Alginate Salts & Esters

Swap the counter-ion on an alginate chain and you effectively swap materials. Sodium alginate dissolves in cold water into a smooth, pseudoplastic solution; the calcium salt refuses to dissolve at all and prefers to hold things together instead; esterify the carboxyl groups with propylene glycol and the polymer suddenly tolerates acid that would crash plain alginate. Eata Marisource works across this whole family, converting brown seaweed into a full line of alginate salts and esters for research teams, formulators and industrial processors.

What that means in practice: one supplier who understands why a textile printer wants a low-viscosity, fine-mesh sodium alginate while a biomaterials lab asks for high-G calcium alginate and a beverage plant needs an acid-stable PGA. Different problems, different chemistry, same seaweed supply chain.

One Polymer, Several Personalities

Alginic acid is a linear copolymer of β-D-mannuronic acid (M) and α-L-guluronic acid (G) units drawn from brown algae such as Saccharina, Ascophyllum and Macrocystis. The M-to-G ratio, and how those units cluster into blocks, decides nearly everything: high-G alginates chelate calcium into stiff, brittle egg-box gels, while high-M grades swell into softer, more elastic networks. We characterise every lot's composition by ¹H NMR and can recommend or blend grades so the behaviour you specify is the behaviour you get.

The Alginate Family We Supply

Picking the Right Form

• Need a smooth solution fast? Sodium or potassium alginate hydrate cleanly in cold water; ammonium alginate follows closely behind.
• Need something that will not dissolve? Calcium alginate stays put in water yet swaps ions with sodium on contact — the trick behind absorbent fibre technology.
• Working below pH 4? Sodium alginate gels or precipitates in acid conditions; PGA keeps thickening and stabilising where the sodium salt gives up.
• Chasing maximum gel strength? Ask for high-G grades; elasticity and softer networks point to high-M material instead.

Viscosity on Your Terms

Viscosity is the dial buyers turn most often, so we grade against a standard 1% solution at 20 °C and hold the tolerance tight:

Standard analytical targets across soluble grades: pH 6.0–8.0, moisture ≤15%, ash 20–24% (sodium salt), water-insolubles ≤0.6–3% by grade, calcium ≤0.3–0.4%; particle size cut anywhere from 30 to 200 mesh on request. PGA ships with degree of esterification ≥80%, pH 3.0–4.5 (1% solution) and total propylene glycol 15–45%.

Where Each Form Earns Its Keep

• Printing and textiles: reactive-dye print pastes on cotton and blends, with sharp definition and high colour yield from alginate thickeners
• Biomaterials research: Ca²⁺ crosslinked gels for cell encapsulation, 3D bioink formulations and porous freeze-dried scaffolds
• Beverage and emulsion work: PGA suspending pulp and stabilising foam in acidic systems
• Absorbent materials: calcium alginate fibre for high-fluid-uptake nonwoven studies
• Industrial side of the house: welding-rod binders, paper coating, and flocculation trials in water treatment

Every Lot, Checked Against Its Own Spec

• ¹H NMR block composition (M/G ratio) and molecular weight profile
• Viscosity verification at declared grade, temperature and concentration
• Moisture, ash, pH and water-insoluble matter per grade standard
• Heavy metals and arsenic screening; microbiology panel on cosmetic and feed-adjacent grades
• PGA-specific panel: esterification degree, free and total propylene glycol

Packing, Documents, Scale

Research quantities go out in 1 kg packs; production orders ship in 25 kg poly-lined bags or fibre drums, pelletised or palletised to your warehouse standard. CoA, TDS and SDS travel with every consignment, and retained samples are held against each lot number so repeat orders stay repeatable.

Built Around Your Spec Sheet

If the grade you need is not a catalogue row, describe it: target viscosity, mesh, M/G window, esterification degree, counter-ion, or a blend of two lots. Custom production runs, custom mesh milling and private packaging are routine work here — send the specification and we will quote against it without a lecture on what you should have wanted instead.

For Research or Industrial Raw Materials, Not For Personal Medical Use!