Analysing Sources of Error in Total Internal Reflection Microscopy (TIRM) Experiments and Data Analysis

Area of Science:

• Colloid and Surface Science
• Soft Matter Physics
• Nanotechnology

Background:

• Colloidal suspensions exhibit phenomena governed by static and hydrodynamic interactions.
• Precise force measurements are essential for understanding these interactions.
• Total Internal Reflection Microscopy (TIRM) is a key technique for measuring particle-surface interactions.

Purpose of the Study:

• Investigate the impact of noise and parameter choices on TIRM measurements.
• Analyze the influence of error sources on dynamic properties like diffusion coefficients and drift velocities.
• Determine the limitations of TIRM for accurate force and dynamic measurements.

Main Methods:

• Simulated TIRM measurements under various noise conditions.
• Varied particle size and sampling times to assess their effects.
• Focused on analyzing diffusion coefficients and drift velocities.

Main Results:

• Detector shot noise and long sampling times introduce errors in steep potential regions.
• Background noise is negligible below specific thresholds.
• Dynamic data are robust to noise but sensitive to lengthy sampling times and small particle radii.

Conclusions:

• TIRM measurements require careful consideration of noise and parameter selection for accuracy.
• Dynamic results may deviate from theoretical predictions due to partial slip boundary conditions.
• Understanding these limitations is crucial for reliable colloidal suspension characterization.