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Dmorty217
09/30/2016, 11:27 AM
I'm going to purchase a Spectrometer to test for Chloroquine Phosphate in my tank but I am unable to find what it is I'm specifically suppose to test for in order to get the concentration in my tank? Any and all help is greatly appreciated!

bertoni
09/30/2016, 06:52 PM
Could you give us a pointer to the kit that you're buying. I'm not clear on what it detects yet.

Dmorty217
10/01/2016, 06:46 AM
I was told someone that works for a public aquarium that they use a Hach DR5000 to test for CP in their systems and the program is built into the Spectophotometer. I'm still waiting to figure out what part of the program ( I looked at the manual online and it tests for many many things) he uses to test for Chloroquine. I called Hach but they needed more information from me I was unable to provide. The DR6000 costs $8400 and I believe that Hach can provide me another product they sell that's cheaper but will also provide the same results as the much more expensive DR6000 ( the 5000 is no longer made)

bertoni
10/01/2016, 04:58 PM
I looked at the structure, and I'm not sure what they are testing. Sorry! I'm not a chemist.

halleffect
10/01/2016, 09:44 PM
I'm going to purchase a Spectrometer to test for Chloroquine Phosphate in my tank but I am unable to find what it is I'm specifically suppose to test for in order to get the concentration in my tank? Any and all help is greatly appreciated!

I only know what a few google searches have managed to tell me. from what I gather Chloroquine phosphate is used to treat marine fish for a broad spectrum of diseases such as ich, velvet, brook (in humans it is used to treat malaria, so i guess it makes sense). I had never heard of it before. So another search led to an article that says the following on measuring its concentration:

There is no test kit to measure the chloroquine concentration in water as there is for many copper medications. Public aquariums and laboratories with access to a UV spectrophotometer can use it to measure chloroquine in the water directly. How this works is that at 329 nm, chloroquine in water absorbs ultraviolet light in proportion to its concentration. Using a quartz cuvette that is transparent to UV, a blank sample of untreated water is first measured. Then, a sample of that water is dosed with a serial dilution of chloroquine in the range to be treated, typically 2.5, 5, 10, 20 and 25 mg/l and the percent transmittance is measured for each sample. Once this standard trend line is graphed, the chloroquine concentration of any water sample within that range can be measured. Because other organic compounds can be present in aquarium water that may also absorb UV light, it is best to create a standard curve for each water system prior to treatment.

http://http://www.advancedaquarist.com/2013/2/fish

Ghost25
10/02/2016, 01:46 AM
Can you explain why you feel this is necessary? Presumably you are dosing a QT tank but why do you need to activly monitor the dosage? Surely it would be easier to just mix up fresh solution if you are concerned that chloroquine levels decreased.

Anyway here is a paper on the subject: http://www.ajpcr.com/Vol6Suppl1/1575.pdf

You will need to make a standard curve by measuring the absorbance of known samples (in saltwater). In the linked paper they measure A285 and A345 in acid treated samples using alkaline samples as a blank (presumably the chloroquine hydrochloride is UV active and the freebase is not). You could probably get away with just the A345 but it depends on the accuracy you need.

Dmorty217
10/02/2016, 06:52 AM
Can you explain why you feel this is necessary? Presumably you are dosing a QT tank but why do you need to activly monitor the dosage? Surely it would be easier to just mix up fresh solution if you are concerned that chloroquine levels decreased.

Anyway here is a paper on the subject: http://www.ajpcr.com/Vol6Suppl1/1575.pdf

You will need to make a standard curve by measuring the absorbance of known samples (in saltwater). In the linked paper they measure A285 and A345 in acid treated samples using alkaline samples as a blank (presumably the chloroquine hydrochloride is UV active and the freebase is not). You could probably get away with just the A345 but it depends on the accuracy you need.

I read this same article. It's necessary to me since I had a frag bring Ich in my DT and dosed 60mg/gallon of CP and it had zero effect on the Ich because of available bacterial capacity in my DT. I then dosed half again what was called for but I have no idea the concentration in my DT. I have resorted to using copper, which I don't like using at all and my fish don't appreciate it much either. I want to be able to test for CP since I have far too much invested time and money alike. Taking all my fish out and putting them thru QT again is a option but one I would rather avoid if possible. Fallow times for Ich are a joke (current frag was fishless since Jan 1, so 9 months and well the Ich was still present)

disc1
10/02/2016, 10:28 AM
Chloroquine absorbs UV light all by itself. All you need is a UV spec so you can read the absorbance. It has a very broad absorbance, so anything between about 310nm up to about 350nm should work. Looks like the peak is around 342nm. You'll also need to make up some standards to calibrate against. But no other reagents are needed, just a spec, a cuvette, and Beer's law.

Dmorty217
10/02/2016, 11:40 AM
Chloroquine absorbs UV light all by itself. All you need is a UV spec so you can read the absorbance. It has a very broad absorbance, so anything between about 310nm up to about 350nm should work. Looks like the peak is around 342nm. You'll also need to make up some standards to calibrate against. But no other reagents are needed, just a spec, a cuvette, and Beer's law.

Thank you David, this is helpful. Now to find a semi affordable UV spectrophotometer!