Alginate capsules (hard and soft capsules), the technology that can replace gelatin capsules.

1. Alginate capsule
Introduction:
In the manufacture of pharmaceuticals, encapsulation refers to a range of
techniques used to enclose medicines in a relatively stable shell known as a capsule,
allowing them to, for example, be taken orally or be used as suppositories. The two
main types of capsules are:
Hard-shelled capsules, which are normally used for dry, powdered ingredients or
miniature pellets (also called spheroids that are made by the process of Extrusion and
Spheronization - Spheronization is a trade mark of Caleva Process Solutions) or
tablets;
Soft-shelled capsules, primarily used for oils and for active ingredients that are
dissolved or suspended in oil.
Alginate hard capsule
Overview:
Novel hard capsules are made of alginate which is derives from marine algae. It
is safer for consumer (all ingredient of the capsule are non-animal based materials),
more stable during shelf life (stable in boiling water) and cheaper than gelatin
capsules. The alginate hard capsules can be designed for Active Pharmaceutical
Ingredient with gastric solubility, enteric solubility or colon solubility easily. The
alginate hard capsules are suitable for different kinds of API. Moreover, it can be used
in the field of food and industry due to its perfect safety, stability and low-costing.
Photo of samples are showing below (upper side is gelatin shell, bottom side is
alginate shell).

2. Specialty:
※Alginate, the major material of the shell, is extracted from algae which is
cheap and used in food and drug for many years. It is full of human necessary
microelement and used as health food in many countries. Moreover, alginate can
absorb heavy mental ion and free radical from human body with anti-cancer activity.
※ The capsule is very stable. There is no observable change on the shell of
capsules after storage for three months under 50℃ and 80% RH.
※ The making process of alginate hard capsules is similar to gelatin hard
capsules.
※ The release of the API can be adjusted by different way which is suitable for
different API target to different location.
※ Alginate is chemical inert and can not react with the API in the core
chemically or physically.
※ Alginates shell with little water content has antibiotic property which means it
is no need or less need for preservatives.
※ All ingredient of the capsule are non-animal based materials which is suitable
for muslim and vegetarian consumer, and there is no danger from animal infectious
disease.
Alginate soft capsule
Appearance:
Spherical, smooth and uniform with diameter of 1-10 mm (other shape and size
other than above are available), oil based core (non-water soluble liquid) within the
capsule comprise at least 80% by weight of the capsule, shell of the capsule is alginate
gel. Diagram is showing below.
A example of alginate capsules making process is showing below.

3. Samples picture (colored samples and non-colored samples)
Handmade samples and dissected samples (suspension with high solid loading in
the capsules)

4. Overview:
Patent (publication number: CN101564667, other patents will be published soon)
of alginate soft capsules used novel material and novel technology. It is safer for
consumer (all ingredient of the capsule are non-animal based materials), more stable
during shelf life (stable in boiling water) and cheaper than gelatin soft capsules (cost
of the capsules is less than one third of gelatin soft capsules). Shell of the capsules
will turn into alginic acid in stomach under the effect of gastric acid which can protect
the Active Pharmaceutical Ingredient in the core from decomposing by gastric acid. In
intestine, shell of the capsules will turn into soluble sodium alginate or potassium
alginate when meet with sodium or potassium ion then release the API in the core(an
other way of API releasing is that crosslinked alginate shell will de-crosslinked when
react with bicarbonate excrete by pancreas or gallbladder). Detailed releasing profile
is related with the shell thickness, alginate molecular weight and other facts. The
techniques are suitable for different kinds of API soft capsule. Moreover, it can be
used in the field of food and industry due to its perfect safety, stability and
low-costing.
Specialty:
※Alginate, the major material of the shell, is extracted from algae which is
cheap and used in food and drug for many years. It is full of human necessary
microelement and used as health food in many countries. Moreover, alginate can
absorb heavy mental ion and free radical from human body with anti-cancer activity.
※ The capsule is very stable. A tested sample with volatile flavor dissolved in
the core maintains its flavor concentration after storage for one year and can be tasted
its flavor after three years. There is no observable change on the capsules after storage
for three months under 50℃ and 80% RH.
※ Shell of the capsule comprise at most 15% by weight of the capsule which
can improve the loading capacity of the API within the capsule.

5. ※ The making process of alginate capsules is similar to dripping pills which
have applied in pharmaceutical industry for long time. It is very easy to produce
alginate capsules with different diameter just change the diameter of the dropper.
Capsules with diameter less than 2mm, or even 0.5mm, can be made using a nozzle
instead of dropper. Capsules with diameter more than 7mm, or even 12mm, can be
made using a quantified pump instead of dropper.
※ The release of the API can be adjusted by different way which is suitable for
different API target to different location. The capsule is not soluble in stomach and
water which means it is suitable for non-acid-proof API or complex mixture API with
hygroscopic ingredient.
※ Alginate is chemical inert and can not react with the API in the core
chemically or physically.
※ Alginate capsules with suspension inside are easier to produce which has a
solid content more than 80%.
※ Almost all API in powder (regardless of its particle size and solubility in
water/oil) can be encapsulated in alginate capsules.
※ Alginates shell with little water content has antibiotic property which means it
is no need or less need for preservatives.
※ All ingredient of the capsule are non-animal based materials which is suitable
for muslim and vegetarian consumer, and there is no danger from animal infectious
disease.
※ Due to its special thermal and humid stability, alginate capsules can be used
as novel product for soft capsules in the field of drug, food (especially for baked food),
agriculture (especially for soft capsules for plant nutrition and animal food) and
industry (such as bacterium capsules for health food or water pollution treatment
usage).
※ There is no need for expensive equipment, organic solvent and toxic material
during large-scale produce. The making-process is environment friendly and no
rubbish produced. There is no need for any equipment if daily yield less than 10
million capsules. The cost of production line for more than 100 million capsules per
day is less than 100,000 USD. Soft gelatin encapsulation machine with rotating mould
which is popular nowaday for soft capsules mass production can be applied for
alginate capsules production with slightly adjustment.
File update time: May. 2012
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