Rethinking gamete/embryo isolation and culture with microfluidics

Abstract

IVF remains one of the most exciting modern scientific developments and continues to have a tremendous impact on people's lives. Since its beginnings, scientists have studied and critically analysed the techniques in order to find ways to improve outcomes; however, little has changed with the actual technology and equipment of IVF. Semen is still processed in test tubes and fertilization and culture still occurs in culture dishes. New technological possibilities exist with the burgeoning advancement of microfluidic technology. Microfluidics is based on the behaviour of liquids in a microenvironment. Although a young field, many developments have occurred which demonstrate the potential of this technology for IVF. In this review, we briefly discuss the physical principles of microfluidics and highlight some previous utilizations of this technology, ranging from chemical analysis to cell sorting. We then present the designs and outcomes for microfluidic devices utilized thus far for each step in IVF: gamete isolation and processing, fertilization, and embryo culture. Finally, we discuss and speculate on the ultimate goal of this technology--development of a single, integrated unit for in-vitro assisted reproduction techniques.

Assessment of sperm chemokinesis with exposure to jelly coats of sea urchin eggs and resact: a microfluidic experiment and numerical study

“…The solid resact (500·g as received; Phoenix Pharmaceuticals Inc., Balmont, CA, USA) was first dissolved to 500·l of final volume for the storage concentration of 1·g·l -1 (8.035ϫ10 human sperm sorters (Cho et al, 2003;Suh et al, 2003). An SU-8 (negative, near UV, epoxy) photoresist master mold with a rectangular channel was constructed on a silicon wafer via photolithography.…”

Improvement of Fertilization Rates of In Vitro Cultured Human Embryos by Exposure to Sound Vibrations

“…Two different in vitro culture systems have been developed to mimic the natural environment effect: (i) movement applied directly to the culture media and (ii) dynamization of the embryo microculture [5]. Several groups have tried to apply a variety of methods, such as mechanical microvibrations to embryo culture plates [6][7][8], the use of dynamic fluids in embryo culture [9][10][11][12][13][14][15][16] or the use of a tilting embryo culture system [17]. An improvement in the quality of in vitro human blastocysts was noted when the tilting embryo culture system was used [18,19] and also when dynamic microfunnel culture conditions were applied [12]; in the latter study a higher rate of embryo implantation and subsequent pregnancy was also noted.…”

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

“…Specifically, the area of reproductive medicine is prone to improvements that involve miniaturized systems, such as microfluidic sperm sorters (Cho et al, 2003;Suh et al, 2003). For this vision to occur, it is critical that these instruments not only function as designed, but also be easy to attain, simple to operate, and available on a need to use basis (Cho et al, 2003;Ng et al, 2002;Belder and Ludwig, 2003).…”

“…For this vision to occur, it is critical that these instruments not only function as designed, but also be easy to attain, simple to operate, and available on a need to use basis (Cho et al, 2003;Ng et al, 2002;Belder and Ludwig, 2003). Precursors to these tools are currently in development and may include autonomous polydimethylsiloxane (PDMS) made microfluidic systems that have already demonstrated to greatly improve our biological analysis capabilities (Sia and Whitesides, 2003;Suh et al, 2003;Hu et al, 2002). PDMS offers many advantages, such as being inexpensive, harmless to cells, transparent, easy to fabricate, and having the capability to bond other surfaces to form watertight seals (Sia and Whitesides, 2003;Ng et al, 2002;Hu et al, 2002;Olah et al, 2005;Berdichevsky et al, 2004).…”

“…1) was used as the test platform (Cho et al, 2003;Suh et al, 2003). This device is an enclosed PDMS based microfluidic system and has been shown to enable isolation of motile sperm from semen samples for use in infertility analysis and treatments (Cho et al, 2003;Suh et al, 2003).…”