Study of Electropolimerization Processes of Pyrrole by Cyclic Voltammetric Technique = Studi Proses Elektropolimerisasi Pirol dengan Teknik Voltametri Siklis.

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/AgC1 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 â 6. Keywords: polypyrolle, electropolymer, voltammetric technique

PREVENTION OF PROTEIN ADSORPTION ON BARE FUSED-SILICA CAPILLARY BY PEG IN CAPILLARY ZONE ELECTROPHORESIS

ABSTRACT The protein separation was studied in capillary zone electrophoresis for preventing protein adsorption on the capillary wall. /3-/actoglobulin(pI: 4.83-5.4, M,: 18.4kDa), cytochrome c (pI: 9.59, M,: 11.7kDa) and /3-casein(pI: 4.6, M,: 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(ethyleneglycol» 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,CZ

Kapillarelektrophorese in der Proteinanalytik Strategien zur Vermeidung der Proteinadsorption und Methodenentwicklung für die Elektrophorese mit beschichteten Kapillaren

In order to prevent protein adsorption on the capillary surface and increase the reproducible protein analysis, some strategies were applied in capillary zone electrophoresis (CZE) and isoelectric focusing (CIEF). Three model proteins were used: cytochrome c (basic), ß-lactoglobulin (acidic) and ß-casein (more easily denaturing). The application of polydimethylacrylamide as a coating for silica offers better reproducibility of the apparent EOF mobility compared to bare fused-silica capillaries and good stability in long-term protein separation. Poly(ethylene glycol) 32 mg/mL was proven as an effective substance to stabilize the proteins native state and coat the bare fused-silica capillary surface (RSD%5%. For these conditions, the further test of 85%(m/m) phosphoric acid as rinsing reagent showed good results. Hydrochloric acid 3M was also investigated to improve the precision on protein analysis using LPA-coated capillaries in CIEF. It was performed after each run. Further improvements in precision have been obtained by avoiding a complete stand still of liquid within the capillary when the separation system was idle. Pressure and high voltage were applied to prevent assumed bulged structures on the coated capillaries during storage. Consecutive runs without capillary storage and decreasing the focusing time can also reduce the protein precipitation during routine analysis. Good reproducibility of migration time and peak area was achieved with RSD%≤5%.Um Proteinadsorption an der Kapillaroberfläche zu verhindern und die Reproduzierbarkeit der Proteinanalyse zu verbessern, wurden verschiedene Strategien für Kapillar-Zonenelektrophorese (CZE) und Kapillar-Isoelektrische Fokussierung (CIEF) untersucht. Drei Modellproteine wurden benutzt: Cytochrom c (basisch), β-Lactoglobulin (sauer) und β-Casein (leicht denaturierend). Polydimethylacrylamid-beschichtete Kapillaren boten gegenüber den unbeschichteten eine bessere Reproduzierbarkeit der scheinbaren Mobilität des elektroosmotischen Flusses (EOF) und hohe Stabilität für die Proteinanalyse über einen langen Zeitraum. Polyethylenglycol (32 mg/mL) erwies sich als effektives Reagens zur Stabilisierung der Proteine im nativen Zustand wie zur Beschichtung der Kapillaroberfläche (RSD%5%. Hier lieferte die Verwendung von Phosphorsäure 85%(m/m) gute Ergebnisse. Salzsäure (3M) wurde außerdem benutzt, um die Präzision der CIEF in LPA-beschichteten Kapillaren zu erhöhen, wobei die Spülungen nach jedem Lauf durchgeführt wurden. Durch Anlegen von Druck und Hochspannung während der Leerlaufzeiten wurde ein Stillstand der Flüssigkeit in der Kapillare vermieden, was die Präzision zusätzlich steigerte. Dies wirkt auch der Bildung von Auswölbungen in der beschichteten Kapillarwand entgegen, die vermutlich während der Lagerung der Kapillare entstehen. Fortlaufende Analysen ohne Lagerung der Kapillare und eine reduzierte Fokussierungszeit konnten die Ablagerung von Proteinen während der Routineanalyse ebenfalls verhindern. Eine gute Reproduzierbarkeit von Migrationszeit und Peakfläche (RSD%≤5%) wurde erreicht

Immobilization of Pseudomonas aeruginosa FNCC-0063 on Calcium Alginate and Its Application as Bioabsorbent

Biosorption of Cu (II) using bacteria Pseudomonas aeruginosa FNCC-0063 was immobilized on calcium alginate (PAI). This research examined the effect of various parameters such as pH, contact time, and initial Cu (II) concentration. The biosorption mechanism of Cu (II) was studied by sequential desorption with H2O, KNO3 1 M, HNO3 0.5 M and Na2EDTA 0.1 M. Cu (II) concentration was analyzed using atomic absorption spectrophotometer (AAS). The results showed that optimum Cu (II) ion biosorption occurred at a pH biosorption rate constant of 0.03724 g mg-1.min-1. The kinetics studies showed that Cu (II) biosorption follows pseudo-second-order. The biosorption capacities of 36.60 mg/g. Cu (II) Biosorption followed the Freundlich equation, as shown by a high correlation coefficient (R2) of about 0.99. Ionic bonds dominated the biosorption mechanism of Cu (II) ion on immobilized PAI

Validation of Spectrophotometric Method for Analysis of Anionic Surfactant Dodecyl Benzene Sulphonate (DBS) in Catfish (Clarias batrachus) Using Malachite Green

Validation method of DBS anionic surfactant analysis on Clarias batrachus has been conducted. The method of analysis was divided into twophase, namely the extraction with solid-liquid extractionusing Soxhlet and analysis DBS. The extraction was performed using n-hexane and methanol for 9 and 6 hours, respectively. The analysis was performed using Spectrophotometer UV-Vis based on the complex formation of surfactant-malachite green (DBS-MG). These methods are applied to determine DBS accumulation of Clarias batrachus with DBS concentration exposure and DBS concentration of Clarias batrachus in markets. The result showed that the parameters of validation methods has high acceptability as linearity (R2 = 0.99), limit of detection (LOD) and limit of quantification (LOQ) (0.029 mg/L and 0.089 mg/L), sensitivity (ε = 38.15 × 104 L mol-1 cm-1), precision (RSD = 0.10-1.83 %) and accuracy (recovery = 80-92 %). The result of analysis of DBS in Clarias batrachus with 2.5; 5; 10; 15 mg/L of DBS concentration exposure obtained 5.5; 6.8; 7.9; 8.7 mg/L respectively and Clarias batrachus from markets in a range 2.0-4.2 mg/L. The result showed that the analysis of DBS anionic surfactants using MG can be applied for Clarias batrachus. Keywords: validation method, extraction, clarias batrachus, dodecyl benzene sulfonate, malachite gree

Adsorption of carbon dioxide with nanofibers based on alginate/polyethylene oxide/triton X-100

Nanofiber is a material composed of nanometer-scale fibers with carbon or polymer base materials.The easiest and most economical method of nanofiber synthesis is electrospinning. The most economical method of nanofibers synthesis is electrospinning.Nanofiber has the high potential for CO 2 adsorption because it has high gas transport resistance and high kinetic (Wang and Li, 2014). Nanofiber has a high potential for CO2 adsorption because it has high gas transport resistance and high kinetic [1].Application of synthetic polymer-based nanofiber for CO 2 adsorption has been carried out by several researchers including PVDF nanofiber (Hong et al., 2014), phenolic resin nanofiber (Nan et al., 2015), and PDMS/PVDF nanofiber (Lin et al., 2016). Research on the synthesis of Alginate/Polyethylene oxide/Triton X-100 nanofibers (Alg/PEO/TX NFS) by electrospinning method for CO 2 adsorption was carried out.Research on synthesis of Alginate/Polyethylene oxide/Triton X-100 nanofibers (Alg/PEO/TX NFs) by electrospinning for CO2 adsorption was carried out.This study aims to determine the composition of Alg/PEO that can produce fibers without beads; The purpose of this research werethe effect of adding PEO and TX to the electrospinnability of the solution ; to study the effect of adding PEO and TX to the electrospinnability of the solution, andthe effect of flow rate and contact time on adsorption capacity; the effect of the gas flow rate and contact time on adsorption capacity and the study of CO 2 adsorption isotherm by Alg/PEO/TX NFS.of  Alg/PEO/TX NFs.Polymer solutions were characterized by conductivity meters and tensiometers, while nanofibers were analyzed using optical microscopy, SEM, and FTIR. Polymer solutions were characterized by the conductivity meter and tensiometer, while the nanofibers were analyzed using optical microscopy, SEM, and FTIR.The study of CO 2 adsorption in nanofiber includes the effect of flow rate and CO 2 contact time on nanofiber, then studied adsorption isotherm. The study of CO2 contact time includes the effect of flow rate and CO2 contact time on nanofiber. The results showed that Alg/PEO/TX NFS without beads were successfully synthesized from a solution of Alg/PEO with a volume ratio of 1:2 and an addition of 0.5% (v/v) TX.The results showed that Alg/PEO/TX NFs were successfully synthesized with a volume ratio 1/2 of Alg/PEO blends solutions and a small addition of 0.5% (v/v) TX.The bead s without nanofiber produced were 201,567 ± 48 nm in diameter and have a surface area of 34,963 m 2 g -1 . The beads-free nanofibers produced was 201 ± 48 nm in diameter and with a surface area of 34,963 m2.g-1.The optimum adsorption capacity was obtained at the rate of 10 mL minute -1 with a contact time of 25 minutes was 12,398 mmol g -1 . The optimum adsorption capacity was 12,398 mmol.g-1, which wasobtained at the flow rate of 10 mL.minute-1 and a contact time of 25 minutes

Air Pollution Simulation From Cirebon Power Plant Activity

Telah dilakukan penelitian simulasi sebaran polutan dari aktivitas PLTU Cirebon dengan menggunakan model gaussian plume. Persamaan gaussian plume digunakan untuk memprediksikan persebaran dan konsentrasi gas polutan di udara. Tujuan dari penelitian ini adalah untuk mengetahui konsentrasi polutan di udara ambien akibat dari aktivitas PLTU dan pemodelan dispersi polutan di udara yang berasal dari dua cerobong asap. Hasil penelitian menunjukkan bahwa konsentrasi maksimum untuk semua parameter masih berada di bawah baku mutu yang telah ditetapkan. Adapun konsentrasi maksimum untuk parameter SOx sebesar 36,89 µg/m3 sedangkan NOx adalah 31,25 µg/m3. Sedangkan simulasi dengan menggunakan dua cerobong asap konsentrasi maksimum SOx sebesar 52,95 µg/m3 dan NOx sebesar 44,86 µg/m3

Sintesis Membran Matriks Tercampur Alginat/Zeolit Alam /Kaolin Untuk Pemisahan Gas CO2 dan CH4

Telah dilakukan sintesis membran matriks tercampur (Mixed Matrix Membranes, MMMs) alginat/zeolit alam/kaolin untuk pemisahan gas CO2 dan CH4. Penelitian ini bertujuan mempelajari pengaruh variasi konsentrasi kandungan MMMs, ketebalan MMMs serta membandingkan pengisi anorganik multi komponen dengan komponen tunggal terhadap permeabilitas dan selektivitas CO2 dan CH4. Sintesis MMMs alginat/zeolit/kaolin dilakukan dengan mendispersikan zeolit:kaolin berdasarkan rasio berat 3:1 ke dalam larutan alginat dengan berbagai variasi konsentrasi kandungan dan ketebalan MMMs. MMMs alginat/zeolit/kaolin hasil sintesis dikarakterisasi dengan FTIR dan SEM serta dilakukan uji tarik mekanik untuk melihat kuat tarik dan persen perpanjangannya. MMMs alginat/zeolit/kaolin diuji permeabilitas dan selektivitas terhadap gas CO2 dan CH4berdasarkan variasi konsentrasi kandungan MMMs, variasi ketebalan MMMs dan perbandingan pengisi multi komponen dengan komponen tunggal. Hasil penelitian menunjukkan bahwa dispersi zeolit dan kaolin dalam MMMs terjadi secara homogen. Penambahan zeolit dan kaolin dalam membrane alginat menurunkan kuat tarik dari 27,94 MPa menjadi 18,92 MPa dan meningkatkan persen perpanjangan dari 3,07% menjadi 3,67% pada kondisi MMMs optimum. Perbandingan konsentrasi optimum alginat/zeolit/kaolin dalam MMMs adalah 1,50:0,30:0,10 % (b/v) dengan ketebalan efektif adalah 0,07 mm dan menghasilkan nilai permeabilitas CO2   5,15 GPU dan CH41,27 GPU dengan selektivitas 4,06.

Validation of Analytical Method Determination of Sodium Dodecyl Benzene Sulfonate (DBS) in Catfish (Clarias batrachus L.) by Spectrophotometric Using Methylene Blue

A spectrophotometric method for analysis of DBS anionic surfactant in Clarias batracus has been validated. The method of analysis was divided into two phases. Extraction with solid-liquid extraction using Soxhlet and analysis of DBS. The extraction was performed using solvent of n-hexane and methanol for 9 and 6 hours, respectively. The analysis was performed using Spectrophotometer UV-Vis based on the complex formation of DBS-methylene blue (DBS-MB). This methods is applied to the determination of DBS in local catfish after DBS exposure and that of obtained in markets. The results showed that the parameters of validation methods have high acceptability as linierity (R2 = 0.99), limit of detection (LOD) and limit of quantification (LOQ ) (2.93 mg/g and 9.75 mg/g), sensitivity (ε = 2.44 x 105 L mol-1 cm-1), precision (RSD = 0.14-1.38%) and accuracy (% recovery in a range 82-110 %). The results of analysis of DBS in catfish with 2.5; 5; 10; 15 mg/L of DBS concentration exposure are 0.87; 1.67; 8.50 and 18.10 mg/kg, respectively and catfish from markets in a range 8.5-61 mg/kg. The result showed that the method of analysis of DBS anionic surfactant using MB could be applied for catfish samples. Keywords: Validation methode, extraction, catfish, Clarias batrachus, dodecyl benzene sulfonate, methylene blue

Glutaraldehyde Crosslinked Alginate-Chitosan Nanoparticles as Paracetamol Adsorbent

Paracetamol contained in wastewater can cause adverse effects on animal ecosystems, such as fish living in waters and cause harmful effects on humans. Adsorption techniques are used to remove these pharmaceutical compounds. Alginate-chitosan nanoparticles are non-toxic and effectively used as adsorbents to remove pharmaceutical compounds in wastewater. Research on glutaraldehyde crosslinked alginate-chitosan nanoparticles as paracetamol adsorbent has been carried out. This research used the ionic gelation method. Nanoparticles were characterized using transmission electron microscopy (TEM), scanning electron microscope (SEM-EDX) and Fourier transform infra-red spectrophotometer (FTIR). Furthermore, the nanoparticles were used for paracetamol adsorption. The results showed that the form nanoparticles are coarse solid powder and brownish yellow. The TEM image shows an average nanoparticle size of 8.22 nm. Glutaraldehyde crosslinked alginate-chitosan nanoparticles adsorbed paracetamol with adsorption kinetics followed a pseudo-second-order or Ho-McKay model, the adsorption rate constant of 0.0324 g mg−1 min−1. The isotherm study of paracetamol adsorption by glutaraldehyde cross-linked alginate-chitosan nanoparticles followed the isotherm Dubinin-Radushkevich isotherm model with a free energy value of 707.1068 kJ mol−1, and this value indicates the adsorption process by chemically or chemisorption