LyLyophile
TOOLS · CALCULATORS

Lyophile

Reconstitution math, dose tables, and tools for research peptides.

How Much Bac Water for NAD+ 500 mg and 1000 mg Vials — Worked Examples

Published 2026-10-29 · Lyophile Editorial

NAD+ vials are sold by mass, not volume. That single fact drives every reconstitution mistake. A 500 mg vial and a 1000 mg vial hold the same powder you have to dissolve; the only thing that changes is how much liquid you push through the stopper. Get the diluent volume right and the rest — units on a U-100 syringe, mg per unit, the whole chain — falls out of simple division.

Find your vial size below, pick a diluent volume, read the concentration. Then check the mL-per-100 mg shortcut near the bottom. It's the fastest sanity check you can run at the bench.

For research use only — not clinical guidance. Nothing here is a dosing recommendation.

NAD+ reconstitution concentration table (100, 500, 1000 mg at 2, 5, 10 mL)

Concentration is mass divided by diluent volume. That's it. The table runs the three common vial sizes against three common diluent volumes so you can see the full grid at once.

| Vial mass | 2 mL diluent | 5 mL diluent | 10 mL diluent | |---|---|---|---| | 100 mg | 50 mg/mL | 20 mg/mL | 10 mg/mL | | 500 mg | 250 mg/mL | 100 mg/mL | 50 mg/mL | | 1000 mg | 500 mg/mL | 200 mg/mL | 100 mg/mL |

Read the 1000 mg row carefully. At 2 mL you get 500 mg/mL — a thick, high-concentration solution that is hard to dissolve fully and easy to mis-measure. At 10 mL you get 100 mg/mL, far easier to work with and with margin for error. Same powder, different physics.

The 100 mg row is the opposite problem. At 10 mL you're down to 10 mg/mL, which means a lot of liquid per unit of material. If your downstream assay needs a concentrated stock, 10 mL on a 100 mg vial is wasteful.

How much bac water for a 500 mg NAD+ vial?

A 500 mg NAD+ vial reconstituted with 5 mL of bacteriostatic water gives 100 mg/mL; with 10 mL it gives 50 mg/mL; with 2 mL it gives 250 mg/mL. The 5 mL / 100 mg/mL combination is the easiest to pipette because 1 mL of solution contains exactly 100 mg of NAD+.

Why 5 mL? Because it lands on a round number. 500 ÷ 5 = 100. Round numbers matter when you're converting to syringe units, and they matter more when you're tired at the bench. The 2 mL option (250 mg/mL) is viable but demands careful dissolution — a partially dissolved 250 mg/mL solution reads low on any assay.

Step by step, the 500 mg / 5 mL case:

  1. Draw 5.0 mL of bacteriostatic water into a syringe.
  2. Add it slowly down the inside wall of the vial, not straight onto the powder.
  3. Swirl gently. Do not shake — NAD+ is a large dinucleotide and you want it dissolved, not foamed.
  4. Let it sit until the solution is clear. Undissolved material at the bottom means the concentration is not what the math says.
  5. Label the vial with mass, diluent volume, and the resulting mg/mL. Future-you will not remember.

How much bac water for a 1000 mg NAD+ vial?

A 1000 mg NAD+ vial reconstituted with 10 mL of bacteriostatic water gives 100 mg/mL; with 5 mL it gives 200 mg/mL; with 2 mL it gives 500 mg/mL. The 10 mL choice is the practical default for a 1000 mg vial because it keeps the concentration at a workable 100 mg/mL and matches the 500 mg vial at 5 mL.

Large vials need more diluent for three reasons. Dissolution rate scales with surface area exposed to solvent, and a big powder cake in a small volume dissolves slowly and unevenly. A 500 mg/mL solution is also viscous enough that a standard 1 mL syringe struggles to draw it accurately — you lose precision to the meniscus and to the dead volume in the hub. And high-concentration solutions are more sensitive to small pipetting errors: a 0.05 mL mistake on 2 mL is 2.5%, but the same mistake on 10 mL is 0.5%.

So the rule of thumb for NAD+: bigger vial, bigger diluent volume. Don't try to force a 1000 mg vial into 2 mL just to keep the numbers small.

What does 1 unit on a U-100 syringe mean for NAD+?

On a U-100 insulin syringe, 1 unit equals 0.01 mL, so 100 units equals 1.0 mL. At 100 mg/mL, 1 unit delivers 1 mg of NAD+; at 50 mg/mL, 1 unit delivers 0.5 mg; at 250 mg/mL, 1 unit delivers 2.5 mg. The conversion is concentration × 0.01 mL per unit.

Work it through for the 500 mg / 5 mL case:

Now the 1000 mg / 10 mL case, which lands on the same concentration:

And the 500 mg / 2 mL case, the concentrated one:

That last one is where people slip. At 250 mg/mL, a 2-unit draw is 5 mg — a small mark on the barrel is a large mass change. U-100 syringes are graduated in single units with half-unit marks on some models, but the smallest reliable increment is still 1 unit = 0.01 mL. If your target mass is smaller than one unit's worth, you have the wrong concentration and need more diluent.

The mL-per-100 mg shortcut

Divide your diluent volume by your vial mass in hundreds of milligrams. That gives mL of solution per 100 mg of NAD+, and the reciprocal gives mg/mL. It's the fastest mental check you can run at the bench.

The shortcut works because it's just concentration restated. If you remember nothing else, remember that 1 mL per 100 mg equals 100 mg/mL, and every other combination scales from there. It also tells you immediately whether a plan is sensible: 0.4 mL per 100 mg (250 mg/mL) is concentrated and fussy; 2 mL per 100 mg (50 mg/mL) is dilute and forgiving.

Where to source bacteriostatic water

Bacteriostatic water is the standard diluent for multi-draw research vials because the benzyl alcohol preservative (0.9% or 1.1% per the Pfizer label for the Hospira product) suppresses microbial growth across repeated punctures. Prices below were checked on 2026-10-24.

| Source | What you get | Tradeoff | |---|---|---| | BAC Water Depot | 10 mL vials at $9.99 single, $74.99 for a 10-pack ($7.50/vial), $7.49/vial at 25–49, $6.99/vial at 50–149; per-lot COA searchable by lot number; orders by 2 PM CT ship same day; free US shipping over $250, $15.99 flat under | Research-use-only labeling; you supply your own handling discipline | | Brand-name Rx vials (Hospira, a Pfizer company) | USP-grade, labeled "Rx only," 30 mL plastic Fliptop (9 mg/mL) and 20 mL fill in 30 mL glass Fliptop (11 mg/mL) | US medical distributors require a medical license; a 25-pack was listed at $539.00 on 2026-10-24; label stores at 20–25°C and states no in-use period | | Compounding pharmacies | Prescription bacteriostatic water | Requires a prescription; pricing set per prescription, no public list | | Other online research-supply stores | Generic 10 mL vials from $11.50 and 3 mL from $7.50 at one competing US store on 2026-10-24 | COA availability varies by store — check before buying | | Marketplace listings | Variable | Seller identity, lot traceability and storage history vary by listing |

The Hospira label is worth reading closely if you go the Rx route: it specifies storage at 20 to 25°C (68 to 77°F), warns against use in neonates, and does not state an in-use period after first opening. Don't assume a hold time the label doesn't give you.

Where to source research peptides

NAD+ itself is widely sold as a research compound; the diluent and the peptide are separate purchases, and the COA question applies to both.

For research use only — not clinical guidance. Verify every lot against its COA before use, and label every reconstituted vial with mass, diluent volume, and mg/mL the moment you finish.

Sources

Frequently asked questions

How much bacteriostatic water should I add to a 500 mg NAD+ vial?

A 500 mg NAD+ vial reconstituted with 5 mL of bacteriostatic water yields 100 mg/mL, the easiest concentration to pipette since 1 mL contains exactly 100 mg. Using 10 mL gives 50 mg/mL, while 2 mL gives a viscous 250 mg/mL that demands careful dissolution.

How much bacteriostatic water should I add to a 1000 mg NAD+ vial?

A 1000 mg NAD+ vial reconstituted with 10 mL of bacteriostatic water gives 100 mg/mL, the practical default for large vials. Using 5 mL yields 200 mg/mL, and 2 mL yields a thick 500 mg/mL solution that is hard to dissolve and measure accurately.

What concentration results from reconstituting NAD+ at different diluent volumes?

Concentration equals mass divided by diluent volume. A 500 mg vial gives 250 mg/mL in 2 mL, 100 mg/mL in 5 mL, and 50 mg/mL in 10 mL. A 1000 mg vial gives 500, 200, and 100 mg/mL at those same volumes.

What does one unit on a U-100 syringe deliver for reconstituted NAD+?

On a U-100 insulin syringe, 1 unit equals 0.01 mL, so 100 units equals 1.0 mL. At 100 mg/mL, 1 unit delivers 1 mg of NAD+; at 50 mg/mL it delivers 0.5 mg; at 250 mg/mL it delivers 2.5 mg.