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Fast Fluorometer FL 3500-F

The Fast Fluorometer FL 3500-F has multiple novel features, first of all the time resolution of 1 µs, that enable combining PAM measurements with fast kinetic measurements of OJIP and of flash fluorescence induction.

The core of the instrument is the measuring optical head containing a standard cuvette for sample suspensions (10 x 10 mm base, up to 4 ml of internal volume). The measuring head is supplied with three sets of light-emitting diodes and a PIN diode detector with 500 kHz/16-bit AD converter. Gain and integration time of the converter are software controlled. The detector can measure Chl-fluorescence signal with time resolution up to 1 µs. The instrument has two input channels.

The Fluorometer is supplied with three, optionally four, sets of light-emitting diodes that generate:
  • Measuring flashes, typically 2-5 µs long. Standard color: red-orange, λmax=617 nm, or blue, λmax=455 nm.
  • Single-turnover saturating flashes, typically 20-50 µs long. Standard color: red, λmax=630 nm.
  • Continuous actinic light. The maximum intensity is 2,500 µmol(photons).m-2.s-1. Standard color: red, λmax=630 nm, or blue, λmax=455 nm.
  • Additional far-red lightmax=735 nm) for Photosystem I excitation (optional).

Fluorometer FL 3500 Light Scheme / Spectral CharacteristicsFluorometer FL 3500 Light Scheme / Spectral Characteristics
Fluorometer FL 3500 Light Scheme / Spectral Characteristics

Light intensities and timing are software controlled separately for each LED set. The data are processed and the instrument is controlled by the FluorWin software (Windows 95/98/2000/XP compatible). As an option, the customer can also choose light-emitting diodes of different wavelengths. Contact PSI for your specific needs.

  • Detection limit 1 µg Chla/l
  • Four sets of light-emitting diodes – measuring light blue, measuring light red, single-turnover saturating light red, actinic light red
  • Light intensities and timings are software controlled separately for each LED set with 100 ns resolution
  • PIN photodiode detector with 40x variable gain for signal acquisition with 1MHz/16-bit maximum accuracy
  • The instrument capacity can be enhanced by accurate temperature regulation provided by the PSI Thermoregulator and Magnetic Stirrer

    Thermoregulator Magnetic Stirrer
    Thermoregulator / Magnetic Stirrer
  • Probing physiology of aquatic photoautotrophs
  • Measurement of efficiency of PSII photochemistry
  • Estimation of aquatic primary productivity
  • Molecular biology – screening for photosynthetic mutants
  • Detection of abiotic and biotic stress and stress tolerance
  • Taxonomical studies
  • Aquatic bloom detection
  • Chloroplasts & thylakoids
  • Algae & cyanobacteria
  • Small leaves or leaf segments
  • SuperHead Cuvette
    Cuvette in the SuperHead Measuring Unit
  • Fluorescence induction
  • Pulse amplitude modulation measurements (PAM)
  • Fast OJIP transient capture
  • Rapid measurements of QA-reoxidation kinetics
  • State transitions
  • Quenching parameters
  • Photochemical yields
  • Fluorometer in Experimental Setup
  • Creation and archivation of experimental protocols
  • FluorWin Wizard for automated protocols
  • Retrieval and export of experimental data
  • Data manipulation and visualization
  • FluorWin Software: Wizard / Graph WindowFluorWin Software: Wizard / Graph Window
    FluorWin Software: Wizard / Graph Window
  • Measured Fluorescence Parameters:
    F0, FM, FV, F’0, F’M, F’V, FT
  • Light Sources:
    620 nm and 460 nm in standard versions; other wavelengths available as an option
  • Super Pulse Irradiance:
    60,000 µmol(photon).m-2.s-1
  • Actinic Light Irradiance:
    Up to 3,000 µmol(photon).m-2.s-1
  • Custom Defined Protocols:
    Variable timing, special language and scripts
  • A/D Bit Resolution:
    16 bit
  • Detector time response:
    1 µs in FL 3500-F
    4 µs in FL 3500-S
  • Communication Port:
    USB 2.0
  • Weight:
    5 kg
  • Dimensions:
    29 x 20 x 11 cm (Control Box)
    Diameter 16 cm, height 6 cm (SuperHead Measuring Unit)
  • Power Input:
    20 W
  • Electrical:
    90 - 240 V
  • Warranty:
    1 year parts and labor
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  • FRASER J.M., TULK S.E., JEANS J.A., ET AL. (2013): Photophysiological and Photosynthetic Complex Changes During Iron Starvation in Synechocystis sp. PCC 6803 and Synechococcus elongatus PCC 7942. PLoS ONE . Volume 8. DOI:10.1371/journal.pone.0059861
  • KRUPNIK T., KOTABOVA E., VAN BEZOUWEN L. S., ET AL. (2013): A reaction centre-dependent photoprotection mechanism in a highly robust photosystem II from an merolae extremophilic red alga Cyanidioschyzon. Journal of Biological Chemistry. Volume 288. Pages 23529–23542. DOI: 10.1074/jbc.M113.484659
  • SUMMERFIELD T. C., CRAWFORD T. S., YOUNG, R., ET AL. (2013): Environmental pH Affects Photoautotrophic Growth of Synechocystis sp. PCC 6803 Strains Carrying Mutations in the Lumenal Proteins of PSII. Plant &Cell Physiology. Volume 54. Pages 859–874. DOI: 10.1093/pcp/pct036
  • THOMAS S. AND CAMPBELL D. A. (2013): Photophysiology of Bolidomonas pacifica. Journal of Plankton Research. DOI: 10.1093/plankt/fbs105
  • VASS I. Z., KÓS P. B., SASS L., ET AL. (2013): The Ability of Cyanobacterial Cells to Restore UV-B Radiation Induced Damage to Photosystem II is Influenced by Photolyase Dependent DNA Repair. Photochem Photobiol. Volume 89. Pages 384–390. DOI: 10.1111/php.12012
  • VOLGUSHEVA A., STYRING S., MAMEDOV F. (2013): Increased photosystem II stability promotes H2 production in sulfur-deprived Chlamydomonas reinhardtii. Proceedings of the National Academy of Sciences of the United States of America. Volume 110. Pages7223-7228. DOI:10.1073/pnas.1220645110
  • KÁŇA R., KOTABOVA E., SOBOTKA R., ET AL. (2012): Non-Photochemical quenching in Cryptophyte Alga Rhodomonas salina is located in chlorophyll a/c antennae. PLOS ONE . Volume 7. DOI: 10.1371/journal.pone.0029700
  • KATO Y., SHIBAMOTO T., YAMAMOTO S., ET AL. (2012): Influence of the PsbA1/PsbA3, Ca2+/Sr2+ and Cl−/Br− exchanges on the redox potential of the primary quinone QA in Photosystem II from Thermosynechococcus elongatus as revealed by spectroelectrochemistry. Biochimica et Biophysica Acta (BBA) – Bioenergetics. Volume 1817. Pages 1998-2004. DOI: 10.1016/j.bbabio.2012.06.006
  • KVÍDEROVÁ J.(2012): Photochemical performance of the acidophilic red alga Cyanidium sp. in a pH gradient. Orig. Life Evol. Bios. Volume 42. Pages 223-234. DOI: 10.1007/s11084-012-9284-3
  • PERRINE Z., NEGI S., SAYRE R. T. (2012): Optimization of photosynthetic light energy utilization by microalgae, Algal Research, Volume 1. Pages 134-142. DOI: 10.1016/j.algal.2012.07.002
  • QUIGG A., KOTÁBOVÁ E., JAREŠOVÁ J., ET AL. (2012): Photosynthesis in Chromera velia represents a simple system with high efficiency. PLOS ONE. Volume 7. DOI:10.1371/journal.pone.0047036
  • WANG S. AND PAN X. (2012): Effects of Sb(V) on growth and chlorophyll fluorescence of Microcystis aeruginosa (FACHB-905). Current Microbiology. Volume 65. Pages 733 - 741. DOI: 10.1007/s00284-012-0221-5
  • WANG S., ZHANG D., PAN X. (2012): Effects of arsenic on growth and photosystem II (PSII) activity of Microcystis aeruginosa, Ecotoxicology and Environmental Safety, Volume 84. Pages 104-111. DOI: 10.1016/j.ecoenv.2012.06.028
  • ALLAKHVERDIEV S. I., TSUCHIYA T., WATABE K., ET AL. (2011): Redox potentials of primary electron acceptor quinone molecule (QA)− and conserved energetics of photosystem II in cyanobacteria with chlorophyll a and chlorophyll d. PNAS. Volume 108. Pages 8054-8058. DOI:10.1073/pnas.1100173108
  • HAKALA-YATKIN M. AND TYYSTJARVI E. (2011): Inhibition of Photosystem II by the singlet oxygen sensor compounds TEMP and TEMPD. Biochimica et Biophysica Acta. Volume 1807. Pages 243-250. DOI:10.1016/j.bbabio.2010.11.014
  • JEANTHON C., BOEUF D., DAHAN O., ET AL. (2011): Diversity of cultivated and metabolically active aerobic anoxygenic phototrophic bacteria along an oligotrophic gradient in the Mediterranean Sea. Biogeosciences. Volume 8. Pages 1955-1970. DOI:10.5194/bg-8-1955-2011
  • RANTAMAKI S. AND TYYSTJARVI E. (2011): Analysis of S2 QA- charge recombination with the Arrhenius, Eyring and Marcus theories. J. Photochem. Photobiol. B 104. Pages 292-300. DOI:10.1016/j.jphotobiol.2011.03.013
  • KVÍDEROVÁ J. (2010): Rapid algal toxicity assay using variable chlorophyll fluorescence for Chlorella kesslerii (Chlorophyta). Environ. Toxicol. Volume 25. Pages 554-563. DOI: 10.1002/tox.20516
  • KVÍDEROVÁ J. (2010): Characterization of the community of snow algae and their photochemical performance in situ in the Giant Mountains, Czech Republic. AAAR . Volume 42. Pages 210-218. DOI: 10.1657/1938-4246-42.2.210
  • SHIBAMOTO T., KATO Y., NAGAO R., ET AL.(2010): Species-dependence of the redox potential of the primary quinone electron acceptor QA in photosystem II verified by spectroelectrochemistry. FEBS Letters. Volume 584. DOI: 10.1016/j.febslet.2010.03.002
  • PAN X., CHEN X., ZHANG D., ET AL. (2009): Effect of chromium (VI) on Photosystem II activity and heterogeneity of Synechocystis sp. (Cyanophyta): studied with in vivo chlorophyll fluorescence tests. J. Phycol. Volume 45. Pages 386–394. DOI: 10.1111/j.1529-8817.2009.00647.x
  • POLLARI M., RUOTSALAINEN V., RANTAMAKI S., ET AL.(2009): Simultaneous inactivation of sigma factors B and D interferes with light acclimation of the cyanobacterium Synechocystis sp. strain PCC 6803. Journal of Bacteriology. Volume 191.Pages 3992-4001. DOI: 10.1128/JB.00132-09
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  • Orders and Payments
  • Fast Fluorometer FL 3500-F
    9.990,- €
  • Fluorometer Optional Accessories - Infra-Red LED Unit
    1.490,- €
  • Fluorometer Optional Accessories - SuperHead
    3.490,- €
  • Fluorometer Optional Accessories - Thermoregulator TR 2000
    2.999,- €
  • Fluorometer Optional Accessories - Magnetic Stirrer
    998,- €
  • Fluorometer Optional Accessories - Oxygen Detector Module
    1.550,- €
  • Fluorometer Optional Accessories - Oxygen Electrode *
    690,- €

Optional Features and Accessories

Thermoregulator TR 2000
Provides precise temperature control in the range of 0 °C to +70 °C with an accuracy of 0.1 °C. The actual temperature is displayed on the front panel of the device. It includes control unit and temperature controller. TR 2000 can work in two modes: (i) constant mode, (ii) temperature ramp mode. In the constant mode, the instrument maintains a constant temperature of the measured sample. The temperature ramp mode enables linear changing of the sample temperature with a rate ranging from 0.1 °C/sec to 1 °C/sec.

Magnetic Stirrer
Magnetic Stirrer is designed to provide continuous stirring with little speed deviation and minimum heat build-up. Continuous, uniform stirring is essential for keeping a constant temperature within the entire sample volume when the temperature control is applied. The rate of stirring is set by a knob on the front panel of the device. Magnetic Stirrer is a handy accessory to PSI Fluorometers: it can be connected to the Fluorometer Control Unit and controlled by it (switched on and off).

Oxygen Detector
Serves for oxygen evolution detection based on dynamic quenching of fluorescence (electrode sold separately). Important notice: Mechanical construction of the fluorometer does not allow simultaneous measurement of fluorescence and oxygen evolution.

Oxygen Electrode *
Supplement to oxygen detector module.

Infra-Red LED Unit
Allows measuring Fo' and PAR absorbance. It is also used during quenching analysis protocol.

Fluorometer standard configuration can be enhanced by adding a second SuperHead. This SuperHead can be constructed with respect to customer's experimental needs: specific LED colors (Blue, Cyan, Amber) and detection bands (ChlA, ChlB).


FluorWin 3.6
OS: Win2000/XP/Win7 (32bit)/Win8 (32 bit)
Language: English
Size: 1.6 MB

FluorWin 3.7 (for FM 3500/F)
OS: Win2000/XP/Win7 (32bit)/Win8 (32 bit)
Language: English
Size: 1.6 MB

FluorWin 3.7 standard (for FM 3500/S, FM 3500/SM, and FM 3500/LC)
OS: Win2000/XP/Win7 (32bit)/Win8 (32 bit)
Language: English
Size: 1.6 MB

Fluorometer FL3000X User's Guide
Type: PDF
Language: English
Size: 598 KB

Algal Online Monitor Operation Manual
Type: PDF
Language: English
Size: 1.9 MB

FL3500 - Overview of Single Models
Type: PDF
Language: English
Size: 360 KB

Other Fluorometers

Standard Fluorometer FL 3500-S

Highly compact:
Measuring optical head with a standard cuvette for sample suspensions of aquatic or terrestrial plants.

Typical samples:
Suspensions of photosynthetically active organisms, small leaves, or leaf segments.

Fast Fluorometer FL 3500-F

Supported investigations:
- PAM measurements
- Fast kinetic measurements of OJIP
- Flash fluorescence induction
- State transitions etc.

Time resolution of 1 µs.

Algal Online Monitor

Flow-through monitoring:
Enables detection and continuous quantifying of photosynthetically active microorganisms in rivers, lakes, or artificial water reservoirs.

Detection limit: 30 ng Chl/l.

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