Every vial that leaves our facility is documented the same way: a measured mass of peptide, a certificate of analysis, and nothing else. Turning that vial into a working solution is arithmetic, but arithmetic done under time pressure is where bench errors come from. The research calculator exists to make that step boring and checkable.
It is a laboratory solution-math tool. You tell it how much peptide is in the vial, how much solvent you added, and how much material each assay consumes. It returns the concentration you now have, the volume that delivers your target amount, and how long the vial will last at your planned throughput.
What the calculator is, and what it is not
The tool answers preparation questions only. It is not a protocol, not a prescription, and not a substitute for your institution’s validated procedures.
- It converts mass, volume and concentration, and projects vial life at your stated throughput.
- It works in laboratory units only: milligrams, millilitres, micrograms, microlitres.
- It does not ask for, or use, body weight, and it never suggests an amount to give, a route, a schedule or a syringe volume.
- It holds no personal or order data, and every figure is recomputed from the numbers you type.
The five fields, one at a time
- Product — pick the catalogue item and size. The vial mass fills in automatically so the calculator starts from the same number your COA documents.
- Peptide in vial (mg) — the total mass of peptide in the vial. Editable, because not every preparation uses a whole vial.
- Solvent volume added (mL) — the volume you reconstitute into, for example sterile or bacteriostatic water for laboratory use.
- Target amount per assay (µg) — how much peptide one assay well or reaction should receive.
- Assays per day (test runs) — your planned daily throughput, used only to project how many days the vial covers.
The product list is generated live from the research catalogue, so anything we publish that carries a milligram size appears in the dropdown without a code change. Sizes that are not expressed in milligrams — a 10 mL bottle of bacteriostatic water, for instance — are left out, because there is no peptide mass to divide.
Two formulas do all the work
Nothing hidden sits behind the results. Two lines of arithmetic produce every number on screen:
Concentration = peptide (µg) ÷ solvent (mL)Volume per assay = target amount (µg) ÷ concentration (µg/µL)Two further lines cover vial life. Assays per vial is the total micrograms divided by the target per assay, rounded down — a partial assay is not an assay. Days per vial is that figure divided by your assays per day, again rounded down.
One unit fact is worth memorising, because it catches most transcription errors: a solution that reads X mg/mL also reads X µg/µL. The two columns the calculator shows side by side are the same number in two unit systems, so if they ever disagree you have typed something wrong.
A worked example
Take a 10 mg vial reconstituted in 2 mL of solvent, with each assay needing 100 µg and three assays run per day:
| Total peptide | 10,000 µg |
|---|---|
| Concentration | 5 mg/mL — the same solution is 5 µg/µL |
| Volume per assay | 20 µL |
| Material used per day | 300 µg · 60 µL |
| Assays per vial | 100 |
| Days of testing per vial | 33 |
Read the 20 µL line back by hand to see how checkable this is: 10 mg is 10,000 µg, spread through 2 mL gives 5,000 µg per mL, which is 5 µg per µL. An assay that needs 100 µg therefore takes 100 ÷ 5 = 20 µL. The calculator is showing you long division, not a black box.
Why the same question gets asked in three ways
Changing the solvent volume is the field that moves everything else. Doubling the solvent halves the concentration and doubles the volume drawn per assay, while assays per vial stay put — the mass in the vial has not changed. That is the distinction the results panel keeps visible: how much material you consume, and how much liquid you pipette, are separate questions with separate answers.
Target amount per assay behaves the same way. Halve it and the volume per assay halves, and the vial supports twice as many runs. Teams planning a long plate series usually set the target first, then choose the solvent volume that makes the pipetted volume comfortable to measure accurately — very small draws are where precision is lost.
How to use it responsibly at the bench
- Start from the COA figure for your lot, not from the label of a similar product.
- Record the solvent volume you actually added. Headspace and residue mean the delivered volume is not always the volume you drew.
- Recompute one result by hand, or with a second method, before committing a plate.
- Keep the calculator output in your lab notebook alongside the lot number, so a run is reproducible months later.
- Treat every output as an input to your own validated procedure, never as a substitute for one.
Where to verify the numbers
The mass the calculator assumes comes from the same documentation we publish. Certificates of analysis are archived by product with their accession number, lot code, analysis date and reported purity, so the starting figure in any calculation can be traced back to a specific vial.
- Published COA for every catalogue product
- Direct from manufacturer to researcher
- United States based, worldwide shipping
