mg to pmol Converter
To convert mg to pmol, divide the value in milligrams by the molecular weight (g/mol), then multiply by 1,000,000,000.
How to Convert mg to pmol
This mg to pmol converter changes milligrams into picomoles. Enter the mass in mg and the molecular weight.
mg ÷ MW gives millimoles. Multiply by 109 to get picomoles: pmol = mg ÷ MW × 109.
For example, 1 mg of caffeine (MW 194.194 g/mol) ≈ 5,149,000 pmol.
pmol = mg ÷ MW × 1,000,000,000Divide the mass in mg by the molecular weight (g/mol), then multiply by 1,000,000,000 (10⁹) to get picomoles.Conversion Formula
The formula to convert mg to pmol is:
Where:
- mg = mass in milligrams (10⁻³ g)
- pmol = amount in picomoles (10⁻¹² mol)
- MW = molecular weight (molar mass) in g/mol
Conversion Table
Common mg to pmol conversions are shown below. The last column uses caffeine (MW 194.194 g/mol) as an example.
| mg | pmol (formula) | pmol for caffeine |
|---|---|---|
| 0.01 | 10,000,000 ÷ MW | 51,494.89686 |
| 0.1 | 100,000,000 ÷ MW | 514,948.9686 |
| 0.33 | 330,000,000 ÷ MW | 1,699,331.596 |
| 0.5 | 500,000,000 ÷ MW | 2,574,744.843 |
| 1 | 1,000,000,000 ÷ MW | 5,149,489.686 |
| 2.5 | 2,500,000,000 ÷ MW | 12,873,724.21 |
| 5 | 5,000,000,000 ÷ MW | 25,747,448.43 |
| 10 | 10,000,000,000 ÷ MW | 51,494,896.86 |
| 33 | 33,000,000,000 ÷ MW | 169,933,159.6 |
| 50 | 50,000,000,000 ÷ MW | 257,474,484.3 |
| 100 | 100,000,000,000 ÷ MW | 514,948,968.6 |
| 250 | 250,000,000,000 ÷ MW | 1,287,372,421 |
| 500 | 500,000,000,000 ÷ MW | 2,574,744,843 |
| 1,000 | 1 × 10¹² ÷ MW | 5,149,489,686 |
Worked Examples
Here are some common examples of mg to pmol conversion, using caffeine (MW 194.194 g/mol):
- 5,149,489.686 pmol = 1 mg
- 25,747,448.43 pmol = 5 mg
- 169,933,159.6 pmol = 33 mg
- 514,948,968.6 pmol = 100 mg
Unit Definitions
What is a milligram (mg)?
A milligram (mg) is a unit of mass equal to 10⁻³ gram.
The prefix milli- (m) means 10⁻³, or one thousandth. So 1 mg = 0.001 g.
What is a picomole (pmol)?
A picomole (pmol) is a unit of amount of substance equal to 10⁻¹² mole.
The prefix pico- (p) means 10⁻¹², or one trillionth. So 1 pmol = 0.000000000001 mol.
Why Is Molecular Weight Needed?
Moles count particles. Grams measure mass. One particle of each substance has its own mass, so the link between them is the molecular weight (MW), also called molar mass.
MW tells you how many grams one mole of a substance weighs. For example, one mole of water weighs about 18.015 g, while one mole of glucose weighs about 180.16 g.
Therefore, to convert mg to pmol, you divide by MW, then multiply by 1,000,000,000. The extra step (× 1,000,000,000) only adjusts for the different sizes of the two units.
Uses and Importance of mg and pmol
This conversion shows how many picomole-scale uses a weighed milligram can supply.
Stock planning
One milligram of a small molecule holds millions of picomoles, enough for a very large number of sensitive tests.
Calibration curves
Standards weighed in mg are diluted to pmol levels for sensitive instruments.
Comparing units
Converting helps compare a supplier's mg pack size with an assay kit's pmol needs.
Frequently Asked Questions (FAQ)
How many pmol are in 1 mg of caffeine?
About 5,149,000 pmol.
Why multiply by 109?
mg ÷ MW gives mmol, and 1 mmol = 109 pmol.
How many 50 pmol injections can 1 mg of caffeine supply?
About 103,000 injections, ignoring losses.
Is this result shown in scientific notation?
If the value reaches one trillion or more, yes. For 1 mg of most small molecules the answer stays in the millions.
What changes for a heavier molecule?
A heavier molecule gives fewer picomoles per milligram, because each molecule weighs more.
Other Related Tools
Accuracy and Scope
The result depends on the molecular weight you enter.
Example values are rounded to four significant figures.
Sources