Evaluation of three substitutes for Percoll in sperm isolation by density gradient centrifugation

Area of Science:

• Reproductive Biology
• Biotechnology
• Materials Science

Background:

• Sperm preparation is crucial for assisted reproductive technologies (ART).
• Gradient centrifugation using density media is a common sperm isolation method.
• Different coating materials on silica particles are used for sperm separation.

Purpose of the Study:

• To compare the efficacy of silane-coated silica particles (ISolate, PureSperm) and iodixanol (OptiPrep) against polyvinylpyrrolidone (PVP)-coated silica particles (Percoll) for sperm recovery.
• To evaluate the impact of these media on sperm recovery rates, vitality, motility, morphology, and chromatin condensation.

Main Methods:

• Gradient centrifugation was employed for sperm isolation.
• Four density media were tested: PVP-coated silica (Percoll), silane-coated silica (ISolate, PureSperm), and iodixanol (OptiPrep).
• Efficacy was assessed by measuring sperm recovery percentage, vitality, progressive motility, normal morphology, and normal chromatin condensation.

Main Results:

• No significant difference in sperm recovery was observed between PVP-coated and silane-coated silica particles for men with normal sperm counts or oligozoospermia.
• Iodixanol (OptiPrep) resulted in significantly lower sperm recovery compared to both PVP-coated and silane-coated silica particles.
• Sperm vitality, progressive motility, normal morphology, and normal chromatin condensation remained unaffected across all tested sperm isolation products.

Conclusions:

• Silane-coated silica particles offer comparable sperm recovery to PVP-coated silica particles for assisted reproduction.
• Iodixanol is less effective for sperm recovery in gradient centrifugation compared to silica-based media.
• All tested media effectively preserve sperm quality parameters crucial for ART success.