Automated sample pretreatment technologies: from surface-based liquid microjunction sampling to flow-based platforms

Area of Science:

• Analytical Chemistry
• Biomedical Engineering
• Process Automation

Background:

• Sample pretreatment is critical for analytical workflows, especially in complex matrices.
• Automation is increasingly adopted to improve efficiency, reproducibility, and sustainability in sample preparation.
• Traditional manual methods are being replaced by integrated and standardized automated strategies.

Purpose of the Study:

• To review two key automation paradigms in sample pretreatment: surface-based liquid microjunction sampling and flow-based automated platforms.
• To analyze the methodological characteristics, design considerations, and limitations of these automation strategies.
• To discuss current trends and future directions in automated analytical workflows.

Main Methods:

• Examination of surface-based liquid microjunction techniques (e.g., LE SA, LM SP, MasSpec Pen) for localized, minimally invasive extraction.
• Analysis of flow-based platforms (e.g., lab-in-syringe, online SPE) emphasizing controlled fluid handling and process integration.
• Review of platform architecture's influence on analytical performance and application scope.

Main Results:

• Liquid microjunction techniques enable in situ analysis of biological and clinical samples but face challenges in spatial resolution and quantitative consistency.
• Flow-based platforms are crucial for high-throughput and trace-level analysis in various fields like biomedicine and environmental monitoring.
• Automation significantly impacts efficiency, reproducibility, and the scope of analytical applications.

Conclusions:

• Automated sample pretreatment, through both liquid microjunction and flow-based systems, offers significant advantages over manual methods.
• Platform design critically influences analytical outcomes, necessitating careful consideration for specific applications.
• Future trends point towards greater integration, intelligent control, and standardization in automated analytical workflows.