Sonic Low Pressure Spray Drying for Bioactive Powders
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional spray drying methods face challenges in stabilizing thermally labile biologicals due to excessive shear stress, large droplet sizes, and high pressure requirements, which lead to bioactivity loss and inefficient drying processes, especially when handling thick pharmaceutical and vaccine formulations.
Innovation Solution
The method involves using a high frequency sonic or ultrasonic nozzle with low pressure gas to create small, uniform droplets of bioactive materials, which are then dried into powders with minimal thermal and mechanical stress, utilizing a combination of specific formulations and a spray drying process that includes vibrating nozzles at frequencies ranging from 1 kHz to 100 kHz to achieve stable, small droplet sizes and high processing throughput.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If conventional spray drying methods are used to stabilize thermally labile biologicals, then high volume product throughput can be achieved, but excessive shear stress and high pressure cause loss of bioactivity
Solution Approach 1:
The patent employs ultrasonic vibration at frequencies of 20-200 kHz to atomize the liquid stream into fine droplets. This mechanical vibration replaces conventional high-pressure mechanical atomization, reducing shear stress and pressure exposure on thermally labile biologicals while maintaining efficient droplet formation for spray drying throughput
Solution Approach 2:
The invention substitutes mechanical pressure-based atomization systems with ultrasonic vibration-based atomization. This replacement eliminates the need for high-pressure pumps and mechanical atomizing nozzles that generate excessive shear stress, while achieving comparable or superior atomization efficiency for high-volume processing
2Ease of manufacture
If high pressure is applied to atomize thick pharmaceutical formulations, then atomization can be achieved, but droplet size distribution becomes overly broad and bioactivity is lost
Solution Approach 1:
Ultrasonic vibration at 20-200 kHz provides consistent, high-frequency oscillations that atomize thick formulations into uniform fine droplets without the pressure-induced broad size distribution. The vibration frequency can be optimized to match the formulation's viscosity and density characteristics
Solution Approach 2:
The patent changes the atomization mechanism from pressure-driven to vibration-driven, and further optimizes droplet size by adjusting vibration frequency (20-200 kHz range). This parameter control enables precise droplet size distribution even for formulations with high viscosity and density
3Manufacturing precision
If higher frequency ultrasonic vibrations are used to reduce droplet size, then smaller droplets are formed, but processing capacity decreases
Solution Approach 1:
The patent employs a dynamically adjustable ultrasonic vibration system that can operate across a wide frequency range (20-200 kHz). This allows real-time optimization of vibration frequency based on formulation properties and desired droplet size, maintaining processing capacity while achieving fine atomization for thick formulations
Solution Approach 2:
By enabling frequency adjustment across 20-200 kHz, the system can optimize the balance between droplet size and processing capacity. Higher frequencies produce smaller droplets when needed, while lower frequencies maintain higher throughput, providing flexible control over the trade-off between precision and productivity
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
This approach results in stable, bioactive powders with smaller droplet sizes, reduced thermal stress, and enhanced storage stability, allowing for the preservation of sensitive materials like proteins, viruses, and bacteria with minimal loss of bioactivity, even in harsh organic solvents and high temperatures.
Implementation Method 1
The ultrasonic vibrations are focused at the tip where, as the liquid flows through, the oscillating tip disintegrates the liquid into micro-droplets
Implementation Method 2
conventional ultrasonic nozzles use a piezoelectric transducer to convert electrical energy to mechanical vibrations at ultrasonic frequency range
Implementation Method 3
conventional ultrasonic nozzles use a piezoelectric transducer to convert electrical energy to mechanical vibrations at ultrasonic frequency range
Implementation Method 4
drying the droplets in a stream of drying gas to form powder particles of the bioactive material
Data Source
AI summary
This invention provides methods of spray drying pharmaceutical powders from a vibrating nozzle at low pressures. The method can effectively spray dry thick or viscous solutions or suspensions to provide small uniform particles. The invention includes dry particle compositions prepared by methods of low pressure spraying from vibrating nozzles.