Adhitasari Suratman
Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, Sekip Utara, Yogyakarta 55281, Indonesia

Published : 7 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 7 Documents
Search

Effect of Reducing Agents on Physical and Chemical Properties of Silver Nanoparticles Roto Roto; Hani Prima Rasydta; Adhitasari Suratman; Nurul Hidayat Aprilita
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.
Antifungal Activity of TiO2/Ag Nanoparticles under Visible Light Irradiation Nahzim Rahmat; Endang Tri Wahyuni; Adhitasari Suratman
Indonesian Journal of Chemistry Vol 21, No 1 (2021)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.49150

Abstract

The doping of TiO2 by Ag(I) from [Ag(S2O3)2]3– contained in radiophotography wastewater by photoreduction method has been performed. TiO2/AgNPs photocatalyst was examined for its activity as an antifungal material for the inhibition of C. albicans in water under visible light irradiation. In the doping process, the weight of TiO2 was varied to obtain TiO2/AgNPs with different amounts of Ag. The TiO2/AgNPs samples were characterized by using FTIR, SRUV, TEM, SEM-EDX, and XRD methods. The antifungal test was carried out by disc diffusion method under visible light irradiation, wherein the amount of Ag-doped on TiO2, the dose of TiO2/AgNPs, and the irradiation time were optimized. The research results indicated that the antifungal activity of TiO2/AgNPs in inhibiting C. albicans has been successfully prepared. The highest inhibition was achieved by using 0.5 g/L of TiO2/AgNPs (I), at 5 h of irradiation time.
Controlled Release Fertilizer Encapsulated by Glutaraldehyde-Crosslinked Chitosan Using Freeze-Drying Method Adhitasari Suratman; Dwi Ratih Purwaningsih; Eko Sri Kunarti; Agus Kuncaka
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.55133

Abstract

A new encapsulation of NPK fertilizer hydrogel granules made from glutaraldehyde crosslinked chitosan has been successfully fabricated. This designed fertilizer was aimed to maximize the fertilizing process in the soil, as the environmental pollution affected by the excess release of the nutrients can be prevented. The granule was prepared from biodegradable chitosan crosslinked with glutaraldehyde by applying a method of air and freeze-drying. The release test proved that this designed fertilizer showed a good performance as a Controlled Release Fertilizer (CRF) in which the hydrogel granules could absorb and deposit large amounts of NPK. Later on, they could also release large amounts of NPK as well, unlike several types of CRFs. The release percentage of NPK out of the granules tended to decrease with an increase of pH at a range close to the average pH of the soil, which is neutral to base. Comparing two methods, the freeze-drying technique, which yields a bigger pore size, showed a higher release percentage than air-drying. The release kinetics of the granules followed the Korsmeyer-Peppas model.
Analysis and Characterization of Solid and Liquid Organic Fertilizer from Hydrothermal Carbonization (HTC) of Chicken Feather and Blood Waste Agus Kuncaka; Rizky Ibnufaatih Arvianto; Almas Shafira Ramadhanty Bunga Latifa; Munawir Ramadhan Rambe; Adhitasari Suratman; Sugeng Triono
Indonesian Journal of Chemistry Vol 21, No 3 (2021)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.59353

Abstract

Conversion of feather and blood from chicken slaughterhouse waste for producing solid and liquid organic fertilizer excluding composting process with a variation of the mass ratio of feather and blood of a chicken has been conducted. The nitrogen, sulfur, and iron content in the solid and liquid product of the hydrothermal carbonization process were analyzed to identify and characterize the possibility of hydrolysate as a source of nitrogen, sulfur, and iron in soil fertilizer. Feather and blood of chicken waste were introduced to a hydrothermal carbonization reactor with the addition of limestone at a temperature range of 160–170 °C for the preparation of solid and liquid organic fertilizer. According to the FTIR interpretation, the solid product had functional groups such as NH, OH, CH sp3, SH, C=O, C=C, C–O–C, and C–H aromatic. The nitrogen, sulfur, and iron content of the optimal ratio in the solid phase were 4.67%, 1.63%, and 3694.56 ppm, while their contents in the liquid fertilizer were 3.76%, 1.80%, and 221.56 ppm, respectively. The vibration of 478 cm–1 is attributed to Fe–O paramagnetic (Fe2O3) confirmed by TEM images showed the diameter size less than 20 nm indicating the presence of superparamagnetic material.
Fabrication of Alginate-Based Electrospun Nanofibers for Carbon Dioxide Removal Adhitasari Suratman; Desi Nur Astuti; Ryan Jonathan; Agus Kuncaka; Yusril Yusuf
Indonesian Journal of Chemistry Vol 22, No 2 (2022)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.67349

Abstract

A fabrication of eco-friendly and low-cost adsorbent materials is reported for CO2 removal. Alginate nanofibers (NFs) adsorbents were prepared by incorporating poly(vinyl alcohol) (PVA) into alginate solutions via electrospinning technique from alginate biopolymers. Smooth-surfaced Alg/PVA NFs were obtained with a specific surface area of 9.197 m2 g–1. Zeolite (Z) was impregnated into polymer solutions to enhance the properties and performances of alginate nanofibers. Alg/PVA/Z NFs appeared to be rougher with a specific surface area of 25.998 m2 g–1. Both adsorbents offered great potential for CO2 adsorbent in the future. The adsorption isotherms of Alg/PVA NFs followed the Langmuir model with optimum CO2 adsorption capacity of 3.286 mmol g–1 and  Alg/PVA/Z NFs followed Dubinin-Radushkevich model with optimum CO2 adsorption capacity of 10.710 mmol g–1.
Enhancing the Amino Acid and Reducing the Metal Ions Contents in the Hydrolysate Resulting from Hydrothermal Carbonization of Chicken Feather Waste by Chemical Phosphorylation Agus Kuncaka; Wahyu Tri Supardi; Winarto Haryadi; Adhitasari Suratman; Priatmoko Priatmoko
Indonesian Journal of Chemistry Vol 23, No 1 (2023)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.73725

Abstract

Chemical phosphorylation of hydrolysate resulting from hydrothermal carbonization of chicken feather waste was performed to enhance the amino acids and reduce the metal ions content. The aim of this research is to improve the functional properties of chicken feathers hydrolysate without impairing the nutritional availability thereof with the cheapest chemical method by phosphorylation. Phosphorylated hydrolysate can function as animal feed and fertilizer. The hydrolysate of chicken feathers was obtained by hydrothermal carbonization in an alkaline condition using a CaO and KOH catalyst, by the ratio of water:dry matter of chicken feathers is 5:1, at 9–10 atm pressure, and in a temperature of 190–200 °C during 3 h. Phosphorylation has been carried out by reacting the hydrolysate with H3PO4 85% in pH of 5, 6, 7 and using the original hydrolysate as control. The sample that has been prepared was characterized and semi-quantitative analyzed by HPLC and AAS. The phosphorylation results showed that the total maximum protein of soluble protein, their minimum metal ions, and anion in soluble protein was obtained at pH 7, while the higher the pH, the lower the liquid protein that was obtained.
Glutaraldehyde Crosslinked Alginate-Chitosan Nanoparticles as Paracetamol Adsorbent Nurmala Nurmala; Adhitasari Suratman; Suherman Suherman
Indonesian Journal of Chemistry Vol 23, No 6 (2023)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.82431

Abstract

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.