Label-Free Microfluidic Impedance Cytometry for Acrosome Integrity Assessment of Boar Spermatozoa

Area of Science:

• Biomedical Engineering
• Veterinary Science
• Reproductive Biology

Background:

• Microfluidics and lab-on-chip technologies offer rapid, low-cost alternatives for complex biomedical analyses.
• Standardized, label-free semen analysis methods are needed in veterinary and human fertility applications.
• Acrosome integrity is a critical parameter for evaluating sperm quality and fertility potential.

Purpose of the Study:

• To develop and validate a microfluidic impedance cytometry tool for assessing sperm acrosome integrity.
• To establish a label-free method for determining acrosome reaction status in spermatozoa.
• To evaluate the potential of microfluidic impedance cytometry for semen analysis in fertility contexts.

Main Methods:

• Spermatozoa were analyzed using microfluidic impedance cytometry after inducing acrosome reaction with calcium ionophore A23187.
• Electrical properties (magnitude, phase, opacity) of individual spermatozoa were measured.
• Results were compared against conventional staining methods for acrosome integrity assessment.

Main Results:

• Opacity at 19 MHz over 0.5 MHz correlated significantly with acrosome integrity.
• A cut-off threshold of 0.86 for opacity demonstrated high diagnostic performance (98% sensitivity, 97% specificity).
• Microfluidic impedance cytometry effectively distinguished between treated and non-treated spermatozoa.

Conclusions:

• Microfluidic impedance cytometry provides a highly accurate and efficient method for determining sperm acrosome integrity.
• The developed tool shows potential as a versatile alternative for semen analysis in veterinary and human fertility clinics.
• Label-free impedance measurements offer a standardized approach for fertility assessments.