Z980 Probe AquaPen

The Z980 Probe AquaPen is a handheld fluorometer that enables rapid and accurate measurement of photosynthetic parameters in suspensions. It is equipped with a blue measuring light (optional red or white LED is available) that suits investigations of algal suspensions. The measurements are carried out by a submersible optical probe. The AquaPen has high sensitivity (up to 0.5 μg Chl/L) and it can even be used in measurements of natural water samples in the field containing low concentrations of phytoplankton. It is designed for both the lab and field applications and is ideal in teaching.

The Z980 Probe AquaPen includes the chlorophyll fluorescence kinetics protocols for measurements of OJIP, NPQ and Light Curve responses of QY.  Data transfer option via Bluetooth and USB communication technology are included.  It comes with PC software for data transfer and visulization. With a built-in GPS and rechargable Li-ion batteries it is ideal for use inthe field. A cuvette (Z985) version of the AquaPen allows the same chlorophyll fluorescence plus OD (680 and 720nm) measurements in suspension contained in a 4 ml cuvette and placed inside the holder.

  • Hand-held chlorophyll fluorometer for algal suspensions
  • Probe may be placed directly in the suspension, including natural bodies of water
  • Ideal for field studies
  • High chlorophyll detection sensitivity – up to 0.5 ug chl/L
  • PC Software and data transfer via USB and Bluetooth included
  • Li-ion rechargable battery
  • GPS module built in

NPQ and Light Curve Protocols

  • Three predefined NPQ protocols differing in the duration of light exposure and dark recovery phase as well as in the number of intervals between the pulses
  • Typically used for quantification of photochemical and non-photochemical quenching in dark-adapted samples
  • NPQ 1 protocol: light duration 60s, 5 pulses; dark recovery duration 88s, 3 pulses
  • NPQ 2 protocol: light duration 200s, 10 pulses; dark recovery duration 390s, 7 pulses
  • NPQ3 protocol:light duration 200s, 10 pulses; dark recovery duration 60s, 2 pulses
  • Three predefined protocols differing in number and duration of light phases and light intensities
  • Based on pulse modulated fluorometry (PAM)
  • The effective quantum yields of photosynthesis are determined under various light intensities of continuous illumination.
  • Light response curve relating the rate of photosynthesis to photon flux density
  • LC1 protocol: 6 phases with 60s duration (10, 20, 50, 100, 300, 500 uE)
  • LC2 protocol: 5 phases with 30s duration (100, 200, 300, 500, 1000uE)
  • LC3 protocol: 7 phases with 60s duration (10, 20, 50, 100, 300, 500, 1000uE)

Software – Sample Data

Sample NPQ data

Sample OJIP data

OJIP parameters
  • Bckg = background
  • F0: = F50µs; fluorescence intensity at 50 µs
  • FJ: = fluorescence intensity at j-step (at 2 ms)
  • Fi: = fluorescence intensity at i-step (at 60 ms)
  • FM: = maximal fluorescence intensity
  • FV: = FM – F0 (maximal variable fluorescence)
  • VJ = (FJ – F0) / (FM – F0)
  • Vi = (Fi – F0) / (FM – F0)
  • FM / F0
  • FV / F0
  • FV/ FM
  • M0 or (dV / dt)0 = TR0 / RC – ET0 / RC = 4 (F300 – F0) / (FM – F0)
  • Area = area between fluorescence curve and FM (background subtracted)
  • Fix Area = total area above the OJIP fluorescence transient – between F40µ and F1s(background subtracted)
  • SM = area / FM – F0 (multiple turn-over)
  • Ss = the smallest Sm turn-over (single turn-over)
  • N = SM . M0 . (1 / VJ) turn-over number QA
  • Phi_P0 = 1 – (F0 / FM (or FV / FM)
  • Psi_0 = 1 – VJ
  • Phi_E0 = (1 – F0 / FM)) . Psi_0
  • Phi_D0 = 1 – Phi_P0 – (F0 / FM)
  • Phi_Pav = Phi_P0 – (SM / tFM); tFM) = Time to reach FM (in ms)
  • ABS / RC = M0 . (1 / VJ) . (1 / Phi_P0)
  • TR0 / RC = M0 . (1 / VJ)
  • ET0 / RC = M0 . (1 / VJ) . Phi_0)
  • DI0 / RC = (ABS / RC) – (TR0 / RC)

Formulas Derived From:
R.J. Strasser, A. Srivastava and M. Tsimilli-Michael (2000): The fluorescence transient as a tool to characterize and screen photosynthetic samples. In: Probing Photosynthesis: Mechanism, Regulation and Adaptation (M. Yunus, U. Pathre and P. Mohanty, eds.), Taylor and Francis, UK, Chapter 25, pp 445-483.