Producing large beads Producing large beads from alginatefrom alginate

Principle and equipmentPrinciple and equipment

PrinciplePrinciple

Alginate solution Alginate solution ++ divalent cations divalent cations (Ca, Ba, etc.)(Ca, Ba, etc.) == solidified matrixsolidified matrix (gel-like material)(gel-like material)

If alginate solution is If alginate solution is forcedforced into a into a dropletdroplet shape, the result will be a shape, the result will be a solid beadsolid bead (sphere) (sphere)

Producing beads in Producing beads in small quantitiessmall quantities

• The alginate solution The alginate solution is dripped, one drop is dripped, one drop at the time from a at the time from a large syringe into large syringe into solution of calcium solution of calcium chloridechloride

• The beads are The beads are instantly formed in instantly formed in the CaClthe CaCl22 solution solution

One more time to get One more time to get the idea right…the idea right…

……If all you need are a few If all you need are a few grams of beads for your grams of beads for your

experiments…experiments…

The method just shown is ideal The method just shown is ideal and you need not read further.and you need not read further.

However…….However…….

……If your experiment If your experiment requires large quantities of requires large quantities of

beads (one or more liters)…beads (one or more liters)…

You will find the syringe method very You will find the syringe method very tiresome, especially when hard tiresome, especially when hard beads are needed when employing beads are needed when employing highly viscous alginate solutionshighly viscous alginate solutions

Some equipment is neededSome equipment is needed

Equipment for producing Equipment for producing large beads (2-4 mm dia.)large beads (2-4 mm dia.)

• This is essentially a This is essentially a showerhead metal showerhead metal container,container,

• With specially-With specially-designed nozzles.designed nozzles.

• Bead form by the Bead form by the force of gravity.force of gravity.

In real life, the device In real life, the device looks like this.looks like this.

Nozzle plateNozzle plate

Alginate solutionAlginate solution

DropletsDroplets

Formed beadsFormed beads

It can be made in a It can be made in a smaller size (or larger).smaller size (or larger).

Nozzle plateNozzle plate

Immobilization (entrapment) of one bacterial Immobilization (entrapment) of one bacterial species and co-immobilization of two (or species and co-immobilization of two (or more) microorganisms inside the beadmore) microorganisms inside the bead

Chlorella

+

+ Alginate

Azospirillum

= co-immobilization3 mm

Potential use of large beadsPotential use of large beads

• Industry (production of microbial Industry (production of microbial compounds)compounds)

• Wastewater treatment (removal of Wastewater treatment (removal of contaminants)contaminants)

• Agriculture (production of bacterial Agriculture (production of bacterial inoculants)inoculants)

Industry (fermentation)Industry (fermentation)

Microorganisms entrapped in alginate are Microorganisms entrapped in alginate are often grown in large fermentation vats, often grown in large fermentation vats, similar to the vat pictured at left.similar to the vat pictured at left.

The products they produce are harvested,The products they produce are harvested,while the beads remain inside the vat.while the beads remain inside the vat.

Wastewater treatmentWastewater treatment

Something for the future--Something for the future--Large-scale treatment byLarge-scale treatment byimmobilized and co-immobilized and co-immobilized microorganismsimmobilized microorganisms

Agriculture (bacterial Agriculture (bacterial inoculants) before sowinginoculants) before sowing

BeadsBeads

SeedsSeeds

Agriculture (dry alginate beads Agriculture (dry alginate beads sowed in a wheat field)sowed in a wheat field)

BEADS SEEDS

Other applications?Other applications?

The sky is the limit… The sky is the limit…

Use your imaginationUse your imagination

Some unexpected benefitsSome unexpected benefits

• It does not require human energy, let alone paid It does not require human energy, let alone paid energy.energy.

• It is accepted technology, published in most It is accepted technology, published in most scientific journals.scientific journals. (Your “brilliant” paper will not (Your “brilliant” paper will not be rejected on the basis of an untried method.)be rejected on the basis of an untried method.)

• As an environmentally-friendly technology, using As an environmentally-friendly technology, using it will make you look good.it will make you look good.

• Have fun…..Have fun…..