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Thawing Frozen Cells: A Checklist for the Bench

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Thawing reverses the logic of freezing: cells are cooled slowly but warmed quickly. This checklist follows published guidance from the ATCC and ECACC culture collections. Your own validated method and the data sheet for the cell line come first. Before the vial comes out Put on cryogenic gloves and a face shield. A vial that has drawn in liquid nitrogen can burst as it warms. Pre-warm the culture medium. Know the rack, box and position of the vial, so the box is out of the vessel for as short a time as possible. Every other vial in the box warms while you search. Thawing Warm the vial quickly in a 37 °C water bath with gentle agitation, for about two minutes. Keep the cap and seal out of the water. Wipe the vial with 70% ethanol before opening. After thawing Transfer the contents to pre-warmed medium. For sensitive lines, add medium in small steps to avoid osmotic shock. Change the medium 8 to 24 hours later to remove the cryoprotectant. Record the vial as used and update the count for...
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Stem Cell Cryopreservation in Numbers: A Quick Reference for Processing Laboratories

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The cryopreservation of stem cells runs on a small set of numbers. This page collects the ones that shape equipment decisions, drawn from the EBMT Handbook and from the data sheet for the Cryolab CryoBank tank range. Your own validated protocol and your regulator always take precedence. Before freezing Hold time: up to 72 hours at 2 °C to 6 °C is accepted, but freezing within 48 hours is recommended. Cell concentration: usually no more than 4 x 10 8 nucleated cells per ml, or 2 x 10 8 if the product has waited more than 24 hours. The freeze Cryoprotectant: DMSO at a final concentration of 5% to 10%. Cooling rate: 1 °C to 2 °C per minute in a controlled-rate freezer. Record: the temperature curve for each run, kept with the unit's storage record. Storage Temperature: vapour phase nitrogen at -140 °C or below. Many programmes work to -150 °C for clinical material. Where to measure: the top storage position, lid open, just before a fill. Duration: studies have found cryostored CD34 ...
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Frozen Red Cell Storage: A Checklist for Blood Bank Managers

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Frozen red cells are the long-term reserve of a blood service: rare groups, units for patients with multiple antibodies and contingency stock. UK guidance allows them to be stored for up to 30 years, provided the storage temperature is guaranteed. This checklist turns that condition into things you can inspect. Method and temperature Confirm which glycerol method your process is validated for. High glycerol units: -60 °C to -80 °C in an electrical freezer. Low glycerol units: -140 °C to -150 °C in vapour phase liquid nitrogen. Check the alarm set points match the validated band, not a round number. The vessel Map the temperature at the top storage position at the working liquid level. Use automatic filling so the level does not drift between top ups. Confirm level and temperature are logged continuously. Track liquid nitrogen consumption. A rising trend can be the first sign of a failing vacuum. Keep spare capacity so a vessel can be emptied without warming its contents. Records Keep a...
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Cryogenic PPE by Task: A Practical Checklist for Liquid Nitrogen Work

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A task by task checklist for laboratory managers reviewing liquid nitrogen PPE. Retrieving canes from a vapour phase store Elbow or mid-arm waterproof gloves, safety glasses or a face shield depending on the store design. Routine top-ups from a supply vessel Shoulder or elbow-length gloves, face shield with chin guard, waterproof apron. Decanting into an open dewar Shoulder-length gloves, face shield, apron long enough to reach the shoes. Short bench tasks with small dewars Wrist-length gloves for dexterity and safety glasses that fit over prescription frames. Before every use Check gloves for cracks, splits, thinning and opened seams. Replace scratched or cloudy visors. Store PPE dry and away from the vessel neck. Full guide: https://cryolab.co.uk/liquid-nitrogen-gloves-face-shields-aprons/
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Cryogenic Labels That Last: A Checklist for Straws, Vials and Canes

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A quick checklist for anyone responsible for what goes into long-term cryogenic storage. 1. Use labels made for cryogenic temperatures Ordinary adhesives turn brittle and lift after repeated removal from the vessel. 2. Label before freezing At room temperature, on a clean, dry surface, pressed down along the whole length. 3. Print where you can Printed labels are more legible than handwriting and can carry a barcode. 4. Put the right information on Two unique identifiers, sample number, freezing date and sample type. 5. Label the containers too Goblets, visotubes, canes, canisters and the vessel should all match the inventory. 6. Check and reconcile Read labels back before freezing and audit the store against the database regularly. Full guide: https://cryolab.co.uk/labelling-cryo-straws-and-vials/
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ICSI, Holding, Biopsy and Denudation Pipettes: A Standardisation Checklist for IVF Laboratories

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A short checklist for laboratory managers who want micromanipulation pipettes under control without arguing every embryologist out of their favourite. 1. List what is actually in use For each technique and each rig, note the inner diameter, bevel and bend angle in use today. 2. Check the rigs, not the people Different bend angle preferences on the same rig often point to differences in tool holder or dish set-up. 3. Write one specification per pipette type per rig Allow a small number of documented alternatives where there is a clear reason. 4. Record lot numbers At goods-in and against each case, so a problem lot can be traced and quarantined. 5. Inspect new deliveries Check tips and bends under the microscope before a new lot goes into routine use. 6. Review once a year Bring outliers into line and check outcome data against pipette changes. Full guide: https://cryolab.co.uk/micromanipulation-pipettes-ivf-team/
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On-Site Liquid Nitrogen: Reservoir Size, Dispensing Without Pouring and Safe Routes

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The liquid nitrogen inside your building is a supply chain of its own: a bulk reservoir, a way of getting liquid out of it, and a route to every vessel it feeds. Get those three right and the store stays topped up even when deliveries are infrequent. Reservoir size Work from consumption. Add weekly use for every vessel and freezer, multiply by the delivery interval, add at least one missed delivery, and include the reservoir's own static loss. Self-pressurising tanks in the 100 to 500 litre range typically lose between 0.8% and 1.2% of their contents a day. Dispensing without pouring A self-pressurising tank delivers liquid through a hose at a controlled rate, from above 5 litres per minute on a 100 litre tank to above 15 litres per minute on the largest. A dewar with a foot pumped dispenser does the same for smaller rooms. Both remove the tipping that causes splash injuries. Safe routes A full 500 litre tank weighs over 670 kg, so check floors, ramps and thresholds. Avoid small en...
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