Microfluidic Drug Delivery System for Inner Ear

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current drug delivery methods for inner ear disorders are inefficient and lack precise control, particularly for complex molecules, due to the blood-labyrinth barrier and anatomical challenges, leading to unpredictable drug distribution and significant side effects.

Innovation Solution

A microfluidic drug delivery system utilizing a recirculating stream of perilymph through a catheter, with a micropump and microvalves for controlled delivery of drugs directly to the cochlea, allowing for long-term, programmable, and sequenced delivery of multiple molecules with minimal side effects.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If systemic drug delivery is used to treat inner ear disorders, then drugs can reach the inner ear, but significant systemic side effects occur due to high doses required

Engineering Contradiction:
Improvedrug concentration in inner earVSAvoidsystemic side effects
Core Design Contradiction:
Quantity of substanceVSObject-affected harmful factors

Solution Approach 1:

The invention segments the drug delivery system into separate pathways: one for drug administration and another for fluid recirculation. The catheter is divided into multiple lumens that allow independent control of drug flow and perilymph flow, enabling localized drug delivery without systemic distribution

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The recirculating perilymph acts as an intermediary carrier that transports drug molecules from the injection site throughout the inner ear fluid system. This mediator enables uniform drug distribution within the confined inner ear space without requiring high systemic doses

Inventive Principle:
Principle #24Intermediary (Mediator)

2Object-affected harmful factors

If transtympanic perfusion is used for drug delivery, then systemic side effects are reduced, but drug delivery to the inner ear is unpredictable due to anatomical barriers

Engineering Contradiction:
Improvesystemic side effectsVSAvoiddrug delivery predictability
Core Design Contradiction:
Object-affected harmful factorsVSReliability

Solution Approach 1:

The invention extracts the drug delivery process from the unpredictable transtympanic route and places it directly into the inner ear perilymphatic space. By injecting drugs directly into the perilymph through the cochlear catheter, the system bypasses the round window membrane and middle ear anatomical variations that cause unpredictable delivery

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The recirculating pump system provides feedback control by continuously monitoring and adjusting the perilymph flow rate to maintain optimal drug distribution. The system can be programmed to deliver drugs at specific rates and intervals, ensuring predictable and reliable therapeutic concentrations

Inventive Principle:
Principle #23Feedback

3Speed

If rapid drug delivery is used to achieve therapeutic concentrations, then treatment effectiveness is improved, but drug distribution becomes unpredictable and concentrated in certain areas

Engineering Contradiction:
Improvedrug delivery rateVSAvoiddrug distribution uniformity
Core Design Contradiction:
SpeedVSReliability

Solution Approach 1:

The invention implements continuous recirculating flow of perilymph through the cochlea and vestibule, ensuring that drug molecules are continuously distributed throughout the entire inner ear fluid system. This continuous action prevents localized concentration and ensures uniform therapeutic distribution

Inventive Principle:
Principle #20Continuity of useful action

Solution Approach 2:

The system uses periodic pumping cycles to recirculate perilymph and drug molecules through the inner ear structures. The programmable pump delivers drugs in controlled intervals, allowing for both rapid initial delivery and subsequent distribution phases

Inventive Principle:
Principle #19Periodic action

4Quantity of substance

If complex molecules are delivered systemically, then they cannot cross the blood-labyrinth barrier, but delivery to the inner ear is blocked

Engineering Contradiction:
Improvecomplex molecule deliveryVSAvoidbarrier penetration
Core Design Contradiction:
Quantity of substanceVSReliability

Solution Approach 1:

The invention extracts complex drug molecules directly from the circulation and delivers them into the perilymphatic space, bypassing the blood-labyrinth barrier entirely. This direct injection method allows large proteins, peptides, and other complex molecules to reach their targets without needing to cross the protective barrier

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The perilymph serves as an intermediary medium that receives complex molecules directly from injection and transports them to their targets within the inner ear. This intermediary pathway eliminates the need for the molecules to cross the blood-labyrinth barrier

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

Enables precise and efficient delivery of drugs to the inner ear, reducing systemic side effects and maintaining therapeutic concentrations over extended periods, suitable for treating hearing loss and other inner ear disorders.

Implementation Method 1

a micropump and microvalves for controlled delivery of drugs directly to the cochlea

Methodology Applied
Scientific EffectPumping: Pump

Implementation Method 2

a micropump and microvalves for controlled delivery of drugs

Methodology Applied
Scientific EffectValve control: Valve

Data Source

PatentEP2670456B1Drug delivery apparatus
Publication Date: 2019.12.18 THE CHARLES STARK DRAPER LABORATORY INC
  • EP2670456B1 patent drawingFigure 1
  • EP2670456B1 patent drawingFigure 2A~2B
  • EP2670456B1 patent drawingFigure 3A

AI summary

An implantable drug delivery apparatus for delivering a drug into a bodily fluid in a bodily cavity of a patient over a period of time includes a drug supply reservoir (24) to supply drug into a delivery channel (1005) and an actuator for delivering the drug to a predetermined location in the bodily cavity of the patient, such as, for example, a cochlea of a human ear. The drug is loaded into the delivery channel while producing substantially negligible flow at an outlet (1010) of the delivery channel.