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AKTIVITAS SULFUR DAN SELENIUM NANOPARTIKEL TERHADAP CACING Steinerma feltiae DAN PERBANDINGAN TOKSISITASNYA TERHADAP SEL NEUROBLASTOMA (NEURO 2A CELL LINES) Khairan Khairan; Rinaldi Idroes; Muhammad Bahi; Karl Herbert Schaefer; Thomas Schneider; Claus Jacob
Jurnal Kedokteran Hewan Vol 9, No 1 (2015): March
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21157/j.ked.hewan.v9i1.2798

Penelitian ini bertujuan mengetahui aktivitas sulfur dan selenium nanopartikel terhadap cacing Steinernema feltiae (S. feltiae) dan perbandingan toksisitasnya terhadap sel neuroblastoma (neuro 2A). Sulfur dan selenium nanopartikel “aqueous nanoparticles” dikarakterisasimenggunakan Nano Zetasizer pada pH 7 dan suhu 25 C. Dalam penelitian ini uji nematoda dilakukan terhadap S. feltiae. Hasil penelitian menunjukkan bahwa sulfur nanopartikel mempunyai aktivitas yang sangat tinggi terhadap S. feltiae dengan lethal dose 50 (LD50) berkisar pada 6,99 μg/ml setelah 24 jam inkubasi. Sementara itu, live and dead assay dilakukan terhadap neuroblastoma sel (Neuro 2A cell lines). Hasil penelitian menujukkan bahwa ‘aqueous’ sulfur nanopartikel (NPS) menunjukkan aktivitas yang lebih baik dibandingkan dengan ‘aqueous’ selenium nanopartikel (NPSe) terhadap sel neuroblastoma (neuro 2A cell lines) dengan IC50 1 μg/ml.

Utilizing of alkybenzene homologous series on the determination of kovats retention index in the RP-HPLC using methanol/water solvent system Rinaldi Idroes
Indonesian Journal of Pharmacy Vol 20 No 2, 2009
Publisher : Faculty of Pharmacy Universitas Gadjah Mada, Yogyakarta, Skip Utara, 55281, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14499/indonesianjpharm0iss0pp77-83

Retention times in high performance liquid chromatography are very susceptible to small changes of the stationary phase, temperature, pH-value, mobile-phase composition and flow rate. One of the methods to minimize theseeffects is by utilizing a retention index system. In contrast to GC, the retention Index determination method in HPLC is still widely discussed, because of difficulty utilizing n-alkane as standard. In addition, the solutes in HPLC interact with the mobile-phase, thus the retention data also depend on the mobilephase. It is not easy to use n-alkane in HPLC as standards because of considerable problems. Due to their very non polar properties, hence in most reversed phase systems, they show large retention times. Therefore, using nalkane in routine analysis could be inconvenient. In comparison with n-alkane, the alkylbenzene homologous series are stable compound and commercially available. They have a high UV absorbance at the wavelength of 254 nm, and thus are easily detected by a UV detector. This paper will introduce Kovats Retention Index Determination in the HPLC by using alkylbenzene homologous series and then is to be connected with n-alkane as a frame of reference. Steroids were used as test substance for determining Kovats retention index values in methanol/ water system.Key words: RP-HPLC, Kovats Retention Index, n-Alkane, Alkyl Benzene.

Evaluation of chromatographic dead times for retention indices determination in RP-HPLC using some homologous series Rinaldi Idroes
Indonesian Journal of Pharmacy Vol 20 No 3, 2009
Publisher : Faculty of Pharmacy Universitas Gadjah Mada, Yogyakarta, Skip Utara, 55281, Indonesia

Dead time that defined as a retention time of unretained substance in the chromatographic coloumn, is needed to determine all retention parameters in coloumn chromatography such as corrected retention time, relative retention time and Kovats Retention Indices.This research reported a comparison between the iteration and linearization of corrected retention times of homologous series such as n-alkane, akylrylketone, alkylbenzene and 2-alkanone. Furthermore the iteration method provides better dead-time values and smaller standard deviations than the linearization method. Moreover, the dead-time calculation obtained according to homologous series is not depending on solvent composition for various homologous series.The n-alkane homologous series show better indication accuracy of fit (S/N) in comparison with other homologous series, thereafter 2-alkanone exhibit the second best adjustment.Keywords: Dead-time evaluation, homologous series, methanol/water solvent, RP-HPLC.

Dead time determination and its influence to retention index in GC system using polar capillary column Idroes, Rinaldi; Oesman, Frida
Indonesian Journal of Pharmacy Vol 22 No 3, 2011
Publisher : Faculty of Pharmacy Universitas Gadjah Mada, Yogyakarta, Skip Utara, 55281, Indonesia

In this research for the determination of dead timeused a method that is mathematically calculated as iteration and linearization of the polar capillarry column in Gas Chromatography (GC) type DN-Wax, by injecting the homologous series of n-alkanes (n-pentane up to n-decane) on GC system. The dead time values obtained are then used to determine the Kovats Retention Index (Retention Index, RI). The results indicated that the retention index had values of systematic error those are more accurate than the retention time (tR), corrected retention time (tR') and retention factor(k'), but the retention index shows the value of random error slightly larger than with other retention parameters. In this study the average values obtained by the iteration method, the dead time was 3.52 minutes with a correlation coefficient of 0.9998.Retention index values obtained are at the confidence level 92.11%-97.06% with the systematic errors 2.04%-7.89%, while the linearization method showed the average value of the dead time 3.3 minutes witha correlation coefficient of 0.9992, but the value of retention index values obtained show that the systematic error is very large.Key words:Dead time, Retention Index, Homologous Series, GC

Utilizing of alkybenzene homologous series on the determination of kovats retention index in the RP-HPLC using methanol/water solvent system Idroes, Rinaldi
Indonesian Journal of Pharmacy Vol 20 No 2, 2009
Publisher : Faculty of Pharmacy Universitas Gadjah Mada, Yogyakarta, Skip Utara, 55281, Indonesia

Retention times in high performance liquid chromatography are very susceptible to small changes of the stationary phase, temperature, pH-value, mobile-phase composition and flow rate. One of the methods to minimize these effects is by utilizing a retention index system. In contrast to GC, the retention Index determination method in HPLC is still widely discussed, because of difficulty utilizing n-alkane as standard. In addition, the solutes in HPLC interact with the mobile-phase, thus the retention data also depend on the mobilephase. It is not easy to use n-alkane in HPLC as standards because of considerable problems. Due to their very non polar properties, hence in most reversed phase systems, they show large retention times. Therefore, using nalkane in routine analysis could be inconvenient. In comparison with n-alkane, the alkylbenzene homologous series are stable compound and commercially available. They have a high UV absorbance at the wavelength of 254 nm, and thus are easily detected by a UV detector. This paper will introduce Kovats Retention Index Determination in the HPLC by using alkylbenzene homologous series and then is to be connected with n-alkane as a frame of reference. Steroids were used as test substance for determining Kovats retention index values in methanol/ water system.Key words: RP-HPLC, Kovats Retention Index, n-Alkane, Alkyl Benzene.

Evaluation of chromatographic dead times for retention indices determination in RP-HPLC using some homologous series Rinaldi Idroes
Indonesian Journal of Pharmacy Vol 20 No 3, 2009
Publisher : Faculty of Pharmacy Universitas Gadjah Mada, Yogyakarta, Skip Utara, 55281, Indonesia

Dead time that defined as a retention time of unretained substance in the chromatographic coloumn, is needed to determine all retention parameters in coloumn chromatography such as corrected retention time, relative retention time and Kovats Retention Indices.This research reported a comparison between the iteration and linearization of corrected retention times of homologous series such as n-alkane, akylrylketone, alkylbenzene and 2-alkanone. Furthermore the iteration method provides better dead-time values and smaller standard deviations than the linearization method. Moreover, the dead-time calculation obtained according to homologous series is not depending on solvent composition for various homologous series.The n-alkane homologous series show better indication accuracy of fit (S/N) in comparison with other homologous series, thereafter 2-alkanone exhibit the second best adjustment.Keywords: Dead-time evaluation, homologous series, methanol/water solvent, RP-HPLC.

AKTIVITAS BEBERAPA SENYAWA TURUNAN BENZOPIRAN (CHROMONES) DAN BENZOFURANON (COUMARANONES) TERHADAP Steinernema feltiae (The Activities of Benzopyran (Chromones) and Benzofuranones (Coumaranones) Derivatives against Steinernema feltiae) Khairan Khairan; Muhammad Bahi; Claus Jacob; Rinaldi Idroes
Jurnal Kedokteran Hewan Vol 10, No 1 (2016): March
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21157/j.ked.hewan.v10i1.3368

This study was purposed to inquire the activities of benzopyran (chromones) and benzofuranones (coumaranones) derivatives against Steinernema feltiae (S. feltiae). The toxicity assay against S. feltiae showed that benzopyran derivatives 2, 3, 4, 6, and 9 have the highest activity on S. feltiae with viabilities percentage of 50%. The compound 9 demostrated the highest activity with LD 50 and LD values, 7.2 and 52.2 μM, respectively. The activities of compound 7 and 10 showed the lowest toxicity. Interestingly, the activity of benzofuranone derivatives showed significant activities against S. feltiae. Compare to benzopyran derivatives, the benzofuranone derivatives has the highest toxicity, in particular compound 13 with LD 5.45 μM. The nematicidal assay showed that benzofuranones (coumaranones) derivatives revealed higher activities than benzopyran (chromones) derivatives.Key words: chromones, benzopyran, coumaranones, benzofuranone, and Steinernema feltiae

ISOLASI ANTIBIOTIK REDUKTIOMISIN DARI BAKTERI TERRESTRIAL Streptomyces sp Muhammad Bahi; Rinaldi Idroes
Jurnal Kedokteran Hewan Vol 7, No 2 (2013): September
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21157/j.ked.hewan.v7i2.925

Penelitian ini bertujuan melakukan isolasi dan penentuan aktivitas mikrobial senyawa bioaktif reduktiomisin dari bakteri Streptomyces sp. Ank181 daratan (terrestrial). Penelitian ini dilaksanakan di laboratorium kimia organik, Institute of Organic and Biomoleculare Chemistry, University of Goettingen, Germany. Isolat dan subkultur agar bakteri Streptomyces sp. Ank181 diperoleh dari koleksi sampel genus Streptomyces Professor Dr. H. Anke, Institute for Biotechnology and Drug Research, Kaiserslautern, Germany. Struktur reduktiomisin dalam penelitian ini dielusidasi berdasarkan data spektroskopi dan spektrometri massa. Tiga senyawa metabolit sekunder telah berhasil diisolasi dan diidentifikasi dari bakteri tanah genus Streptomyces sp. Ank181, yaitu reduktiomisin, asam 2,3-dihidroksibenzoat, dan asam indole-3-karboksilat. Hasil uji antimikroba menunjukkan bahwa reduktiomisin bersifat bioaktif terhadap bakteri, jamur dan sitotoksik terhadap Artemia salina.

Hydrogen Desorption Properties of MgH2 + 10 wt% SiO2 + 5 wt% Ni Prepared by Planetary Ball Milling Malahayati Malahayati; Evi Yufita; Ismail Ismail; Mursal Mursal; Rinaldi Idroes; Zulkarnain Jalil
Bulletin of Chemical Reaction Engineering & Catalysis 2021: BCREC Volume 16 Issue 2 Year 2021 (June 2021)
Publisher : Department of Chemical Engineering - Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.16.2.10220.280-285

MgH2 is a very hopeful material for application as hydrogen storage material in the solid form. This is due to its reversibility and its ability to store large amounts of hydrogen, which is 7.6 wt%. However, this material still has weaknesses, namely high operating temperature and slow kinetic reactions. Various attempts have been made to overcome this weakness, including downsizing and adding catalyst. In this study, double catalyst was used, namely natural silica extracted from rice husk ash and nickel nano powder, with a composition of MgH2 + 10 wt% SiO2 + 5 wt% Ni. The purpose of this research was to study the effect of downsizing and using these catalysts to the thermodynamic and kinetic properties of the hydrogen storage material MgH2. Samples were prepared by using High Energy Ball Milling (HEBM), with variations in milling time of 1, 5, 10, and 15 hours. The X-ray Diffraction (XRD) pattern showed the presence of an impurity phase in the samples milled for 10 and 15 hours. It also showed a reduction in grain size with increasing milling time. However, agglomeration has occurred in the samples milled for 15 hours. From the Scanning Electron Microscope (SEM) results can be seen that the sample with longer milling time, were homogeneously distribute. Thermal investigation showed that the lowest desorption temperature was achieved in samples with milling time of 5 and 10 hours, namely 287 °C and 288 °C. This study shows that natural silica catalyst plays a role in improving the thermodynamic characteristics of MgH2, while Ni plays a role in improving the kinetic characteristics of MgH2. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

ALKYLARYLKETONE HOMOLOGOUS SERIES FOR DETERMINATION OF KOVATS RETENTION INDICES WITH RP-HPLC USING ACETONITRILE/WATER SYSTEM Rinaldi Idroes
Indonesian Journal of Chemistry Vol 10, No 1 (2010)
Publisher : Universitas Gadjah Mada

Some factors such as the changes of the stationary phase, temperature, pH-value, mobile-phase composition and flow rate play a crucial role in effecting the sensitivity of retention times in high performance liquid chromatography (HPLC) system. Utilizing a retention index system is one of the methods to minimize those effects. Besides the mentioned factors, dead-time influences on determining the retention index as well. In comparison with Gas Chromatography (GC), the retention Index determination method in HPLC is still widely discussed, due to the difficulty of utilizing n-alkane as standard. In addition, the solutes in HPLC interact with the mobile-phase, thus the retention behavior also depend on the mobile-phase. Actually, It is difficult to use n-alkanes in HPLC as standards in case of some considerable problems, due to they are very non polar but also large retention times which lack of chromophores. Therefore, using n-alkane in routine analysis could be inconvenient. In comparison with n-alkanes, the alkylarylketones homologous series are stable compounds, commercially available and easily detected by a UV detector. This paper introduces Determination of Kovats Retention Index in the HPLC using Alkylarylketone homologous series and then is connected with n-alkane as a frame of reference. Steroids were used as test substance for calculating Kovats retention index values in acetonitrile/water system.

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