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Producing large beads from alginate. Principle and equipment. Principle. Alginate solution + divalent cations (Ca, Ba, etc.) = solidified matrix (gel-like material). If alginate solution is forced into a droplet shape, the result will be a solid bead (sphere).
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Producing large beads from alginate Principle and equipment
Principle Alginate solution +divalent cations (Ca, Ba, etc.)=solidified matrix(gel-like material) If alginate solution is forced into a droplet shape, the result will be a solid bead (sphere)
Producing beads in small quantities • The alginate solution is dripped, one drop at the time from a large syringe into solution of calcium chloride • The beads are instantly formed in the CaCl2 solution
…If all you need are a few grams of beads for your experiments… The method just shown is ideal and you need not read further. However…….
…If your experiment requires large quantities of beads (one or more liters)… You will find the syringe method very tiresome, especially when hard beads are needed when employing highly viscous alginate solutions Some equipment is needed
Equipment for producing large beads (2-4 mm dia.) • This is essentially a showerhead metal container, • With specially-designed nozzles. • Bead form by the force of gravity.
In real life, the device looks like this. Alginate solution Droplets Nozzle plate Formed beads
It can be made in a smaller size (or larger). Nozzle plate
Immobilization (entrapment) of one bacterial species and co-immobilization of two (or more) microorganisms inside the bead Chlorella + Azospirillum + Alginate = co-immobilization 3 mm
Potential use of large beads • Industry (production of microbial compounds) • Wastewater treatment (removal of contaminants) • Agriculture (production of bacterial inoculants)
Industry (fermentation) Microorganisms entrapped in alginate are often grown in large fermentation vats, similar to the vat pictured at left. The products they produce are harvested, while the beads remain inside the vat.
Wastewater treatment Something for the future-- Large-scale treatment by immobilized and co- immobilized microorganisms
Agriculture (bacterial inoculants) before sowing Beads Seeds
Other applications? The sky is the limit… Use your imagination
Some unexpected benefits • It does not require human energy, let alone paid energy. • It is accepted technology, published in most scientific journals. (Your “brilliant” paper will not be rejected on the basis of an untried method.) • As an environmentally-friendly technology, using it will make you look good. • Have fun…..