Table 1: Sodium alginate characteristic recommended by the European Pharmacopeia (Eur. Ph.) and United States Pharmacopeia (USP) [5, 6].

ParameterEur. Ph. 8.0USP 32-NF 27

Appearance of solid productWhite or pale yellowish-brown powdern.d.
Contentn.d.90.8%–106.0% of dried basis
Packaging and storagen.d.preserved in tight containers
SolubilitySlowly soluble in water, practically insoluble in ethanol 96%n.d.
Appearance of solutionNot more opalescent than reference formazin suspension in water and not more intensely coloured than intensity 6 of the range of reference solutions of the most appropriate colourn.d.
Heavy metals≤20 ppm≤0.004%
Chlorides≤1.0%n.d.
Calcium≤1.5%n.d.
Arsenicn.d.≤1.5 ppm
Loss on drying≤15.0%≤15.0%
Total ashn.d.18.0%–27.0%
Sulfated ash30.0%–36.0%n.d.
Microbial limitsTAMC: ≤1000 cfu/g≤200 cfu/g
TYMC: ≤100 cfu/g
Absence of specified microorganismsSalmonella sp., Escherichia coliSalmonella sp., Escherichia coli

n.d.: not determined, TAMC: total aerobic microbial count, and TYMC: total yeast/moulds count.