Guides · Research, learning and handling

Peptology Guides

Plain-language guides to measuring, reconstitution, storage and reading a laboratory certificate, written so you can get the arithmetic and the handling right before a vial is opened. For research use only: these guides explain handling and measurement, not treatment.

Start here

The basics every order depends on

Tool

Calculators

Reconstitution with the water to draw and the syringe reading, an order calculator for how many vials, and a unit converter.

Open the calculators → Tool

Protocol planner

Schedule, step-up phases and cycles, a calendar, a daily checklist and your vials, saved on your device.

Open the planner → Guide

How to read an insulin syringe

Units and mL, 1 and 2-unit lines, half-unit readings, needle length and gauge.

Read the guide → Guide

How to read a COA

Identity, purity, quantity, endotoxin and heavy metals, and how to verify a lot.

Read it → Guide

Storage and cold chain

Before and after reconstitution, and what a warm parcel means for a peptide.

Read it →

How to read a U-100 insulin syringe

Units, sizes, lines and needles

An insulin syringe is a measuring tool. On a U-100 syringe, 100 units always equal 1 mL, so 1 unit is 0.01 mL of whatever is in the barrel. The units are a volume, not a weight: how much compound sits in a unit depends on how much water you added (the calculator works it out).

Three sizes, one scale

0.25 mL · small amounts

25 units

Lines every 1 unit, numbered every 5.

0.5 mL · moderate amounts

50 units

Lines every 1 unit, numbered every 5.

1 mL · larger amounts

100 units

Lines every 2 units, numbered every 10.

mL to units

Volume	Units (U-100)
1 mL	100 units
0.5 mL	50 units
0.3 mL	30 units
0.25 mL	25 units
0.1 mL	10 units
0.01 mL	1 unit

What one line is worth

On a syringe with 1-unit lines, every line on the barrel is 1 unit. On a syringe with 2-unit lines (most 1 mL syringes), every line is 2 units, so an odd number such as 15 sits halfway between the 14 and 16 lines.

Count from the last numbered line: on a 0.5 mL syringe, three lines past 20 is 23 units. On a 1 mL syringe, three lines past 20 is 26 units.

Read it yourself

A · 0.25 mL syringe

B · 0.5 mL syringe

C · 1 mL syringe

Read at the front edge of the dark rubber stopper (the edge nearest the needle, marked gold in these drawings), not at its back edge and not at the tip of its cone.

Same amount, two syringes

0.5 mL U-10035 units, 1-unit lines

1 mL U-10035 units, 2-unit lines

Why the smaller syringe reads finer

Both syringes hold exactly 35 units (0.35 mL). On the 0.5 mL barrel the 50 units are spread over the full length, so each unit has its own line. On the 1 mL barrel the same length carries 100 units, so lines are 2 units apart and 35 falls between two of them.

Rule of thumb: use the smallest syringe that holds the whole draw. It gives the widest spacing between lines and the most accurate reading.

Half-unit readings

0.3 mL · 30 units · half-unit lines

2.5 units, magnified

Some 0.3 mL syringes print a short line halfway between each unit. Here the stopper's front edge sits on the short line between 2 and 3: that is 2.5 units, or 0.025 mL.

If your syringe has no half lines, a reading of 2.5 has to be judged by eye, which is less accurate. Adding more water so the same amount lands on a whole unit is better; the calculator suggests a water volume that does that.

Needle length

Printed on the box as the second number, for example 31G x 8 mm.

Gauge (needle thickness)

The first number on the box. A higher gauge number means a thinner needle.

Outside diameters are nominal values, drawn to scale relative to each other.

How to read the syringe, in five steps

Identify the syringe

Check the size printed on the barrel or box: 0.25, 0.3, 0.5 or 1 mL, U-100. That tells you whether a line is 1 or 2 units.

Find your line

Locate the reading from the calculator. Count lines from the nearest number.

Hold it at eye level

Looking from above or below shifts the line you see. Keep the barrel level with your eye.

Line up the stopper

Draw until the front edge of the rubber stopper sits exactly on the line.

Check again

Tap out air bubbles, push the air back, and read the line a second time.

Quick tips

Smallest syringe that fits. Finer line spacing, better accuracy.
Units are volume. 10 units is always 0.1 mL; the amount of compound in it depends on the water you added.
Between lines? Change the water volume so the reading lands on a line. The calculator offers one.
Bubbles count. An air bubble in the barrel takes the place of liquid. Remove it before you read.
One syringe, one use. Needles blunt and are not sterile after use. Dispose of them in a sharps container.
Write it on the vial. Label the reconstituted vial with the date, the water added and the concentration.

Research use only. This guide explains how to measure a volume accurately; it is not an instruction to inject anything.

Reconstitution with bacteriostatic water

Freeze-dried powder to a measured solution

Work it out first

Decide the water volume with the calculator so your reading lands on a line you can hit.

Room temperature, clean stoppers

Let a cold vial reach room temperature. Wipe both rubber stoppers with an alcohol swab and let them dry.

Add the water slowly

Run the water down the inside wall of the vial, not straight onto the powder.

Swirl, don't shake

Roll or swirl gently until the solution is clear. Shaking can foam and damage peptides.

Label and store

Write the date and the concentration on the vial, then store it as the product sheet says (usually refrigerated, protected from light).

Understanding your vial volume

A freeze-dried vial often looks almost empty: the powder is a small cake or a thin film. The amount is set by weight, not by fill height, and the certificate reports the measured milligrams. Two vials of the same lot can look different and hold the same amount.

Why bacteriostatic water

Bacteriostatic water is sterile water with 0.9% benzyl alcohol, which slows bacterial growth when a vial is entered several times. Sterile water without a preservative is meant for single use.

Storage and cold chain

General handling; the product sheet wins

Before mixing

Freeze-dried peptides tolerate normal transit at room temperature for days.
For storage, keep them cold and dry as the product sheet states, away from light.
Leave the vial sealed until you need it.

After mixing

Keep a reconstituted vial refrigerated (2 to 8 °C), protected from light.
Avoid repeated freezing and thawing.
How long it keeps differs by compound: check the product sheet, and do not assume.

A warm parcel

Freeze-dried powder that arrived warm after normal transit is usually fine; put it in the fridge on arrival.
Liquids and pre-mixed products ship cold and should be refrigerated at once.
Unsure about a lot? Message us, or have it tested.

Research library and programs

Programs by goal, and plain summaries of the published research

Programs by goal

Start with the goal, not the molecule. Every program has two paths: a plain-language patient pathway and a deeper provider protocol. Flip the switch and each card updates.

Show me the

Energy & mitochondria