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A surface-modified sperm sorting device with long-term stability.

Jason M Wu·Yaokuang Chung·Kimberly J Belford·Gary D Smith·Shuichi Takayama·Joerg Lahann
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Abstract

Microfluidic devices fabricated from poly (dime- thylsiloxane) (PDMS) offer the ability to improve our biological and medical capabilities. Although PDMS offers a range of intriguing benefits for biomedical applications, the intrinsically hydrophobic nature of PDMS may impede with the tremendous potential of these devices. Here, we describe a PDMS-based sperm sorting device, which has been surface-modified via graft-co-polymerization of poly(ethylene glycol) methyl ether methacrylate to create a moderately hydrophilic and non-fouling surface. This process involves the exposure of PDMS to UV/ozone, which activates the PDMS surface to bond to the substrate and, at the same time, initiates the graft-co-polymerization from the PDMS surface. In this study, we confirmed long-term stability of surface-modified PDMS for up to 56 days based on Fourier transformation infrared spectroscopy (FTIR), contact angle measurements, and protein adsorption studies. Moreover, the applicability of our method to PDMS-based sperm sorting devices was demonstrated by successfully sorting human sperm.

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Cell Culture TechniquesCell SeparationCells, CulturedEquipment DesignEquipment Failure AnalysisFlow CytometryHumansMaleMicrofluidic Analytical TechniquesSpecimen HandlingSperm CountSpermatozoaSurface PropertiesEvaluation StudyJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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Jason M Wu, Yaokuang Chung, Kimberly J Belford, Gary D Smith, Shuichi Takayama, Joerg Lahann. 2006. A surface-modified sperm sorting device with long-term stability.. https://doi.org/10.1007/s10544-006-7705-7

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