Carrageenan Enteric Soft Capsule Shell for Gelatin-Free Drug Delivery

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Solution Overview

Problem

There is a need for enteric soft capsule technology that does not use gelatin as a film-forming polymer, driven by concerns over Bovine Spongiform Encephalitis in gelatin sources and the requirement for animal-free alternatives, particularly for gastric delivery of active pharmaceutical agents that are sensitive to stomach acidity or have unpleasant tastes/odors.

Innovation Solution

The development of enteric soft capsules using carrageenan as a film-forming polymer, combined with a methacrylic acid copolymer, plasticizers, and other components, which form a stable shell that does not dissolve in gastric fluid but dissolves in intestinal fluid, allowing for targeted drug delivery.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If gelatin is used as a film-forming polymer in soft capsules, then the capsule shell provides good film-forming properties and structural integrity, but the capsule contains animal-derived materials which raises concerns about Bovine Spongiform Encephalitis and is unsuitable for vegetarians and consumers with religious restrictions

Engineering Contradiction:
Improvecapsule shell integrityVSAvoidanimal-derived material concerns
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent changes the chemical composition parameters by replacing gelatin with carrageenan, a plant-derived polysaccharide from red seaweed. This substitution maintains the film-forming capability while eliminating animal-derived materials, thus resolving the contradiction between structural integrity and animal-free requirements

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite capsule shell formulation combining carrageenan with other excipients including fillers, plasticizers, and processing aids. This composite approach allows the plant-based carrageenan to achieve the structural properties previously provided by gelatin, resolving the contradiction while maintaining manufacturing feasibility

Inventive Principle:
Principle #40Composite materials

2Reliability

If conventional enteric coatings are applied to protect acid-sensitive drugs, then the drugs are protected from stomach acidity, but the coating materials often dissolve prematurely or fail to provide controlled release in the intestine

Engineering Contradiction:
Improvedrug protection from acidVSAvoidcoating stability in gastrointestinal tract
Core Design Contradiction:
ReliabilityVSStability of the object's composition

Solution Approach 1:

The patent applies enteric coating materials specifically to the capsule shell surface, creating a localized protective layer with different properties than the bulk shell material. This enteric coating provides acid resistance in the stomach while remaining soluble in the intestine, achieving localized protection where needed without compromising overall capsule functionality

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent uses enteric coating materials as an intermediary layer between the acid-sensitive drug fill and the gastrointestinal environment. This intermediate layer protects the drug from acid degradation in the stomach and releases it in the intestine, resolving the contradiction between protection and controlled release

Inventive Principle:
Principle #24Intermediary (Mediator)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The carrageenan-based enteric soft capsules provide a stable, animal-free delivery system that maintains integrity in acidic environments and releases active ingredients in the intestines, ensuring effective and targeted drug delivery while being transparent and suitable for various fill types.

Implementation Method 1

carrageenan is a natural hydrocolloid, more particularly a polysaccharide hydrocolloid, which is derived from edible red seaweed... The molecules are large and highly flexible and can form helical structures. This gives them the ability to form gels at ambient temperatures.

Methodology Applied
Scientific EffectGel formation: Gel

Implementation Method 2

stable shell that does not dissolve in gastric fluid but dissolves in intestinal fluid, allowing for targeted drug delivery

Methodology Applied
Scientific EffectpH-dependent dissolution:

Data Source

PatentUS10182989B2Non-gelatin enteric soft capsules
Publication Date: 2019.01.22 PATHEON SOFTGELS INC

AI summary

Described herein are pharmaceutical enteric soft capsules that do not contain gelatin as a film-forming polymer. In particular, compositions and methods for manufacturing enteric soft capsules comprising carrageenans as film forming polymers are disclosed.