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IMPRINTING ZEOLITE-MODIFIED GLASSY CARBON AS A VOLTAMMETRIC SENSOR FOR URIC ACID Miratul Khasanah; Muji Harsini; Alfa Akustia Widati
Indonesian Journal of Chemistry Vol 13, No 2 (2013)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (248.929 KB) | DOI: 10.22146/ijc.21292

Abstract

Development of the uric acid sensor through coating of glassy carbon (GC) electrode with imprinting zeolite (IZ) was carried out. Zeolite was synthesized by mixing TEOS, TBOT, TPAOH, and water followed by hydrothermal process. Zeolite was molded together with uric acid to produce IZ. The deposition potential of IZ and uric acid to the GC surface was -0.6 V during 150 sec with addition of KNO3 0.02 M as supporting electrolyte. The method gives linearity of 0.9834 (concentration 5.6x10-9M - 2.8x10-8 M), precision 1.89 - 7.65%, sensitivity 0.33 µA/nM/cm2, limit of detection 5.9x10-9 M, and accuracy 96.26 ± 0.55% (n = 5). The developed sensor showed a high selectivity toward uric acid. The presence of ascorbic acid, creatine, and creatinine with an equal concentration with uric acid did not interfere on the uric acid analysis.
Imprinted Zeolite Modified Carbon Paste Electrode as a Selective Sensor for Blood Glucose Analysis by Potentiometry Miratul Khasanah; Alfa Akustia Widati; Usreg Sri Handajani; Muji Harsini; Bahrotul Ilmiah; Irene Dinda Oktavia
Indonesian Journal of Chemistry Vol 20, No 6 (2020)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.49820

Abstract

Imprinted zeolite modified carbon paste (carbon paste-IZ) electrode had been developed as a sensor to analyze blood glucose content by potentiometry. The used zeolite was Lynde Type A (LTA) that synthesized with a mole ratio of Na2O, Al2O3, SiO2 and H2O of 4:1:1.8:270, respectively while non-imprinted zeolite was prepared with a mole ratio of glucose/Si of 0.0306. Glucose was then extracted from the zeolite framework using hot water (80 °C) to produce imprinted zeolite (IZ). The carbon paste-IZ electrode prepared from activated carbon, paraffin pastilles, and IZ with a mass ratio of 5:4:1 showed the best performance. The modified electrode demonstrated the measurement range of 10–4-10–2 M, the Nernst factor of 29.55 mV/decade, the response time less than 120 s, and the detection limit of 5.62 × 10–5 M. Ascorbic acid, uric acid, urea and creatinine did not interfere on the glucose analysis by potentiometry. Comparison test with spectrophotometry showed an accuracy of (90.7 ± 1.4)% (n = 5), while the application of the electrode to analyze five spiked serum samples showed recovery of (92.2 ± 1.3)% (n = 5). The electrode was stable for up to 9 weeks (168 times usage). Based on its performance, the developed electrode can be applied to analyze glucose in human serum sample and recommended for used in the medical field.
SOSIALISASI MANFAAT DAN PEMBUATAN NATTO DAN SOY YOGURT MELALUI KEGIATAN WEBINAR DAN PRAKTEK Sri Sumarsih; Afaf Baktir; Fatiha Khairunnisa; Muji Harsini; Aning Purwaningsih; Siti Wafiroh; Hartati Hartati; Purkan Purkan; Sofijan Hadi
Jurnal ABDI: Media Pengabdian Kepada Masyarakat Vol. 7 No. 1 (2021)
Publisher : Universitas Negeri Surabaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26740/ja.v7n1.p103-107

Abstract

Natto and Soy Yogurt are fermented food products that are very beneficial for improving health. This community service activity aims to socialize the benefits and make them known to the wider community. However, community service activities during the Covid-19 pandemic cannot be carried out face-to-face and have activities with the community in large numbers. Therefore, this community service activity was carried out through webinar and practical activities. Online seminars was chosen so that the coverage was wider and more people could participate in the pandemic. Face-to-face and community activities are carried out with a limited number of participants, according to health protocols. The level of success, benefit and acceptance of the community from this community service activity is known from the responses of the participants during the activities. Based on the results of the assessment/ response of participants who were present virtually and those present at the location, In general it can be concluded that the PKM activity entitled "socializing the benefits and making natto and soy yogurt through webinars and practices" is going well, but better preparation is still needed.The material presented by the resource person is suitable for the current pandemic conditions, easy to understand, easy to practice and can be developed for home businesses. The Zoom Meeting application can be used as a medium for community service activities in pandemic conditions even though it still cannot reach the wider community.  Keywords: Socialization, natto, soy yogurt, webinar, practical
Simultaneous Analysis of Dopamine and Ascorbic Acid Using Polymelamine/Gold Nanoparticle-Modified Carbon Paste Electrode Muji Harsini; Ainy Nur Farida; Erna Fitriany; Denok Risky Ayu Paramita; Afaf Baktir; Fredy Kurniawan; Satya Candra Wibawa Sakti; Yudhi Dwi Kurniawan; Bernadeta Ayu Widyaningrum
Indonesian Journal of Chemistry Vol 24, No 1 (2024)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.83301

Abstract

Modification of electrode using polymelamine (PM) and gold nanoparticles (AuNPs) has been successfully developed via electropolymerization and electrodeposition onto carbon paste electrode (CPE) using cyclic voltammetry (CV) technique. The modified electrode (AuNPs/PM/CPE) was applied as voltammetry sensors in a simultaneous of dopamine (DA) and ascorbic acid (AA). AuNPs/PM/CPE presented an effective surface area 5 times wider than CPE and demonstrated good electrocatalytic performance in the oxidation of DA and AA in 0.1 M phosphate buffer solution (pH 3) with a scan rate of 100 mV s−1. The differential pulse voltammetry (DPV) technique was chosen as the best method for separating potential peaks of DA and AA. The linear response for determining DA and AA using the DPV technique produced a concentration range of 0.1–13 and 0.4–12 µM with coefficient linearity of 0.9999 and 0.9997, the limit of detection of 0.1405 and 0.2187 µM, the accuracy of 89.62–109.16%, and 83.63–105.08%, and the precision of 0.017–0.701% and 0.066–0.626%, respectively. In addition, this electrode was applied in a real sample of infant urine with a concentration of 1 µM by spike method and found 98.86 and 98.28% as percent recovery of DA and AA, respectively.
KEMUNGKINAN PENGGUNAAN NANO KARBON DARI LIGNOSELULOSA SEBAGAI BIOSENSOR Gustan Pari; Adi Santoso; Djeni Hendra; Buchari; Akhirudin Maddu; Mamat Rachmat; Muji Harsini; Bunga Ayu Safitri; Teddi Heriyanto; Saptadi Darmawan
Jurnal Penelitian Hasil Hutan Vol. 34 No. 2 (2016): Jurnal Penelitian Hasil Hutan
Publisher : BRIN Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20886/jphh.2016.34.2.111-125

Abstract

In the forest products field, the nano technology that can be developed is among others nano carbon derived from lignocellulosic stuffs. In relevant, this paper observes information and technology on the charcoal processing from lignocellulosic stuffs into nano carbon. The lignocellulosic stuffs used in this research consisted of teak wood, further carbonized into charcoal at 400-500 C using drum kiln and then purified by re-carbonizing it at 800 C for 60 minutes by using steam and sodium hydroxide (KOH) 15% as activation agent. Prior to purification, the charcoal sustained the doping (intercalation) process with Nicel and re-carbonize again at 900 C for 60 minutes. The qualities and structure of all the resulting carbon were evaluated using nano scale device pyrolysis-gas chromatography mass spectrophotomtry (PyGCMS), scanning electron microscope-energy disverse spectrophotometry (SEM-EDS and X-ray diffraction (XRD), and examined as well of their dielectric characteristics. Result show charcoal was examined of its physical and chemical properties. Manufacture of biosensor by using molecularly imprinted polimer (MIP) system based on carbon paste and optimizing. Results show that nano carbon from lignocellulose can be made for biosensor with MIP system. Optimized formulation were mixed with15% MIP, 45% carbon and 40% parafine with nernst factor of 49 mV/decade and limit detection of 1.02x10-6 M at pH4.
KARAKTERISASI STRUKTUR NANO KARBON DARI LIGNOSELLULOSA Gustan Pari; Adi Santoso; Djeni Hendra; Buchari; Akhirudin Maddu; Mamat Rachmat; Muji Harsini; Teddi Heryanto; Saptadi Darmawan
Jurnal Penelitian Hasil Hutan Vol. 31 No. 1 (2013): Jurnal Penelitian Hasil Hutan
Publisher : BRIN Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20886/jphh.2013.31.1.75-91

Abstract

The science advancement in this century is such that in the future it will enter the nano technology. More specifically in the forest products field, the nano technology that can be developed is among others nano carbon derived from lignocelulosic stuffs. In relevant, this research aims to provide information and technology on the charcoal processing from lignocellulosic stuffs into nano carbon. The lignocellulosic stuffs used in this research consisted of teak wood and bamboo, further carbonized into charcoal at 400-500°C using drum kiln. The resulting charcoal was examined of its physical and chemical properties, crystalinity degree and dielectric characteristics, and then purified by re-carbonizing it at 800°C for 60 minutes. Prior to the purification, the charcoal sustained the doping (intercalation) process with Zn, Ni and Cu metals each respectively. After the purification, the charcoal was ground to very tiny particels using HEM (high energy machine) device for 48 bours. In this way, the charcoal with high crystalinity was yielded, and further sintered using spark plasma at 1,300 C into the nano carbon. The qualities and structure of all the resulting carbon (carbonized charcoal, re-carbonized charcoal, intercalated charcoal and sintered nano carbon) were evaluated using nano scale device (Py-GCMS, SEM-EDX and XRD), and examined as well of their dielectric characteristics. In turns out that the best quality charcoal was obtained from teak wood charcoal carbonized at 800°C, intercalated with Ni atoms at the ratio 1:5. The resulting charcoal afforded high crystalinity (78.98%), low electric resistance (0.17 2), and high conductivity 175.52 2'm Qualities of the corresponding nano carbon (after sintering) were such that its crystalinity spectaculary reached 81.87%, resistance (R) 0.01 & with very bigh conductivity 1067.262'm'. The nano carbon that resulted seems favorably prospective for bio-censor, bio-battery, and bio-electrode. Accordingly futher related research deserves carrying out.
POTENSI STRUKTUR NANO KARBON DARI BAHAN LIGNOSELULOSA KAYU JATI DAN BAMBU Gustan Pari; Adi Santoso; Djeni Hendra; Buchari; Akhirudin Maddu; Mamat Rachmat; Muji Harsini; Teddi Her anto; Saptadi Darmawan
Jurnal Penelitian Hasil Hutan Vol. 34 No. 4 (2016): Jurnal Penelitian Hasil Hutan
Publisher : BRIN Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20886/jphh.2016.34.4.309-322

Abstract

Nanotechnology research in the realm of forest products can be exploited from lignocellulose into nano carbon. The research was aimed to provide the potency of nano carbon structure from lignosellulose as bioenergy or biosensor material. O The materials of teak wood and bamboo were carbonized into charcoal at 400-500 C followed by activation using O chemical and physical processes at 800 C for 60 minutes. This process produced charcoal with high crystalinity and surface area. After purification and activation, the activated charcoal was subsequently doped process with Zn and Ni metals which O then followed by sintering using spark plasma at 1300 C. The qualities and structure of all the resulting carbon were evaluated using nano scale devices i.e. Pyrolysis Gas Chromatography Mass Spectrometer, Scanning Electron Microscope Energy Diffraction X-ray Spectrometer, X-ray Diffractometer, I-V meter and potensiometer. Results showed that the best activated charcoal produced from the chemical-physical activation (KOH steam) possessed high fixed carbon of 84.29%; 2 surface area of 850.5 m /g, crystallinity of 38,99% and resistancy of 0.10. The teak activated charcoal which intercalated by Ni at ratio of 1:5 produced the best properties with crystallinity degree of 73.45% and conductivity of 433.86 S/m. The sintered teak activated charcoal had crystallinity degree of 78.29% with I-V meter pattern in sigmoid shape and the potentiometer response formed a slope approaching the Nerst factors. Nano carbon produced from lignocellulose is a semiconductor and more suitably use for biosensors, particularly the one derived from teak wood.