GEVIBench › All sensors › VSFP3.1
VSFP3.1
Third-generation Ci-VSP voltage sensor using a single Cerulean fluorescent protein, derived from VSFP2 by removing the FRET acceptor, achieving the fastest response kinetics reported among fluorescent protein-based voltage indicators at the time.
- Category: VSD-FRET GEVI
- Published: 2009-06-10 — Front. Mol. Neurosci. 2009
- Derived from: VSFP2.1
- Response polarity: negative-going (fluorescence decreases on depolarization)
- Spectrum: excitation peak 435 nm, emission peak 477 nm (VSFP3.1)
- Plasmid: Addgene #18951
- Tags: Ci-VSP, Cerulean, Single FP, Fast kinetics
Headline values (as shown in the GEVIBench table)
| Metric | Value | Definition |
|---|---|---|
| Brightness (B/B_EGFP) | 0.79× EGFP | Molecular brightness relative to EGFP (extinction coefficient × quantum yield, or a measured ratio). Sensors not measured against EGFP directly are placed through a chain of pairwise brightness comparisons, combined by geometric mean. |
| Kinetics τ_on / τ_off (ms) | 25 / NaN ms | Activation / decay time constants in ms (amplitude-weighted mean τ for multi-exponential fits). The value shown averages the measurements made at physiological temperature (≥33 °C); if there are none, it is the measurement closest to 33 °C. |
| ΔF/F per 100 mV | -1.3% | Steady-state fluorescence change for a 100 mV depolarization step (−70 → +30 mV); the sign gives the polarity. The table shows the first listed measurement; the median across measurements (one-photon preferred) is used for sorting. |
| ΔF/F per mV | 0.02% (estimated from the F–V curve) | Subthreshold sensitivity: fluorescence change per mV near rest (−90 to −50 mV). Where no value is reported directly, it is estimated from the F–V curve. |
| ΔF/F per AP | 0.075% | Fluorescence change per single action potential in neurons. The table shows the first listed measurement; the median across measurements (one-photon preferred) is used for sorting. |
| AP width (FWHM, ms) | — | Full width at half maximum of the optical spike waveform. |
| Photostability t75% @ 100 mW/mm² | — | Time for fluorescence to fall to 75% of its initial value under one-photon illumination, linearly dose-scaled to 100 mW/mm² (t50% is used where the 75% crossing falls inside a fast initial transient). Two-photon curves are not dose-scaled and are excluded. |
| Papers using it (N_used) | 5 | Number of published research papers, tracked by GEVIBench, that used the sensor for an experiment (a popularity / track-record measure). |
Measurements and sources
Kinetics
- τ_on 1.3 ms, τ_off — ms at 25°C — Lundby 2008, Fig. 3C
- τ_on 25.3 ms, τ_off — ms at 35°C — Perron 2009, Table 1
ΔF/F per 100 mV
- -1.3%, 1P — Perron 2009, Table 1
ΔF/F per action potential
- 0.075%, 1P — Akemann 2009, Fig. 9 C2
Brightness comparisons
- 0.79× the brightness of EGFP — doi:Estimated from Cerulean EC=43000, QY=0.62 vs EGFP EC=56000, QY=0.60, FPbase
Fluorescence–voltage (F–V) curve
ΔF/F (%) at each membrane potential, normalized to 0 at −70 mV: -110 mV: 0.5%; -90 mV: 0.3%; -70 mV: 0%; -50 mV: -0.5%; -30 mV: -0.9%; -10 mV: -1.2%; 10 mV: -1.3%; 30 mV: -1.3%; 50 mV: -1.4%; 70 mV: -1.4%; 90 mV: -1.4% — Lundby 2008, Fig. S3a
Research papers using VSFP3.1 (5)
- Second and third generation voltage-sensitive fluorescent proteins for monitoring membrane potential — Perron A, Mutoh H, Akemann W, Ghimire Gautam S, Dimitrov D, Iwamoto Y, Knöpfel T, Frontiers in Molecular Neuroscience 2009 (PC12 cells, hippocampal neurons, in vitro)
- Engineering of a genetically encodable fluorescent voltage sensor exploiting fast Ci-VSP voltage-sensing movements — Lundby A, Mutoh H, Dimitrov D, Akemann W, Knöpfel T, PLoS ONE 2008 (PC12 cells, in vitro voltage clamp)
- Red-shifted voltage sensitive fluorescent proteins — Perron A, Mutoh H, Launey T, Knöpfel T, Chemistry & Biology 2009 (PC12 cells, hippocampal neurons, in vitro)
- Effect of voltage sensitive fluorescent proteins on neuronal excitability — Akemann W, Lundby A, Mutoh H, Knöpfel T, Biophysical Journal 2009 (PC12 cells, computational model, in vitro)
- Membrane 'potential-omics': toward voltage imaging at the cell population level in roots of living plants — Matzke AJ, Matzke M, Frontiers in Plant Science 2013 (Arabidopsis thaliana roots, in vivo (expressed the VSFP3.1_TagRFP color variant, plus VSFP2.3 and VSFP2.4; not the Cerulean VSFP3.1))
Data and citation
- llms.txt — summary for language models
- llms-full.txt — every sensor in full (Markdown)
- gevis.json — all values and measurements with sources (JSON)
- gevis.csv — one row per sensor (CSV)
Cite GEVIBench as: Adam E. Cohen and Daozheng Gong (2026). Voltage imaging: A practical guide. Neuron. https://doi.org/10.1016/j.neuron.2026.08.002
Generated from the GEVIBench database on 2026-10-12.