Solid Bead Formation via Droplet Ejection and Solvent Extraction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for producing solid beads of uniform size, such as microfluidic circuits, face challenges in generating large volumes of particles efficiently.

Innovation Solution

An apparatus comprising liquid droplet generators and flow channels, where droplets are ejected with a non-zero initial velocity into a second liquid, allowing for rapid production of uniformly sized solid beads by solvent extraction, with features like piezoelectric components, flow rate control, and monitoring systems to ensure consistent bead formation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If microfluidic circuits are used to produce solid beads, then manufacturing precision and uniformity of size are improved, but productivity is worsened due to difficulty in producing large volumes

Engineering Contradiction:
Improveuniformity of bead sizeVSAvoidvolume of beads produced
Core Design Contradiction:
Manufacturing precisionVSProductivity

Solution Approach 1:

The apparatus segments the bead production process into two independent streams: a first liquid carrying droplet generators and a second liquid flowing through channels. This segmentation allows multiple droplet generators to operate simultaneously on different segments of the second liquid, enabling large-volume production while maintaining the precision of individual droplet processing.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The invention transitions from two-dimensional microfluidic channel flow to a three-dimensional spatial arrangement where droplet generators are positioned above and eject droplets onto a flowing liquid stream. This dimensional change allows parallel processing of multiple droplets simultaneously, dramatically increasing productivity while maintaining size uniformity through controlled ejection velocity and liquid flow rate.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Productivity

If droplets are ejected with non-zero initial velocity into contact with second liquid, then productivity is improved by rapid production, but manufacturing precision may be worsened due to impact variability

Engineering Contradiction:
Improvespeed of bead formationVSAvoiduniformity of bead size
Core Design Contradiction:
ProductivityVSManufacturing precision

Solution Approach 1:

The invention controls the ejection velocity parameter of droplets and matches it with the flow rate parameter of the second liquid. By optimizing these parameters, droplets impact the liquid stream at controlled points, ensuring consistent bead formation. The non-zero initial velocity enables rapid production while parameter optimization maintains size uniformity.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The apparatus includes monitoring means that detect the region where droplets impact the second liquid. This feedback system allows real-time observation and adjustment of droplet ejection and liquid flow parameters, ensuring that productivity gains from rapid ejection do not compromise bead size uniformity.

Inventive Principle:
Principle #23Feedback

3Productivity

If multiple liquid droplet generators are used to increase productivity, then volume production is improved, but device complexity increases

Engineering Contradiction:
Improvevolume of beads producedVSAvoidnumber of droplet generators and flow channels
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The first liquid serves multiple functions: it acts as a carrier medium for droplet generators, provides a support stream for droplet ejection, and enables synchronized delivery of multiple droplets. This multi-functionality allows multiple droplet generators to operate from a single liquid source, increasing productivity without proportionally increasing system complexity.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The invention merges the carrier liquid function and the impact liquid function into a single second liquid stream. Multiple droplet generators eject into this unified stream, allowing coordinated production from multiple generators while using a single liquid delivery system, thereby increasing productivity without linearly increasing the number of liquid channels required.

Inventive Principle:
Principle #5Merging (Combining)

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 apparatus effectively produces solid beads of uniform size and high yield, with a coefficient of variation of 0.1 or less, facilitating the encapsulation of pharmaceuticals and other materials in a controlled and efficient manner.

Implementation Method 1

The liquid droplet generator may comprise a piezoelectric component

Methodology Applied
Scientific EffectPiezoelectric effect: Piezoelectric Effect

Implementation Method 2

The solvent provided in the liquid droplets dissolves in the second liquid, thereby removing the liquid component of the droplet to leave a substantially solid bead

Methodology Applied
Scientific EffectSolvent extraction: Liquid-Liquid Extraction

Implementation Method 3

The means for generating flow may include a pump

Methodology Applied
Scientific EffectPumping: Pump

Data Source

PatentEP2621623B1Apparatus and method for making solid beads
Publication Date: 2020.12.02 MIDATECH PHARMA (WALES) LTD
  • EP2621623B1 patent drawingFigure 1~2B
  • EP2621623B1 patent drawingFigure 3
  • EP2621623B1 patent drawingFigure 4

AI summary

An apparatus for making solid beads is provided, the apparatus comprising at least one liquid droplet generator operable to generate droplets comprising a solute dissolved in a solvent, and at least one flow channel for carrying a second liquid, at least one liquid droplet generator and at least one flow channel being spaced relative to one another so that, in use, liquid droplets pass through a gas into a second liquid provided in said flow channel, the solvent being soluble in the second liquid so as to cause the solvent to exit the droplets, thus forming solid beads. A method of preparing solid beads is also provided.