Transdermal Patch Ion-Pair Melting Point Depression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional drug patches for risperidone have insufficient skin absorbability due to the barrier function of the skin's horny layer, and existing methods to enhance permeability have not achieved sufficient therapeutic efficacy.
Innovation Solution
A patch comprising a drug, a melting point lowering agent, and an adhesive base, where the melting point lowering agent, such as acetic acid or sodium acetate, forms an ion-pair with the drug to lower its melting point by 60° C or more, improving skin absorbability and stability, and further enhanced with absorption enhancers like lauric acid diethanolamide and propylene glycol monolaurate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If risperidone is blended in a conventional patch adhesive layer, then the patch structure is simple, but the skin absorbability is insufficient
Solution Approach 1:
The patent changes the physical and chemical parameters of the adhesive layer by incorporating skin permeation enhancers (fatty acids, solvents) and later ionic liquids, which fundamentally alter the layer's properties to enable sufficient drug permeation through the horny layer while maintaining patch structure
Solution Approach 2:
The patent creates a composite adhesive layer composition combining the adhesive base with skin permeation enhancers (fatty acids, solvents) and subsequently with ionic liquids, forming a multi-functional composite material that simultaneously provides adhesion and enhanced drug permeation capabilities
2Reliability
If a skin permeation enhancer such as fatty acids or solvent such as propylene glycol is added to increase skin absorbability, then the skin absorbability is improved, but the patch composition complexity increases
Solution Approach 1:
The patent merges the functions of multiple components (adhesive base, skin permeation enhancers, ionic liquids) into a unified adhesive layer composition, where the ionic liquid serves both as a permeation enhancer and a functional additive, reducing the need for separate components
3Reliability
If an ionic liquid is formed between an ionic drug and counter ion to enhance skin absorbability, then the skin absorbability is improved, but the melting point control and formulation stability become more difficult
Solution Approach 1:
The patent systematically adjusts the molecular structure of ionic liquids (selecting different counter ions like lidocaine, lidocaine hydrochloride, benzocaine) to control the melting point within a specific range (below room temperature or slightly above) and optimizes the drug-to-counter ion ratio to achieve both enhanced permeation and formulation stability
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 patch achieves significantly improved skin absorbability and sustainability of drug efficacy, allowing for effective transdermal administration of risperidone without digestive or hepatic metabolism, simplifying administration and improving compliance in schizophrenia patients.
Implementation Method 1
the melting point lowering agent, such as acetic acid or sodium acetate, forms an ion-pair with the drug to lower its melting point by 60° C or more
Implementation Method 2
lowering agent to lower the melting point of the drug in an adhesive layer
Implementation Method 3
to increase the skin absorbability of risperidone in a percutaneous administration method using a patch
Data Source
AI summary
The problem of the invention is to provide a drug-containing patch which is very favorable in percutaneous absorbability and is excellent in sustainability of the drug efficacy, that is, the drug-containing patch having a sufficient percutaneous absorbability and effect sustainability in a degree to be actually used for therapy of patients. The problem is solved by a patch comprising a drug, a melting point lowering agent and an adhesive base.