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Open pulled straw vitrification
Introduced by Gábor Vajta in 1998, OPS is an open system at cooling and warming, and safely closed system at storage to prevent cross contamination in liquid nitrogen. OPS is the first purpose-designed tool for high-speed vitrification. It is also widely acknowledged as one of the best ones, with both cooling and warming rates around 20,000 C⁰/min (Vajta et al., 1998). It can be used for MII phase oocyte and any stages of embryo development successfully. One straw set contains one pulled straw and a container, available in 5 different colors.
The FIRST human baby after oocyte vitrification (Kuleshova et al., 1999)
The FIRST cloned animal after embryo cryopreservation (Tecirlioglu et al., 2003)
The FIRST calf after cryopreservation of immature oocytes (Vieira et al., 2002)
The HIGHEST survival-developmental rates after cryopreservation of human ES cells (Reubinoff et al., 2001)

Loading, cooling, and package

Touch the droplet with the narrow end of the straw and the capillary effect will force the medium to enter it. Put the straw into liquid nitrogen for vitrification immediately, and then transfer the straw into the pre-cooled container.

Warming and expelling

Tightly cover the wide end of the straw with your index fingers. The medium will flow out from the straw as a result of the increased pressure of warming air inside the straw.

*VitaVitro Straw Set is approved for marketing in China, Europe and USA.

Please contact us to get more information.

VitaVitro Vitrification Kit, VitaVitro Warming Kit
Instruction video
How to vitrify all stages
This movie demonstrates how to vitrify oocytes and embryos using VitaVitro Cryopreservation System
Mobile App
Welcome to free download the first APP for vitrification. A mobile app that is not a manual, not a video, not a guide, but A COACH providing:

step-by-step on-time instructions during the whole vitrification-warming process with a built-in stopwatch function

interactive personalized information with options to choose the appropriate route

ample possibility to obtain background information opinions and suggestions

direct contact to the inventor and producer

  Android OS
Outcomes after cryopreservation
Data obtained by an independent clinic in the United States of America
Data from independent Chinese clinics (ongoing observations)

1. Vajta G., Holm P., Kumayama M., Booth P.J., Jacobsen H., Greve T., Callesen H. Open Pulled Straw (OPS) Vitrification: A New Way to Reduce Cryoinjuries of Bovine Ova and Embryos. Molecular Reproduction and Development. 1999; 51(1): 53-58. DOI: 10.1002/(sici)1098-2795(199809)51:1<53::aid-mrd6>;2-v.

2. Kuleshova, L., Gianaroli, L., Magli, C., Ferraretti, A., Trounson, A. Birth following vitrification of a small number of human oocytes: Case Report. Human Reproduction. 1999; 14(12): 3077–3079. DOI:10.1093/humrep/14.12.3077.

3. Vieira, A., Mezzalira, A., Barbieri, D., Lehmkuhl, R., Rubin, M. I., Vajta, G. Calves born after open pulled straw vitrification of immature bovine oocytes. Cryobiology. 2002; 45(1): 91–94. DOI: 10.1016/s0011-2240(02)00109-8.

4. Reubinoff, B. E., Pera, M. F., Vajta, G., Trounson, A. O. Effective cryopreservation of human embryonic stem cells by the open pulled straw vitrification method. Human Reproduction. 2001; 16(10): 2187–2194. DOI:10.1093/humrep/16.10.2187.

5. Vajta G. Are programmable freezers still needed in the embryo laboratory? Review on vitrification. Reproductive Bio-Medicine Online. 2006; 12: 779-796. DOI: 10.1016/s1472-6483(10)61091-7.

6. Vajta G. Vitrification in human and domestic animal embryology: work in progress. Reproduction, Fertility and Development. 2012; 25(5): 719-727. DOI: 10.1071/RD12118.

7. Vajta G., Reichart A., Baldi F. U., Rienzi L. From a back up technology to a strategy-outlining approach: the success story of cryopreservation. Expert Rev. Obstet. Gynecol. 2013; 8(2): 181-190. DOI: 10.1586/eog.12.80.

8. Munck N. D, Vajta G. Safety and efficiency of oocyte vitrification, Cryobiology. 2017; 78: 119-127. DOI: 10.1016/j.cryobi-ol.2017.07.009.

9. Vajta G. Vitrification in ART: past, present and future. Theriogenology. 2020; 150: 276-279. DOI:1016/j.theriogenolo-gy.2020.01.057.

 Ordering information
VitaVitro Straw SetV001001Red x1、Green x1、Blue x1、Black x1、White x1
VitaVitro Vitrification Kit
HHM  1.0mL x1 HV1  1.0mL x1 HV2  1.0mL x1
HHM  4.5mL x1HV1  4.5mL x1 HV2  4.5mL x2
HHM  2.0mL x1HV1  2.0mL x2 HV2  2.0mL x2
VitaVitro Warming Kit
HHM  1.8mL x1 HW1  1.5mL x2HW2  1.0mL x1
HHM  4.5mL x2HW1  4.5mL x1HW2  4.5mL x1
HHM  2.0mL x3HW1  2.0mL x5HW2  2.0mL x2
Teeth Forceps
Heat sealer
Container cutter
 Material safety data sheet
VitaVitro Straw Set Safety Data Sheet
VitaVitro Vitrification Kit Safety Data Sheet
VitaVitro Warming Kit Safety Data Sheet
 User guide
User guide
 Quality control
VitaVitro Straw Set

Endotoxin < 0.5EU/device

Mouse embryo assay ≥ 80%

Sterility test

VitaVitro Vitrification Kit, VitaVitro Warming Kit

pH 7.2-7.6

Endotoxin < 0.25 EU/mL

Mouse embryo assay ≥ 80%

Sterility test

Heat sealer
Container cutter
Teeth Forceps