminating the exposure of metallic contacts, which can be easily corroded by the environment. On the other hand, the thermographic method can be applied with a disposable non-contact sensing element, which is a low-cost upkeep option in environments where damage or fouling is inevitable. In addition, for environments that are rapidly changing, the thermographic method could potentially provide a very rapid humidity measurement as the chemical interactions are rapid and their changes are easily quantified.