Characterization and properties of sodium alginate from brown algae used as an ecofriendly superabsorbent

Abstract

Abstract. Sodium alginate obtained from the extraction of brown algae is used as the backbone for the synthesis of superabsorbent nanocomposite copolymerization. The first stage of extraction is the demineralization process using 0.1 M HCl solution and then 2% Na2CO3 solution for 2 hours at 60°C. The rendement of sodium alginate obtained was 44.32% with molecular weight of 40680 g/mol with measurement of the intrinsic viscosity. FTIR spectra of sodium alginate showed mannuronic acid functional group at wavenumber 884 cm -1 and the uronic acid at wavenumber 939 cm -1 , OH functional group at wavenumber 3200-3400 cm -1 , and CH2 stretching at wavenumber 2928 cm -1 . The diffraction pattern of isolated sodium alginate has specific 2θ at 13.068 and 21.096, amorphous intensity found specific 2θ at 18.058, and the obtained crystallinity degree of the sodium alginate is equal to 29.292% from the XRD analysis. The morphological analysis by SEM shows fibrils of isolated sodium alginate. The success isolation of sodium alginate from brown algae is supported by DSC which shows the decomposition temperature of pure sodium alginate and isolated alginate have close values, namely 251.12°C for pure sodium alginate and 229.90°C for isolated sodium alginate.

Bilayer Cylindrical Conduit Consisting of Electrospun Polycaprolactone Nanofibers and DSC Cross‐Linked Sodium Alginate Hydrogel to Bridge Peripheral Nerve Gaps

“…Bulk sodium alginate showed the characteristic peaks at 811 cm −1 , 962 cm −1 , and 3431 cm −1 that were attributed to mannuronic acid, uronic acid, and OH stretching, respectively (Figure 2a). The sharp peaks at 2922 cm −1 was related to CH stretching, [ 36 ] while other modes of COC vibrations in polysaccharide were identified by the bands at 1086 and 1160 cm −1 . Moreover, the asymmetrical stretching peak of carboxylate salt groups (OCO) shifted to 1651 cm −1 and the symmetrical stretching of OCO groups shifted to 1445 cm −1 .…”

“…Moreover, the asymmetrical stretching peak of carboxylate salt groups (OCO) shifted to 1651 cm −1 and the symmetrical stretching of OCO groups shifted to 1445 cm −1 . [ 36 ] After adding DSC to sodium alginate, formation of carbonate compound was confirmed by the appearance of N‐hydroxysuccinimide (NHS) band (or DSC) at 1704 cm −1 correspondence to asymmetric carbonyl stretch (CO) (Figure 2b). CN stretching (CNC) at 1229 cm −1 , CH stretching at 1457 cm −1 , and the CO stretching at 1083 cm −1 also confirmed the formation of succinimidyl groups.…”

THE EXTRACTION OF BROWN ALGAE (Sargassum sp) THROUGH CALCIUM PATH TO PRODUCE SODIUM ALGINATE

“…The research was conducted by experiment of brown seaweed extract conventionally (through calcium alginate) with 5, 6, and 7 hours extraction time variables at 50 and 60 o C respectively. The alginate extraction process is carried out by converting alginic acid to sodium alginate having water soluble properties using 2% Na2CO3 solution as stated by Helmiyati and Aprilliza (2017) that extraction using Na2CO3 (sodium carbonate) is capable of separating the cellulose and alginate present in brown algae cells. After the depigmentation process and the removal of fat sequentially with 2% formalin and 0.2 M HCl (1:30 w/v) for 24 hours at 30°C under constant stirring, the average sodium alginate yield as shown in Table 1.…”

Characterization of Alginate from Sargassum duplicatum and the Antioxidant Effect of Alginate–Okra Fruit Extracts Combination for Wound Healing on Diabetic Mice

“…However, the extraction yield was lower than alginate from C. implexa and L. variegate of 29.15 and 27.57% [41], S. angustifolium and Sargassum sp. of 40.78 and 44.32%, respectively [42,43]. In general, the content of alginate in various types of brown seaweed varies widely are depending on species and the method for extraction used [44].…”