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7 Applications of Bionanocomposite Materials
7.2 Medical Applications
Natural abundance, adaptability and environmental friendliness make bionanocomposites a suitable material candidate for a wide range of medical applications such
as the regeneration of natural tissue structures. In this area, bionanocomposites can
be fabricated to have the same morphology as that of extracellular matrix (ECM)
including protein, polysaccharides and inorganic matters [5]. For bone regeneration
of clinical orthopaedics, the selection of bionanocomposites such as polymer scaffolds and hydroxyapatites (HAPs) with biodegradable and bioresorbable structures is
critical to stimulate the bone formation at the implantation sites [6] More importantly,
sufficient porosity is required for the structures of such bionanocomposites so that
new tissue growth can be facilitated like porous scaffolds based on HAP/collagen
nanocomposites in order to repair bony defects in animal models [7]. It is worth
mentioning that PVA/HNT bionanocomposite films have also been utilised in tissue
engineering with good compatibility to osteoblast and fibroblast cells [8].
In a similar manner, chitosan/HNT nanocomposite scaffolds exhibit highly porous
structures with high compressive strength and compressive modulus for the development of mouse fibroblasts [9]. No adverse effect is evidently shown for electrospun
poly(lactic-co-glycolic acid) (PLGA)/HNT bionanocomposites with high biocompatibility and cell proliferation when incorporated with HNTs [10]. The potential of
using bionanocomposites in drug delivery has been widely reported in the previous
studies [11, 12]. Nanocomposites reinforced with HNTs become a promising drug
carrier to be loaded in different forms of powders, suspensions and fibrous scaffolds
[13]. A slow release rate occurs when the lumen and outer surfaces of HNTs are
loaded with diltiazem hydrochloride, 5-aminosalicylic acid and propanol hydrochloride [13]. However, HNT loading capacity is limited because the lumen volume
fraction of HNTs cannot exceed 10 vol% [14]. The increase in loading capacity of
HNTs can be achieved by etching alumina from HNT inner surfaces. Additionally, the
inclusion of coated HNTs into biopolymers such as PVA [15], poly (ethyleneimine)
(PEI) [16] and chitosan [17] has also been shown to significantly retard a drug release
rate, as opposed to those uncoated counterparts.
7.3 Packaging Applications
In general, biopolymers have major drawbacks such as narrow processing window,
poor gas/water barrier properties, as well as weak mechanical properties when
compared with those of conventional synthetic polymers, which can be overcome
by the inclusion of nanofillers into neat biopolymers to produce bionanocomposite
materials. The characteristic permeability is one of the most important factors in food
packaging industries when suitable materials are selected [18].
7 Applications of Bionanocomposite Materials
7.2 Medical Applications
Natural abundance, adaptability and environmental friendliness make bionanocomposites a suitable material candidate for a wide range of medical applications such
as the regeneration of natural tissue structures. In this area, bionanocomposites can
be fabricated to have the same morphology as that of extracellular matrix (ECM)
including protein, polysaccharides and inorganic matters [5]. For bone regeneration
of clinical orthopaedics, the selection of bionanocomposites such as polymer scaffolds and hydroxyapatites (HAPs) with biodegradable and bioresorbable structures is
critical to stimulate the bone formation at the implantation sites [6] More importantly,
sufficient porosity is required for the structures of such bionanocomposites so that
new tissue growth can be facilitated like porous scaffolds based on HAP/collagen
nanocomposites in order to repair bony defects in animal models [7]. It is worth
mentioning that PVA/HNT bionanocomposite films have also been utilised in tissue
engineering with good compatibility to osteoblast and fibroblast cells [8].
In a similar manner, chitosan/HNT nanocomposite scaffolds exhibit highly porous
structures with high compressive strength and compressive modulus for the development of mouse fibroblasts [9]. No adverse effect is evidently shown for electrospun
poly(lactic-co-glycolic acid) (PLGA)/HNT bionanocomposites with high biocompatibility and cell proliferation when incorporated with HNTs [10]. The potential of
using bionanocomposites in drug delivery has been widely reported in the previous
studies [11, 12]. Nanocomposites reinforced with HNTs become a promising drug
carrier to be loaded in different forms of powders, suspensions and fibrous scaffolds
[13]. A slow release rate occurs when the lumen and outer surfaces of HNTs are
loaded with diltiazem hydrochloride, 5-aminosalicylic acid and propanol hydrochloride [13]. However, HNT loading capacity is limited because the lumen volume
fraction of HNTs cannot exceed 10 vol% [14]. The increase in loading capacity of
HNTs can be achieved by etching alumina from HNT inner surfaces. Additionally, the
inclusion of coated HNTs into biopolymers such as PVA [15], poly (ethyleneimine)
(PEI) [16] and chitosan [17] has also been shown to significantly retard a drug release
rate, as opposed to those uncoated counterparts.
7.3 Packaging Applications
In general, biopolymers have major drawbacks such as narrow processing window,
poor gas/water barrier properties, as well as weak mechanical properties when
compared with those of conventional synthetic polymers, which can be overcome
by the inclusion of nanofillers into neat biopolymers to produce bionanocomposite
materials. The characteristic permeability is one of the most important factors in food
packaging industries when suitable materials are selected [18].