Across this catalogue most compounds are supplied in more than one format. The material is the same. What changes is how many preparation steps sit between the container and the bench, and how repeatable each withdrawal is.

The three formats

Lyophilised vial

A stoppered glass vial holding freeze-dried peptide. It requires reconstitution with a suitable solvent before use, and each withdrawal is made through the stopper. It is the most flexible format: the concentration is whatever you choose to make it, which matters when a protocol calls for a specific one.

Refill cartridge

The same material in a cartridge that loads directly into the reusable metal dispensing pen. It removes the transfer step between container and dispenser.

Pre-filled dispensing pen

Arrives ready to dispense, with graduated increments. No reconstitution, no transfer, and the material stays sealed from the point of filling until it is dispensed.

What actually differs

	Vial	Refill cartridge	Pre-filled pen
Reconstitution needed	Yes	No	No
Concentration	You set it	As supplied	As supplied
Dispensing	Manual withdrawal	Graduated, via pen	Graduated, via pen
Repeat access	Through the stopper	Sealed cartridge	Sealed cartridge
Hardware required	None	Reusable pen	None

Choosing between them

A vial suits work where the concentration is a variable. If the experimental design specifies a concentration, or several concentrations are being compared, starting from lyophilised powder is the only format that gives that control.

A pen suits work where repeatability matters more than flexibility. Graduated dispensing from a sealed cartridge removes two sources of variation: the reconstitution step and repeated withdrawal through a stopper.

A refill cartridge suits an established pen workflow. It is the same material at the same loading as the pen, for a bench that already has the hardware.

Formats are separate catalogue entries

Each format is listed as its own entry with its own price and its own batch documentation, rather than as an option on a single product page. The pre-filled pen collection and the refill cartridge collection group them by format; each also appears in its own research pathway.

The reconstitution calculator works out the resulting concentration for a given vial strength and solvent volume.