NAD+ is supplied in more than one format, and the format changes what a certificate has to report more than the compound does. A lyophilised vial, a solution and a cast film are three different manufacturing problems carrying three different specifications.
This guide covers what each format commits to, what its certificate should show, and how to choose between them on something other than convenience.
One compound that is not a peptide
NAD+ sits in a peptide catalogue because buyers ask for it alongside peptides, not because it is one. It is a dinucleotide, and that matters for documentation: purity by a peptide-oriented method means something different, and net peptide content is meaningless for a molecule that is not a peptide.
The first question about any catalogue item is therefore what class of material it is, because that determines which fields on a certificate carry weight. Not everything in a peptide catalog is a peptide covers reading a certificate against the molecule it describes.
The three formats, compared
| Lyophilised vial | Solution or spray | Dissolving strip | |
|---|---|---|---|
| Key specification | Content per vial | Concentration | Content uniformity per unit |
| Water present | Removed by drying | Present from manufacture | Low, but the film is exposed |
| Usable life | Longest | Shortest | Depends on pack integrity |
| Main risk | Moisture ingress through the closure | Solution-phase degradation | Humidity and uneven casting |
| Clock starts | At reconstitution | At manufacture | At first opening of the pack |
| Certificate focus | Identity, purity, content | Identity, purity, concentration | Identity, purity, uniformity |
The compound is the same. What changes is what the manufacturing has to control and therefore what the certificate has to report.
What the vial certificate should show
Identity, purity with its method named, and content as a measured mass rather than the nominal label figure. The vial is the format where the usual certificate reading applies most directly, covered in reading a certificate of analysis line by line.
It is also the format with the longest usable life, because lyophilisation removed the water that most degradation routes need. Lyophilisation explained covers why that matters and residual moisture covers the water that stays behind.
What a solution or spray certificate should show
Concentration measured rather than formulated, identity on the same terms as any other material, and purity read with the understanding that solution-phase degradation has already had time to occur between manufacture and delivery.
A metered spray adds its own specification: the volume delivered per actuation, with a tolerance, measured across the life of the container. Where that figure is unavailable, you know the concentration and not the delivered amount, which are different things. Nasal sprays and liquid formats covers the format in full.
What a strip certificate should show
Content per strip with the method named, and a uniformity result stating how many units were tested. A strip is a cast film and the active material has to be distributed evenly through it before it dries, which makes uniformity the specification rather than a secondary check.
Uniformity does not transfer between batches, because casting conditions vary. That makes lot-level documentation matter more than usual here. Dissolvable strips explained covers why.
Choosing between them
- Take the vial when material will sit for months, or when you need a concentration the manufacturer did not choose.
- Take a solution when the stated concentration is the one you want and the material will be used soon, since removing a reconstitution step removes a source of error.
- Take strips where a fixed unit quantity is the point and the pack will be consumed rather than stored open.
None is better. They are different trades, and the right one depends on how quickly material is actually consumed, which your usage records answer rather than a supplier.
Storage, by format
The sealed vial is the most forgiving and the clock starts when you reconstitute it. A solution arrives with its clock already running, so refrigerate on arrival rather than later in the day. A strip pack is a barrier that part-use compromises, so the usable life should run from first opening rather than from delivery.
All three benefit from being kept closed and dark, and how peptides degrade covers the routes that light and oxygen feed even for a non-peptide molecule.
What to record
- The format, since it determines which specification applies.
- The lot and your own copy of the certificate.
- For a vial, the measured content and the reconstitution details.
- For a solution or strip pack, the date of first opening.
Scope
NAD+ in every format here is supplied for laboratory research only. Nothing in this guide describes effects in any organism, and nothing on a certificate speaks to them.
In short
One compound, three manufacturing problems. The vial is documented by content, the solution by concentration, the strip by uniformity. Match the format to how quickly you will actually use it, and read each certificate against the specification that format commits to.
Comparing suppliers across formats
A supplier strong on one format is not automatically strong on another, because the manufacturing problems differ. A vial is a fill operation; a solution is a formulation; a strip is a casting process. Each has its own failure modes and its own specification.
Ask which format a supplier actually manufactures rather than packages, because that usually explains which of their certificates are most complete. Comparing suppliers on documentation covers scoring the answers.
Why purity means something different here
Purity by a reversed-phase method is reported as a ratio of peak areas among the species the detector sees at a chosen wavelength. For a molecule that is not a peptide, both the method and the wavelength may need to differ from the peptide default, and a certificate inheriting the peptide template is answering the wrong question.
Check that the method named suits the molecule rather than the catalogue. HPLC purity covers what an area percent figure actually is and what it excludes.
What to check on arrival, by format
- Vial: lot against certificate, cake intact, no visible liquid.
- Solution: lot against certificate, seal intact, refrigerate immediately rather than later in the day.
- Strips: pack sealed, strips not stuck together or deformed, which both suggest humidity in transit.
Receiving and inspecting a peptide shipment covers the general protocol, and the format-specific checks sit inside it.
Choosing on consumption rather than preference
The question that settles format is how quickly the material will actually be used, which your own usage records answer and a supplier cannot. A format with a shorter usable life is a good choice for fast consumption and an expensive one for slow consumption.
Inventory levels and reorder points covers deriving consumption from measurement rather than estimate, which is the input this decision needs.
Where this sits
For the liquid format in general, nasal sprays and liquid formats. For strips, dissolvable strips explained. For why a catalogue mixes molecule classes at all, not everything in a peptide catalog is a peptide.
Building the habit
The checks in this guide take minutes and they only work if they happen every time rather than when someone remembers. Two things make that realistic: a named person who owns receiving, and a form short enough that a busy day does not defeat it.
Writing an SOP for peptide receipt and storage covers turning the checks into something a practice actually follows, and chain of custody inside a practice covers the four points where the record usually breaks.
A note on comparing prices across formats
Price per unit is not comparable between a vial, a spray and a pack of strips, because the units are different things. The honest comparison is cost per unit of work, which requires knowing how much of each format a piece of work actually consumes.
That calculation usually favours the vial for anything slow-moving and the prepared formats for anything fast and repetitive, which is the same conclusion the usable-life argument reaches from the other direction.
What stays constant across formats
Identity and purity are questions about the molecule and are asked the same way whichever format it arrives in. What changes is the third number: content for a vial, concentration for a solution, uniformity for a strip.
Reading the quote
A wholesale quote carries four things: a unit price, a minimum quantity, the documentation included with the order, and the terms under which you pay. Only the first is read closely by most buyers and it is the one that tells you least about what the order will actually cost.
Documentation is the line that separates two identical-looking quotes, and terms change the real price more than the unit price does. Thirty days to pay on a four-figure order is worth roughly a month of the cost of capital. How to read a wholesale peptide quote takes all four apart.
Across formats there is a further complication: the four lines of a quote mean different things for a vial, a solution and a pack of strips, so two quotes in different formats are not directly comparable even before documentation is considered.
A short pre-order checklist
Five questions, one email, about fifteen minutes. Can you send the certificate for a lot I would actually receive. Which laboratory issued it and what is it accredited for. Which salt form is supplied. What is the lead time for in stock against made to order. And what happens if a lot is withdrawn after I have taken delivery.
The answers matter and so does how they arrive: how quickly, whether they address what was asked, and whether they come from someone who can see the document rather than relaying it. Auditing a peptide supplier is the longer version, and comparing suppliers on documentation covers weighing the replies against each other.
For where this sits among the other molecules and formats a catalogue carries, not everything in a peptide catalog is a peptide covers how the classes differ.