Fabrication of Porous Materials from Natural/Synthetic Biopolymers and Their Composites

Abstract

Biopolymers and their applications have been widely studied in recent years. Replacing the oil based polymer materials with biopolymers in a sustainable manner might give not only a competitive advantage but, in addition, they possess unique properties which cannot be emulated by conventional polymers. This review covers the fabrication of porous materials from natural biopolymers (cellulose, chitosan, collagen), synthetic biopolymers (poly(lactic acid), poly(lactic-co-glycolic acid)) and their composite materials. Properties of biopolymers strongly depend on the polymer structure and are of great importance when fabricating the polymer into intended applications. Biopolymers find a large spectrum of application in the medical field. Other fields such as packaging, technical, environmental, agricultural and food are also gaining importance. The introduction of porosity into a biomaterial broadens the scope of applications. There are many techniques used to fabricate porous polymers. Fabrication methods, including the basic and conventional techniques to the more recent ones, are reviewed. Advantages and limitations of each method are discussed in detail. Special emphasis is placed on the pore characteristics of biomaterials used for various applications. This review can aid in furthering our understanding of the fabrication methods and about controlling the porosity and microarchitecture of porous biopolymer materials.

Modified Water Displacement Method and its Use for Determination of Bulk Density of Porous Materials

“…One of such techniques is the micro-molding method adopted by Soumaya et al 2015 in fabricating porous polymethyl hydrosiloxane structure using porous silicon scaffolds. Several other researchers including but not limited to Aizawa 2018, Udeni et al 2016, Xiao-Yu 2017, He et al 2012, Jang et al 2014and Jun et al 2017 in their research reports, also confirmed the possibility of designing and developing useful porous materials of desired properties. In everyday life, the emerging properties of enormous practical importance exhibited by fabricated porous materials have led to a pronounced increase in the range of their applications from applied sciences to medical diagnosis and engineering.…”

Bone tissue engineering: Adult stem cells in combination with electrospun nanofibrous scaffolds

“…Collagen is a structural protein and exists in the most part of connective tissues, skin, bone, cartilage, and tendons. This protein as main protein type of the extracellular matrix provides structural, mechanical and biochemical properties (Daei‐farshbaf et al, ; Sampath, Ching, Chuah, Sabariah, & Lin, ). Baheiraei et al were fabricated and investigated collagen (COL) and collagen/beta tricalcium phosphate (COL/β‐TCP) scaffolds potential for use in bone tissue engineering and their results demonstrated that osteogenic markers were greatly increased in mouse BM‐MSCs cultured on composited scaffolds and also assisting to rapid vascularization (Baheiraei et al, ).…”

“…Chitosan exists in the exoskeleton crabs and shrimps and the bone of cuttlefish and squids, it is second numerous biopolymer in nature and also, it is a major abundant of fungi cell wall (Ardeshirylajmi, Delgoshaie, Mirzaei, & Khojasteh, ; Sampath et al, ). Developing the chitosan scaffold performance by employing suitable composites and materials showed promising potential of this kind of scaffold for bone tissue engineering applications.…”

“…Firstly, chitosan is highly adaptable for a variety of applications (Thangavel, Ramachandran, & Muthuvijayan, ). Apart from this, lower deacetylate chitosan scaffolds possess smaller pore sizes, higher mechanical strength, moderate swelling properties and greater cellular activities (Dhandayuthapani, Krishnan, & Sethuraman, ; Sampath et al, ; Zhong et al, ). Raftery et al was developed a collagen hydroxyapatite scaffold loaded with chitosan nanoparticles carrying genes encoding osteogenic (BMP‐2) and angiogenic (VEGF) proteins and applied for bone implantation at the site of critical size defect and results were showed that new bone formation significantly increased in animals that received composited scaffolds (Raftery et al, ).…”

“…Firstly, chitosan is highly adaptable for a variety of applications(Thangavel, Ramachandran, & Muthuvijayan, 2016). Apart from this, lower deacetylate chitosan scaffolds possess smaller pore sizes, higher mechanical strength, moderate swelling properties and greater cellular activities(Dhandayuthapani, Krishnan, & Sethuraman, 2010;Sampath et al, 2016;Zhong et al, 2011).Raftery et al was developed a collagen hydroxyapatite scaffold loaded with chitosan nanoparticles carrying genes encoding osteogenic (BMP-2) and angiogenic (VEGF) proteins and applied for bone implantation at the site of critical size defect and results were showed that new bone formation significantly increased in animals that received composited scaffolds(Raftery et al, 2017). Ruan et al developed a silk-fibroin/ chitosan/nano-hydroxyapatite (SF/CS/nHA) scaffold and cultured BM-MSCs on it; their results were showed that osteogenic differentiation potential was greatly increased when cultured on this scaffolds in comparison with other groups including SF/CS, SF/CS/nHA, and culture plates groups(Ruan, Yan, Deng, Huang, & Jiang, 2017).…”