Sil-Select STOCK™

Sperm preparation media - stock solution

Sil-Select Stock™ is our home made stock solution for preparing density gradient system for semen preparation. Sil-Select Stock™ is an isotonic solution of silane-coated silica particles in a chemically defined, balanced salts solution with HEPES (pH buffer). Sil-Select Stock can be used in combination with IUI, IVF and ICSI. The density of Sil-Select Stock™ is approximately 1.12g/ml.
Extensive testing during the design of the product has shown it to be non-cytotoxic and non-irritant with a non-significant allergenic potential.
Sil-Select Stock™ is manufactured from raw colloidal silica, so we have full control over each step in the production process. We have developed a very accurate purification system which results in a very clean product with endotoxin levels below 0.5EU/ml.

Sil-Select Stock™ complies with the following specifications:

pH 7.2 - 7.9 (7.2-7.6 at release)
Osmolality 300-330mOsm/kg
Sterility Sterile
Endotoxine < 0.5 EU/mL
Sperm Survival test ≥ 80% motility recovery after 4 hours exposure ≥ 75% motility recovery after 24 hours exposure
Density 1.115-1.125g/ml
Viscosity in cP (25°C) <1.75cP
Shelflife 18 months from date of produce
Albumin FDA (USA) and EMEA (Europe) compliant


Europe: CE-marked - USA: US FDA cleared
Canada: Health Canada License - Brazil: registered

Product order codes

SIS100 Sil-Select Stock - 100mL
SIS500 Sil-Select Stock - 500mL
SIS100G Sil-Select Stock with gentamicin - 100mL

The product composition can be found in the MSDS (see Resources). Additional information on some components is provided below:

Component Benefit
HEPES (18 mM)

HEPES stabilizes the pH under air (Clark and Swain 2014), therefore CO2 incubation is not required.

Earle’s Balanced Salt Solution (EBSS)

The composition of the salt solution results in an optimum pH and osmolality environment for sperm cells.

Silane coated colloidal silica

Density gradient media have been optimized for maximum efficiency in the selection of spermatozoa for use in ART. Their density is directly linked with their functionality and depends on the % silanized colloidal silica particles added in the media.

Product literature

     Dal Canto, MB.; Mignini Renzini, M.; Brambillasca, F.; Cepparo, H.; Comi, R.; Villa, A.; Rangoni, G.; Mastrolilli, M.; Crippa, M.; de Ponti, E.; Nielsen, HI.; Fadini, R. , IVM--the first choice for IVF in Italy., Reprod. Biomed. Online (2003),Vol.13,No.2,pp.159-65
     Ha, JH.; Oum, KB.; Chung, HM.; Chung, MK.; Kim, HK.; Ko, JJ.; Yoon, TK.; Cha, Ky.;, Comparison of Sperm Motility, Recovery Rate, and Fertilization Rate using Three Different Sperm Preparation Methods: Swim-up, Percoll, Sil-Select., Korean J Fertil. Steril. (26),Vol.2,pp.257-263
     Jarupoonpol, S. Choktanasiri, W.; Wongkurlarb, A.; Rattanasiri, S.; Sukprasert, M., Sperm Motility and DNA integrity affected by different g-forces in the preparation of sperm in uterine specimens., Andrologia (46),Vol.4,pp.391-398
     Jedrzejczak P., Rzepczynska I., Taszarek-Hauke G., Pawelczyk L., Effect of sperm subpopulation's kinetics on human fertilization in vitro, Archives of Andrology (2005),Vol.51,pp.185-193
     Trokoudes, KM.; Minbattiwalla, MB.; Kalogirou, L.; Pantelides, K.; Mitsingas, P.; Sokratous, A.; Chrysanthou, A.; Fasouliotis, SJ.;, Controlled natural cycle IVF with antagonist use and blastocyst transfer., Reprod. Biomed. Online (2005),Vol.11,No.6,pp.685-9

Literature concerning the components

     Clark, N.A. and Swain, J.E., Buffering systems in IVF., Culture media, Solutions, and Systems in Human ART, by P. Quinn (2014),pp.30-46


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