Nanoscale alumina encapsulation for moisture-resistant effervescent tablets with rapid dissolution

Overview

Effervescent tablets offer a convenient, drinkable medication format, but their hygroscopic ingredients require plastic packaging to prevent moisture degradation. This solution applies Atomic Layer Deposition (ALD) to create ultra-thin alumina (Al2O3) moisture barrier coatings, typically 5-50 nm thick, on effervescent tablets or their powder formulations. The technology delivers exceptional moisture resistance while preserving the rapid dissolution that makes effervescent products appealing. By enabling effective moisture protection without plastic packaging, this approach supports sustainability initiatives and may enable transition to paper-based packaging.

Technical specifications

Key features:

• Ultra-thin ALD alumina films (5-50 nm) provide moisture barriers without significantly increasing tablet weight or volume
• Exceptional conformality on complex 3D surfaces and tablet powder particles
• Gentle low-temperature deposition at 45-65°C, suitable for heat-sensitive active pharmaceutical ingredients (APIs)
• Versatile application: can encapsulate the entire powder formulation, the hygroscopic citric acid component alone, or infiltrate nanopores in pressed tablets
• Alumina (Al2O3) is FDA-approved as a safe drug and food additive
• Scalable batch processing compatible with both tablet and powder formats
• Potential for controlled drug release engineering beyond moisture protection

Technology readiness level

This technology is at an early-to-mid stage of development specific to effervescent tablet applications. Prior research from AstraZeneca and the University of Helsinki has demonstrated ALD's effectiveness for moisture barriers and dissolution control in pharmaceutical particles, including safety validation in human lung cell cultures. The proposed 6-month feasibility study will use a benchtop ALD reactor suitable for heat-sensitive materials to optimize film thickness. Validation will include accelerated stability testing at 40°C and 75% relative humidity, benchmarking mass uptake against untreated tablets, and dissolution testing to confirm rapid CO2-driven disintegration. A scale-up pathway will be developed to enable transition to commercial production and paper-based packaging.