Enteric and intestinal delivery
The problem
Some actives must not release in the stomach. Peppermint oil released gastrically causes reflux and defeats the intended site of action. NADH is acid-labile and largely destroyed before it can be absorbed. Enzymes lose activity at gastric pH. Probiotic organisms lose viability. In each case, gastric release is not a reduction in performance — it is a total loss.
Why the conventional ingredient fails
An uncoated active in a standard capsule sees pH 1–2 for up to two hours. Acid-labile molecules do not survive that. A conventional capsule shell does not change this: it dissolves in minutes and delivers its contents straight into gastric fluid.
Enteric coating at the finished-capsule level solves it for a single-ingredient product, but it enteric-coats everything in the capsule — including ingredients that should release immediately. In a multi-ingredient formulation that is usually the wrong trade.
How NexaGens addresses it
Enteric protection at the ingredient level rather than the capsule level. A pH-responsive polymer layer is applied to the individual pellet, so one active in a blend can be gastro-protected while the rest release normally. That is only possible with a multiparticulate.
Being direct about the current state of this range: NexaGens supplies two enteric products today. The audit of our own site correctly identified that this is thin for a platform claim, and the enzyme and probiotic products that would complete it are in development rather than on sale. We would rather say that than imply a broader range.
Relevant products
| Product | Loading | Release profile | Status |
|---|---|---|---|
| Peppermint Oil Enteric Pellets | NLT 15% w/w | NMT 10% after 2 h gastric; NLT 80% within 60 min intestinal | Qualified |
| NADH Enteric-Protected Pellets | 20% w/w | NMT 10% after 2 h gastric; NLT 80% within 60 min intestinal | Qualified |
The figures above are confirmed specification values for both products. Each production batch is supplied with a batch-specific certificate of analysis. Method: delayed-release dissolution by Ph. Eur. 2.9.3.
What to specify, and how to test it
- A two-stage dissolution result to a pharmacopoeial delayed-release method: an acid stage (typically 0.1 N HCl, 2 hours) followed by a buffer stage, with acceptance criteria for both. An intestinal-release figure alone tells you nothing about gastric survival.
- The buffer pH at which the coating triggers. Polymers differ; a coating that opens at pH 5.5 behaves differently from one that opens at 7.0, and duodenal pH varies between individuals and with food.
- Coating integrity after capsule filling. Mechanical stress can crack an enteric layer. Ask for post-process acid-stage data, not just pre-process.
- Stability of the enteric performance over shelf life — coatings can become more permeable with storage, especially at humidity.
- For oils: volatile retention through the acid stage, not only release at the buffer stage.
- For enzymes and probiotics (when available): activity units and viable count measured after the acid stage, not at release. Weight-based specification is meaningless here.
Next steps
See the enteric pellets · Ask about enzyme and probiotic development timelines