Quick answer
How do you reconstitute a CJC-1295 + Ipamorelin blend? Let the sealed vial reach room temperature, swab the stopper, and run bacteriostatic water slowly down the inside glass wall. Swirl gently until the solution is clear; never shake. Adding 2 mL to a 5 mg / 5 mg vial gives 2.5 mg/mL of each peptide (5 mg/mL combined), and 2 mL in a 10 mg / 10 mg vial gives 5 mg/mL of each. Store the solution at 2–8 °C, protected from light, and plan to use it within about 28 days. Our reconstitution calculator does the math for any other volume.
A co-lyophilized blend behaves like a single vial on the bench, but its arithmetic is slightly different from a one-compound peptide: every draw carries two analytes at once. This guide covers the full bench workflow for the CJC-1295 (No DAC) + Ipamorelin blend, the concentration math for both common vial sizes, how those concentrations translate to markings on a U-100 laboratory syringe, and how to store the vial before and after water is added. It deliberately covers reconstitution and concentration only. For laboratory research use only; not for human consumption.
Key facts at a glance
| Parameter | CJC-1295 (No DAC) | Ipamorelin |
|---|---|---|
| Also known as | Modified GRF (1-29), tetrasubstituted GRF (1-29) | NNC 26-0161 |
| Length | 29 amino acids | 5 residues (pentapeptide amide) |
| Approximate molecular weight | 3,367.9 g/mol | 711.9 g/mol |
| Receptor studied | GHRH receptor | Ghrelin / GHS-R1a receptor |
| Supplied form | Co-lyophilized white cake or powder in a single sealed vial | |
| Common blend sizes | 5 mg / 5 mg (10 mg total) and 10 mg / 10 mg (20 mg total) | |
| Typical diluent | Bacteriostatic water (sterile water with 0.9% benzyl alcohol) | |
Why blend math differs from a single-compound vial
With a single-peptide vial there is one number to track: milligrams of peptide divided by milliliters of diluent. In a blend, both peptides dissolve into the same liquid, so one added volume sets two concentrations simultaneously. Three consequences follow, and they are the source of most bench errors with this product.
- The label describes two masses, not one. A vial marked 5 mg / 5 mg holds 10 mg of total peptide. If you divide 10 mg by the diluent volume you get the combined concentration, which is twice the concentration of either individual component. Decide up front which figure your lab notebook records, and record both if there is any doubt.
- The ratio is fixed at manufacture. Because the two peptides were freeze-dried together, no amount of water changes their ratio. In a 1:1 blend the mg/mL figures for CJC-1295 and Ipamorelin are always identical. You can dilute both, but you cannot adjust one independently. A study design that needs unequal amounts needs separate vials of CJC-1295 (No DAC) and Ipamorelin.
- Equal mass is not equal moles. Ipamorelin is roughly one-fifth the molecular weight of CJC-1295 (No DAC). Equal milligrams therefore means about 4.7 times as many Ipamorelin molecules as CJC-1295 molecules. For receptor-binding or cell-based work reported in molar units, convert each component separately (see the molarity table below).
What you need on the bench
- The sealed blend vial, plus its batch certificate of analysis from our COA library
- Bacteriostatic water (0.9% benzyl alcohol), within its expiry and within 28 days of first puncture
- A sterile 1 mL or 3 mL syringe for transferring diluent, and U-100 syringes or calibrated micropipettes for measuring aliquots
- 70% isopropyl alcohol swabs, nitrile gloves, and a clean, low-traffic work surface or laminar-flow hood
- A label or marker to record the reconstitution date and the concentration on the vial
Step-by-step reconstitution
1. Equilibrate the vial
Take the vial out of cold storage and leave it sealed for 15–30 minutes. Opening or piercing a cold vial invites condensation, and moisture is the main enemy of a freeze-dried cake. Bring the bacteriostatic water to room temperature as well.
2. Inspect and verify
Confirm the label matches the batch number on the COA. The cake should be white to off-white and intact or lightly fractured. A collapsed, glassy or discolored cake, or a loose crimp seal, is a reason to quarantine the vial rather than proceed.
3. Decide the volume before you draw
Pick the diluent volume from the tables below (or the calculator) and write the resulting concentration down first. Deciding at the bench with a loaded syringe in hand is how volumes get misread.
4. Disinfect both stoppers
Remove the flip caps, wipe the stopper of the peptide vial and the stopper of the diluent vial with separate alcohol swabs, and let them air dry for about 30 seconds. Wet alcohol carried in on a needle is a contaminant.
5. Add the water slowly, down the glass
Draw the planned volume of bacteriostatic water. Pierce the peptide vial at a slight angle and aim the stream at the inner wall so the liquid runs down the glass rather than striking the cake. Many vials are sealed under partial vacuum and will pull the water in; hold the plunger back and let it enter gradually.
6. Swirl, do not shake
Roll or gently swirl the vial for 20–60 seconds, then let it stand. Vigorous shaking or vortexing introduces air–liquid interfaces and shear, both of which promote aggregation in peptide solutions. If particles remain after a few minutes, rest the vial in the refrigerator for 15–30 minutes and swirl again.
7. Confirm clarity, label and refrigerate
The finished solution should be clear and colorless with no visible particles. Label the vial with date, diluent, volume and concentration of each component, then place it at 2–8 °C.
Concentration table: 5 mg / 5 mg vial
The governing formula is simple: concentration (mg/mL) = peptide mass (mg) ÷ diluent volume (mL). Applied to each component of a 5 mg / 5 mg vial, it gives the values below. The right-hand columns show the mass contained in 10 units (0.1 mL) on a U-100 syringe scale.
| Diluent added | CJC-1295 (mg/mL) | Ipamorelin (mg/mL) | Total peptide (mg/mL) | CJC-1295 per 10 units | Ipamorelin per 10 units |
|---|---|---|---|---|---|
| 1 mL | 5 | 5 | 10 | 500 mcg | 500 mcg |
| 2 mL | 2.5 | 2.5 | 5 | 250 mcg | 250 mcg |
| 2.5 mL | 2 | 2 | 4 | 200 mcg | 200 mcg |
| 3 mL | 1.67 | 1.67 | 3.33 | 167 mcg | 167 mcg |
| 5 mL | 1 | 1 | 2 | 100 mcg | 100 mcg |
Concentration table: 10 mg / 10 mg vial
The larger vial holds twice the mass, so the same water volume produces twice the concentration. To match the concentration of a 5 mg / 5 mg vial, double the diluent.
| Diluent added | CJC-1295 (mg/mL) | Ipamorelin (mg/mL) | Total peptide (mg/mL) | CJC-1295 per 10 units | Ipamorelin per 10 units |
|---|---|---|---|---|---|
| 1 mL | 10 | 10 | 20 | 1,000 mcg | 1,000 mcg |
| 2 mL | 5 | 5 | 10 | 500 mcg | 500 mcg |
| 3 mL | 3.33 | 3.33 | 6.67 | 333 mcg | 333 mcg |
| 4 mL | 2.5 | 2.5 | 5 | 250 mcg | 250 mcg |
| 5 mL | 2 | 2 | 4 | 200 mcg | 200 mcg |
Choosing a bacteriostatic water volume
No single volume is "correct". The peptide mass in the vial is fixed; the water you add only determines how concentrated the solution is. The choice is a trade-off between measurement resolution and practical convenience.
| If your priority is… | Lean toward | Why |
|---|---|---|
| Round, easy-to-check numbers | 2 mL (5/5 vial) or 4 mL (10/10 vial) | Gives 2.5 mg/mL of each peptide, so each unit mark equals 25 mcg of each component |
| Fine measurement resolution for small aliquots | More diluent (3–5 mL) | A lower concentration means a larger, easier-to-read volume for the same mass |
| Small aliquot volumes | Less diluent (1–2 mL) | Higher concentration packs more mass into each 0.01 mL |
| Staying inside the vial's capacity | Check vial size first | A 3 mL vial physically cannot take 5 mL; leave headspace for swirling |
One practical note: very concentrated solutions (1 mL in a 10 mg / 10 mg vial is 20 mg/mL of total peptide) take longer to clear and magnify any measurement error, because each unit mark represents a large mass. Most labs find the 2–4 mL range the easiest to work with.
Syringe-unit reference for a U-100 scale
A U-100 syringe is graduated in "units", where 100 units equals exactly 1 mL. Each unit is therefore 0.01 mL (10 microliters). The unit is a volume marking on the barrel, not a measure of peptide mass, so the mass per unit depends entirely on the concentration you created.
| Units on U-100 scale | Volume | Each peptide at 2.5 mg/mL | Each peptide at 5 mg/mL |
|---|---|---|---|
| 1 unit | 0.01 mL | 25 mcg | 50 mcg |
| 2 units | 0.02 mL | 50 mcg | 100 mcg |
| 4 units | 0.04 mL | 100 mcg | 200 mcg |
| 10 units | 0.10 mL | 250 mcg | 500 mcg |
| 20 units | 0.20 mL | 500 mcg | 1,000 mcg |
| 50 units | 0.50 mL | 1,250 mcg | 2,500 mcg |
To find the units needed for any target aliquot mass: units = (target mass in mcg ÷ concentration in mcg/mL) × 100. Because the blend is 1:1, a draw that contains a given mass of CJC-1295 contains the same mass of Ipamorelin. For quantitative analytical work, a calibrated micropipette is more accurate than a syringe barrel; the unit scale is a convenience for routine volumetric transfers.
Molarity for in vitro work
| Mass concentration (each) | CJC-1295 (No DAC), ~3,367.9 g/mol | Ipamorelin, ~711.9 g/mol |
|---|---|---|
| 1 mg/mL | ≈ 297 µM | ≈ 1,405 µM |
| 2.5 mg/mL | ≈ 742 µM | ≈ 3,512 µM |
| 5 mg/mL | ≈ 1,485 µM | ≈ 7,023 µM |
These figures assume the labeled mass is 100% peptide. For exact molar work, correct for the net peptide content and purity reported on the batch COA; our guide to CJC-1295 + Ipamorelin purity testing explains how to read those values.
Common reconstitution mistakes
| Mistake | What goes wrong | How to avoid it |
|---|---|---|
| Dividing total mass (10 mg) by volume and recording it as the per-peptide figure | Every downstream calculation is off by a factor of two | Label the vial with the concentration of each component separately |
| Squirting diluent directly onto the cake | Foaming and local shear; slower, incomplete dissolution | Run the stream down the glass wall |
| Shaking to speed things up | Aggregation and adsorption at air–liquid interfaces | Swirl, rest, swirl again |
| Piercing a cold vial | Condensation introduces uncontrolled moisture | Equilibrate the sealed vial for 15–30 minutes |
| Mixing up mg and mcg | 1,000-fold errors | Convert everything to mcg/mL before calculating units |
| Using plain sterile water for a vial that will be re-entered | No preservative to suppress microbial growth between punctures | Use bacteriostatic water for multi-use vials |
| Ignoring dead volume | The last 0.05–0.1 mL is often unrecoverable, so the vial yields fewer aliquots than calculated | Plan on roughly 90–95% recoverable volume |
Tracking a multi-use vial across its working window
Once reconstituted, the vial becomes a multi-use container that will be punctured repeatedly. Good practice is the same as for any shared stock solution:
- Keep a draw log. Record date, volume removed and remaining volume. A 2 mL fill yields 200 units on paper; a log tells you when the real remainder is getting close to the dead volume.
- Swab before every entry. Each puncture is a contamination opportunity. Benzyl alcohol is bacteriostatic, meaning it inhibits growth; it does not sterilize a contaminated solution.
- Use a fresh sterile needle each time and vary the puncture site slightly to limit stopper coring.
- Minimize time out of the refrigerator. Remove the vial, draw, and return it. Cumulative warm time adds up over a month.
- Re-inspect before each use. Cloudiness, visible particles, color change or a film on the glass means the vial should be discarded and documented.
Storage before and after reconstitution
| State | Temperature | Typical working window | Notes |
|---|---|---|---|
| Lyophilized, long-term | −20 °C or colder | 12–24+ months | Sealed, dark, dry; avoid frost-free freezer cycling |
| Lyophilized, short-term | 2–8 °C | Weeks to a few months | Keep in original box away from the door |
| Lyophilized, in transit | Ambient | Days | Freeze-dried peptides tolerate short ambient shipping; refrigerate on arrival |
| Reconstituted in bacteriostatic water | 2–8 °C | Up to about 28 days | Upright, protected from light; do not freeze the working vial repeatedly |
| Reconstituted in plain sterile water | 2–8 °C | Single session; discard remainder | No preservative |
| Reconstituted, single-use aliquots | −20 °C | Several weeks to months | Low-bind tubes; one thaw only |
The 28-day figure is not a measured stability limit for this particular blend. It reflects the convention applied to preserved multi-use containers, which traces to antimicrobial effectiveness testing under USP <51> and the beyond-use framework in USP <797>. Chemical stability of the peptides themselves is governed by different mechanisms. CJC-1295 (No DAC) was engineered with four substitutions relative to native GRF (1-29) specifically to resist enzymatic cleavage and the asparagine and methionine degradation that limit the parent sequence, and Ipamorelin is a compact pentapeptide with no methionine or cysteine. Neither feature makes the solution indefinitely stable: hydrolysis, deamidation and surface adsorption continue slowly in water, and all of them accelerate with temperature. If your protocol depends on precise potency late in the window, verify it analytically rather than assuming it.
The co-lyophilized format does not meaningfully shorten or lengthen the working window relative to either peptide alone. In practice the microbiological limit of the preserved diluent, not peptide chemistry, sets the conservative end date. For a deeper look at cold-chain practice, see storing research peptides and does bacteriostatic water expire?
Related research
- CJC-1295 (No DAC) + Ipamorelin blend – product specifications and batch documentation
- CJC-1295 + Ipamorelin research overview
- Mechanism of action: GHRH and ghrelin receptor signaling
- How to mix peptides with bacteriostatic water
- Bacteriostatic water explained
- CJC-1295 with DAC: reconstitution and storage
References
- United States Pharmacopeia. General Chapter <797> Pharmaceutical Compounding—Sterile Preparations. USP–NF.
- United States Pharmacopeia. General Chapter <51> Antimicrobial Effectiveness Testing. USP–NF.
- Jetté L, Léger R, Thibaudeau K, et al. Human growth hormone-releasing factor (hGRF)1-29-albumin bioconjugates activate the GRF receptor on the anterior pituitary in rats: identification of CJC-1295 as a long-lasting GRF analog. Endocrinology. 2005;146(7):3052-3058.
- Raun K, Hansen BS, Johansen NL, et al. Ipamorelin, the first selective growth hormone secretagogue. Eur J Endocrinol. 1998;139(5):552-561.
- Manning MC, Chou DK, Murphy BM, Payne RW, Katayama DS. Stability of protein pharmaceuticals: an update. Pharm Res. 2010;27(4):544-575.
- Wang W. Lyophilization and development of solid protein pharmaceuticals. Int J Pharm. 2000;203(1-2):1-60.
- Meyer BK, Ni A, Hu B, Shi L. Antimicrobial preservative use in parenteral products: past and present. J Pharm Sci. 2007;96(12):3155-3167.
Frequently Asked Questions
How much bacteriostatic water should I add to a 5 mg / 5 mg CJC-1295 + Ipamorelin vial?
Any volume the vial can hold will work; the choice only sets the concentration. Adding 2 mL is the most common because it gives 2.5 mg/mL of each peptide, which is 25 mcg of each per unit mark on a U-100 syringe. Adding 1 mL gives 5 mg/mL of each and 5 mL gives 1 mg/mL of each.
How much bacteriostatic water goes into a 10 mg / 10 mg vial?
Adding 2 mL gives 5 mg/mL of each peptide, and 4 mL gives 2.5 mg/mL of each, matching a 5 mg / 5 mg vial reconstituted with 2 mL. Check the vial's physical capacity before choosing a larger volume.
Do the two peptides need to be reconstituted separately?
No. In a co-lyophilized blend both peptides are in the same cake and dissolve together in one step. Separate reconstitution only applies when you purchase CJC-1295 (No DAC) and Ipamorelin as individual vials.
Will the CJC-1295 and Ipamorelin concentrations always be equal?
In a 1:1 blend, yes in mass terms. The ratio is fixed when the vial is filled, so both components always share the same mg/mL value regardless of how much water is added. Their molar concentrations differ because Ipamorelin has a much lower molecular weight.
How long is the reconstituted blend good for in the refrigerator?
The conventional working window for a peptide reconstituted in bacteriostatic water and kept at 2–8 °C is up to about 28 days, which mirrors the standard applied to preserved multi-use containers. It is a conservative handling convention, not a measured stability claim for a specific batch.
Can I use sterile water instead of bacteriostatic water?
Sterile water dissolves the blend equally well, but it contains no preservative. It is appropriate when the whole vial will be used in a single session or immediately divided into frozen single-use aliquots. For a vial that will be punctured repeatedly over days or weeks, bacteriostatic water is the standard choice.
What happens if I add too much or too little water by mistake?
The peptide is not harmed; only the concentration changes. Record the volume you actually added and recalculate using mass divided by volume. If you added too little, you can add more to reach the planned volume. If you added too much, simply work with the lower concentration.
Why is my solution cloudy after adding water?
Brief haziness or bubbles right after addition usually clear with gentle swirling and a few minutes of rest. Persistent cloudiness, visible particles or gel-like strands suggest aggregation or contamination, and the vial should not be used for quantitative work.
Can I freeze the reconstituted blend?
Freezing is reasonable only for single-use aliquots in low-bind tubes that will be thawed once. Repeatedly freezing and thawing the working vial stresses the peptides and can crack glass. For routine multi-use handling, refrigeration at 2–8 °C is the norm.
How many units on a U-100 syringe equal 1 mL?
One hundred units equals 1 mL, so each unit mark is 0.01 mL. The peptide mass in each unit depends on the concentration: at 2.5 mg/mL of each peptide, one unit holds 25 mcg of CJC-1295 and 25 mcg of Ipamorelin.
Does the blend need different equipment from a single-peptide vial?
No. The same sterile syringes, alcohol swabs and bacteriostatic water are used. The only difference is in record-keeping: each measured volume contains two peptides, and the label should state the concentration of both.