Hermawan Judawisastra - Academia.edu (original) (raw)
Papers by Hermawan Judawisastra
Journal of Mathematical and Fundamental Sciences
This study aimed to determine the characteristics of scaffolds made of fibroin from Bombyx mori a... more This study aimed to determine the characteristics of scaffolds made of fibroin from Bombyx mori and spidroin from Argiope appensa in supporting the attachment and proliferation of HDF cells on the scaffolds. Thin-film scaffolds were made using the solvent casting technique, where the scaffold is an amalgamation of fibroin, spidroin, PVA, and glycerol. HDF cells were grown on DMEM medium with 10% FBS and 1% antibiotic-antimicotic. Characterization of the scaffolds was performed by using ATR-FTIR, swelling test, contact angle measurement, tensile test, biodegradation, MTT and SEM. The results of the ATR-FTIR analysis showed that the scaffolds contained fibroin, spidroin, PVA, and glycerol. Swelling and contact angle tests showed that all scaffold combinations were hydrophilic. Mechanical properties and in vitro biodegradation tests showed no significant difference among the scaffold combinations. MTT testing showed that all scaffolds could facilitate the attachment of fibroblasts and ...
Scientific Reports
In this research, hWJ-MSCs were grown on silk scaffolds and induced towards chondrogenesis by sup... more In this research, hWJ-MSCs were grown on silk scaffolds and induced towards chondrogenesis by supplementation with L-ascorbic acid (LAA) or platelet rich plasma (PRP). Silk scaffolds were fabricated with salt leaching method by mixing silk fibroin (SF) with silk spidroin (SS). The silk fibroin was obtained from Bombyx mori cocoon that had been degummed, and the silk spidroin was obtained from wild-type spider Argiope appensa. The effect of scaffold composition and inducer on cell proliferation was observed through MTT assay. The most optimal treatment then continued to be used to induce hWJ-MSC towards chondrogenic differentiation for 7 and 21 days. Scaffolds characterization showed that the scaffolds produced had 3D structure with interconnected pores, and all were biocompatible with hWJ-MSCs. Scaffold with the addition of 10% SS + 90% SF showed higher compressive strength and better pore interconnectivity in comparison to 100% silk fibroin scaffold. After 48 h, cells seeded on sca...
Jurnal Teknologi Bahan dan Barang Teknik, Dec 31, 2013
Keunggulan VARI dibanding hand lay-up tingginya fraksi volume serat, fraksi volume void yang rend... more Keunggulan VARI dibanding hand lay-up tingginya fraksi volume serat, fraksi volume void yang rendah dan kondisi manufaktur FRP yang ramah lingkungan. Kualitas produk VARI ditentukan oleh banyak parameter sehingga optimasinya memerlukan banyak trial dan sampel. Penelitian ini memakai metoda Taguchi dengan hanya melakukan delapan run kombinasi serat penguat plain weave dan matrix polyester resin. Parameter infusi yang dioptimasi meliputi bentuk penampang inlet, aplikasi tekanan, gravitasi, dan media distribusi, kandungan katalis dan solvent. Prosedur penelitian dilakukan menggunakan standar ASTM D-2854, software image pro analysis, serta pengukuran variasi tebal dan cacat permukaan sampel. Hasil optimasi Taguchi telah mencapai kriteria the greaterthe better dan the lower-the better dalam bentuk fisik masing-masing berupa peningkatan fraksi volume serat dan penurunan fraksi volume void, cacat permukaan, variasi tebal, serta racetracking. Kombinasi parameter optimum yang dicapai adalah tekanan linier, penggunaan distribusi media chop strand mat, aplikasi penampang spiral, beda tinggi 15 cm antara permukaan cetakan dan permukaan resin, pemakaian 0,5% berat methyl ethyl ketone peroxide, dan 5% berat solven aseton.
Journal of Mathematical and Fundamental Sciences
Skin tissue engineering is a developing technology to heal severe wounds. Combining polyvinyl alc... more Skin tissue engineering is a developing technology to heal severe wounds. Combining polyvinyl alcohol (PVA) and silk fibroin (SF) nanofibers is a promising method of developing a skin scaffold because the resulting structure mimics collagen fibers. The aim of this research was to study the growth of human dermal fibroblasts (HDF) on a polyvinyl alcohol-silk fibroin (PVA-SF) nanofiber scaffold that was produced by electrospinning. Morphological characterization and chemical analysis of the scaffold were performed by scanning electron microscopy (SEM), Fourier transform infrared spectrophotometry (FTIR), and contact angle measurement. The biocompatibility of the scaffold was tested by MTT cytotoxicity assay, SEM analysis, adherence ratio calculation, and analysis of the HDF growth curve for 9 days. The FTIR results confirmed the presence of SF and PVA. The average fiber diameter and pore size of the PVA scaffold were greater than those of the PVA-SF scaffold. Both scaffolds had hydrophilic properties and were not cytotoxic. Thus, HDF can attach and grow on both types of scaffold better than HDF seeded on a polystyrene plate. In conclusion, the addition of SF to the PVA nanofibers caused bead formation, which affected the substrate topography, decreased hydrophilicity and also decreased the fiber diameter and pore size in the nanofiber scaffold compared to the PVA nanofiber scaffold without SF addition. SF addition increases cell attachment to the nanofiber scaffold and has potential to facilitate HDF cell growth.
Jurnal Teknologi Bahan dan Barang Teknik
Modulus elastisitas merupakan sifat mekanik yang penting dari logam karena dipakai dalam proses d... more Modulus elastisitas merupakan sifat mekanik yang penting dari logam karena dipakai dalam proses desain suatu komponen, yaitu dalam hal analisis tegangan berupa penentuan distribusi tegangan, gaya reaksi, defleksi, dan faktor keamanan. Pengujian tidak merusak dipilih oleh industri karena faktor efisiensi dan efektivitasnya. Salah satu metode pengujian tidak merusak ialah ultrasonik. Pengukuran kecepatan gelombang ultrasonik yang merambat dalam medium suatu material digunakan sebagai dasar untuk mengevaluasi. Kecepatan gelombang ultrasonik tergantung pada densitas dan sifat elastik, yaitu modulus elastisitas dan Poisson's ratio. Metode ultrasonik yang sering digunakan, yaitu transmisi dan pulsa-gema. Pulsa-gema lebih mudah digunakan dan hanya membutuhkan satu sisi material. Penelitian ini bertujuan untuk menentukan modulus elastisitas logam, yakni baja dan aluminium berdasarkan pengukuran kecepatan gelombang longitudinal dengan teknik pulsa-gema. Pengujian dilakukan menggunakan tiga probe lurus yang memiliki frekuensi (1, 2, 4 MHz) dan diameter yang berbeda. Dua metode pengukuran kecepatan yang digunakan adalah 2 Point (2P) dan Multiple Backwall Echoes (MBE). Modulus elastisitas berhasil ditentukan dengan galat antara 0,05% − 6,23% untuk baja dan aluminium di kisaran 0,17%-6,53%. Probe berfrekuensi 4 MHz dan metode 2P menghasilkan galat terkecil, yaitu 0,05% untuk baja serta probe berfrekuensi 1 MHz dan metode MBE memberikan galat terkecil, yaitu 0,17% untuk aluminium.
THE 4TH BIOMEDICAL ENGINEERING’S RECENT PROGRESS IN BIOMATERIALS, DRUGS DEVELOPMENT, HEALTH, AND MEDICAL DEVICES: Proceedings of the International Symposium of Biomedical Engineering (ISBE) 2019
Degenerative diseases due to damaged articular cartilage in the hip, knee, and other body parts r... more Degenerative diseases due to damaged articular cartilage in the hip, knee, and other body parts require suitable materials for repairing damaged tissue application. Therefore, the regenerative technology involving tissue engineering is needed as one of the available alternatives. Tissue engineering generally develops stem cells or adult tissue cells as a source of cells. Stem cells can be seeded in a scaffold, which is a supporting material during cell regeneration process until new tissue is formed. One of the most readily available sources of multipotent stem cell is from human Wharton's jelly (Wharton's jelly derived Mesenchymal Stem Cells / hWJ-MSCs) which can be induced to chondrocytes. Protein-based scaffolds such as fibroin (SF) from silkworms (Bombyx mori) and spidroin (SS) from spiders (Argiope sp.) can be developed and applied to repair damaged tissues since the materials are biodegradable and also biocompatible. Biocompatibility test showed that the scaffolds made SF mixed with SS were not toxic to hWJ-MSCs. Scaffold with SS 10% mixed with SF 90% is able to support cell proliferation better than silk fibroin scaffold 100%. The supplementation of Platelet Rich Plasma (PRP) and ascorbic acid (LAA) on hWJ-MSCs were able to increase cell proliferation ability, which is one of important steps in chondrogenic differentiation. PRP with a concentration of 10% (v/v) and LAA with a concentration of 50 μg/ml can increase cell proliferation rate better than other concentration variations. Cell attachment through vinculin expression observed with Immunocytochemistry (ICC) method, the results show that in 12, 24 and 48 hours cell attachment to scaffold with spidroin fiber 10% + fibroin fiber 90% increased significantly compared to 100% fibroin scaffold.
IOP Conference Series: Materials Science and Engineering
Natural fiber application due to its competitiveness attracted many research in green composites.... more Natural fiber application due to its competitiveness attracted many research in green composites. However, the tensile properties of natural fiber composites might be influenced by several factors such as treatment of the fibers, manufacturing processes, and water absorption levels. In this research, we use petung bamboo fibers as natural fibers candidate for a good reinforcement in green composites. The study focused on the tensile property of bamboo fiber reinforced epoxy composites due to alkali treatment, manufacturing process, and water absorption. The composites were made with three variations: the fibers were varied without and with alkaline treatment (5% NaOH); manual lay-up method and hot press were applied as manufacturing variation; moisture content in the composites was varied in dry condition and after water absorption treatment. Tensile testing and Scanning Electron Microscope (SEM), were performed to improve tensile strength of composite and fiber-matrix interface quality. The alkali treatment has less effect to the tensile strength than of the volume fraction gain and the void content. Composite manufacturing by hot press has a significant effect to the improvement of tensile strength up to 37% compare to the hand lay-up method. Water absorption up to 8.8% had decreased the tensile strength of composites up to 29%. The alkali treatment on the bamboo fibers had effectively reduced water absorption into the composite as well as the tensile strength reduction.
International Journal on Advanced Science, Engineering and Information Technology
Autologous transplantations, the gold standard, did not meet sufficient health tissue coverage ar... more Autologous transplantations, the gold standard, did not meet sufficient health tissue coverage area for cartilage damage treatments. The field of tissue engineering offers a promising alternative to fulfill this limitation by growing patient own cells on biomaterials through tissue culture, reconstructed into new cartilage tissue, and the implanted to the injury area. To support tissue regeneration, biocompatible, biodegradable, and high strength silk fibroin (SF) was proposed in this study as scaffold materials. In this research, direct dissolution in CaCl 2 /formic acid, a faster and simpler process than traditional dissolution techniques, combined with salt leaching technique. SF contents on the scaffold were varied from 2 w/v% to 12 w/v% and NaCl size as porogen was fixed in diameter of 250±58 µm. Evaluation of the SF scaffold's morphology, hydrophilicity, biodegradability, and biocompatibility were conducted. The results showed porous silk fibroin scaffold had been successfully developed. The SF scaffolds have pore size 261-293 µm with highly interconnected pores. FTIR and XRD analysis of the scaffolds showed the characteristics of silk fibroin, which reveals the α-helix amorphous and β-sheet crystalline structure and comparable to the silk fibers. The scaffold showed good hydrophilicity and high water uptakes, which essential properties for cell survival. The scaffold degraded under Protease XIV, indicate biodegradable properties. Observation of cell attachment confirms the scaffold has good biocompatibility to adipose-derived stem cells and are suitable to be used in cartilage tissue engineering.
Articular cartilage is an avascular tissue with limited regenerative property. Therefore, a defec... more Articular cartilage is an avascular tissue with limited regenerative property. Therefore, a defect or trauma in articular cartilage due to disease or accident can lead to progressive tissue deterioration. Cartilage tissue engineering, by replacing defective cartilage tissue, is a method for repairing such a problem. In this research, three main aspects-cell, biomaterial scaffold, and bioactive factors-that support tissue engineering study were optimized. Adipose-derived mesenchymal stem cells (ADSC) that become cartilage were grown in an optimized growth medium supplemented with either platelet rich plasma (PRP) or L-ascorbic acid (LAA). As the characterization result, the ADSC used in this experiment could be classified as Mesenchymal Stem Cell (MSC) based on multipotency analysis and cell surface marker analysis. The biomaterial scaffold was fabricated from the Bombyx morii cocoon using silk fibroin by salt leaching method and was engineered to form different sizes of pores to provide optimized support for cell adhesion and growth. Biocompatibility and cytotoxicity evaluation was done using MTT assay to optimize silk fibroin concentration and pore size. Characterized ADSC were grown on the optimized scaffold. LAA and PRP were chosen as bioactive factors to induce ADSC differentiation to become chondrocytes. The concentration optimization of LAA and PRP was analyzed by cell proliferation using MTT assay and chondrogenic differentiation by measuring glycosaminoglycan (GAG) using Alcian Blue at 605 nm wavelength. The optimum silk fibroin concentration, pore size, LAA concentration, and PRP concentration were used to grow and differentiate characterized ADSC for 7, 14, and 21 days. The cell morphology on the scaffold was analyzed using a scanning electron microscope (SEM). The result showed that the ADSC could adhere on plastic, express specific cell surface markers (CD73, CD90, and CD105), and could be differentiated into three types of mature cells. The silk fibroin scaffold made from 12% w/v concentration formed a 500 µm pore diameter (SEM analysis), and was shown by MTT assay to be biocompatible and to facilitate cell growth. The optimum concentrations of the bioactive factors LAA and PRP were 50 µg/mL and 10%, respectively. GAG analysis with Alcian Blue staining suggested that PRP induction medium and LAA induction medium on 12% w/v scaffold could effectively promote not only cell adhesion and cell How to cite this article Barlian A, Judawisastra H, Alfarafisa NM, Wibowo UA, Rosadi I. 2018. Chondrogenic differentiation of adipose-derived mesenchymal stem cells induced by L-ascorbic acid and platelet rich plasma on silk fibroin scaffold. PeerJ 6:e5809 http://doi.org/10.7717/peerj.5809 proliferation but also chondrogenic differentiation of ADSC within 21 days of culture. Therefore, this study provides a new approach to articular tissue engineering with a combination of ADSC as cell source, LAA and PRP as bioactive factors, and silk fibroin as a biocompatible and biodegradable scaffold.
JURNAL SELULOSA
The alkalized of petung bamboo fiber (Dendrocalamus asper) as reinforcement of polymer compositeP... more The alkalized of petung bamboo fiber (Dendrocalamus asper) as reinforcement of polymer compositePetung bamboo (Dendrocalamus asper) has good fiber characteristic and it has potential to substitute glass fiber as reinforcement in polymeric composite. However, like other natural based materials, bamboo fiber has a high variability in mechanical properties and inherently hygroscopic characteristic. Therefore it is required to optimize the petung bamboo qualities. The fiber optimization was carried out by alkalization process using NaOH solution with varying concentration of 0, 3, 5, and 10% v/v. Bamboo fiber processed in chemomechanical was used in this investigation. Characterization of density, mechanical and chemicals was conducted by pycnometry method, tensile strength testing, Fourier Transform Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). The data variability was analyzed by Weibull distribution. Result indicates that the optimum condition of alkalization process of...
Jurnal Sains Materi Indonesia, 2018
ABSTRAK SIFAT TARIK KOMPOSIT EPOKSI BERPENGUAT SERAT BAMBU AKIBAT PENYERAPAN AIR. Serat bambu mem... more ABSTRAK SIFAT TARIK KOMPOSIT EPOKSI BERPENGUAT SERAT BAMBU AKIBAT PENYERAPAN AIR. Serat bambu memiliki potensi sebagai serat penguat pengganti serat gelas dalam pembuatan komposit polimer, karena sifatnya yang terbaharui dan ramah lingkungan. Namun daya serap air yang tinggi pada serat bambu dapat menurunkan sifat tarik komposit yang dihasilkan. Hal ini akibat memburuknya ikatan antarmuka serat dan matriks. Penelitian ini bertujuan untuk mengkaji degradasi sifat tarik biokomposit epoksi berpenguat serat bambu petung akibat penyerapan air. Biokomposit epoksi berpenguat serat bambu petung dibuat dengan metode tekan panas dengan variasi serat tanpa alkalisasi (0 % NaOH) dan dengan alkalisasi (5 % NaOH). Pengujian biokomposit, dilakukan dengan cara uji air mendidih, uji tarik dan Scanning Electron Microscope (SEM). Kadar penyerapan air biokomposit tanpa alkalisasi lebih tinggi dibandingkan dengan biokomposit yang telah mengalami alkalisasi (5 % NaOH). Penyerapan air mengakibatkan degradasi pada biokomposit dan menurunkan kekuatan tarik biokomposit hingga 23 %. Perlakuan alkali 5 % NaOH, dapat meminimalisir persentase penurunan kekuatan biokomposit, dengan persentase penurunan kekuatan tarik sebesar 17 %. Hasil pemeriksaan pada permukaan patahan menunjang hasil pengujian tarik. Akibat penyerapan air, kekuatan tarik komposit epoksi bambu petung menurun karena sifat serat dan antarmuka serat matriks telah terdegradasi. ABSTRACT TENSILE PROPERTIES DECREMENT OF THE BAMBOO FIBER REINFORCED EPOXY COMPOSITE DUE TO WATER ABSORPTION. Bamboo fiber has potential as reinforcing fibers as subtitute to glass fiber for polymer composites, due to their renewable properties and environmental friendly. However, high water absorption in bamboo fibers, can reduce tensile properties of composites due to poor fiber-matrix interface. This research aims to study degradation of tensile properties of bamboo fiber reinforced epoxy composites caused by water absorption. Bamboo petung fiber reinforced epoxy biocomposites were fabricated by means compression molding method with fiber variations without alkalization (0 %) and with alkalization (5 %). Biocomposite examinations were carried out by means of water boiling test, tensile test and Scanning Electron Microscope (SEM). Water absorption of biocomposite without alkalization is higher than biocomposite with alkalization (5 % NaOH). Water absorption caused degradation on the biocomposites, and decreased the tensile strength up to 23 %. Alkalization 5 % NaOH minimized the percentage reduction of tensile strength with percentage reduction of tensile strength for 17 %. The results of examination on surface fracture support the tensile test results. Water absorption has lowered composite tensile strength due to occurrence of properties degradation on both fiber and fiber-matrix interface.
Journal of Mathematical and Fundamental Sciences
This study aimed to determine the characteristics of scaffolds made of fibroin from Bombyx mori a... more This study aimed to determine the characteristics of scaffolds made of fibroin from Bombyx mori and spidroin from Argiope appensa in supporting the attachment and proliferation of HDF cells on the scaffolds. Thin-film scaffolds were made using the solvent casting technique, where the scaffold is an amalgamation of fibroin, spidroin, PVA, and glycerol. HDF cells were grown on DMEM medium with 10% FBS and 1% antibiotic-antimicotic. Characterization of the scaffolds was performed by using ATR-FTIR, swelling test, contact angle measurement, tensile test, biodegradation, MTT and SEM. The results of the ATR-FTIR analysis showed that the scaffolds contained fibroin, spidroin, PVA, and glycerol. Swelling and contact angle tests showed that all scaffold combinations were hydrophilic. Mechanical properties and in vitro biodegradation tests showed no significant difference among the scaffold combinations. MTT testing showed that all scaffolds could facilitate the attachment of fibroblasts and ...
Scientific Reports
In this research, hWJ-MSCs were grown on silk scaffolds and induced towards chondrogenesis by sup... more In this research, hWJ-MSCs were grown on silk scaffolds and induced towards chondrogenesis by supplementation with L-ascorbic acid (LAA) or platelet rich plasma (PRP). Silk scaffolds were fabricated with salt leaching method by mixing silk fibroin (SF) with silk spidroin (SS). The silk fibroin was obtained from Bombyx mori cocoon that had been degummed, and the silk spidroin was obtained from wild-type spider Argiope appensa. The effect of scaffold composition and inducer on cell proliferation was observed through MTT assay. The most optimal treatment then continued to be used to induce hWJ-MSC towards chondrogenic differentiation for 7 and 21 days. Scaffolds characterization showed that the scaffolds produced had 3D structure with interconnected pores, and all were biocompatible with hWJ-MSCs. Scaffold with the addition of 10% SS + 90% SF showed higher compressive strength and better pore interconnectivity in comparison to 100% silk fibroin scaffold. After 48 h, cells seeded on sca...
Jurnal Teknologi Bahan dan Barang Teknik, Dec 31, 2013
Keunggulan VARI dibanding hand lay-up tingginya fraksi volume serat, fraksi volume void yang rend... more Keunggulan VARI dibanding hand lay-up tingginya fraksi volume serat, fraksi volume void yang rendah dan kondisi manufaktur FRP yang ramah lingkungan. Kualitas produk VARI ditentukan oleh banyak parameter sehingga optimasinya memerlukan banyak trial dan sampel. Penelitian ini memakai metoda Taguchi dengan hanya melakukan delapan run kombinasi serat penguat plain weave dan matrix polyester resin. Parameter infusi yang dioptimasi meliputi bentuk penampang inlet, aplikasi tekanan, gravitasi, dan media distribusi, kandungan katalis dan solvent. Prosedur penelitian dilakukan menggunakan standar ASTM D-2854, software image pro analysis, serta pengukuran variasi tebal dan cacat permukaan sampel. Hasil optimasi Taguchi telah mencapai kriteria the greaterthe better dan the lower-the better dalam bentuk fisik masing-masing berupa peningkatan fraksi volume serat dan penurunan fraksi volume void, cacat permukaan, variasi tebal, serta racetracking. Kombinasi parameter optimum yang dicapai adalah tekanan linier, penggunaan distribusi media chop strand mat, aplikasi penampang spiral, beda tinggi 15 cm antara permukaan cetakan dan permukaan resin, pemakaian 0,5% berat methyl ethyl ketone peroxide, dan 5% berat solven aseton.
Journal of Mathematical and Fundamental Sciences
Skin tissue engineering is a developing technology to heal severe wounds. Combining polyvinyl alc... more Skin tissue engineering is a developing technology to heal severe wounds. Combining polyvinyl alcohol (PVA) and silk fibroin (SF) nanofibers is a promising method of developing a skin scaffold because the resulting structure mimics collagen fibers. The aim of this research was to study the growth of human dermal fibroblasts (HDF) on a polyvinyl alcohol-silk fibroin (PVA-SF) nanofiber scaffold that was produced by electrospinning. Morphological characterization and chemical analysis of the scaffold were performed by scanning electron microscopy (SEM), Fourier transform infrared spectrophotometry (FTIR), and contact angle measurement. The biocompatibility of the scaffold was tested by MTT cytotoxicity assay, SEM analysis, adherence ratio calculation, and analysis of the HDF growth curve for 9 days. The FTIR results confirmed the presence of SF and PVA. The average fiber diameter and pore size of the PVA scaffold were greater than those of the PVA-SF scaffold. Both scaffolds had hydrophilic properties and were not cytotoxic. Thus, HDF can attach and grow on both types of scaffold better than HDF seeded on a polystyrene plate. In conclusion, the addition of SF to the PVA nanofibers caused bead formation, which affected the substrate topography, decreased hydrophilicity and also decreased the fiber diameter and pore size in the nanofiber scaffold compared to the PVA nanofiber scaffold without SF addition. SF addition increases cell attachment to the nanofiber scaffold and has potential to facilitate HDF cell growth.
Jurnal Teknologi Bahan dan Barang Teknik
Modulus elastisitas merupakan sifat mekanik yang penting dari logam karena dipakai dalam proses d... more Modulus elastisitas merupakan sifat mekanik yang penting dari logam karena dipakai dalam proses desain suatu komponen, yaitu dalam hal analisis tegangan berupa penentuan distribusi tegangan, gaya reaksi, defleksi, dan faktor keamanan. Pengujian tidak merusak dipilih oleh industri karena faktor efisiensi dan efektivitasnya. Salah satu metode pengujian tidak merusak ialah ultrasonik. Pengukuran kecepatan gelombang ultrasonik yang merambat dalam medium suatu material digunakan sebagai dasar untuk mengevaluasi. Kecepatan gelombang ultrasonik tergantung pada densitas dan sifat elastik, yaitu modulus elastisitas dan Poisson's ratio. Metode ultrasonik yang sering digunakan, yaitu transmisi dan pulsa-gema. Pulsa-gema lebih mudah digunakan dan hanya membutuhkan satu sisi material. Penelitian ini bertujuan untuk menentukan modulus elastisitas logam, yakni baja dan aluminium berdasarkan pengukuran kecepatan gelombang longitudinal dengan teknik pulsa-gema. Pengujian dilakukan menggunakan tiga probe lurus yang memiliki frekuensi (1, 2, 4 MHz) dan diameter yang berbeda. Dua metode pengukuran kecepatan yang digunakan adalah 2 Point (2P) dan Multiple Backwall Echoes (MBE). Modulus elastisitas berhasil ditentukan dengan galat antara 0,05% − 6,23% untuk baja dan aluminium di kisaran 0,17%-6,53%. Probe berfrekuensi 4 MHz dan metode 2P menghasilkan galat terkecil, yaitu 0,05% untuk baja serta probe berfrekuensi 1 MHz dan metode MBE memberikan galat terkecil, yaitu 0,17% untuk aluminium.
THE 4TH BIOMEDICAL ENGINEERING’S RECENT PROGRESS IN BIOMATERIALS, DRUGS DEVELOPMENT, HEALTH, AND MEDICAL DEVICES: Proceedings of the International Symposium of Biomedical Engineering (ISBE) 2019
Degenerative diseases due to damaged articular cartilage in the hip, knee, and other body parts r... more Degenerative diseases due to damaged articular cartilage in the hip, knee, and other body parts require suitable materials for repairing damaged tissue application. Therefore, the regenerative technology involving tissue engineering is needed as one of the available alternatives. Tissue engineering generally develops stem cells or adult tissue cells as a source of cells. Stem cells can be seeded in a scaffold, which is a supporting material during cell regeneration process until new tissue is formed. One of the most readily available sources of multipotent stem cell is from human Wharton's jelly (Wharton's jelly derived Mesenchymal Stem Cells / hWJ-MSCs) which can be induced to chondrocytes. Protein-based scaffolds such as fibroin (SF) from silkworms (Bombyx mori) and spidroin (SS) from spiders (Argiope sp.) can be developed and applied to repair damaged tissues since the materials are biodegradable and also biocompatible. Biocompatibility test showed that the scaffolds made SF mixed with SS were not toxic to hWJ-MSCs. Scaffold with SS 10% mixed with SF 90% is able to support cell proliferation better than silk fibroin scaffold 100%. The supplementation of Platelet Rich Plasma (PRP) and ascorbic acid (LAA) on hWJ-MSCs were able to increase cell proliferation ability, which is one of important steps in chondrogenic differentiation. PRP with a concentration of 10% (v/v) and LAA with a concentration of 50 μg/ml can increase cell proliferation rate better than other concentration variations. Cell attachment through vinculin expression observed with Immunocytochemistry (ICC) method, the results show that in 12, 24 and 48 hours cell attachment to scaffold with spidroin fiber 10% + fibroin fiber 90% increased significantly compared to 100% fibroin scaffold.
IOP Conference Series: Materials Science and Engineering
Natural fiber application due to its competitiveness attracted many research in green composites.... more Natural fiber application due to its competitiveness attracted many research in green composites. However, the tensile properties of natural fiber composites might be influenced by several factors such as treatment of the fibers, manufacturing processes, and water absorption levels. In this research, we use petung bamboo fibers as natural fibers candidate for a good reinforcement in green composites. The study focused on the tensile property of bamboo fiber reinforced epoxy composites due to alkali treatment, manufacturing process, and water absorption. The composites were made with three variations: the fibers were varied without and with alkaline treatment (5% NaOH); manual lay-up method and hot press were applied as manufacturing variation; moisture content in the composites was varied in dry condition and after water absorption treatment. Tensile testing and Scanning Electron Microscope (SEM), were performed to improve tensile strength of composite and fiber-matrix interface quality. The alkali treatment has less effect to the tensile strength than of the volume fraction gain and the void content. Composite manufacturing by hot press has a significant effect to the improvement of tensile strength up to 37% compare to the hand lay-up method. Water absorption up to 8.8% had decreased the tensile strength of composites up to 29%. The alkali treatment on the bamboo fibers had effectively reduced water absorption into the composite as well as the tensile strength reduction.
International Journal on Advanced Science, Engineering and Information Technology
Autologous transplantations, the gold standard, did not meet sufficient health tissue coverage ar... more Autologous transplantations, the gold standard, did not meet sufficient health tissue coverage area for cartilage damage treatments. The field of tissue engineering offers a promising alternative to fulfill this limitation by growing patient own cells on biomaterials through tissue culture, reconstructed into new cartilage tissue, and the implanted to the injury area. To support tissue regeneration, biocompatible, biodegradable, and high strength silk fibroin (SF) was proposed in this study as scaffold materials. In this research, direct dissolution in CaCl 2 /formic acid, a faster and simpler process than traditional dissolution techniques, combined with salt leaching technique. SF contents on the scaffold were varied from 2 w/v% to 12 w/v% and NaCl size as porogen was fixed in diameter of 250±58 µm. Evaluation of the SF scaffold's morphology, hydrophilicity, biodegradability, and biocompatibility were conducted. The results showed porous silk fibroin scaffold had been successfully developed. The SF scaffolds have pore size 261-293 µm with highly interconnected pores. FTIR and XRD analysis of the scaffolds showed the characteristics of silk fibroin, which reveals the α-helix amorphous and β-sheet crystalline structure and comparable to the silk fibers. The scaffold showed good hydrophilicity and high water uptakes, which essential properties for cell survival. The scaffold degraded under Protease XIV, indicate biodegradable properties. Observation of cell attachment confirms the scaffold has good biocompatibility to adipose-derived stem cells and are suitable to be used in cartilage tissue engineering.
Articular cartilage is an avascular tissue with limited regenerative property. Therefore, a defec... more Articular cartilage is an avascular tissue with limited regenerative property. Therefore, a defect or trauma in articular cartilage due to disease or accident can lead to progressive tissue deterioration. Cartilage tissue engineering, by replacing defective cartilage tissue, is a method for repairing such a problem. In this research, three main aspects-cell, biomaterial scaffold, and bioactive factors-that support tissue engineering study were optimized. Adipose-derived mesenchymal stem cells (ADSC) that become cartilage were grown in an optimized growth medium supplemented with either platelet rich plasma (PRP) or L-ascorbic acid (LAA). As the characterization result, the ADSC used in this experiment could be classified as Mesenchymal Stem Cell (MSC) based on multipotency analysis and cell surface marker analysis. The biomaterial scaffold was fabricated from the Bombyx morii cocoon using silk fibroin by salt leaching method and was engineered to form different sizes of pores to provide optimized support for cell adhesion and growth. Biocompatibility and cytotoxicity evaluation was done using MTT assay to optimize silk fibroin concentration and pore size. Characterized ADSC were grown on the optimized scaffold. LAA and PRP were chosen as bioactive factors to induce ADSC differentiation to become chondrocytes. The concentration optimization of LAA and PRP was analyzed by cell proliferation using MTT assay and chondrogenic differentiation by measuring glycosaminoglycan (GAG) using Alcian Blue at 605 nm wavelength. The optimum silk fibroin concentration, pore size, LAA concentration, and PRP concentration were used to grow and differentiate characterized ADSC for 7, 14, and 21 days. The cell morphology on the scaffold was analyzed using a scanning electron microscope (SEM). The result showed that the ADSC could adhere on plastic, express specific cell surface markers (CD73, CD90, and CD105), and could be differentiated into three types of mature cells. The silk fibroin scaffold made from 12% w/v concentration formed a 500 µm pore diameter (SEM analysis), and was shown by MTT assay to be biocompatible and to facilitate cell growth. The optimum concentrations of the bioactive factors LAA and PRP were 50 µg/mL and 10%, respectively. GAG analysis with Alcian Blue staining suggested that PRP induction medium and LAA induction medium on 12% w/v scaffold could effectively promote not only cell adhesion and cell How to cite this article Barlian A, Judawisastra H, Alfarafisa NM, Wibowo UA, Rosadi I. 2018. Chondrogenic differentiation of adipose-derived mesenchymal stem cells induced by L-ascorbic acid and platelet rich plasma on silk fibroin scaffold. PeerJ 6:e5809 http://doi.org/10.7717/peerj.5809 proliferation but also chondrogenic differentiation of ADSC within 21 days of culture. Therefore, this study provides a new approach to articular tissue engineering with a combination of ADSC as cell source, LAA and PRP as bioactive factors, and silk fibroin as a biocompatible and biodegradable scaffold.
JURNAL SELULOSA
The alkalized of petung bamboo fiber (Dendrocalamus asper) as reinforcement of polymer compositeP... more The alkalized of petung bamboo fiber (Dendrocalamus asper) as reinforcement of polymer compositePetung bamboo (Dendrocalamus asper) has good fiber characteristic and it has potential to substitute glass fiber as reinforcement in polymeric composite. However, like other natural based materials, bamboo fiber has a high variability in mechanical properties and inherently hygroscopic characteristic. Therefore it is required to optimize the petung bamboo qualities. The fiber optimization was carried out by alkalization process using NaOH solution with varying concentration of 0, 3, 5, and 10% v/v. Bamboo fiber processed in chemomechanical was used in this investigation. Characterization of density, mechanical and chemicals was conducted by pycnometry method, tensile strength testing, Fourier Transform Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). The data variability was analyzed by Weibull distribution. Result indicates that the optimum condition of alkalization process of...
Jurnal Sains Materi Indonesia, 2018
ABSTRAK SIFAT TARIK KOMPOSIT EPOKSI BERPENGUAT SERAT BAMBU AKIBAT PENYERAPAN AIR. Serat bambu mem... more ABSTRAK SIFAT TARIK KOMPOSIT EPOKSI BERPENGUAT SERAT BAMBU AKIBAT PENYERAPAN AIR. Serat bambu memiliki potensi sebagai serat penguat pengganti serat gelas dalam pembuatan komposit polimer, karena sifatnya yang terbaharui dan ramah lingkungan. Namun daya serap air yang tinggi pada serat bambu dapat menurunkan sifat tarik komposit yang dihasilkan. Hal ini akibat memburuknya ikatan antarmuka serat dan matriks. Penelitian ini bertujuan untuk mengkaji degradasi sifat tarik biokomposit epoksi berpenguat serat bambu petung akibat penyerapan air. Biokomposit epoksi berpenguat serat bambu petung dibuat dengan metode tekan panas dengan variasi serat tanpa alkalisasi (0 % NaOH) dan dengan alkalisasi (5 % NaOH). Pengujian biokomposit, dilakukan dengan cara uji air mendidih, uji tarik dan Scanning Electron Microscope (SEM). Kadar penyerapan air biokomposit tanpa alkalisasi lebih tinggi dibandingkan dengan biokomposit yang telah mengalami alkalisasi (5 % NaOH). Penyerapan air mengakibatkan degradasi pada biokomposit dan menurunkan kekuatan tarik biokomposit hingga 23 %. Perlakuan alkali 5 % NaOH, dapat meminimalisir persentase penurunan kekuatan biokomposit, dengan persentase penurunan kekuatan tarik sebesar 17 %. Hasil pemeriksaan pada permukaan patahan menunjang hasil pengujian tarik. Akibat penyerapan air, kekuatan tarik komposit epoksi bambu petung menurun karena sifat serat dan antarmuka serat matriks telah terdegradasi. ABSTRACT TENSILE PROPERTIES DECREMENT OF THE BAMBOO FIBER REINFORCED EPOXY COMPOSITE DUE TO WATER ABSORPTION. Bamboo fiber has potential as reinforcing fibers as subtitute to glass fiber for polymer composites, due to their renewable properties and environmental friendly. However, high water absorption in bamboo fibers, can reduce tensile properties of composites due to poor fiber-matrix interface. This research aims to study degradation of tensile properties of bamboo fiber reinforced epoxy composites caused by water absorption. Bamboo petung fiber reinforced epoxy biocomposites were fabricated by means compression molding method with fiber variations without alkalization (0 %) and with alkalization (5 %). Biocomposite examinations were carried out by means of water boiling test, tensile test and Scanning Electron Microscope (SEM). Water absorption of biocomposite without alkalization is higher than biocomposite with alkalization (5 % NaOH). Water absorption caused degradation on the biocomposites, and decreased the tensile strength up to 23 %. Alkalization 5 % NaOH minimized the percentage reduction of tensile strength with percentage reduction of tensile strength for 17 %. The results of examination on surface fracture support the tensile test results. Water absorption has lowered composite tensile strength due to occurrence of properties degradation on both fiber and fiber-matrix interface.