Fluidic Device Sweat Meniscus Stabilization via Pressure Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for evaluating deodorant efficacy, particularly antiperspirants, face challenges in stabilizing the sweat meniscus at the junction point with deodorant channels, leading to unstable experimental conditions and inability to effectively assess various dosage forms and antibacterial products.
Innovation Solution
A system comprising a fluidic device with a pressure actuator, flow meter, and closed-loop controller maintains a stable zero flow rate, allowing precise control of sweat meniscus positioning and contact with deodorant products, enabling evaluation of deodorant efficacy across different forms and antibacterial properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a syringe pump is used to control sweat flow rate, then the flow rate can be controlled, but the stabilization time is too long (several minutes) to stabilize the meniscus position at the channel junction
Solution Approach 1:
The patent replaces the mechanical syringe pump system with a pressure-controlled system. A pressure controller adjusts the pressure in the sweat reservoir to control sweat flow, eliminating the long stabilization time of syringe pumps. The pressure system responds much faster to stabilize the meniscus at the channel junction within seconds rather than minutes.
Solution Approach 2:
The patent changes the control parameter from direct mechanical displacement (syringe pump plunger position) to pressure control. By regulating pressure in the sweat reservoir, the system achieves rapid meniscus position stabilization. The pressure controller can quickly adjust pressure to maintain zero flow rate and stable meniscus position at the channel junction.
2Stability of the object's composition
If the fluidic connection is cut off using a stopcock, then the meniscus can be isolated, but the location of reaction with antiperspirant product cannot be controlled
Solution Approach 1:
The patent replaces the stopcock mechanical cutoff system with continuous pressure control. Instead of isolating the meniscus by cutting fluidic connections, the pressure controller maintains zero flow rate to stabilize the meniscus in place. This allows the meniscus to remain stable at the channel junction while enabling controlled introduction of antiperspirant product for reaction.
3Strength
If rigid material channels are used, then the structure is stable, but the meniscus moves freely and cannot be stabilized at the junction point
Solution Approach 1:
The patent replaces mechanical constraints (rigid channel structures attempting to physically constrain the meniscus) with pressure control. The pressure controller actively regulates sweat flow to maintain the meniscus at the desired position at the channel junction. This works with rigid channels while achieving meniscus stability through pressure regulation rather than mechanical constraint.
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 stabilizes the sweat meniscus at the channel orifice, allowing for reliable evaluation of deodorant efficacy, including antibacterial properties, and effectively assesses various deodorant forms without time constraints, improving the reproducibility and reliability of experimental results.
Implementation Method 1
a pressure actuator (6) capable of imposing the pressure of a gas phase inside said reservoir
Implementation Method 2
The liquid phase, i.e. the sweat (5), and the gas phase are separated by an interface (12) at a height h1. The main channel (4) has an orifice (11) formed by its wall at another end at a height h2, the height h1 being strictly different from h2
Implementation Method 3
the flow meter (7) being capable of measuring the flow rate of the main channel (4) and of transmitting information about said flow rate to the controller (8), the controller (8) being capable of transmitting control information to the pressure actuator (6)
Data Source
AI summary
A process for evaluating efficacy of a deodorant product includes: introducing sweat into a main channel formed in a fluidic device satisfying particular requirements; measuring a flow rate of the sweat in the main channel and transmitting the flow rate to a controller; imposing a pressure set point on the pressure actuator by closed-loop control so the flow rate of the sweat in the main channel is controllable; contacting the sweat and a deodorant product and reacting the sweat and the deodorant product with each other, the deodorant product being provided in a particular manner, wherein while the sweat and the deodorant product react with each other, the flow rate of the sweat in the main channel is maintained at substantially zero; and determining at least one of a physicochemical parameter and a biological parameter of a product of the reaction between the sweat and a the deodorant product.