Semi-Automated Sulfuric Acid Test

Job ID: 40396486

Budget: $10 – $30 AUD

Project Title: Microfluidic / Paper-Based Diagnostic Engineer for Sulfuric Acid Delivery System (Methanol Detection Device)

Project Overview

We are developing a paper-based diagnostic strip for methanol detection in alcoholic beverages using the chromotropic acid method. The device uses oxidation chemistry to convert methanol to formaldehyde, followed by a sulfuric acid-assisted chromotropic acid reaction that produces a visible purple color response.

Our current challenge is stabilizing and controlling concentrated sulfuric acid within the paper strip architecture while maintaining strong, reproducible color development and preventing acid migration, evaporation, or inconsistent reagent performance.

We are seeking an experienced engineer (chemical, biomedical, microfluidics, diagnostics, or materials engineering background) to help design an effective acid-retention and controlled-release system for the strip.

Project Goals

We need expert guidance on:

- Controlled retention of concentrated sulfuric acid within a paper-based diagnostic strip
- Designing an in-line acid-release layer compatible with downward capillary flow
- Preventing sulfuric acid flooding, evaporation, hygroscopic instability, and false positives
- Improving color consistency and chromotropic acid reaction intensity
- Material selection for acid-resistant components (PP, PVDF, PTFE, glass fiber, silica matrices, etc.)
- Designing a manufacturable prototype architecture suitable for prototyping and eventual scale-up

Current Concepts Being Explored

We are currently investigating:

- Silica gel coated paper
- PVDF membrane barriers
- Glass fiber acid-retention layers
- 3D printed micro-reservoirs / acid-release cassettes
- Solid-supported sulfuric acid matrices
- Alternative acids to sulfuric acid for improved stability

We would like help determining the best practical design approach.

Deliverables Requested

We are looking for:

- Technical review of our current concept
- Recommended strip architecture (layer-by-layer design)
- Suggestions for controlled sulfuric acid delivery mechanism
- Material recommendations for acid compatibility and manufacturability
- Guidance on whether a 3D printed cassette, spacer system, porous insert, or alternative approach is most suitable
- Optional: basic CAD concept sketch or engineering schematic

Preferred Experience

Strong preference for experience in one or more of the following:

- Lateral flow assays
- Paper microfluidics
- Diagnostic strip development
- Lab-on-paper systems
- Reagent strip engineering
- Microfluidic chemical delivery systems
- Strong acid-compatible material systems
- Membrane and polymer design

Ideal Background

- Chemical Engineering
- Biomedical Engineering
- Materials Engineering
- Diagnostics Product Development
- Microfluidics Engineering

Project Type

Initial consultation + design recommendation

Potential for ongoing collaboration depending on outcomes.

Please include:

- Relevant project examples
- Experience with paper diagnostics or microfluidic systems
- Experience with acid-resistant materials or reagent strip systems
- Estimated consultation availability and approach