Saharman Gea

Dr. Saharman Gea

orcid

Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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17 April 2023 in ACS Omega
Verified
Journal Article
Open access
DADinda Gusti Ayu
Dinda Gusti Ayu
SGSaharman Gea
Saharman Gea
ANAndriayani
Andriayani
DTDewi Junita Telaumbanua
Dewi Junita Telaumbanua
APAverroes Fazlur Rahman Piliang
Averroes Fazlur Rahman Piliang
ATAlfred Tok
Alfred Tok

1 January 2023 in International Journal of Biological Macromolecules
Verified
Journal Article
Closed access
KPKhatarina Meldawati Pasaribu
Khatarina Meldawati Pasaribu
SISyafruddin Ilyas
Syafruddin Ilyas
TTTamrin Tamrin
Tamrin Tamrin
Iza RadeckaIza Radecka
Iza Radecka
Sam SwinglerSam Swingler
Sam Swingler
SGSaharman Gea
Saharman Gea

3 November 2020 in Biomolecules
Verified
Journal Article
Open access
PDF file
KPKhatarina Meldawati Pasaribu
Khatarina Meldawati Pasaribu
SGSaharman Gea
Saharman Gea
SISyafruddin Ilyas
Syafruddin Ilyas
TTTamrin Tamrin
Tamrin Tamrin
Iza RadeckaIza Radecka
Iza Radecka
Bacterial cellulose (BC), chitosan (Chi), and collagen (Col) are known as biopolymers which have met some properties that are required as wound dressing. This study focused on investigating the fabrication of BC-based wound dressing with chitosan and collagen, since chitosan has red blood cells binding and anti-bacterial properties, while collagen can support cell and tissue growth for skin wounds. The BC-based wound dressing was prepared by impregnating BC fibers in the chitosan and/or collagen solution for 24 h. FTIR was used to confirm the intermolecular interaction of amine and hydroxyl group of chitosan and/or collagen in BC-based wound dressing. Furthermore, the XRD diffractogram of the wound dressing show broader peaks at 14.2°, 16.6°, and 22.4° due to the presence of chitosan and collagen molecules in BC fibers. These results were then supported by SEM images which confirmed that chitosan and collagen were well penetrated into BC fibers. TGA curves revealed that BC/Chi/Col has better thermal properties based on the Tmax compare to BC/Col/Chi. Feasibility of the mats to be applied as wound dressing was also supported by other tests, i.e., water content, porosity, and hemocompatibility, which indicates that the wound dressing is classified as nonhemolytic materials. However, BC/Col/Chi was considered a more potential wound dressing to be applied compared to BC/Chi/Col since it has larger pores and showed better antibacterial properties (larger zones of inhibition) against S. aureus and E. coli via disk diffusion tests.

15 May 2020 in Materials
Verified
Journal Article
Open access
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SGSaharman Gea
Saharman Gea
ASAmir Hamzah Siregar
Amir Hamzah Siregar
EZEmma Zaidar
Emma Zaidar
MHMahyuni Harahap
Mahyuni Harahap
DIDenny Pratama Indrawan
Denny Pratama Indrawan
YPYurika Almanda Perangin-Angin
Yurika Almanda Perangin-Angin
A study on isolation and characterisation of cellulose nanofibre (CNF) and lignin was conducted to expand the application of CNF and lignin from oil palm biomass. CNF was extracted by steam explosion and the by-product was precipitated to obtain lignin by using the soda-pulping method. The concentrations of NaOH used for CNF by-product precipitation were 2%, 4%, and 6%. The morphology of CNF and lignin was characterised using scanning electron microscopy (SEM). The nanofibre of CNF with dimension between 50 nm and 100 nm was investigated using transmission electron microscopy (TEM). The functional group was observed using Fourier-transform infrared (FTIR) spectroscopy, showing that CNF had the structure of cellulose-I. In addition, the chemical structures of isolated and commercial lignin were analysed using 1H-NMR spectrometry. CNF had a 72% crystallinity index characterised by X-ray diffraction (XRD), while lignin showed an amorphous form. The characterisation of isolated lignin was compared with commercial lignin. The two lignins had similar particle size distribution from 1 to 100 μm. From UV-visible analysis, the lignin had aromatic rings/non-conjugated phenolic groups. The morphology of isolated lignin was rough and flaky. Commercial lignin was in powder form with near-spherical morphology. Thermogravimetric analysis (TGA) of CNF showed 30% of residue at 600 °C. The results showed a simple method to isolate CNF and lignin from oil palm empty fruit bunches.

9 June 2022 in Journal of Materials Research and Technology
Verified
Journal Article
Open access
SGSaharman Gea
Saharman Gea
SSSuhut A. Situmorang
Suhut A. Situmorang
NPNurhaida Pasaribu
Nurhaida Pasaribu
APAverroes F.R. Piliang
Averroes F.R. Piliang
BABoy Attaurrazaq
Boy Attaurrazaq
SGstergios goutianos
stergios goutianos

15 January 2020 in Catalysts
Verified
Journal Article
Open access
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JSJunifa Layla Sihombing
Junifa Layla Sihombing
SGSaharman Gea
Saharman Gea
BWBasuki Wirjosentono
Basuki Wirjosentono
HAHarry Agusnar
Harry Agusnar
APAhmad Nasir Pulungan
Ahmad Nasir Pulungan
YHYasir Arafat Hutapea
Yasir Arafat Hutapea
This research was aimed to investigate the effect of Co and Co-Mo metal loaded on Sarulla Natural Zeolite which has been activated and calcined (SNZ-Cal) as supports for better understanding of characterization and catalytic activity on hydrocracking of MEFA rubber seed oil. The Co and Co-Mo metal was added through a wet impregnation method using Co(NO3)2·6H2O and (NH4)·6Mo7O24·4H2O precursor salts. The catalyst was oxidized at 500 °C for 2 h within oxygen gas flow, followed by a reduction process with H2 gas flow with similar condition to obtain the catalysts. Based on the result, it was found that the resulted catalysts displayed an increase in crystal grain size compared to the metal-free catalyst. Particularly, catalyst that was impregnated with Co metal has a larger surface area and pore diameter and smaller pore volume than Co-Mo metal impregnated to the catalyst. In fact, it was revealed that this catalyst possessed the highest catalytic activity and selectivity. Furthermore, the resulting gas products reached 64 wt.% and the distribution of biogasoline fraction of hydrocarbons (C6-C12) amounted to 83.19 wt.%.