Refer the following books

1. 'Analysis, fate and Removal of Pharmaceuticals in the Water Cycle'

2. 'Analysis, Removal, Effects and Risk of Pharmaceuticals in the Water Cycle_ Occurrence and Transformation'

Hi, I think it is possible, it depends on the required QL (quantification limit) for your target compound(s); If you have LCMS, of course it will be nicer, you can do SIM or MRM so you will get very low QL. For some cases I do use UPPLC/HPLC-DAD, for quantification some antibiotics in waste water. We need DAD at least for detecting the identity and purity of the target peak(s). Best regards

Dear Gunawan Indrayanto,

Thank you for your valuable comments. Configuration of HPLC is C18 column and DAD detector. Is it possible to detect the compounds in ng/L range?

Dear Rao Gollapudi, 

Okay. Thank you. We have GC in our laboratory. I will try to analyze using that.

Dear Srimuruganandam sir,

Thank you. I will refer those books.

Hi Padmapriya,

I  do not know, it depends on the respond factor of your compound. You can increase the detect capability by increasing the injector volume, when it is possible, or you can enrichment the concentrations of your target compound by freeze-drying or evaporation, or you can do standard addition method . With best wishes

The advantage of MS detection is that it provides a degree of selectivity that is very difficult to achieve with other techniques. This allows you to detect the compounds of interest in the presence of the high levels if interfering compounds that are likely to be present in environmental samples.

Which pharmaceuticals you are interested in,and what the matrix is will have a huge influence of course, without these specifics nobody can give you specific advice.

With HPLC separation and DAD detection you will need a selective sample cleanup and concentration step that is able to handle sample volumes in the hundred of ml range, If your analytes have strong chromophores you may be able to select a wavelength to give selective detection, or you may be able to do pre- or post-column derivatization.

Depends on what you're searching for, for what quantification limit and if you're searching for one or multiple API and/or their impurity. As far as I can tell doing HPLC-UV (or fluorescence) is doable only if you know what and where to look at the chromatogram, taking care of the opportune extraction steps before injecting ad taking care of opportune derivatization, if necessary. However it may happen to have a "unknown peak" that is suspected to be some metabolite or another similar pharmaceutical and then could be difficult to know what you have at hand with UV only.

ng/L if referred to as single ng/L from contaminated surface water or waste water by means of HPLC-DAD. not completely impossible but in reality not feasable.

as you need about 1 ng on column to get a reasonable signal from a DAD, you would need to extract a lot clean up terrifically and concentrate massively.

1 ng on column if injected 100 µL means 10 ng/ml  extract concentration as you need multiple injections you should probably have at least 500 µl extract volume. i.e. you need 5 ng total.

you need vigorous multistep clean (e.g. size exclusion and SPE on e.g. cyanopropyl SPE) up to remove as much matrix as possible.

to get 5 ng total you would need to extract 5 L of a water sample with 1 ng/L. The most critical is still the matrix and the clean up.

so you need to be VERY (very very very) good at clean ups, extractions and HPLC-DAD to get that done.

kind regards

Kai

It depends on LOQ of your analytical method