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2004 Pformulate.
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Carrageenan
1] Description:
Naturally occurring family of polysaccharides derived from red sea weed.
Three basic types are available: Kappa, iota and lambda which differ in the
number and location of sulfate ester substitution. These are available in a
variety of grades that provide a wide range of rheology properties for gelling
and viscosifying preparations.
None of the
carrageenan types are stable in acid. Hydrolysis in low pH systems is
accelerated by heat. In the gel state, kappa and iota carrageenans are stable
above a pH of 3.8.
2] Properties:
| IOTA Carrageenans |
Viscosity
|
Gel Type |
Solubility |
Reactivity |
| Gelcarin® GP-379NF |
High
Thixotropic |
Elastic
Medium strength
Forms strongest gel with calcium ions |
hot water soluble
Sodium salt soluble in cold water.
Calcium salt cold water swellable to
form a thixotropic dispersion. |
Polyol and protein reactive |
| SeaSpen® PF |
Medium
Thixotropic |
Elastic
Weak strength
Forms strongest gel with calcium ions |
cold water soluble,
delayed gel formation |
|
| KAPPA Carrageenans
|
Viscosity
|
Gel Type
|
Solubility
|
Reactivity |
| Gelcarin® GP-812NF |
Low
|
Brittle
Strong strength
Forms strongest gel with potassium ions |
Hot water soluble
Sodium salt soluble in cold water. Potassium,
calcium and ammonium salt cold water swellable. |
|
| Gelcarin® GP-911NF |
Low |
Brittle
Firm strength
Forms strongest gel with potassium ions |
Hot water soluble
Partially soluble in cold water
Sodium salt soluble in cold water. Potassium,
calcium and ammonium salt cold water swellable. |
Polyol and protein reactive |
| LAMBDA Carrageenans
|
Viscosity
|
Gel Type
|
Solubility
|
Reactivity |
| Viscarin® GP-109NF |
Medium
|
Non-gelling
|
Hot water soluble
Partially soluble in cold water
|
Polyol and protein reactive |
| Viscarin® GP-209NF |
High |
Non-gelling |
Hot water soluble
Partially soluble in cold water
|
Polyol and protein reactive |
| Kappa/Lambda carrageenans mix |
Viscosity
|
Gel Type
|
Solubility
|
| Viscarin®
GP-328NF
|
Medium-high
|
weak
|
Hot water soluble
|
3] Applications:
| Gelling agent
|
Kappa and iota types set up gel
structures that are thermally reversible.
Kappa creates a stiff, strong gel, useful in
applications that require shape retention such as otic, vaginal, suppository,
and controlled release dosage forms.
Iota gels are flexible, elastic gels which when
broken will reheal into a gel structure, useful in film formation or spreading
applications
Genugel and Genuvisco are used for
softgellingin capsules |
| Suspensions |
Gelcarin® GP-379NF for suspensions at
levels of 0.3 - 1.0%.
SeaSpen® PF is useful for suspensions and reconstitutable suspensions at
levels of 0.5 - 1.0%. Delayed gelling properties enable ingredient
distribution in the system before a gel structure is established. After set
up of the gel a stable suspension of drug is obtained. |
| Viscosifying agent |
Lambda carrageenans such
Viscarin® GP-109NF and Viscarin®
GP-209NF are good viscosifying agents
at levels of 0.1 - 1%.
Viscosity can be controlled by the use of metal ions.
|
| Topical gels, creams and lotions |
All carrageenans have excellent water
binding capabilities which are useful in topical dosage forms.
They are non-sticky, and provide pleasant
skin feel.
Gelcarin® GP-379NF for creams at levels
of 0.3 - 1.0%.
Gelcarin® GP-812NF for gels at levels of 0.3 -
1.0%.
Viscarin® GP-109NF and Viscarin®
GP-209NF for creams and lotions at levels
of 0.1 - 1%.
Viscarin® GP-328NF for creams and
lotions at levels of 0.7 - 1.2%. Excellent for maintaining emulsions.
SeaSpen® PF for lotions and creams at levels
of 0.5 - 1.0%.
|
4] Suppliers:
Need a supplier? Submit in Excipients
Express!!!
5] References:
Gelcarin â and Viscarinâ Carrageenan,
NF, Technical Bulletin online at www.avicel.com
pformulate/01/25/2004
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