Why use bacteriostatic water instead of plain sterile water?

Bacteriostatic water (BAC water) contains a small amount of benzyl alcohol — typically 0.9%. This acts as a preservative, stopping bacteria from growing in the vial after you open it. Plain sterile water has no preservative, so once the seal is broken it becomes a contamination risk quickly. BAC water gives you a much longer, safer working window for multi-draw research vials.

How much BAC water should I add to my DSIP vial?

It depends on the concentration you want. Adding 1 mL to a 5 mg vial gives you 5,000 mcg per mL, making dose maths simple. Adding 2 mL gives 2,500 mcg per mL. Use the calculator on this site to work out the exact volume you need to draw for a specific microgram dose, whichever dilution you choose.

What does DSIP actually do, according to research?

DSIP is a nine-amino-acid peptide studied for its influence on delta (deep) sleep, neurotransmitter levels, thermoregulation, heart rate, and pain thresholds. Research suggests it may also interact with hormonal systems. Its full mechanism of action is still not fully understood — researchers describe it as a peptide with broad but not yet fully mapped biological activity.

How long does reconstituted DSIP stay usable?

When stored in a refrigerator at 2–8 °C and protected from light, most reconstituted peptide solutions remain stable for up to 30 days. The dry, unreconstituted powder lasts much longer when kept frozen. Always check the product-specific guidance from your supplier and discard any solution that looks cloudy or discoloured.

How to Reconstitute DSIP Peptide – Step-by-Step

What Is DSIP, Anyway?

DSIP stands for Delta Sleep-Inducing Peptide. It is a tiny molecule — just nine amino acids long — first isolated from rabbit blood in 1977. Researchers have since studied it for its potential role in sleep, stress response, and a surprisingly wide range of other physiological effects.^[6] Scientists still debate exactly how it works, which is part of what makes it such an interesting research subject.^[1]

Before you can use DSIP in any research setting, you need to reconstitute it. That just means turning the dry powder in the vial into a liquid solution. Think of it like dissolving a stock cube — the steps matter.

What You Will Need

Your DSIP vial (lyophilized powder)
Bacteriostatic water (called BAC water) — this is sterile water with a tiny amount of benzyl alcohol that stops bacteria growing
A 1 mL syringe with a fine needle
Alcohol swabs
A clean, well-lit workspace

Step 1 — Warm the Vial First

Take the DSIP vial out of the fridge and let it sit at room temperature for about ten minutes. A cold vial can cause the powder to clump when liquid hits it. Warming it gently helps everything dissolve evenly. Do not use heat — just leave it on the bench.

Step 2 — Swab Everything

Wipe the rubber stopper on the DSIP vial and the stopper on your BAC water vial with a fresh alcohol swab. Let them air-dry for a few seconds. This keeps contaminants out — a small step that matters a lot.

Step 3 — Draw Your BAC Water

Insert your syringe needle through the rubber stopper of the BAC water vial. Pull back the plunger to draw the amount of water you need. The most common starting volume is 1 mL, though the exact amount depends on the dose you are targeting for your research protocol. More on that in Step 5.

Step 4 — Add the Water Slowly — This Is the Important Part

Point the needle at the glass wall of the DSIP vial, not straight down into the powder. Then push the plunger very slowly so the water trickles down the side. Why? Blasting liquid directly onto a delicate peptide can break the molecular structure — a process called denaturation. Think of it like pouring boiling water onto a chocolate bar versus letting it melt gently.

DSIP is a small, relatively stable nonapeptide^[6], but treating it gently during reconstitution is good research practice regardless.

Step 5 — Swirl, Don't Shake

Once the water is in, swirl the vial slowly between your fingers in a circular motion. Do this for twenty to thirty seconds. You should see the powder dissolve into a clear, colourless solution. If you see floating particles or cloudiness after a full minute of swirling, something is off — do not use the solution.

Never shake the vial vigorously. Shaking creates tiny bubbles and mechanical stress that can degrade peptide bonds.

Step 6 — Calculate Your Dose With the Calculator

Now your solution is ready, but you need to know how much to draw for any given research dose. This is where maths can trip people up. If you dissolved a 5 mg vial in 1 mL of BAC water, your concentration is 5 mg per mL — or 5,000 micrograms per mL. Use the calculator to convert your target dose in micrograms into the exact volume in millilitres. This removes guesswork entirely.

Researchers have noted that DSIP shows a U-shaped activity curve — meaning the dose and timing both influence results.^[6] Accurate measurement is therefore especially important when planning any research protocol.

Step 7 — Store It Correctly

Reconstituted DSIP should go straight into the fridge at 2–8 °C. Keep it away from light. Most researchers use reconstituted peptide solutions within 30 days, though always follow the guidance that came with your specific product.

If you have leftover unreconstituted vials, keep them in the freezer until needed. The dry powder is far more stable than the liquid solution.

A Quick Note on the Research Context

DSIP has been studied since the 1970s for effects that go well beyond sleep — including changes in heart rate, blood pressure, thermoregulation, and pain threshold.^[5] More recent work has explored fusion peptides designed to cross the blood-brain barrier more efficiently.^[3] It remains, in the words of one review, "a still unresolved riddle"^[1] — which is precisely why careful, well-documented research technique matters.

This guide is for research and educational purposes only and does not constitute medical advice.

Sources

Delta sleep-inducing peptide (DSIP): a still unresolved riddle. — Journal of neurochemistry, 2006. PMID 16539679.
[DSIP: the sleep peptide or an unknown hypothalamic hormone?]. — Zhurnal evoliutsionnoi biokhimii i fiziologii, 1994. PMID 7817664.
Pichia pastoris secreted peptides crossing the blood-brain barrier and DSIP fusion peptide efficacy in PCPA-induced insomnia mouse models. — Frontiers in pharmacology, 2024. PMID 39444618.
Delta-sleep-inducing peptide (DSIP): an update. — Peptides, 1986. PMID 3550726.
DSIP--a tool for investigating the sleep onset mechanism: a review. — The International journal of neuroscience, 1988. PMID 3286557.
Delta-sleep-inducing peptide (DSIP): a review. — Neuroscience and biobehavioral reviews, 1984. PMID 6145137.

How to Reconstitute DSIP: A Friendly Step-by-Step Guide