Skygel™ - 400 LVPH

Rheological Additive for Pharmaceutical

General Description

Skygel™ Thickeners are colloidal, inorganic mineral thickeners which are essentially inert and non swelling in aqueous applications. When dispersed in water, they display unique Thixotropic properties that are useful in a variety of aqueous applications. Modest cost, high performance and virtually universal compatibility mean that they can often replace, or partially substitute for expensive imported thickeners while offering equivalent performance. Skygel™ thickeners are Hydrated Magnesium Aluminum Silicate base Pharmaceutical grade rheological additive refined from natural mineral clay. It has been developed as a high purity, fast hydrating stabilizer for aqueous systems.

The therapeutic value of Attapulgite has been known for the last two centuries. However, scientific research into this amazing mineral’s therapeutic properties began in earnest in the 1950’s. It was discovered that specific thermal activation of this mineral could augment its adsorptive capacity and that different desirable properties could be developed.

In pharmaceutical applications, their main use is in the field of intestinal medicine for the treatment of diarrhea because of their high sorptivity for toxins. Other uses include suspending, thickening, and tablet binding.

Skygel™ in Pharmaceutical Applications

In Antidiarrheal Medications

Skygel™ pharmaceutical grade of Attapulgite is utilized in the field of intestinal medicine, primarily in products for the treatment of diarrhea. It has a natural value here because of its high sorptivity for toxins, plus its ability to build bulk in the system. Much of the pain and discomfort of diarrhea is due to the action of the toxins. When toxins are effectively adsorbed, as they are on Skygel™ Attapulgite, there usually is a dramatic cessation of distress and cramping, followed by a much more rapid improvement that can be achieved by other absorbent-type preparations.

Therapeutic compositions containing Skygel™ have been prepared and clinically tested. These were aqueous systems containing upto 10 % of Skygel™ clay plus other functional ingredients such as antibiotics, pectin etc. If a dry preparation is desired, because of its inherent binding ability Skygel™ grades may be compressed to form tablets. 

The superior properties of Skygel™ as an adsorbent for bacteria and toxin, as compared with those of kaolin, have lead to their increasing use in the formulation of intestinal adsorbent preparations. Skygel™ will absorb many times its weight of water and most other liquids, while kaolin only absorbs about half of its weight. This high absorbency helps to build bulk in the system.

The superiority of Skygel™ over kaolin as an adsorbent is mainly due to the fine particle size and porosity of Attapulgite, which result in a highly effective surface area for sorption to take place. The surface area of the Skygel™ is many times greater than that possessed by kaolin. The superior adsorptive properties of the Skygel™ over kaolin may be observed as Skygel™ is far better in their ability to adsorb methylene blue. Skygel™ is 3 to 4 times superior to kaolin in their abilities to adsorb this dye. Methylene blue is the standard dye that the British Pharmacopoeia uses to measure the absorptivity of clays.

Other Pharmaceutical Applications

Suspending: - Skygel™, when adequately dispersed, adds considerable viscosity to liquids. Because of its pharmaceutical acceptance, this makes it ideal for suspending materials in certain systems or for thickening other systems.

Stabilizing water-in-oil and oil-in-water emulsions: - Skygel™ has the ability to stabilize both types of emulsions. The use of Skygel™ enables the formulator to decrease the amount of surface active agents since it provides emulsions with much better stability than often is encountered in normal systems.

Conditioning of Sediments: - In liquid preparations, where sedimentation tends to occur, resulting in a hard cake, the addition of 3 to 4 % Skygel™ in the dispersed state not only tends to slow down sedimentation, but also conditions the sediment which is formed so that it is much easier to disperse.

Sorptive Agent: - When dry pharmaceutical compositions are desired, Skygel™ serve well as carriers for liquids incorporated into the formulation. Because of its type of thermal activation, Skygel™ shows higher sorptive capacity and will absorb 30 to 40 % liquid by weight in such compositions and still remain semi-solid.

Tableting: - Skygel™ helps to serve as a binder when mixed with other dry ingredients which are to be tabulated. It compacts very easily.

Comments on Pharmaceutical Formulations:

Skygel™ has a bland taste similar to that of other silicate minerals utilized in pharmaceutical preparations. Consequently, the Skygel™ containing formulations are generally sweetened and/or flavored. Systems containing Skygel™ is essentially odorless.

Skygel have a creamy color in liquid preparations, and systems containing them have been dyed red, purple and green with considerable success. Standard FDA coloring materials are used in these preparations.

Although micro-organisms are not capable of utilizing the Skygel™ as nutrients for growth purposes, preparations in which they are used generally contain traces of material which is capable of supporting microbial action. Most standard preservatives have been used successfully with Skygel™ containing compositions.

Toxicity studies on Skygel™ have revealed that it lacks any degree of toxicity. Studies on acute oral toxicity, chronic oral toxicity, skin irritation and eye irritation have been carried out with negative results. Unfortunately, such results do not allow manufacturers of compositions based on the Skygel™ to assume non-toxicity. They are still obligated to clinically test such preparations because of the possibility of interactions.

In certain instances, pharmaceutical compounds used with Skygel™ have been found to be incompatible. For example, pectin plus Skygel™ eventually goes to an irreversible gel in water systems. This can be overcome by adjusting the pH of the system with phosphoric acid to the region of 4.5 to 5.5. Certain amino phenols and nitro phenols also interact with Skygel™ to give undesirable off-colored products.

Properties in Formulation

Various properties make Skygel™ the preferred rheological additive for pharmaceutical preparations

• Electrolyte stability: sodium salts are tolerated. Higher concentrations of other soluble salts may affect the efficiency of Skygel™

   

• Surfactant compatibility: Skygel™ can be used with anionic, nonionic and amphoteric surfactants.

   

• Temperature stability: Products formulated with Skygel™ remain stable in the heat and cold.

   

• Opacity: Skygel™ forms milky, turbid gels. Hence, gives very high level of opacity.