CJC-1295 Reconstitution Calculator

Use this free calculator to reconstitute CJC-1295 for research: enter the milligrams in your vial and the millilitres of bacteriostatic water, and it returns the concentration in mg/mL, the volume to draw for any target, and the U-100 unit equivalent. The reference data and concentration matrix below are specific to CJC-1295 and can be checked by hand or cited.

CJC-1295 reference data

Class	Long-acting GHRH analog (modified GRF 1-29 with DAC / maleimidopropionyl albumin-binding linker)
Molecular formula	C165H269N47O46
Molecular weight	3647.2 g/mol (DAC form; non-DAC ~3368 — see notes)
CAS	446262-90-4
PubChem CID	91971820
Typical vial sizes	2 mg / 5 mg
Storage	Lyophilized: -20 C sealed and desiccated, out of light. Reconstituted: 2-8 C, protect from light; typical ~4-week refrigerated working window.

Molecular weight and nmol/mL are for the DAC form (CID 91971820). The non-DAC “mod GRF 1-29” variant is a different molecule (~3368 g/mol); for it, multiply nmol/mL by ~1.08. Confirm which form your vial is before mass calculations.

Concentration matrix for CJC-1295

Each cell = concentration for that vial mass and diluent volume, with mcg per U-100 unit and nmol/mL (from MW 3647.2). Concentration = vial mg ÷ water mL.

Vial ↓ / Water →	1 mL	2 mL	3 mL	5 mL
2 mg	2.00 mg/mL 20.0 mcg/unit · 548 nmol/mL	1.00 mg/mL 10.0 mcg/unit · 274 nmol/mL	0.67 mg/mL 6.7 mcg/unit · 183 nmol/mL	0.40 mg/mL 4.0 mcg/unit · 110 nmol/mL
5 mg	5.00 mg/mL 50.0 mcg/unit · 1371 nmol/mL	2.50 mg/mL 25.0 mcg/unit · 685 nmol/mL	1.67 mg/mL 16.7 mcg/unit · 457 nmol/mL	1.00 mg/mL 10.0 mcg/unit · 274 nmol/mL

Handling & notes

Water-soluble; the peptide generally dissolves easily and stays clear, and it does not typically gel or clump the way some other peptides can. Plain bacteriostatic water is sufficient — no acidified diluent or co-solvent is needed.

The DAC / non-DAC distinction matters for every number on this page. The molecular weight above (3,647.2 g/mol, PubChem CID 91971820) is the DAC form, which carries a maleimidopropionyl albumin-binding linker. The non-DAC variant sold as "modified GRF (1-29)" is a different molecule at roughly 3,368 g/mol. Mass concentration in mg/mL is identical for both — that is pure arithmetic on the vial label — but the molar column is not. For the non-DAC form, multiply the nmol/mL values in the matrix above by about 1.08. Confirm which form the vial contains before using any molar figure.

Technique. Add the diluent slowly against the vial wall and let it sit for a minute or two to dissolve fully. Swirl or roll rather than shaking: shaking foams the solution, and foaming stresses the peptide at the air-liquid interface. If the solution stays cloudy and will not clear, discard it.

Storage. Lyophilized at -20 C, sealed and desiccated, out of light. Reconstituted at 2-8 C away from direct light, with a typical working window of about four weeks — some references suggest a shorter window for best stability. Discard the solution if it turns cloudy or discolored or shows floating particles.

Worked example: CJC-1295

A 5 mg vial reconstituted with 2 mL of bacteriostatic water:

Concentration: 5 mg ÷ 2 mL = 2.50 mg/mL
Per U-100 unit (1 unit = 0.01 mL): 2.50 mg/mL × 0.01 mL = 0.025 mg = 25 mcg per unit
Molarity, DAC form: (2.50 ÷ 3,647.2) × 1,000,000 = 686 nmol/mL
Molarity, non-DAC (~3,368 g/mol): (2.50 ÷ 3,368) × 1,000,000 = 742 nmol/mL — the ~1.08× correction in practice
Total yield: 2.00 mL of solution = 200 U-100 units in the vial

Note that the two molar figures differ by 8% while the mg/mL and mcg-per-unit figures are identical. That is the entire practical consequence of the DAC linker for reconstitution math.

CJC-1295 reconstitution FAQ

What is the difference between CJC-1295 with DAC and without?
DAC is a drug-affinity-complex linker (maleimidopropionyl) bound to the peptide, making it a heavier, distinct molecule at about 3,647.2 g/mol versus roughly 3,368 g/mol for the non-DAC modified GRF (1-29) form. Concentration in mg/mL is unaffected, but molar concentration differs by about 8%.

Which molecular weight does the matrix on this page use?
The DAC form, 3,647.2 g/mol, corresponding to PubChem CID 91971820. For the non-DAC variant multiply the nmol/mL column by approximately 1.08.

Does CJC-1295 need an acidified diluent?
No. It dissolves readily in plain bacteriostatic or sterile water and generally stays clear without gelling or clumping, so no acetic acid or other co-solvent is required.

Why should the vial not be shaken?
Shaking foams the solution. Foam maximises the air-liquid interface, which is where peptide chains unfold and aggregate. Gentle swirling or rolling dissolves the cake without generating foam.

How is the nmol/mL figure calculated?
Divide mg/mL by the molecular weight in g/mol and multiply by 1,000,000. At 2.50 mg/mL with the DAC molecular weight: (2.50 / 3,647.2) x 1,000,000 = 686 nmol/mL.

All values here are physical-chemistry reference data and fluid-mixing arithmetic for laboratory and research use only. Not dosing, medical, or therapeutic guidance; not intended for human or animal use. Products are sold for research, educational, and demonstration use only.

For research and educational use only. Preppin Peppers sells laboratory hardware and materials (reconstitution pens, cartridges, and bacteriostatic water), not peptides or anything for consumption. All content here, including the calculators, is educational and is not medical, veterinary, dosing, or compounding advice. It has not been evaluated by the FDA and is not intended to diagnose, treat, cure, or prevent any condition, or for human or animal use. You are responsible for complying with your local laws, and use is at your own risk.

Peptide Reconstitution Calculator

Enter your vial and the bacteriostatic (or sterile) water you added, then see exactly how many units to draw. Toggle mg or mcg, and hover any ? for help.

Powder in vial (mg)?The milligrams of peptide in your vial, as printed on its label. Bacteriostatic water (ml)?How much bacteriostatic water you mix into the vial. Target amount?The amount you want in a single draw. Toggle between mg and mcg.

Concentration?How concentrated the mixed solution is: milligrams of peptide per millilitre.5.0 mg/ml

Volume to draw?The millilitres you would draw to get your target amount.0.05 ml

Draw on a U-100 scale?The same volume in units on a standard U-100 syringe or pen. 1 unit = 0.01 ml.5 units

Per unit?How much peptide one unit on a U-100 syringe delivers at this concentration.50 mcg

Draws per vial?How many target-size draws one vial holds, rounded down.10

1 unit on a U-100 syringe or pen = 0.01 ml. 1 mg = 1000 mcg. Illustrative fluid math for research reconstitution.

How to reconstitute your vial

Reconstitution is adding liquid, almost always bacteriostatic water, to a freeze-dried (lyophilized) peptide so it can be measured accurately.

Clean both stoppers. Wipe the bacteriostatic water vial and the peptide vial with an alcohol swab before puncturing either one.
Draw the water first. Pull the full amount of bacteriostatic water into the syringe before adding anything to the peptide vial.
Add the water slowly. Aim the stream down the inside wall of the vial instead of blasting the powder directly.
Swirl gently. Roll or swirl the vial until the powder dissolves fully. Never shake it hard.
Refrigerate after mixing. Keep the reconstituted vial cold and away from light unless the label says otherwise.

Get your target amount from a licensed provider. This calculator handles the arithmetic, not the protocol.

How the math works

The peptide dissolves evenly in the water you add, so the concentration is simply the milligrams in the vial divided by the millilitres of water. U-100 syringes are marked in units, and 100 units equal 1 ml. The three formulas this calculator uses:

Concentration (mg/ml) = vial mg ÷ water ml
Units to draw = (target mcg ÷ (vial mg × 1000)) × water ml × 100
Draws per vial = (vial mg × 1000) ÷ target mcg, rounded down

Example: a 5 mg vial reconstituted with 2 ml of bacteriostatic water is 2.5 mg/ml, or 25 mcg per unit. A 250 mcg target is 10 units on a U-100 syringe (0.10 ml), and the vial holds 20 draws.

Peptide Cycle Calculator & Supply Planner

Add a card per peptide with its amount, schedule, and cycle length, then export to your calendar. Hover any ? for help.

Research supply & scheduling math only. This peptide cycle calculator maps a research schedule and its resupply math — the vials and cartridges a planned run needs, reconstitution timing, and what is left over. It is not a dosing schedule, a protocol, or medical or veterinary advice. Obtain any target amounts and administration guidance from a licensed provider.

Imports into Google Calendar, Apple Calendar and Outlook.

Generated in your browser and never stored. For research planning and supply estimation only, not dosing guidance.

DIY Peptide Blend Calculator

Mixing in one cartridge? Combining peptides is a stability question, not just a volume one. Some stay stable together, others degrade faster, and any blend shortens the beyond-use window. If compatibility is unknown, reconstitute separately or keep short-dated blends cold. This tool handles the volumes once you have decided what can share a cartridge.

Combine peptides into one cartridge and see the draw for each. Hover any ? for help.

Cartridge size (ml)?The total volume of the cartridge or vial you are blending into. Standard pen cartridges are 3 ml. Bacteriostatic top-up?No top-up keeps each draw small: just the blended solution divided by the number of draws. Fill adds plain bacteriostatic water so the cartridge is exactly full — every draw is the same volume but bigger.

Batch size (draws per cartridge)?How big a batch to make: how many draws this cartridge holds. It sets the total amount of each peptide, the vials you need, and how long the batch lasts. Your per-draw amount does not change with it. Tap a suggestion to use a full vial, or type your own.

Draws needed for your cycle (optional)?Copy the “Entries this cycle” number from the planner above. The supply rows then show cartridges to make and what is left of each peptide over the whole cycle.

Solution in cartridge?The combined volume of the reconstituted solutions you draw into the cartridge.—

Top-up water?Plain bacteriostatic water added last when Fill cartridge is on. With no top-up this shows the spare room left in the cartridge.—

Each draw?The volume of one draw in U-100 units and millilitres. With no top-up it is the blended solution divided by draws; with Fill cartridge it is the cartridge size divided by draws.—

Each draw contains—

Assumes each peptide dissolves fully and mixes evenly. Shelf life varies by peptide and handling; research planning math only, not dosing, compounding, or storage guidance. Confirm your protocol and storage with a licensed provider.

Research-supply interest list