How to use (3 steps)
- Select an example or enter vector length (bp) and insert length (bp).
- Enter the target molar ratio (e.g., 1:3) and vector mass (ng).
- The required insert mass (ng) and volume (µL) are shown (if concentration is provided).
This is a quantity calculator. Optimal ratios depend on end type and conditions; follow your protocol.
Inputs (vector/insert)
Results
Insert mass (ng)
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Insert volume (µL)
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Vector volume (µL)
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Total DNA mass (ng)
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Total DNA volume (µL)
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| DNA | Length (bp) | Mass (ng) | Concentration (ng/µL) | Volume (µL) | pmol (guide) |
|---|
The share URL can restore your inputs (fixed English keys).
This tool calculates amounts only. It does not guarantee success.
How it’s calculated
- As a dsDNA approximation, pmol = (mass_ng × 1000) / (bp × 660).
- Compute vector pmol from vector mass and length.
- Insert target pmol = vector pmol × target ratio, then convert back to mass (ng).
- If concentration is known, volume = mass / concentration.
Values are guides. Follow your protocol for final conditions.
FAQ
Why use molar ratios?
Fragments of different lengths have different molecule counts at the same mass. Molar ratios keep molecule counts consistent.
What ratios are commonly used?
Vector:insert ratios like 1:3 or 1:5 are common starting points. Optimal ratios depend on ends and conditions.
Which vector length should I use?
Use the actual length of the linearized vector fragment used for ligation, often the full plasmid length.
I do not know the insert concentration.
You can still calculate required mass (ng). Volume (µL) is shown only when concentration is provided.
My volumes are extremely small (e.g., 0.1 µL).
Very small volumes are error-prone. Consider intermediate dilution or adjust vector mass and reaction volume.
Will these amounts guarantee success?
No. This tool calculates amounts only. Success depends on end type, reaction conditions, and DNA quality.