Office Chromatography: Miniaturized All-in-One Open-Source System for Planar Chromatography

Area of Science:

• Analytical Chemistry
• Chromatography
• Green Chemistry

Background:

• Current high-performance-thin-layer-chromatography (HP-TLC) systems are offline and automated stepwise.
• Miniaturization and integration of modern printing technologies offer significant advantages for chromatography.
• Office chromatography presents new avenues for accessible analytical techniques.

Purpose of the Study:

• To develop an all-in-one, open-source system for planar and ultrathin-layer chromatography.
• To demonstrate the feasibility of using inkjet printing for sample and mobile phase delivery.
• To create a compact, affordable, and reproducible chromatography instrument.

Main Methods:

• Utilized an InkShield board and thermal inkjet cartridge to print picoliter drops on adsorbent layers at 96 dpi.
• Employed Marlin firmware (commonly used in 3D printing) for precise Cartesian movement of the print head.
• Developed open-source software for complete device control and operation.
• Investigated light-emitting diodes (LEDs) for documentation, including deep UV (254 nm) and RGB LEDs.

Main Results:

• Achieved precise inkjet printing of sample solutions and mobile phases for analyzing dye and paraben mixtures.
• Obtained calibration functions with correlation coefficients exceeding 0.999 via videodensitometry.
• Developed a modular, open-source hardware system that is compact (26 × 31 × 26 cm³), lightweight (<3 kg), and affordable (€810).
• Miniaturized the instrument footprint by a factor of 9 compared to existing instrumentation.

Conclusions:

• The developed system represents a significant miniaturization and cost reduction in chromatography instrumentation.
• The open-source design promotes accessibility, reproducibility, and further innovation in the field.
• The system aligns with green chemistry principles and lean laboratory practices through its reduced material design.