Oral Dissolving Film (ODF) provides an alternative delivery method from capsules and tablets. They require no additional water and are not subject to breaking, leaking, melting. They are safe to travel with, maintain a long shelf-life and maintain freshness until consumed. ODF’s provide a delivery system that maintains high bioavailability.

In this article, I will explain how we formulate and produce our Oral Dissolving Film strips.

Formulation:

Oral Dissolving Films contain:

1. Active Ingredients
2. Polymer(s)
3. Plasticizers
4. Saliva Stimulating Ingredients
5. Color, Sweetener, Flavor, other.

Active Ingredients take up 1%-30% of the film. These are entirely dependent on the films we are producing. Ideally, they are water, oil, or alcohol based (or dissolvable). In order to achieve content uniformity, and produce a smooth film, the actives must dissolve. Since Lionheart Enterprises is a nutraceutical producer, we cannot produce with OTC or RX ingredients.

Polymer(s) provide the structure and strength of the film. We use pullulan (a naturally derived polymer) and occasionally cellulose is required for an added strengthening. The Polymer consists of 30-60% of the final weight of the film.

Plasticizers take up 0.2%-20% of the film depending on the formulation we are producing. Some of the plasticizers we have used are carrageenan, PEG400, glycerin. Plasticizers provide structure, tensile strength, etc. to the film.

Saliva Stimulating ingredients such as citric acid are used to not only simulate saliva which promotes fast disintegration but is also used to mask bitterness from the active ingredients. Typically, we incorporate less than one percent of citric acid to accomplish these goals.

Color, Sweetener, Flavor, other we utilize natural color such as turmeric, spirulina, annatto seeds, etc. to add color to some of our formulations. Stevia (RebM) is used as a sweetener to provide a natural sweetening to the film. Various flavors (almost always natural, organic flavors are utilized). We have found the most success with mint, citrus, and berry/fruit flavors. Combining flavors with stevia and citric acid have produced tasty oral strips. We also find that adding color that matches the flavor provide a better experience for the user.

There are also certain formulas that require a surfactant to fuse oil and water components, such as when we produce cannabinoid infused strips. In those situations, a lecithin is used.

Preparation and Blending

Lionheart Enterprises utilizes the Solvent-Casting Method of film production. In this method we combine all ingredients into one slurry before casting it into a film.

We take special care to combine the ingredients in a way the promotes content uniformity, namely, we dissolve active ingredients or bring them to temperature prior to mixing them with other ingredients. This multi-step process promotes content uniformity and reduces possibilities for issues down the line.

Once all ingredients are mixing and blending, we add vacuum to the homogenizer which removes air pockets in the film. Our vacuum homogenizer reduces atmospheric pressure to -0.009MPA. This process allows us to produce oral film without excess air bubbles in the film. This process helps us produce a smooth, consistent, uniform oral film strip.

Casting, Cutting and Packing

Once the slurry has been sufficiently blended and vacuumed. We transfer (little by little) the slurry, from the homogenizer to the Film Making Machine. This machine looks similar to a pizza oven. However, instead of a tray full of pizza’s, there is a roll of PET 35cm wide that feeds the wet slurry through the oven. At the beginning end of the oven two large rollers are positions roughly 0.5mm away from each other. When we add the slurry to the feeding station, the rollers are engaged to feed the slurry though, onto the PET and through the oven.

The oven temperature is set to somewhere between 70-80 degrees Celsius. The speed is then set and the slurry if feed though to allow it to dehydrate to the desired consistency. We are looking for a film that is sufficiently dry, but not too dry that the film breaks and cracks before packaging. 10% humidity on the strip is an ideal achievement.

As it comes out of the oven we check for consistency, thickness, humidity, and adjust temperature and speed of rolling as needed.

Once the last of the slurry has had its chance to go through the oven, then next step is cutting and packaging. Our packaging machine will separate the film from the PET, cut the film down to 2.5cm width strips and chop the film to the desired length. Our strips typically are cut to 3cm-5cm lengths. The length is typically determined based on the amount of active ingredient we want in the finished strip.

Immediately after cutting the cut strip is placed in its pouch and sealed for freshness. The process from start to finished, packaged film takes place all with a 24 hour period of time. Once packed in their individual pouch we can then pack pouches into retail ready packaging and ship off to the customer.

Conclusion

There are many variables we take into account when formulating and producing Oral Dissolving Film. Active ingredient type and amounts are what drive decisions around adjustments to formulation and production.

As a leading ODF manufacturer for dietary supplements we are experienced and well suited for your project. Contact us to discuss your ODF project with us today.