BC-alginate

Alginate is widely used in separation, food, textile, and paper applications. Moreover, due to its biocompatibility, alginate has been extensively used in the biomedical field as a drug delivery material [34, 35], a wound dressing [36], a scaffold [37, 38] and for cell encapsulation [39]. Therefore, the BC-alginate composite has been extensively studied in many fields. Comparative characteristics of BC-alginate composites prepared from various methods are shown in Table 14.1. 

Chemical structure Intermolecular interaction between hydroxyl group of BC and carboxyl group of alginate [23, 31,40,42] 

WVTR Slight reduction of Improvement of WVTR with WVTR with increasing increasing alginate content of alginate content [23] [31] 

Application Membrane Mucosal flap in oral tissue separation [23] (promotion ofkeratinocyte and gingival fibroblast proliferations] [40] Yeast cells carrier for ethanol production (high ethanol productivity] [41] 

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Figure 14.3 SEM images of BC-alginate films prepared by biosynthesis (a], by slurry blending (b], and by solution blending (c).

By preparing a three-dimensional BC-alginate composite sponge, the mixture of homogenized BC and alginate solution was cross-linked with a calcium chloride solution and then freeze... 

Alginate is a highly hydrophilic biopolymer and easily adsorbs water molecules. Therefore, the addition of alginate caused an increase in the WAC of the BC-alginate composite. Additionally, alginate can disrupt and reduce the hydrogen bonding of BC, which also results in the easy adsorption of water [31]. 

Table 14.2 Comparative characteristics of BC-alginate composites prepared from various methods...

BC/alginate nanocomposites have also been efficaciously prepared and tested in dissimilar applications, including biomedical devices [124], separation membranes [125]... 

Figure 2.15 SEM images of cross-section and surface of native BC/alginate carrier 0 h (A and C) and after 72h batch fermentation (C and D). Reproduced with permission from [126].

The intermolecular interaction between the hydroxyl functional group of BC and the carboxyl functional group of alginate was detected using Fourier transform infrared [FT-IR] spectroscopy. 

Svensson et al. (2005) used unmodified and modified (by chennical sulfation and phosphorylation) BC to study the cell culture of bovine chondrocytes with incorporation of collagen and alginate. They found that unmodified BC supports chondrocyte proliferation on 50% of the collagen type II substrate. Fig. 9.5(a) shows the SEM image of chondrocytes attached to a BC scaffold that show a round morphology. Modified BC showed no effect on chondrocyte growth after chemical sulfation and phosphorylation (Svensson et al., 2005). Andersson et al. (2010) used human chondrocytes... 

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