DSIP On Arrival: What to Check and Do First

When a DSIP order arrives, check that each vial’s seal and cap are intact and that the contents look like a dry white cake or powder, then put the sealed vials in the fridge for near-term use or the freezer for longer holding, boxed and dark. Lyophilised DSIP is a dry, chemically simple material, so it does not need an ice pack in transit. The ready-mixed spray goes straight into the fridge.

Why DSIP travels without ice

A lyophilised vial contains the peptide as a freeze-dried cake with almost no water. The slow routes that matter for DSIP in solution, oxidation of its N-terminal tryptophan and change at its single aspartate, need a mobile, dissolved molecule and, for the aspartate, water to proceed (Geiger and Clarke, Journal of Biological Chemistry, 1987). In the dry, sealed state they have very little to work with.

The supplier figures show how little happens to the dry cake. Cayman rates solid DSIP at minus 20 °C at 4 years or more (Cayman Chemical, item 34426). InvivoChem gives its powder 2 years at 4 °C and 3 years at minus 20 °C, and states that it is stable at ambient temperature for a few days during ordinary shipping (InvivoChem, V64516). DSIP also has no methionine, cysteine or histidine to oxidise and no asparagine or glutamine to deamidate.

Every Vistara Labs order ships from within Canada by Canada Post Xpresspost, so the vials stay in the domestic network without a customs hold. A few days at room temperature in transit does not harm sealed DSIP powder. An ice pack would add condensation risk inside the parcel without protecting anything.

What to check, vial by vial

The seal and cap

Each vial should have its crimped aluminium seal intact and the plastic flip-off cap in place over the rubber stopper. The cap protects the stopper surface from dust and handling. A cap that has popped off in transit does not by itself mean the vial is open; the crimp and stopper are the actual closure. If the crimp is loose or the stopper is visibly pushed in or pierced, contact us before using the vial. An intact closure keeps both moisture and fresh air away from the cake.

The glass

Look for cracks or chips, especially around the neck. Intact glass and an intact crimp mean the vial is sealed.

The cake or powder

Lyophilised DSIP is white to off-white. A 5 mg fill is a small amount of material, so expect a compact cake or pellet at the bottom of the vial, not a full plug. It is normal for:

• the cake to have shrunk away from the glass or cracked into pieces;
• the cake to have broken up into loose powder that moves when the vial is tilted;
• powder to be scattered up the walls or on the underside of the stopper after travel.

None of these affect the peptide. Freeze-dried cakes are fragile and shift with handling. Tap the vial gently on the bench to settle the powder before reconstituting.

What would warrant a question is a cake that looks wet, syrupy or collapsed into a glassy film, or that has a yellow or brown tint. Wetness suggests moisture got in. A tint matters more for DSIP than for most peptides, because the photo-oxidation products of tryptophan are yellow (Dyer et al., Photochemical and Photobiological Sciences, 2006).

The nasal spray

The DSIP Nasal Spray is different: it arrives ready-mixed in sterile saline in a sealed metered pump. Because it is already a solution, it goes into the fridge upright and dark as soon as it arrives. It should be clear and colourless. See how to store a peptide nasal spray.

What to do first

1. Leave the vials sealed. Do not open or reconstitute a vial until it is needed. The dry cake is the most stable form DSIP will ever be in.
2. Decide fridge or freezer. Vials for use in the coming weeks go in the fridge at 2 to 8 °C. Vials to be held for months go in the freezer at minus 20 °C, the condition for the supplier’s longest powder figures. The full windows are on how long DSIP lasts.
3. Keep them boxed and dark. Store vials in their box in the main body of the fridge or freezer, not in the door. Both suppliers specify storage away from light.
4. Store the bacteriostatic water separately. Unopened bacteriostatic water keeps at room temperature; once its stopper has been pierced it is kept cool and used within its own window.
5. When you are ready to mix, let the vial warm to room temperature before piercing it so condensation does not form on the powder. The method is on the DSIP handling page and the volumes on the DSIP reconstitution page.

If the parcel sat somewhere warm

A parcel left in a mailbox or a warm vehicle for an afternoon is not a problem for sealed lyophilised DSIP, for the reasons above. Move the vials to cold, dark storage when you get them and proceed as normal. A mixed vial or the ready-mixed spray is different, because it is already in solution; those should be refrigerated promptly and kept out of the light.

More on DSIP

How the peptide holds up over time is on the DSIP stability page. Our certificates are on the lab reports page.