MRT letter: Micro- to nanoscale sample collection for high throughput microscopy.

Area of Science:

• Microscopy and imaging techniques
• Fluid dynamics in microscale systems
• Biotechnology and biophysics

Background:

• High-throughput microscopy often requires spatially fixed and densely populated samples.
• Low sample density necessitates extensive searching, hindering efficient analysis.
• Collecting objects in a hydrated state at a single location is a significant challenge.

Discussion:

• A novel method utilizes a circular coverslip to generate a squeezing flow, effectively collecting diverse microscopic objects.
• This technique concentrates particulate (microbeads, nanobeads, algal cells) and non-particulate (EGFP) matter at the coverslip rim.
• Optimal sample volumes (2–4 µL) and compression speeds (100–1000 µm/s) were determined for efficient collection.

Key Insights:

• The coverslip squeezing flow method successfully relocates objects to the rim region with high efficiency.
• Simple manual placement of the coverslip yields comparable results to motorized systems.
• This technique is robust across various sample types, including live cells and nanoparticles.

Outlook:

• Potential applications in sample preparation for low-density biological and material science investigations.
• Further research could explore optimizing coverslip geometry and compression dynamics.
• This method offers a simplified and cost-effective approach to sample concentration for advanced imaging.