For our chlorophyll PN 10-850 shipments, we typically add an icepack. This isn’t so they re-mail frozen, but to help with transit so the standards don’t experience a huge rise in temperature. We also ship them overnight so receiving them a day later is okay versus receiving them many days later. Chlorophyll won’t degrade at room temperature. We actually warm the standard to room temp (~22 degrees C) prior to using it or calibrating. The primary degradation pathways are light and oxidation. Extreme temperatures will definitely degrade chlorophyll, however, if you received the standards next day at the temperatures you stated, which seem to be cooler than room temp, the standards should be okay as long as the package was not opened when you received it. What I would do is store them in a -20 degree C, or colder, freezer if you plan to keep them for a year. Please make sure the standards are not broken open when storing for that long of a period. I don’t believe your standards have degraded.
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Using the EPA 445 methodology, there is an entire process that you can follow along to make PN 10-850 chlorophyll a standard. You can find documentation for the EPA 445 methodology online or via our website: Fluorometer Applications | Turner Designs | United States.
To get started, you will need to purchase the chlorophyll a powder. A good example is from Sigma Aldrich.
Then you will need a solvent like Acetone, have available a spectrophotometric analysis that has been properly maintained and calibrated, and a bottling procedure with associated materials.

Yes, your statement is correct that the PN 10-850 chlorophyll a standard comes with two ampoules, 20 mL each. One will be the high standard typically around 200 µg/L and one is the low standard around 20 µg/L.

Unfortunately, the PN 10-850 chlorophyll a standards are not the same as PN 10-950 Spectrophotometric chlorophyll a standards. For use with our instruments, the PN 10-850 are at a low enough concentration to be used with the Trilogy since their range is in the µg/L. With the PN 10-950, the concentrations are in the mg/L which exceeds the range of our Trilogy Benchtop fluorometers.

We have made the decision to discontinue the 10-950 spectrophotometric chl a standards.

It is important to note that the 10-850 chlorophyll a standards are not suitable for use with EPA method 446. The 10-850 chlorophyll a standards offers two ampoules with concentrations of around 200 µg/L and 20 µg/L, whereas the 10-950 spectrophotometric chlorophyll a standards are designed for use with a spectrophotometer and are set at higher concentrations in the mg/L. Visually, the PN 10-950 will appear as a cloudy green solution while the PN 10-850 will appear see-through. As an alternative, you can purchase powder from a scientific distributor, like Sigma Aldrich. You may follow various online journals describing reconstitution of powder with a solvent and create your own concentrations.

Chlorophyll a Standards must be stored at -20° C in their original foil wrap and opened under subdued lighting conditions. We do not recommend leaving the containers in direct sunlight or exposed to temperature swings. Please follow the guidelines set by the EPA method 445.

The chlorophyll a standards will need to come to room temperature before beginning the sample analysis with acidification or non-acidification procedures. We recommend removing the sample from the freezer 30 minutes before use. This makes the standards easier to handle and reduces the risk of condensation on cuvettes or test tubes.
As phrased in the EPA method 445 section 4.4, "Samples, standards, LRBs and QCSs must be at the same temperature to prevent errors and/or low precision. Analyses of samples at ambient temperature is recommended in this method. Ambient temperature should not fluctuate more than ± 3EC between calibrations or recalibration of the fluorometer will be necessary."

The chlorophyll from spinach purchased from Sigma Aldrich is stated as >85% HPLC and Chl b essentially free. The chlorophyll from algae purchased from Sigma Aldrich is Chl b free because Anacystis doesn’t contain chlorophyll b whereas spinach does. So, your spinach chlorophyll may have some degree of chl b contamination which means it’s not pure chlorophyll a with respect to making standards for the purpose of calibrating for chlorophyll a. For the chlorophyll a standards that we provide, they are pure chlorophyll a with no contamination.

In terms of calibration, you can check to see if the chlorophyll a standards has degraded using the acidification Trilogy module and run it like a normal sample. If all you have is the non-acidification, there’s no easy way to tell if degradation has occurred.

We recommend that you read up on our help article on the purpose of the Solid Standard Check and whether it can be used for calibration: Using a Solid Standard for Instruments | Turner Designs Help Center

There are one of three things that can happen if you over tighten the solid standard check.

We recommend aligning your solid standard check the same was as shown in the image below:
The handle tab should be at the rear farthest away from you. The orientation of the Solid Standard check matters greatly to reduce errors caused by insertion variability.

To reduce the errors and variability, we recommend inserting the Solid Standard Check the same way, in the same orientation every single time. You may find that the readings may differ greatly from each other by more than +/-2.5% due to introduced variability.

Temperature will affect the Solid Standard Check. To reduce the errors and variability, we recommend using the Solid Standard Check the same way, in the same temperature every single time when in use with our instruments. You may find that the readings may differ greatly from each other by more than +/-2.5% due to introduced variability.

While the Solid standard checks are far more stable than liquid calibration standards, they do have an eventual shelf life. Dust and many other environmental factors can wear down the solid standard check overtime even with the best storage. To prolong its use, it is important to maintain good practices with storage such as keeping it away from direct sunlight, storing inside of the box it came with in a temperature-controlled environment and away from areas prone to high humidity, dust, or otherwise.

Many of the instruments we have use shade caps. Our C3, C6p, C-FLUOR, Cyclops-7F, FluoroSense, and the Handheld Little Dipper all benefit from this valuable accessory.
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Submersible probes and handheld instruments often face challenges from constant battering from waves or direct sunlight in field environments. To ensure accurate measurements and as an added bonus to protect your equipment, we strongly recommend using the shade cap. It provides a fixed distance for sample measurement, minimizing the effects of ambient light. Additionally, the shade cap safeguards the optics from damage during deployment, recovery, and transport, especially in fast-flowing or shallow environments. Protect your investment and ensure reliable results with the shade cap.

For all of our liquid calibration solutions with PTSA Dye, Fluorescein Dye, or Rhodamine WT dye, the shelf life is 1 year as marked on the label attached to the calibration solution bottle.

Check out our article on MSDS for the liquid calibration solutions: Safety Data Sheets | Turner Designs Help Center

It is recommended that the liquid calibration solutions be stored in room temperature in a shelf away from direct sunlight. Freezing temperatures will degrade the liquid calibration solutions.

We are unable to provide you with pricing nor can we make customer requested concentrations for liquid calibration solutions. If you wish to make your own liquid calibration solutions at concentrations different than the ones we provide, we recommend using the raw dye that can be purchased from various manufacturers. We do offer PN 10-108, Rhodamine WT dye 20% concentrate 8 oz. and PN 10-109, 40% Fluorescein Concentrate, 8 oz. PTSA powder can be purchased from Sigma Aldrich or Spectra Trace.

We do have written instructions on how to dilute the raw dye or liquid calibration solutions to a desired concentration. Help article available here: Fluorescent Dye Tracing | Turner Designs Help Center. Use Deionized water and calibrated pipettes for best results.

Fluorescein dye will degrade much quicker than Rhodamine dye under sunlight. How quick it degrades is dependent on light availability. The more light, the quicker the degradation.

Rhodamine B is related to Sulphorhodamine B. Rhodamine RWT was developed to overcome a disadvantage of rhodamine B, which was the adsorption on suspended sediment. The same modification was also expected to reduce toxicity, and limited testing confirmed this. Additionally, fluorescent yield of Sulphorhodamine B is not as good as Rhodamine RWT and B. http://docs.turnerdesigns.com/t2/doc/appnotes/998-5000.pdf

Particulate matter will greatly affect the accuracy of the instrument when reading for dyes because the particles will block the light path.

Our calibration standards for Fluorescein are free acid and not sodium salt.

You purchase this as powder called Quinine Sulfate Dihyrate salt for the CDOM application with the AquaFluor and Trilogy fluorometers. The CAS no is 207671-44-1. Here are some links to buy from:

We have PTSA standard solution for calibrating the Cyclops-7F units. The PTSA would be a proxy for Quinine Sulfate so you wouldn’t have to use the harsh chemicals, instead you can use our PTSA calibration solutions and get the same result. CDOM calibration can be done if you have quinine sulfate available. If you do not require a correlation and instead need it for a base line check. You can run a calibration yourself with a DI water blank and a sample from the body of water you are testing that you know has CDOM in it, then call that some arbitrary number say 100 mV and any sample afterwards can tell you if it’s higher or lower concentration than the sample you put in.

PN 7000-959 methacrylate cuvettes are the standard 10 x 10 mm sizing.

PN 7000-957 polystyrene cuvettes are the standard 10 x 10 mm sizing.

PN 7000-957 polystyrene cuvettes are the recommended type for the AquaFluor and Trilogy Turbidity applications.

PN 7000-957 polystyrene cuvettes are not the same as PN 7000-959 methacrylate cuvettes. Due to the way they are made, they allow for different wavelength ranges through. Infrared passes through polystyrene better than methacrylate.

For the acidification application, glass or quartz materials are preferred when in use with strong solvents. Plastics will degrade under solvents like acetone and will greatly reduce the instrument's ability to read a sample. At worst, solvents may degrade the plastic, causing leaks and damaging the instrument.

PN 10-029A glass round bottom test tubes are a 12 x 75 mm sizing.

Unfortunately, we no longer sell test tubes for the 10-AU or TD-700. However, we can provide you with the sizing on those test tubes and buy them as standards from Scientific Distributors like Sigma Aldrich or ThermoFisher Scientific. We have used 25 mm x 150 mm Borosilicate Test Tubes and a 13 mm x 100 mm Borosilicate Test Tubes.

You can certainly reuse the methacrylate cuvettes in use with the Opti-Check handheld fluorometer. Be sure to minimize spills on the sides. Constant wiping of the plastic sides degrades the plastic over time. When the optical face is clear, it can still hide micro abrasions that are hard to see with the naked eye. A thoroughly scratched cuvette surface on the cuvette will affect the accuracy of the readings and should be replaced immediately before the next use. Be sure to rinse the cuvette out 3 times with deionized water after use.