What is Library Concentration Calculator?

NGS library concentration converter — Convert dsDNA library between mass (ng/µL) and molarity (nM) for sequencer loading. Formula: nM = (ng/µL × 10⁶) / (660 × avg fragment length). 660 g/mol/bp is the average dsDNA base-pair MW.

When should I use Library Concentration Calculator?

(1) Calculate Illumina sequencer loading concentration (e.g., NovaSeq 1.5 nM, MiSeq 10–20 pM) (2) Determine equimolar pooling volumes for multiplexed libraries (3) Library prep QC — expected vs measured yield (4) Long-read (Nanopore/PacBio) library loading conversion

Can you show me an example of Library Concentration Calculator?

Example 1) RNA-seq library, Qubit 15 ng/µL, TapeStation peak 350 bp → nM = (15 × 10⁶) / (660 × 350) = 64.9 nM → For 4 nM denatured loading, dilute ~16.2× Example 2) Pooling — Library A 20 nM × 50 µL + Library B 10 nM × ? → For equimolar pooling, use 100 µL of B

Library Concentration Calculator

NGS 라이브러리 농도 변환 (ng/µL ↔ nM)

nM = (ng/µL × 10⁶) / (660 × avg fragment length)

LIBRARY CONCENTRATION

AVERAGE FRAGMENT LENGTH (bp)

Typical: Illumina ~300bp, Ion Torrent ~200bp

MOLAR CONCENTRATION

0.00nM

REFERENCE

• Illumina loading: typically 1.5–2.0 nM (denatured)
• Standard pooling: 4 nM recommended
• dsDNA constant: 660 g/mol/bp

도구 가이드

정의

NGS Library 농도 변환기 — Qubit/TapeStation으로 측정한 dsDNA library를 mass(ng/µL) ↔ molarity(nM)로 변환합니다. 공식: nM = (ng/µL × 10⁶) / (660 × avg fragment length). 660 g/mol/bp은 dsDNA의 평균 base pair 분자량.

목적

(1) Illumina sequencer loading 농도 산출 (예: NovaSeq 1.5 nM, MiSeq 10~20 pM) (2) Multiplexing 시 multiple library equimolar pooling 양 결정 (3) Library prep QC — 예상 yield vs 실측 비교 (4) Long-read (Nanopore/PacBio) library loading 양 환산

사용법

① Library 농도 입력 (ng/µL — Qubit 측정값) ② Average fragment length (bp — TapeStation/Bioanalyzer peak size) ③ 변환 방향 선택 (ng/µL → nM 또는 nM → ng/µL) ④ 결과 자동 출력 주의: Adapter 포함 길이(예: 350 bp insert + 120 bp adapter = 470 bp)를 사용해야 정확. qPCR-based KAPA library quant이 더 정확하지만 본 도구는 빠른 환산용.

예시

예 1) RNA-seq library, Qubit 15 ng/µL, TapeStation peak 350 bp → nM = (15 × 10⁶) / (660 × 350) = 64.9 nM → 4 nM denatured loading 만들 때 64.9/4 = ~16.2배 희석 예 2) Pooling — Library A 20 nM 50 µL + Library B 10 nM ? → Equimolar pooling: B 100 µL 사용해 동일 mole 맞춤