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91	Sensor	ABS-24
Electrospun Tin Dioxide (SnO2) Nanofiber as an Active Layer of Acetone Sensors based-on Quartz Crystal Microbalance Technique Aditya Rianjanu 1,2,a, Kurniawan D. P. Marpaung 1, Cindy Siburian 1, Muhammad R. Fadillah 1, Eka Nurfani 1, Nursidik Yulianto 3, Kuwat Triyana 4,b, Hutomo Suryo Wasisto 5,c 1 Department of Materials Engineering, Institut Teknologi Sumatera, Terusan Ryacudu, Way Hui, Jati Agung, Lampung 35365, Indonesia 2 Research and Innovation Center for Advanced Materials, Institut Teknologi Sumatera, Terusan Ryacudu, Way Hui, Jati Agung, Lampung 35365, Indonesia 3 Research Center for Photonics, National Research and Innovation Agency (BRIN), Kawasan Puspitek Serpong, 15314 Tangerang Selatan, Indonesia 4 Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, Sekip Utara PO Box BLS 21, Yogyakarta 55281, Indonesia 5 PT Nanosense Instrument Indonesia, Umbulharjo, Yogyakarta 55167, Indonesia Abstract Detection of gaseous acetone molecules was remained challenging in the effort for development of new diagnostic methods to identify personal health conditions. Acetone was one of breath biomarker molecules for person with diabetes diseases. In this study we developed an acetone sensor using quartz crystal microbalance platforms coated with tin dioxide nanofibers. The SnO2 nano&#64257-bers were fabricated using electrospinning techniques followed by calcination at 450 deg C for 2 hours. The different amount of Sn precursors (tin (II) chloride dihydrate. SnCl2.2H2O) was used to fabricate the SnO2 nanofibers with a fixed concentration of polyvinylpyrrolidone (PVP). The Scanning electron microscopy (SEM) and x-ray diffraction (XRD) analysis were used to confirms the nanofiber morphology and crystalline structured of the as-prepared nanofibers. The sensing characteristics were investigating in term of sensor sensitivity, detection limit, and selectivity. Different content of Sn in the nanofiber samples influence the sensor performances toward acetone gas. This finding provides an alternative method to fabricates a room-temperature acetone sensors with high-sensing performances. Keywords: acetone- metal oxide- nanofiber- gas sensors- quartz crystal microbalance Share Link | Plain Format | Corresponding Author (Aditya Rianjanu)

92	Sensor	ABS-44
Stearic Acid (SA)-Based Quartz Crystal Microbalance Gas Sensor for Volatile Organic Compound Detection under Low Concentration Masruroh1, a), Dionysius Joseph Djoko Harry Santjojo1, b), Rachmat Triandi Tjahjanto2, c), Arinto Yudi Ponco Wardoyo1, d), and Arif Budianto3 1Physics Department, University of Brawijaya, Jl. Veteran 65145 Malang, Indonesia. 2Chemistry Department, University of Brawijaya, Jl. Veteran 65145 Malang, Indonesia. 3Physics Study Program, University of Mataram, Jl. Majapahit 83125 Mataram, Indonesia. Abstract This work focuses on a monolayer SA (stearic acid) thin film on the surface of a bare QCM (quartz crystal microbalance) to detect VOC (volatile organic compound). SA was used as the sensitive coating material deposited on the surface of QCM by evaporation. This study aims to develop a novel VOC sensor with good performance related to airborne VOC detection in low-range concentrations based on SA-coated and uncoated QCMs. These sensors were connected to an analysis system. Three solutions were aerated to generate volatile gases: ethanol, acetone, and formaldehyde. The sonication duration was varied at 180, 240, 300, and 360 seconds. Gas concentration was calculated by dividing the weighed mass and the constant chamber volume, resulting in a measured concentration. The sensor output was converted into calculated concentration using the Sauerbrey equation. The result shows that the SA-coated sensor has more selectivity in formaldehyde sensing than ethanol and acetone. The sensitivity is up to 2,700 Hz/ppm for formaldehyde sensing (frequency shift > 150,000 Hz). The longest duration has more gas concentration, while the most gas concentration has the most frequency shift. SA-coated QCM has the potential as a formaldehyde gas sensing with good sensitivity, selectivity, and accuracy. Keywords: Keywords: frequency- quartz crystal microbalance- stearic acid- volatile organic compound Share Link | Plain Format | Corresponding Author (Masruroh Masruroh)

93	Sensor	ABS-57
Concentration Dependence of Lorazepam in Sulfuric Acid on Their Fluorescence and Raman Spectra Siti Rohmani Sholikah1, Teguh Endah Saraswati1, a), and Mohtar Yunianto2 Author Affiliations 1Department of Chemistry, Faculty of Mathematics and Natural Sciences, Sebelas Maret University Jl. Ir. Sutami 36A Surakarta 57126 Indonesia 2Department of Physics, Faculty of Mathematics and Natural Sciences, Sebelas Maret University Jl. Ir. Sutami 36A Surakarta 57126 Indonesia Author Email a) Corresponding author: teguh[at]mipa.uns.ac.id Abstract Lorazepam is one of the drugs in the 1,4-benzodiazepines group, which is classified as a schedule IV psychotropic drug. Lorazepam is commonly used in sedative-hypnotic or anxiolytic medication, which can be detected using spectroscopy techniques. Lorazepam has better dissolution in acid compared to water. This study reports the fluorescence and Raman spectra of lorazepam in various concentrations dissolved in sulfuric acid 1 M. The fluorescence spectra show that lorazepam reveals emission at a wavelength of 498.5 nm. The emission intensity regularly increased with the increasing lorazepam concentration, resulting in a standard linear curve with a goodness-of-fit measure for linear regression (R-squared, R2) of nearly 1. The detection of lorazepam by Raman spectroscopy resulted in several peaks appearing at Raman shifts of 676 cm-1, 1032 cm-1, and 1195 cm-1 representing vibrations of N-H ring vibration, C-N stretching vibration, and O-H stretching. However, in Raman spectra, those peak intensities were increased irregularly with the increasing lorazepam concentrations. Keywords: lorazepam- psychotropic drug- fluorescence- Raman- sulfuric acid Share Link | Plain Format | Corresponding Author (Siti Rohmani Sholikah)

94	Sensor	ABS-59
Influence of the electrodeposition scan rate on the microstructure and resonance parameter of Polyaniline film-based QCM sensor Nugrahani Primary Putri, Evi Suaebah, Lydia Rohmawati, D.J. Djoko H Santjojo, Masruroh, Setyawan Purnomo Sakti Universitas Brawijaya Abstract This study investigates the influence of the scan rate on the microstructure and resonance parameter of the PANI thin film deposited at a quartz crystal microbalance (QCM). The PANI thin film was fabricated by electrodeposition method with parameters of scan rate and concentration solution. The solution concentration varies from 0.2 M to 0.5 M, and the electrodeposition scan rate parameter uses 10 mV/s to 50 mV/s. Variations in the scan rate affect the morphology and homogeneity of the PANI thin film. At a lower scan rate, the PANI films formed agglomerations and were not spread evenly. On the other hand, the increasing scan rate until 50 mV/s produce a coarse and dense layer and has a large surface area. The resonance parameters studied include L2 and R2, representing the inertial mass and dissipative properties of the PANI thin film. From the analysis results using the non-linear Generalized Reduced Gradient (GRG) method, it is found that a scan rate of 40 mV/s owns the highest L2 value, this is presumably because the greater the scan rate used, the more homogeneous the morphology of the PANI layer. Scan rate variation also affects the mass of the PANI thin film deposited, this is indicated by the shift in the QCM resonance frequency. The resonant frequency shift is due to the morphological change. Keywords: electrodeposition- polyaniline- QCM- resonance parameter- microstructure Share Link | Plain Format | Corresponding Author (Nugrahani Primary Putri)

95	Sensor	ABS-64
Gold Nanospheres Coating Effect on Laser-Tapered Optical Fiber Sensors N. Hidayat1,2,3,a), M.S. Aziz1,b), G. Krishnan1,c), M.S. Shamsudin1,d), H. Nur4,e), A. Taufiq2,3,f), N. Mufti2,3,g), R.R. Mukti4,h), H. Bakhtiar1,i) 1Laser Center, Ibnu Sina Institute for Scientific and Industrial Research, Universiti Teknologi Malaysia, Skudai 81310, Johor, Malaysia 2Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Negeri Malang, Jl. Semarang 5, Malang 65145, Indonesia 3Center of Advanced Materials for Renewable Energy, Universitas Negeri Malang, Jl. Semarang 5, Malang 65145, Indonesia 4Division of Inorganic and Physical Chemistry, Faculty of Mathematics and Natural Science, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132, Indonesia a)nurulhidayat[at]graduate.utm.my b)safwanaziz[at]utm.my c)k.ganesan[at]utm.my d)msshamsudin[at]graduate.utm.my e)hadi.nur.fmipa[at]um.ac.id f)ahmad.taufiq.fmipa[at]um.ac.id g)nandang.mufti.fmipa[at]um.ac.id h)rino[at]chem.itb.ac.id i)hazri[at]utm.my Abstract Tapered optical fibers have been intensively used as sensors due to their high sensitivity and facile production. In this paper, we reported the characteristics of tapered optical fibers before and after gold nanosphere immobilization. The gold nanospheres, having diameter around 13 nm, were synthesized by the citrate reduction method. The formation of gold nanoparticles was evidenced by UV-Vis and HRTEM data. Self-assembly monolayer approach was conducted to immobilize gold nanoparticles on the surface activated tapered fiber surfaces. The surface activation was done by thiolation process using (3-mercaptopropyl)trimethoxysilane. Single mode and multimode optical fibers were tapered by focusing a CO2 laser beam on the small section of uncladded fibers region. The sensors were tested to detect media with varying refractive indices (1.33 - 1.42). In brief, smaller waist diameter could be obtained by increasing the CO2 laser power. In range of 66-30 micrometer waist diameters, the tapered multimode optical fibers offered better sensitivity than those of tapered single mode optical fibers. More importantly, the gold nanosphere immobilization of the tapered optical fibers could double the sensitivity. Localized surface plasmon resonance of gold nanospheres played crucial role in improving the tapered optical fibers sensitivity. Keywords: Tapered optical fibers, gold nanosphere, CO2 laser, localized surface plasmon resonance. Share Link | Plain Format | Corresponding Author (Nurul Hidayat)

96	Sensor	ABS-65
Effect of Hydrothermal Time On Morphology and Optical Properties of ZnO Nanorod/Graphene Adinda Mahdhury Salsabillah (1), Nurmala Ismawardani (1), Shiswi Pratiwi (1), Melani Fitri Anggraeni (1), Robi Kurniawan (1*) 1) Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Negeri Malang, Jl. Semarang No. 5, Malang 65145, East Java, Indonesia. *robi.kurniawan.fmipa[at]um.ac.id Abstract Abstract. ZnO Nanorod/Graphene was successfully synthesized on an ITO (Indium Tin Oxide) substrate using the hydrothermal method by varying the hydrothermal time of 1 hour, 3 hours, and 5 hours. This study was conducted to confirm the effect of hydrothermal time variations on the structure, morphology, and optical properties of ZnO Nanorod/graphene as a photodetection application. The characterizations used are X-ray diffraction (XRD), Fourier transforms infrared (FT-IR), scanning electron microscopy (SEM), UV-VIS spectrophotometry, and spectroscopic ellipsometry (SE). XRD results show ZnO NRs/Graphene has a wurtzite hexagonal phase with a dominant crystal orientation on the plane (002). Furthermore, the FTIR analysis describes the Zn-O functional groups at wave numbers 598 cm-1 and C=C at wave numbers 1670 cm-1. The results of the SEM analysis confirmed that the ZnO NRs/Graphene form was hexagonal rods with the highest porosity value owned by samples with a hydrothermal duration of 1 hour, which was 67.04%. UV-Vis analysis explained that each sample had a bandgap whose width varied and whose values further increased with the increase in hydrothermal duration of 1 hour, 3 hours, and 5 hours respectively worth 3.14 eV, 3.24 eV, and 3.39 eV. Investigation of light absorption in the sample, analyzed by characterization of ellipsometric spectroscopy and obtained 5-hour ZnO NRs/Graphene samples showed the highest decrease in oscillator amplitude compared to other samples, this indicates more light absorption. Keywords: ZnO Nanorod/Graphene- hydrothermal- ITO- time variations Share Link | Plain Format | Corresponding Author (Adinda Mahdhury Salsabillah)

97	Sensor	ABS-68
Trimethylamine Sensor Based on Quartz Crystal Microbalance Functionalized with Thin Film Based on Polyvinil Acetate and Boric Acid Doping Andi Chaerunnisa Mugni Said, Kuwat Triyana, Nur Aisyah Humairah, Sintia Ainus Sofa Department of Physics, Gadjah Mada University Abstract The development of a sensor based on Quartz Crystal Microbalance (QCM) to detect Trimethylamine (TMA) gas vapor has been carried out. QCM was functionalized with Polyvinyl Acetate (PVAc) doped with Boric Acid (BA) with doping variations of 2%, 4% and 6% as the active layer of QCM with spin coating method. The results showed that QCM with 6% BA doping had the highest sensitivity to detect TMA analytes in the range of 400-1000 ppm. From the test, the sensitivity of QCM with 6% BA doping was 96.7 Hz/ppm with an LOD of 0.19 ppm and an LOQ of 0.58 ppm. QCM tested for 80 weeks showed that with the addition of 6% BA doping, QCM had good stability with an average deviation of 2.34 Hz. Compared to other analytes such as DMA, MA and ammonia, QCM with 6% BA doped has high selectivity to TMA analytes. From some of the results above, it shows that QCM with 6% BA doping is able to detect TMA analyte optimally and can be used as a candidate in making fresh fish detection sensors. Keywords: Quartz Crystal Microbalance- Trimethylamine- Boric Acid- spincoatingt Share Link | Plain Format | Corresponding Author (Andi Chaerunnisa Mugni Said)

98	Sensor	ABS-90
Fabrication and Characterization of Ammonia Sensors Based on Quartz Crystal Microbalance with Molecular Imprinting Polymer Method on Polyvinyl Acetate/Boric Acid Please Just Try to Submit ThisIhsan Nurijal 1,a) - Nur Aisyah Humairah 2,b) - and Ahmad Kusumaatmaja3,c) Sample Abstract Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, Sekip Utara, PO Box BLS 21, Yogyakarta, 55281, Indonesia Abstract The main precursor in kidney failure patients is ammonia, which is a volatile organic compound (VOC). As a gas compound produced by metabolic processes in the body, this compound can be observed in human breath vapor. The detection of ammonia gas is important for tracking the amount of ammonia in the body or describes the extent of renal disease. As a consequence, an ammonia detection sensor was developed in this study using the Molecular Imprinting Polymer (MIP) method based on Quartz Crystal Microbalance (QCM) with Polyvinyl Acetate/Boric Acid polymer using the Molecular Imprinting Polymer (MIP) method based on Quartz Crystal Microbalance (QCM). The QCM PVAc MIP sensor with 6% Boric Acid addition has a sensitivity of 0.10949 Hz/ppm, and that is 2 times greater than the sensitivity of the QCM MIP PVAc without Boric Acid. The QCM PVAc MIP sensor with 6% Boric Acid doping provides good stability, high repeatability with a maximum difference of 0.7 percent, and high selectivity to ammonia if compared to ethanol, methanol, acetone, and benzene. For ammonia gas, the sensor detection limit (LOD) is 53.1 ppm, and the quality limit (LOQ) is 17.5 ppm. The covalent bonding of the boron atom of boric acid and the nitrogen atom of ammonia, the increasing number of hydrogen bonds, the formed mold molecules^ ability to recognize the analyte, and the increase in the surface area of the nanofiber layer all lead to the increased sensitivity and selectivity to ammonia. Keywords: Quartz Crystal Microbalance (QCM)- Molecular Imprinting Polymer (MIP)- Polyvinyl Acetate (PVAc)- Boric Acid- Ammonia. Share Link | Plain Format | Corresponding Author (Ihsan Nurijal)

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