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Investigation of Chlorophyl-a Derived Compounds as Photosensitizer for Photodynamic Inactivation Listiana Oktavia; Irma Mulyani; Veinardi Suendo
Bulletin of Chemical Reaction Engineering & Catalysis 2021: BCREC Volume 16 Issue 1 Year 2021 (March 2021)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.16.1.10314.161-169

Abstract

Chlorophyll has unique physicochemical properties which makes them good as photosensitizer of Photodynamic Inactivation (PDI). The physicochemical properties of chlorophyll as photosensitizer can be optimized through several routes.  One of the possible route is by replacing the metal ion center of chlorophyll with other ions. In this research, the effect of coordinated metal ion in the natural chlorophyll-a was studied for bacterial growth (S. aureus) inhibition. The replacement of metal in the center of chlorophyll hopefully can improve the intensity of Intersystem Crossing Mechanism (ISC) lead to the formation of singlet oxygen species. The chlorophyll a and b were isolated from spinach via precipitation technique using 1,4 dioxane and water. The chlorophyll a and b were separated using sucrose column chromatography. The thin layer chromatography result showed that chlorophyll a (Rf: 0.57) had been well separated with chlorophyll b (Rf: 0.408). The absorption spectra of chlorophyll a and b showed that the Soret band was observed at 411 and 425 nm, while the Q band appeared at 663 and 659 nm. Replacement of metal ion center shifted the Soret band of chlorophyll- a derivatives to lower energy region, while Q-band was slightly shifted to the higher energy region. The absorption and the fluorescence intensity were  also observed decreasing after ion replacement. The Inhibition activity investigation over S. aureus showed the highest inhibition activity was exhibited by Zn-pheophytin-a (66.8%) followed by chlorophyll a (30.1 %) and Cu-pheophytin-a (0%). The inhibition activity is correlated with decreasing fluorescence intensity. The formation of singlet oxygen by ISC mechanism is hypothesized to deactivate the excitation state of Cu-pheophytin-a. 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). 
Synthesis of Spherical Nanostructured g-Al2O3 Particles using Cetyltrimethylammonium Bromide (CTAB) Reverse Micelle Templating Didi Prasetyo Benu; Veinardi Suendo; Rino Rakhmata Mukti; Erna Febriyanti; Fry Voni Steky; Damar Rastri Adhika; Viny Veronika Tanuwijaya; Ashari Budi Nugraha
Bulletin of Chemical Reaction Engineering & Catalysis 2019: BCREC Volume 14 Issue 3 Year 2019 (December 2019)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.14.3.3855.542-550

Abstract

We demonstrated the synthesis of spherical nanostructured g-Al2O3 using reverse micelle templating to enhance the surface area and reactant accessibility. Three different surfactants were used in this study: benzalkonium chloride (BZK), sodium dodecyl sulfate (SDS) and cetyltrimethylammonium bromide (CTAB). We obtained spherical nanostructured particles only using CTAB that form a reverse micelle emulsion. The particles have wide size distribution with an average size of 2.54 mm. The spherical particles consist of nanoplate crystallites with size 20-40 nm randomly arranged forming intercrystallite spaces. The crystalline phase of as-synthesized and calcined particles was boehmite and g-Al2O3, respectively as determined by XRD analysis. Here, the preserved particle morphology during boehmite to g-Al2O3 transformation opens a facile route to synthesize g-Al2O3 particles with complex morphology. The specific surface area of synthesized particles is 201 m2/g, which is around five times higher than the conventional g-Al2O3 (Aldrich 544833). Spherical nanostructured g-Al2O3 provides wide potential applications in catalysis due to its high density closed packed structure, large surface area, and high accessibility. 
Preparation of Polyaniline Emeraldine Salt for Conducting-Polymer-Activated Counter Electrode in Dye Sensitized Solar Cell (DSSC) using Rapid-Mixing Polymerization at Various Temperature Auliya Nur Amalina; Veinardi Suendo; Muhammad Reza; Phutri Milana; Risa Rahmawati Sunarya; Damar Rastri Adhika; Viny Veronika Tanuwijaya
Bulletin of Chemical Reaction Engineering & Catalysis 2019: BCREC Volume 14 Issue 3 Year 2019 (December 2019)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.14.3.3854.521-528

Abstract

Polyaniline Emeraldine Salt (PANI ES) as a conductive polymer has been used as a Pt-free counter electrode materials in DSSC. In this study, polymerization temperature was varied at relatively high temperature from 308 to 348 K with respect to the standard low polymerization temperature at 273 K. The synthesis held in varied high-temperature to study the effect of synthesis condition resulted to the performance as counter electrode in DSSC. The effect of high-temperature synthesis condition gives interesting results, the FTIR-ATR spectra show the presence of vibrational modes of phenazine structure obtained at high polymerization temperature, indicate the changing in the chain geometry. Raman Spectroscopy shows the decrease of the I1194/I1623 intensity ratio that can be interpreted that the degree-of-freedom of C-H bond bending mode decreases in the benzenoid ring, while the stretching mode degree-of-freedom along the chain is preserved or increased. The electrical conductivity profile has changed from metal-like at low-temperature into a semiconductor-like profile at high-temperature. Scanning Electron Microscope images reveals that a change in the morphology of PANI ES with temperature. At low-temperature (273 K) the morphology has a globular shape, while at high-temperature it tends to form nanorod structure. DSSC device with highest efficiency is attained for PANI ES polymerized at 273 K (1.91%) due to its high conductivity. The lowest efficiency is observed in device using PANI ES synthesized at 328 K (1.15%) due to its low conductivity due to the formation of phenazine structure. 
bcl Morphology Formation Strategy on Nanostructured Titania via Alkaline Hydrothermal Treatment Fry Voni Steky; Veinardi Suendo; Rino Rakhmata Mukti; Didi Prasetyo Benu; Muhammad Reza; Damar Rastri Adhika; Viny Veronika Tanuwijaya; Ashari Budi Nugraha
Bulletin of Chemical Reaction Engineering & Catalysis 2019: BCREC Volume 14 Issue 3 Year 2019 (December 2019)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.14.3.3853.513-520

Abstract

Titanium dioxide (TiO2) is a semiconductor material that plays an important role in photocatalysis. Bicontinuous concentric lamellar (bcl) is an interesting morphology with an open channel pore structure that has been successfully synthesized on silica-based materials. If bcl morphology can be applied in TiO2 system, then many surface properties of TiO2 can be enhanced, i.e. photocatalytic activity. A simple and effective strategy has been demonstrated to transform aggregated and spherical TiO2 particles to bcl morphology via alkaline hydrothermal route. Alkaline hydrothermal treatment successfully transforms TiO2 particle surface to have bcl morphology through swelling with ammonia then followed by phase segregation process. We proposed this strategy as a general pathway to transform the particle surface with any shape to have bcl morphology. 
Pengaruh Variasi Dopan Asam Terhadap Kinerja Baterai Sekunder Polianilina|Zn Akbar, Said Ali; Suendo, Veinardi; Rochliadi, Achmad
CHEESA: Chemical Engineering Research Articles Vol. 3 No. 1 (2020)
Publisher : Universitas PGRI Madiun

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (498.282 KB) | DOI: 10.25273/cheesa.v3i1.6702

Abstract

Studi tentang baterai sekunder polianilina(PAni)|Zn telah banyak dikembangkan, tetapi sejauh ini masih belum ada penjelasan mengenai pengaruh asam terhadap kinerja baterai tersebut. PAni disitensis menggunakan metoda elektrodeposisi dengan tegangan 0,7 V selama 30 menit. PAni hasil sintesis dikarakterisasi menggunakan Voltammetri dan Spektroskopi Inframerah. Baterai PAni|Zn didesain dalam bentuk sandwich, kemudian pengukuran kinerja digunakan impedansi serta pengisian-pengosongan. Baterai dengan elektroda PAni-Cl dan PAni-Br mempunyai kinerja yang lebih baik dengan specific capacity saat ke-60 yaitu 55,4 dan 37,4 mAh g-1. Pengukuran impedansi pada baterai dengan elektroda PAni-Cl, PAni-Br, dan PAni HClO4, menunjukan resistance solution (Rs) secara berurutan yaitu 1,38; 2,56; dan 3,03 W dan resistance charge transfer (Rct) 2,24; 2,97; dan 7,71 W. Oleh sebab itu, baterai PAni|Zn dengan dopan HCl menunjukkan kinerja terbaik dibanding dengan asam yang lain.