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Penghilangan Interferensi Fe dan Mn dengan Ekstraksi Pelarut pada Penentuan Co dan Cu dalam Pirolusit Menggunakan Spektrometri Serapan Atom Pote, Lodowik Landi; Aprilita, Nurul Hidayat; Suratman, Adhitasari
Berkala Ilmiah MIPA Vol 23, No 2 (2013)
Publisher : FMIPA UGM

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Abstract

Research on the removal of Fe and Mn interference by solvent extraction on the determination of Co and Cu in pyrolusite using atomic absorption spectrometry with an air-acetylene flame have been investigated. Dissolution of pyrolusite sample was done by wet destruction method with solution of aqua regia and HF in the ratio of 3:4 (v/v). Interference studies were carried out for the absorbance of Co and Cu with the addition of iron and manganese in the concentration range 100-1000 ug/mL for iron and 100-5000 ug/mL for manganese measured at the wavelength 240.7 nm and slit width 0.2 nm for Co and wavelength 324.7 nm and slit width 0.7 nm for Cu.The results showed that Fe at concentrations of 100-1000 ug/mL and Mn at the concentrations of 100­5000 ug/mL could interfere the absorbance of Co and Cu, i.e. increase the absorbance of Co and decrease the absorbance of Cu. The interference of Fe can be overcome by solvent extraction with methyl isobutyl ketone in 7 M HCl medium. The interference of Mn can be overcome by masking with 0.10 M EDTA, then Co and Cu were extracted into chloroform by complexing them with sodium diethyldithiocarbamate at pH 2. The content of Fe and Mn in the pyrolusite measured by AAS were 67.35±0.61 mg/g and 545.00±6.25 mg/g, respectively. The content of Co and Cu before extraction were 773.33±25.17 ug/g and 2166.67±101.04 ug/g, respectively and after extraction were 487.18±11.10 ug/g and 2733.33±80.36 ug/g, respectively. These results have high precision with relative standard deviation (RSD) value of each elements less than 5%.
ANALITICAL METHOD VALIDATION OF ANIONIC SURFACTANT SODIUM DODECYL BENZENE SULFONATE (SDBS) IN CATFISH BY UV-VIS SPECTROPHOTOMETRY USING ACRIDINE ORANGE Ratri, Monica Cahyaning; Suratman, Adhitasari; Roto, Roto
ALCHEMY Jurnal Penelitian Kimia Vol 13, No 2 (2017): Alchemy Jurnal Penelitian Kimia
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.13.2.8916.145-165

Abstract

The analytical method development on an anionic surfactant of sodium dodecylbenzenesulfonate (SDBS) in a catfish using spectrophotometer UV-Vis using acridine orange (AO) has been conducted. This research aims to determine the optimum conditions of analysis and to determine validation parameters of sodium dodecylbenzenesulfonate (SDBS) analysis in a catfish. This study was divided into two steps, isolation of sodium dodecyl benzene sulfonate (SDBS) in the catfish with soxhlet extraction and the analysis of SDBS. The analysis of sodium dodecylbenzenesulfonate (SDBS) is based on the formation of ion pair between dodecylbenzenesulfonate (DBS) and acridine orange (AO). The results showed that the analysis can be performed at 499 nm, using ethanol as acridine orange (AO) solvent, the mole ratio of dodecylbenzenesulfonate (DBS) acridine orange (AO) 2:1, and pH 2.97. The parameters of validation had good acceptability as linearity (r) 0.998, limit of detection 0.0343 mg/L   and limit of quantification 0.104 mg/L, precision 0.382 - 1.78 %, sensitivity 4.64 x 104 L mol-1cm-1, and accuracy (82.11 - 100.3 %).
PREVENTION OF PROTEIN ADSORPTION ON BARE FUSED-SILICA CAPILLARY BY PEG IN CAPILLARY ZONE ELECTROPHORESIS Suratman, Adhitasari; Waetzig, Hermann
Indonesian Journal of Chemistry Vol 9, No 3 (2009)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (61.169 KB) | DOI: 10.22146/ijc.21507

Abstract

The protein separation was studied in capillary zone electrophoresis for preventing protein adsorption on the capillary wall. ß-lactoglobulin (pI: 4.83-5.4, Mr: 18.4 kDa), cytochrome c (pI: 9.59, Mr: 11.7 kDa) and ß-casein (pI: 4.6, Mr: 24 kDa) were used as protein models. Strong adsorption of the proteins occurred onto the capillary at a pH around their pIs. In order to prevent protein adsorption, PEG (Poly(ethylene glycol)) was investigated as an effective substance to stabilize the proteins native state and coat the bare fused-silica capillary surface. The presence of 32 mg/mL PEG in buffer solution in a pH range of 6.0 to 4.0 was successful to suppress protein adsorption during the separation. It can also be confirmed with the reproducibility of apparent EOF mobility with percentile RSD (Relative Standard Deviation) less than 2% in long-term measurement.   Keywords: PEG, protein adsorption, CZE
The Fermentation of Green Algae (Spirogyra majuscule Kuetz) using Immobilitation Technique of Ca-Alginate for Saccharomyces cerevisiae Entrapment Wibowo, Atmanto Heru; Mubarokah, Lailatul; Suratman, Adhitasari
Indonesian Journal of Chemistry Vol 13, No 1 (2013)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2584.791 KB) | DOI: 10.22146/ijc.21319

Abstract

A study of batch fermentation of green algae (Spirogyra majuscula Kuetz) from Pengging Lake, Boyolali, Central Java for bioethanol source using immobilization technique of Ca-alginate for Saccaromyces cerevisiae entrapment has been done. The scope of the study emphasized on the best condition for the processes of hydrolysis and fermentation. Concentration of sulfuric acid and hydrolysis time were varied with 0.1, 0.2, 0.3, 0.4 and 0.5 M for 30, 90, 150, 210, 270, 330, 360, 390, 420, and 450 min to obtain the maximum glucose content of UV analysis. Na-alginate : yeast ratio and fermentation time were varied with 1:5, 2:4, 3:3, 4:2 and 5:1 (w/w) for 1, 2, 3, 4, 5, 6 and 7 days. Distillation at 70-80 °C was deployed to purify the fermentation product. The ethanol content in the product was analyzed using gas chromatography-flame ionization detector (GC-FID). The result of study showed that maximum glucose content was obtained 2.1% from 0.2 M sulfuric acid for 6 h of hydrolysis. Maximum ethanol content was obtained 54.1% from 2:4 ratio of Na-alginate : yeast (w/w) for 4 days of fermentation. The study also concludes that immobilization technique of Ca-alginate increase alcohol content compared to without immobilization of green-algae fermentation.
STUDY OF ELECTROPOLIMERIZATION PROCESSES OF PYRROLE BY CYCLIC VOLTAMMETRIC TECHNIQUE Suratman, Adhitasari; Buchari, Buchari; Noviandri, Indra; Gandasasmita, Suryo
Indonesian Journal of Chemistry Vol 4, No 2 (2004)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (932.1 KB) | DOI: 10.22146/ijc.21864

Abstract

Electropolymerization processes and electrochemical properties of polypyrrole as electroactive polymer have been studied by cyclic voltammetric technique. Pyrrole was electropolymerized to form polypyrrole in water-based solvent containing sodium perchlorate as supporting electrolyte in several pH values. The pH of the solutions were varied by using Britton Robinson buffer. The results showed that oxidation potential limit of electropolymerization processes of pyrrole was 1220 mV vs Ag/AgCl reference electrode. It can be seen that cyclic voltammetric respon of polypyrrole membrane that was prepared by electropolymerization processes of pyrrole at the scanning rate of 100 mV/s was stable. While the processes of pyrrole electropolymerization carried out at the variation of pH showed that the best condition was at the pH range of 2 - 6.   Keywords: polypyrolle, electropolymer, voltammetric technique
Effect of Reducing Agents on Physical and Chemical Properties of Silver Nanoparticles Roto, Roto; Rasydta, Hani Prima; Suratman, Adhitasari; Aprilita, Nurul Hidayat
Indonesian Journal of Chemistry Vol 18, No 4 (2018)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (342.594 KB) | DOI: 10.22146/ijc.26907

Abstract

Silver nanoparticles having uniform size and shape, a diameter range of 10–50 nm, excellent stability, and high zeta potential are always desirable for many applications. The silver nanoparticles were synthesized by chemical reduction method using some reducing agents in a polyvinyl alcohol solution. This study aims at determining the effect of reducing agents on the chemical and physical properties of silver nanoparticles. Ascorbic acid, sodium borohydride, hydrazine, sodium citrate, and glucose were used as reducing agents. Surface Plasmon Resonance (SPR) absorbance, morphology, zeta potential, crystal system, and stability of the products were studied. The results showed that the chemical and physical properties of the colloidal Ag nanoparticles were dependent on the reducing agents. In general, the produced silver nanoparticles have an fcc crystal system with a unit cell of 4.0906–4.0992 Å. The SPR absorbance of the colloids has the peak in the range of 401–433 nm. We found that the colloid of silver nanoparticles prepared by using ascorbic acid has uniform spherical shape, the diameter of about 20 nm, and zeta potential of -10.4 mV. After being stored for one month, the SPR absorbance of the colloid decreased by only 5%. This type of colloidal Ag nanoparticles prepared by using ascorbic acid is expected to be used for chemical sensors, an antibacterial agent, and so on.