Traditional capsules made from gelatin are said to begin disintegrating immediately, with complete disintegration observed within approximately 15 minutes. The new study found that the DRcaps began release in a mean time of 52 minutes after ingestion and completely released the ingredients in a mean time of 72 minutes after ingestion.
The study was designed to investigate the in vivo behavior of DRcaps using a scintigraphic method to assess the gastrointestinal transit and release of the contents from capsules based on the images obtained. Gamma scintigraphy is an established technique in which a radio label is swallowed and the disposition in the gut is photographed externally over time. The study participants consumed a light breakfast approximately 30 minutes prior to dosing a DRcaps capsule containing 300mg of lactose, 10mg of which was radiolabelled.
The scintigraphic study revealed that the capsules actually began releasing at 52 minutes when they were about to leave the stomach. “That is 45 minutes later than an immediate release capsule and means that the contents of the capsules would often be released in the intestines – where probiotics and enzyme ingredients are most effective,” said Dr Keith Hutchison, senior VP, Research and Development, Capsugel.
For the majority of subjects, complete release was said to take place in the intestine.
“The results from this human clinical study provide scientific evidence of DRcaps capsules’ acid-resistant and delayed-release performance to give confidence that DRcaps capsules are an excellent choice for delivery of acid-sensitive ingredients,’ said Dr Hutchison.
The new study’s findings have not been published in a peer-review journal but the company will prepare a “thorough white paper”, said a spokesperson.
DRcaps were launched at the 2011 Expo West show in Anaheim, and are made from hydroxypropyl methylcellulose (HPMC). The spokesperson told us that the capsules are “selling very well”.
The capsules could also help cut production costs and time, said the company, since no coating step is required: The capsules do not require the application of chemical coatings to protect ingredients, mask tastes, or postpone the release of active ingredients, said Capsugel.
The capsules also boast a low moisture level, said Capsugel, making them attractive to ingredients such as probiotics. Indeed, in 50% relative humidity, the capsules have a moisture level of 4 to 6%, compared with 12 to 14% for gelatin.
“The special release properties built into the capsules provide the choice of a vegetarian product for fast product launches, and still provide acid-protection and delayed release,” added Dr Hutchison.