Swapan Kumar Sarkar | Soonchunhyang Univ., Korea (original) (raw)

Papers by Swapan Kumar Sarkar

Metals and Materials International, 2012

Abstract In this study, we investigated the formation behavior of spherical porous biphasic calci... more Abstract In this study, we investigated the formation behavior of spherical porous biphasic calcium phosphate (BCP) granules, in which PCL was both the binder and fugitive pore former. The formation of porous granules was based on the immiscibility of PCL slurry containing BCP powder and distilled water. The porosity was controlled by controlling the volume fraction of PCL. In addition, the effect of the composition on the rheological properties and consequently the droplet formation mechanism was examined. After drying ...

Journal of applied biomaterials & functional materials, 2018

Magnesium (Mg)-based alloys are considered to be promising materials for implant application due ... more Magnesium (Mg)-based alloys are considered to be promising materials for implant application due to their excellent biocompatibility, biodegradability, and mechanical properties close to bone. However, low corrosion resistance and fast degradation are limiting their application. Mg-Ca alloys have huge potential owing to a similar density to bone, good corrosion resistance, and as Mg is essential for Ca incorporation into bone. The objective of the present work is to determine the in vitro degradation and in vivo performance of binary Mg- xCa alloy ( x = 0.5 or 5.0 wt%) to assess its usability for degradable implant applications. Microstructural evolutions for Mg- xCa alloys were characterized by optical, SEM, EDX, and XRD. In vitro degradation tests were conducted via immersion test in phosphate buffer saline solution. In vivo performance in terms of interface, biocompatibility, and biodegradability of Mg- xCa alloys was examined by implanting samples into rabbit femoral condyle for...

Korean Journal of Materials Research

In this study, we fabricated a novel micro porous hybrid scaffold of biphasic calcium phosphate (... more In this study, we fabricated a novel micro porous hybrid scaffold of biphasic calcium phosphate (BCP) and a polylectrolyte complex (PEC) of chitosan (CS) and hyaluronic acid (HA). The fabrication process included loading of CS-HA PEC in a bare BCP scaffold followed by lypophilization. SEM observation and porosimetry revealed that the scaffold was full of micro and macro pores with total porosity of more than 60 % and pore size in the range of 20~200 µm. The composite scaffold was mechanically stronger than the bare BCP scaffold and was significantly stronger than the CS-HA PEC polymer scaffold. Bone morphogenetic growth factor (BMP-2) was immobilized in CS-HA PEC in order to integrate the osteoinductive potentiality required for osteogenesis. The BCP frame, prepared by sponge replica, worked as a physical barrier that prolonged the BMP-2 release significantly. The preliminary biocompatibility data show improved biological performance of the BMP-2 immobilized hybrid scaffold in the presence of rabbit bone marrow stem cells (rBMSC).

Korean Journal of Materials Research, 2013

This paper investigates the effect of prolonged high temperature exposure on concentric laminated... more This paper investigates the effect of prolonged high temperature exposure on concentric laminated Al 2 O 3-ZrO 2 composites. An ultrafine scale microstructure with a cellular 7 layer concentric lamination with unidirectional alignment was fabricated by a multi-pass extrusion method. Each laminate in the microstructure was 2-3 µm thick. An alternate lamina was composed of 75%Al 2 O 3-(25%m-ZrO 2) and t-ZrO 2 ceramics. The composite was sintered at 1500 o C and subjected to 1450 o C temperature for 24 hours to 72 hours. We investigated the effect of long time high temperature exposure on the generation of residual stress and grain growth and their effect on the overall stability of the composites. The residual stress development and its subsequent effect on the microstructure with the edge cracking behavior mechanism were investigated. The residual stress in the concentric laminated microstructure causes extensive micro cracks in the t-ZrO 2 layer, despite the very thin laminate thickness. The material properties like Vickers hardness and fracture toughness were measured and evaluated along with the microstructure of the composites with prolonged high temperature exposure.

PloS one, 2016

A bipotential polyelectrolyte complex with biphasic calcium phosphate (BCP) powder dispersion pro... more A bipotential polyelectrolyte complex with biphasic calcium phosphate (BCP) powder dispersion provides an excellent option for protein adsorption and cell attachment and can facilitate enhanced bone regeneration. Application of the bipotential polyelectrolyte complex embedded in a spongy scaffold for faster healing of large segmental bone defects (LSBD) can be a promising endeavor in tissue engineering application. In the present study, a hollow scaffold suitable for segmental long bone replacement was fabricated by the sponge replica method applying the microwave sintering process. The fabricated scaffold was coated with calcium alginate at the shell surface, and genipin-crosslinked chitosan with biphasic calcium phosphate (BCP) dispersion was loaded at the central hollow core. The chitosan core was subsequently loaded with BMP-2. The electrolytic complex was characterized using SEM, porosity measurement, FTIR spectroscopy and BMP-2 release for 30 days. In vitro studies such as MTT...

Materials Transactions, 2010

A micro-channeled composite with a laminated microstructure was fabricated in Al 2 O 3-ZrO 2 comp... more A micro-channeled composite with a laminated microstructure was fabricated in Al 2 O 3-ZrO 2 composite system through a multipass extrusion process. Using this approach, Al 2 O 3-(monoclinic-ZrO 2)/tetragonal-ZrO 2 continuously porous composites with concentric laminates were fabricated. The entire matrix phase had a laminated microstructure of alternate lamina of Al 2 O 3-(m-ZrO 2) and t-ZrO 2 with a homogeneous thickness and central channel. Each of the continuous channels was coaxially encircled by a group of 5 alternate laminates. The laminate plane was oriented along the axis of the continuous channels. The design strategy was to incorporate concentric lamellar microstructural units in a macro scaled ceramic body comprising a central channel for each. The frame modification was intended to improve the material properties of the channeled body which in turn could act as a porous space for the inclusion of additional functional attributes. Filaments of polymer mixed ceramic powders and pore forming agent carbon were stacked in a pre-designed arrangement to obtain the desired microstructure and then extruded to obtain green composites. The channel diameter and channel frame thickness were approximately 198 AE 10 mm and 158 AE 10 mm, respectively. The channel frame region was furnished with 9 alternating shells of Al 2 O 3-(m-ZrO 2) and t-ZrO 2 with a thickness of around 10$20 mm. The material properties including the relative density and bending strength, which depend on temperature, were evaluated. The detailed microstructure of the channeled bodies was also characterized by Scanning Electron Microscope (SEM).

J Mater Sci Mater Med, 2009

Using 80 vol.% of poly methyl methacrylate (PMMA) as a pore-forming agent to obtain interconnecte... more Using 80 vol.% of poly methyl methacrylate (PMMA) as a pore-forming agent to obtain interconnected porous bodies, porous Al(2)O(3)-(m-ZrO(2)) bodies were successfully fabricated. The pores were about 200 microm in diameter and were homogeneously dispersed in the Al(2)O(3)-25 vol.% (m-ZrO(2)) matrix. To obtain Al(2)O(3)-(m-ZrO(2))/bioglass composites, the molten bioglass was infiltrated into porous Al(2)O(3)-(m-ZrO(2)) bodies at 1400 degrees C. The material properties of the Al(2)O(3)-(m-ZrO(2))/bioglass composites, such as relative density, hardness, compressive strength, fracture toughness and elastic modulus were investigated.

Scripta Materialia, 2009

Continuously porous Al2O3–(monolinic-ZrO2)/tetragonal-ZrO2 ceramic composites with tailored fine-... more Continuously porous Al2O3–(monolinic-ZrO2)/tetragonal-ZrO2 ceramic composites with tailored fine-scale fibrous microstructure was fabricated by a multipass extrusion process. Precise control of the microstructure was achieved, giving Al2O3–(m-ZrO2) fibrous phase (3.5 μm) in the t-ZrO2 phase (1.5 μm thickness). The pore size and porosity was 175μm and 36%. The rounded microchannels and fine geometric control of the fibrous microstructure result in composites with a remarkably high bending strength value of 588MPa which is 2- ...

Ceram Int, 2010

Microstructural variations in the Al 2 O 3-(monoclinic-ZrO 2)/tetragonal-ZrO 2 core/shell composi... more Microstructural variations in the Al 2 O 3-(monoclinic-ZrO 2)/tetragonal-ZrO 2 core/shell composites (Al 2 O 3-(m-ZrO 2)/t-ZrO 2) were tailored using different volume fractions of the core and shell by the multi-pass co-extrusion process. To introduce continuously fibrous microtextures with varying dimensions of microstructure, various volume fractions of the Al 2 O 3-(m-ZrO 2) core and t-ZrO 2 shell phases were used (40/60, 50/50 and 60/40). The effect of the number of extrusion passes on the control of microstructure and the corresponding composite's mechanical properties were investigated. The bending strength and fracture toughness values were shown to increase as the t-ZrO 2 shell volume fraction increased, which was unlike the Vickers hardness value. However, the fracture toughness value was higher for 4th pass composites compared to 5th pass composites due to the presence of the fibrous core/shell microstructure. In addition, the bending strength was higher for 5th pass composites. Detailed microstructural analysis was carried out by SEM.

Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi, 2009

Journal of Bioactive and Compatible Polymers, 2015

Blood serum contains various kinds of proteins which are necessary for tissue repair and regenera... more Blood serum contains various kinds of proteins which are necessary for tissue repair and regeneration process. Defect healing of fractured bone is initiated by the influx of blood and then clot formation. Thus, proteins in serum may have the ability to stimulate the bone regeneration process. In this work, we investigated the fabrication of serum-loaded oxidized alginate–gelatin–biphasic calcium phosphate hydrogels with various contents of blood serum (0%, 5%, 10%, and 15% in % v/v) to evaluate the stimulatory effect of serum proteins on bone regeneration. This system was also evaluated for rat bone marrow–derived stem cell delivery to get faster bone healing. The serum-loaded oxidized alginate–gelatin–biphasic calcium phosphate hydrogel samples were characterized by scanning electron microscopy, porosity meter, X-ray diffraction, and Fourier transform infrared for morphology and phase characterization together with their mechanical behavior. Protein release behavior, degradation, a...

Journal of biomaterials applications, 2015

Microporous calcium phosphate based synthetic bone substitutes are used for bone defect healing. ... more Microporous calcium phosphate based synthetic bone substitutes are used for bone defect healing. Different growth factor loading has been investigated for enhanced bone regeneration. The platelet is a cellular component of blood which naturally contains a pool of necessary growth factors that mediate initiation, continuation, and completion of cellular mechanism of healing. In this work, we have investigated the encapsulation and immobilization of platelet-rich plasma (PRP) with natural polymers like hyaluronic acid (HA) and gelatin (Gel) and loading them in a biphasic calcium phosphate (BCP) scaffold, for a synthetic-allologous hybrid scaffold. Effect of PRP addition in small doses was evaluated for osteogenic potential in vitro and in vivo. BCP (10%) mixed HA-Gel hydrogel with or without PRP, was loaded into a BCP sponge scaffold. We investigated the hydrogel-induced improvement in mechanical property and PRP-mediated enhancement in biocompatibility. In vitro studies for cytotoxic...

Journal of Materials Research, 2014

ABSTRACT

Journal of Biomaterials Applications, 2014

Collagen- and gelatin-coated porous spherical granule was prepared by slurry dripping process usi... more Collagen- and gelatin-coated porous spherical granule was prepared by slurry dripping process using biphasic calcium phosphate powder. The coating was stabilized by cross-linking with dimethyl 3,3&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;-dithiobispropionimidate di-hydrogenchloride (DTBP). Afer DTBP cross-linking, the nanostructure of collagen- and gelatin-coated surfaces was changed from smooth to fibrous and net-like structure. Excellent cross-linking of the coating was seen as indicated by the differential scanning calorimetry thermogram and the Fourier transform infrared spectroscopy spectra. After cross-linking the relative intensities of the Fourier transform infrared spectroscopy peaks were decreased and amide bands were shifted to the left. The interaction of gelatin with DTBP cross-linking agent was stronger than that with collagen according to differential scanning calorimetry and Fourier transform infrared spectroscopy results. The compressive strength of the granular bone substitutes increased significantly after the coating process and gelatin coated biphasic calcium phosphate granules showed highest value at 3.68 MPa after cross-linking. Porosity was greater than 63% and did not change significantly with coating. Biocompatibility investigation by in vitro and in vivo showed that the coating improved the cell proliferation marginally. However, the cross-linking process did not jeopardize the excellent biocompatibility of collagen and gelatin. The in vivo study confirms better bone formation behavior of the cross-linked gelatin and collagen coated samples investigated for 8 weeks in vivo.

European Ceramic Society. Journal, 2012

Needle-shaped TiO 2 fibres were fabricated inside a micro-channelled Al 2 O 3-ZrO 2 composite por... more Needle-shaped TiO 2 fibres were fabricated inside a micro-channelled Al 2 O 3-ZrO 2 composite porous membrane system using the sol-gel method. The micro-channelled Al 2 O 3-ZrO 2 composite was fabricated using the fibrous monolithic process. Pure anatase phase TiO 2 was crystallised from the as-coated amorphous phase during calcination at 510 C. The TiO 2 fibres grew on the surface frame of the micro-channelled Al 2 O 3-ZrO 2 composite membrane and fully covered the inside of the micro-channelled pores. The specific ...

The Korean Journal of Internal Medicine, 2015

Bone is a unique organ composed of mineralized hard tissue, unlike any other body part. The uniqu... more Bone is a unique organ composed of mineralized hard tissue, unlike any other body part. The unique manner in which bone can constantly undergo self-remodeling has created interesting clinical approaches to the healing of damaged bone. Healing of large bone defects is achieved using implant materials that gradually integrate with the body after healing is completed. Such strategies require a multidisciplinary approach by material scientists, biological scientists, and clinicians. Development of materials for bone healing and exploration of the interactions thereof with the body are active research areas. In this review, we explore ongoing developments in the creation of materials for regenerating hard tissues.

Sintering of Ti-biphasic calcium phosphate (BCP) is difficult because of the chemical instability... more Sintering of Ti-biphasic calcium phosphate (BCP) is difficult because of the chemical instability of the phases at high temperature. When the sintering temperature is above 1273 K, Ti reacts with BCP and forms CaO, TiO 2, CaTiO 3, TiP etc. Conventional vacuum sintering is common for Ti powder but for Ti-BCP composites, spark plasma sintering in an inert atmosphere is a quick method to overcome the issues associated with a prolonged reaction time.

Journal of biomaterials application, Mar 2013

In this work, we fabricated injectable bone substitutes modified with the addition of bioactive g... more In this work, we fabricated injectable bone substitutes modified with the addition of bioactive glass powders synthesized via ultrasonic energy-assisted hydrothermal method to the calcium phosphate-based bone cement to improve its biocompatibility. The injectable bone substitutes was initially composed of a powder component (tetracalcium phosphate, dicalcium phosphate dihydrate and calcium sulfate dehydrate) and a liquid component (citric acid, chitosan and hydroxyl-propyl-methyl-cellulose) upon which various concentrations of bioactive glass were added: 0%, 10%, 20% and 30%. Setting time and compressive strength of the injectable bone substitutes were evaluated and observed to improve with the increase of bioactive glass content. Surface morphologies were observed via scanning electron microscope before and after submersion of the samples to simulated body fluid and increase in apatite formation was detected using x-ray diffraction machine. In vitro biocompatibility of the injectable bone substitutes was observed to improve with the addition of bioactive glass as the proliferation/adhesion behavior of cells on the material increased. Human gene markers were successfully expressed using real time-polymerase chain reaction and the samples were found to promote cell viability and be more biocompatible as the concentration of bioactive glass increases. In vivo biocompatibility of the samples containing 0% and 30% bioactive glass were evaluated using Micro-CT and histological staining after 3 months of implantation in male rabbits' femurs. No inflammatory reaction was observed and significant bone formation was promoted by the addition of bioactive glass to the injectable bone substitute system.

Materials Science Forum, 2010

... Dong-Woo Jang, Swapan Kumar Sakar, Minsung Kim, Yong-Ki Min, Ho-Yeon Song, and Byong-Taek Lee... more ... Dong-Woo Jang, Swapan Kumar Sakar, Minsung Kim, Yong-Ki Min, Ho-Yeon Song, and Byong-Taek Lee* ... [7] Klawitter JJ, Bagwell JG, Weinstein AM, Sauer BW: J Biomed Mater Res 1976,10:311–23. [8] Ripamonti U, Van den Heever B, Van Wyk J: Matrix 1993,13:491–502. ...