The reverse transcription-quantitative polymerase chain reaction (RT-qPCR) approach has been widely used to detect the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, instead of using it alone, clinicians often prefer diagnose disease 2019 (COVID-19) by utilizing a combination clinical signs and symptoms, laboratory test, imaging measurement (e.g., chest computed tomography scan), multivariable prediction models, including electronic nose. Here, we report on...

Authentication of meat floss origin has been highly critical for its consumers due to existing potential risks having allergic diseases or religion perspective related pork-containing foods. Herein, we developed and assessed a compact portable electronic nose (e-nose) comprising gas sensor array supervised machine learning with window time slicing method sniff classify different products. We evaluated four methods data classification (i.e., linear discriminant analysis (LDA), quadratic...

This study introduced a metal-oxide-semiconductor (MOS) based electronic nose (E-nose) to perform on-the-spot classification of superior-quality black tea. A piecewise feature method on line-fitting model was extract comprehensive features E-nose sensor response curves. Principal component analysis (PCA) and linear discriminant (LDA) were used for data dimensionality reduction structure visualization. Support vector machine (SVM) with Radial kernel function assess the performance E-nose. The...

We devised a low-cost mobile electronic nose (e-nose) system using quartz crystal microbalance (QCM) sensor array functionalized with various polymer-based thin active films (i.e., polyacrylonitrile, poly(vinylidene fluoride), poly(vinyl pyrrolidone), and acetate)). It works based on the gravimetric detection principle, where additional mass of adsorbed molecules polymer surface can induce QCM resonance frequency shifts. To collect process obtained sensing data sets, multichannel acquisition...

Short-chain alcohols are a group of volatile organic compounds (VOCs) that often found in workplaces and laboratories, as well medical, pharmaceutical, food industries. Real-time monitoring alcohol vapors is essential because exposure to with concentrations 0.15–0.30 mg·L−1 may be harmful human health. This study aims improve the detection capabilities quartz crystal microbalance (QCM)-based sensors for analysis vapors. The active layer chitosan was immobilized onto QCM substrate through...

An electronic nose (E-nose), comprising eight metal oxide semiconductor (MOS) gas sensors, was used in situ for real-time classification of black tea according to its quality level. Principal component analysis (PCA) coupled with signal preprocessing techniques (i.e., time set value preprocessing, F1; area under curve F2; and maximum F3), allowed grouping the samples from seven brands The E-nose performance further checked using multivariate supervised statistical methods, namely, linear...

Safrole is the main precursor for producing amphetamine-type stimulant (ATS) drug,

Abstract. Quartz crystal microbalance (QCM) coated with poly(3,4-ethylenedioxythiophene) and polystyrene sulfonate mixed polyvinyl alcohol (PEDOT–PSS/PVA) nanofiber has been fabricated as a humidity sensor using the electrospinning method. Three types of PEDOT–PSS/PVA sensors are different needle-to-collector distances. The scanning electron microscope images confirm presence beads in structure. results show that mass deposition increased decrease distance. best performance is exhibited by...

A portable electronic nose (e-nose) using low-cost dynamic headspace and commercially metal oxide gas sensors has been developed. This paper reports evaluation on the performance of e-nose to classify vegetable oils (sunflower grape seed oils) animal fats (mutton, chicken pig fats). The consists a sampling, sensor array real-time data acquisition system based ATMega-16 microcontroller. can divided into two chambers, i.e. sample room. It is also equipped with three small fans for adjusting...

Background Even though conceptually, Tuberculosis (TB) is almost always curable, it currently the world’s leading infectious killer. Patients with pulmonary TB are source of transmission. Approximately 23% population believed to be latently infected bacteria, and 5–15% them will progress at any point in time develop disease. There was a global diagnostic gap 2.9 million between notifications new cases estimated number incident cases, Indonesia carries third-highest this gap. Therefore,...

Fabrication of quartz crystal microbalance (QCM) based humidity sensor has been carried out by electrospinning polyacrylonitrile (PAN) nanofiber followed with deposition poly (3,4-ethylenedioxythiophene): polystyrene sulfonate (PEDOT:PSS) on the QCM surface. The PAN nanofibers were deposited using technique and PEDOT:PSS drop dip coating technique. After dried, sensors tested various relative values ranging from 38% to 59% at a constant room temperature. As result, sensitivity was showed in...

Tempeh is a traditional Indonesian food made from fermented soybeans using Rhizopus sp. has large opportunity in the global industrial scale, so monitoring production process of tempeh needed. In this paper, electronic nose used to study fermentation and stages linear discriminant analysis (LDA) method. The results LDA show that there are six tempeh. stage-1 stageS fungus growth, while stage-6 decay. classified four classification methods: LDA, support vector machine (SVM), k-nearest...

Tempeh is a popular traditional food from Indonesia, and its physical chemical characteristics have been intensively investigated. Study on the fermentation process, however, still requires more attention. Here, aroma profile during 10-day process was analyzed using an electronic nose (e-nose). The e-nose used in this study based eight kinds of gas sensor (metal oxide semiconductor). A differential baseline manipulation maximum value as feature extraction were applied for data processing....

Polyacrylonitrile (PAN) nanofiber deposited on quartz crystal microbalance (QCM) substrate as solvent vapor sensing has been successfully developed. The absorption and swelling behavior assumed to be responsible for mechanism in sensing. In this study, we aim investigate the correlation between degree (polymer-solvent affinity) sensor response. PAN QCM with relatively homogenous diameter about (260 ± 20) nm. tests was included dimethylformamide (DMF), dimethylacetamide (DMAc), ethylene...

An electronic nose (E-nose), comprising eight metal oxide semiconductor (MOS) gas sensors and a moisture-temperature sensor, was used for classifying three quality grades of superior java cocoa beans, namely fine dark bean < 20%, > 60%, bulk that is harder task compared to the discrimination high versus low-quality beans.The E-nose signals were pre-processed using maximum value method.The capability discriminating grade beans checked by applying multivariate statistical tools, namely, linear...

Here, we describe an N,N-dimethyl formamide (DMF) vapour sensor fabricated by coating polyacrylonitrile (PAN) nanofiber structured on quartz crystal microbalance (QCM). The PAN sensors with average diameter of 225 nm to 310 were via electrospinning process different mass deposition QCM substrate. nanostructured offers a high specific surface area that improved the sensing performance sensors. Benefiting from fine structure, and polymer-solvent affinity between DMF, development DMF presented...

Here, we propose a simple yet effective method to predict gas sensor sensitivity based on solubility and vapor pressure. As sensing devices for the case study, employed quartz crystal microbalance sensors coated with polyvinyl acetate (PVAc) nanofibers. The was represented by relative energy density (RED), while pressure expressed logarithm of (log P). To create prediction model, chemometric technique involving machine learning algorithm k-nearest neighbor (KNN) regression used in analysis....

Abstract Despite its high accuracy to detect the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), reverse transcription-quantitative polymerase chain reaction (RT-qPCR) approach possesses several limitations (e.g., lengthy invasive procedure, reagent availability, and requirement of specialized laboratory, equipment, trained staffs). We developed employed a low-cost, noninvasive method rapidly sniff out disease 2019 (COVID-19) based on portable electronic nose (GeNose C19)...

In many cases, acetic acid is categorized as hazardous to health. A high-performance sensor for detecting urgently required. This study aims observe the characteristics of quartz crystal microbalance (QCM) coated with polyacrylamide an sensor. For this purpose, we prepared by firstly coating 1-dodecanethiol (using self-assembled-monolayers or SAM technique) followed subsequently glutaraldehyde and (PAM).As results, sensors showed less sensitivity humidity changes, which one basic...

Feature extraction of electronic nose (e-nose) output response aims to reduce information redundancy so that the e-nose performance can be improved. The use different sensor types and sample targets affect optimization feature extraction. This research used six metal oxide sensors, TGS 813, 822, 825, 826, 2620, 2611 in an system detect three herbal drink. Five kinds methods on original curve a steady-state were used, namely, baseline difference, logarithmic local normalization, global...