Functionalization of Mesoporous Silica Nanoparticles with a Cell-Penetrating Peptide to Target Mammalian Sperm in vitro

Abstract

Aim: This study aimed to investigate the effects of actively targeting mesoporous silica nanoparticles (MSNPs) toward mammalian sperm with a cell-penetrating peptide (C105Y), with subsequent analysis of binding rates and nano-safety profiles. Materials & methods: Boar sperm were exposed in vitro to C105Y-functionalized MSNPs or free C105Y, in a series of increasing doses for up to 2 h, followed by the evaluation of sperm motility, kinematic parameters, acrosome morphology, MSNP-sperm binding and cell fluorescence levels. Results: C105Y-functionalized MSNPs preserved their biocompatibility with sperm, and exhibited an approximately fourfold increase in affinity toward gametes, compared with unmodified MSNPs, during the early stages of incubation. Conclusion: Our findings support the application of MSNPs and active targeting to sperm as valuable tools for reproductive biology.

Keywords::

• cell-penetrating peptides
• delivery
• functionalization
• mesoporous silica
• nanoparticles
• sperm

Acknowledgements

The authors wish to acknowledge R Morrisson, C Huang and M Yeste for their support, and C Gardiner for his help in characterizing the nanoparticles.

Financial & competing interests disclosure

The authors have a patent pending related to the work discussed in this article entitled ‘Delivery Method’ (PCT Patent Application Number PCT/GB13/053394 filed on the 20th December 2013). N Barkalina is funded by the Clarendon, Scatcherd European and Cyril & Phillis Long Schemes. The project is also funded by the Nuffield Department of Obstetrics and Gynaecology, and an EPSRC Pathways to Impact Award (University of Oxford). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Additional information

Funding

The authors have a patent pending related to the work discussed in this article entitled ‘Delivery Method’ (PCT Patent Application Number PCT/GB13/053394 filed on the 20th December 2013). N Barkalina is funded by the Clarendon, Scatcherd European and Cyril & Phillis Long Schemes. The project is also funded by the Nuffield Department of Obstetrics and Gynaecology, and an EPSRC Pathways to Impact Award (University of Oxford). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed. No writing assistance was utilized in the production of this manuscript.