Are CellSeal Vials compatible with cryopreservation in liquid nitrogen?

CellSeal Vials are validated in actual conditions. CellSeal Vials were subjected to freezing, storage in liquid nitrogen, a drop test, frozen transportation, and thawing. Following thawing, a series of container integrity tests were performed, including dye and bacterial immersion studies. All vials met the defined criteria for each test.

Completed Studies

Has an extractable/leachable study been completed on CellSeal Vials?

CellSeal Vials have demonstrated low levels of extractables during a leachables study.*

*E&L data is available


Is a Certificate of Compliance provided with the CellSeal Vial?

Yes. A Certificate of Compliance per lot number is provided to the customer with each purchase.

Are the component materials suitable for use with biological products?

All specimen contacting materials are manufactured from USP Class VI compliant materials, and have been subjected to biological safety testing that included genotoxicity, cytotoxicity, sensitization, irritation, hemocompatibility, and acute systemic toxicity.


What is the expiration date of the CellSeal Vial?

The CellSeal Vial has an expiration date of three years from date of manufacture.

Instructions For Use

What is the volume that can be frozen in CellSeal Vials?

The expansion profile of different solutions are dependent on content, concentration and freezing process. We suggest evaluating the expansion profile of your product in CellSeal Vials under the intended conditions of use. Please contact us for additional information.

How do I use the CellSeal Vial?

Please refer to the corresponding recommended instructions for guidance (IFU) below on how to use the CellSeal Vial.

CellSeal needle user guide (PDF)

CellSeal needleless user guide (PDF)


nLiven PR

Is nLiven PR currently used in any clinical trials?

Yes. nLiven PR is used in multiple clinical studies across the globe.

What is the shelf life for nLiven PR?

Sexton has data supporting performance up to at least 29 months from date of manufacture at -20C storage

Is there viral clearance testing for the inactivation step?

Yes, viral inactivation studies have been completed.

How are pathogens reduced in nLiven PR?

nLiven PR is pathogen reduced by electron-beam irradiation.

How is nLiven PR different than Stemulate?

nLiven PR contains a pathogen-reduction step in the manufacturing process to minimize the residual risk of pathogens/viruses contained in the final product.

Platelet Lysate

Do you have a consistent supply of platelets?

Sexton has supply agreements in place.

Do I have to include heparin in Sexton platelet lysates? Is heparin already present in the bottle?

Heparin is not present in the bottle; nor is it used throughout the manufacturing process. Stemulate, nLiven PR and T-Liven PR are processed to deplete the amount of fibrinogen and therefore minimize the possibility of further clotting. Heparin should not be required for use.

If I see clots in the thawed product, is that normal? How should it be handled?

Post-thaw, there is possible aggregate formation due to further conversion of fibrin to fibrinogen. Further filtration is not recommended. (might reduce the number of growth factors in the medium) However, filtration may be done and would require validation by the end user.

What are freeze/thaw recommendations of the product?

If not using the entire volume, upon initial thaw, aliquot into desired volumes and refreeze at -20C. Internal data indicates multiple freeze/thaw cycles do not harm product performance. However, this practice should be qualified for your manufacturing protocol. Sexton recommends limiting your freeze/thaw to an absolute minimum. Additional particulate could be visible following thaw.

How should you handle platelet lysate after opening?

If you do not use the complete amount at once, you should aliquot the volumes needed and then freeze. Limit the freeze thaw cycle to one. (thawing 2 times)  Post thaw, recommend keeping in fridge for approx. 2-3 weeks in complete media. You may keep aliquots in the freezer until the expiry date. 

Do you offer a Certificate of Analysis for all hPL products?

All Stemulate products, Research and Clinical grade are supplied with a CoA upon purchase 
Research grade Stemulate CoA provides sterility information; Endotoxin, Mycoplasma, and Sterility  

Clinical or GMP compliant Stemulate provides all release criteria, data, and information 

All Pathogen Reduced products, nLiven PR and T-Liven PR, are supplied with a CoA that provides all release criteria, data, and information


How do you address viral, TSE and microbiological safety of platelet lysate? Are the donors screened prior to use?

Our platelet lysates are manufactured using expired apheresis platelet units sourced from AABB-accredited and FDA-registered blood centers. Donors provide the units voluntarily and are not reimbursed for their units.  The platelet units are qualified according to FDA and AABB requirements for platelets for transfusion, including appropriate donor screening and testing for relevant communicable diseases according to 21 CFR 606, 21 CFR 610, 21 CFR 640, and relevant guidance. Cook Regentec maintains records supporting this documentation.  TSE Statements, Certificate of Compliance, and animal derived statements are available for Stemulate. 

Do you have a Quality Management System certification?

Yes. We are ISO9001:2015 certified.

What is the intended use for platelet lysate?

Ex vivo expansion of cells such as MSCs, ASCs, T Cells, etc. Please connect with us to learn which Sexton hPL is right for your application.


Is Stemulate currently used in any clinical trials?

Yes. Stemulate is used in multiple clinical studies across the globe.

What is the expiration date of Stemulate?

29 months from the date of manufacture at -20C storage.

Do you evaluate the performance of each lot of Stemulate?

Clinical-grade Stemulate undergoes performance testing in cell culture as part of the release criteria to qualify each lot. The product must perform standard cell expansion following our growth verification assay. Growth factor data is not collected per lot nor is it a determinant of lot release.

What are the typical concentrations for different cell types? Do you have references for these?

Data demonstrate that Stemulate is generally suitable at an equivalent concentration of FBS or AB Serum depending on the cell type. Studies have been published that indicate a reduction of HPL concentration is possible and has been reported as effective down to 0.5%.

What is the difference between research and clinical grade Stemulate?

Both grades are manufactured under the same environmental conditions and following the same protocols. The Clinical grade material is subjected to more robust release testing and batch record documentation as indicated by the information provided on the certificate of analysis.

T-Liven PR

What is the shelf life for T-Liven PR?

Sexton has data supporting performance up to at least 17 months from date of manufacture at -20C storage

How is T-Liven PR different from Stemulate and nLiven PR?

T-Liven PR is verified to support T cell growth. Each lot is released using a T cell growth verification assay. It’s packed in bags for compatibility in common manufacturing systems. Like nLiven PR, T-Liven PR has undergone the additional step of pathogen-reduction.