A simple zeta method for sperm selection based on membrane charge

Abstract

Objective: The objectives were: [1] to develop a simple zeta potential method for sperm isolation; and [2] to analyze the sperm maturity, morphology, kinematic, and DNA parameters.

Design: The phenomenon of sticky sperm adhering to slide surfaces was adapted for collecting charged sperm.

Setting: Clinical and academic research environment.

Patient(s): Discarded colloid-washed sperm from routine laboratory testing (n = 8).

Intervention(s): Sperm were centrifuged in serum-free medium and collected for analyses.

Main outcome measure(s): Kinematic parameters, DNA integrity, and maturity.

Result(s): The percentages of mature (73.0% +/- 0.5% vs. control 63.5% +/- 0.5% SEM) and DNA intact sperm (85.0% +/- 0.3% vs. 69.5% +/- 0.5%) increased in the male factor subgroup. Strict normal morphology (19.3% +/- 0.1% vs. 10.0% +/- 0.1%), hyperactivation (7.0% +/- 0.1% vs. 3.6% +/- 0.1%), and progressive motility (29.1% +/- 0.1% vs. 19.9% +/- 0.1%) increased by twofold.

Conclusion(s): The zeta method improved sperm parameters associated with increased fertilization and pregnancy after assisted reproduction procedures. Manipulation from the attaching-detaching process stimulated sperm metabolism without causing premature acrosome reactions. Total motility was unchanged suggesting a lack of association between total motility and zeta potential.