Interface-Mediated Transdermal Patch Layers for Stable Drug Loading
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Transdermal therapeutic systems (TTS) face challenges with increased active agent loading leading to crystallization, coalescence, and fluctuating drug release due to large droplet sizes in solvent-based biphasic systems, necessitating improved stability and consistent drug delivery.
Innovation Solution
A transdermal therapeutic system with a self-adhesive layer structure containing a dried biphasic layer, comprising an outer phase of polymer or polymer mixture and an inner phase with an active agent, stabilized by an interface mediator with a kinematic viscosity of 10 cSt to 100 000 cSt, ensuring uniform dispersion and reduced droplet size for continuous drug delivery.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If the active agent concentration in the TTS matrix is increased, then the loading capacity is improved, but crystallization of the active agent occurs during storage
Solution Approach 1:
The patent employs a biphasic system consisting of a polymer phase and an oil phase with dispersed active agent. This composite structure allows high active agent loading in the oil phase while the polymer phase provides structural stability and prevents crystallization during storage, thus resolving the contradiction between loading capacity and system stability.
Solution Approach 2:
The patent modifies the physical state and distribution parameters of the active agent by dispersing it in the oil phase rather than the polymer phase. This parameter change prevents crystallization while maintaining high loading capacity, as the active agent remains solubilized in the liquid oil phase even at high concentrations.
2Quantity of substance
If the active agent concentration in the biphasic system is increased, then the loading capacity is improved, but coalescence of the dispersed phase occurs
Solution Approach 1:
The patent introduces surfactants as intermediary substances at the interface between the polymer phase and oil phase. These surfactants reduce interfacial tension and prevent coalescence of the oil droplets, allowing high active agent concentration in the dispersed oil phase while maintaining phase stability throughout the administration period.
3Ease of manufacture
If large active agent-containing droplets are used in the biphasic layer, then the manufacturing process is simplified, but drug release fluctuates and dose dumping occurs
Solution Approach 1:
The patent employs mechanical vibration or ultrasonic treatment during the manufacturing process to disperse the active agent-containing oil phase into fine, uniform droplets within the polymer matrix. This mechanical energy input creates a stable dispersion with consistent droplet size distribution, ensuring reliable and fluctuation-free drug release while maintaining ease of manufacture through a straightforward coating process.
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 system provides long-term stability and consistent therapeutically effective drug delivery for 1 to 7 days with reduced fluctuation, meeting convenience and skin tolerance requirements while being cost-effectively manufactured.
Implementation Method 1
an interface mediator with a kinematic viscosity of 10 cSt to 100 000 cSt
Implementation Method 2
transdermal administration of a systemically active agent
Data Source
AI summary
The present invention relates to aransdermal therapeutic system for the transdermal administration of a systemically active agent having a self-adhesive layer structure. The transdermal therapeutic system includes (A) a backing layer, and (B) a dried biphasic layer. The dried biphasic layer has (a) an outer phase having a composition comprising 75% to 100% of a polymer or polymer mixture, and (b) an inner phase having a composition that includes at least one active agent. The inner phase forms dispersed deposits in the outer phase, with the dried biphasic layer including (c) from 0.1% to 3.5% of an interface mediator other than silicone oil, with the interface mediator having with a kinematic viscosity of from 10 cSt to 100 000 cSt at 25° C.