What's the difference between using 1x PBS and 10x PBS for analytical applications?

I am developing a sensor that will be used for diagnostic purposes to detect target analytes in biofluids and I've come across several protocols for the testing phase.

Some authors dissolve the target analyte in 1x PBS, while others do that in 10x PBS. Since reports are not consistent, I was wondering if there were any tangible differences in using 1x vs 10x PBS solutions to detect my target analyte.
If so, I'd like an advice on what I should use, considering the following conditions:
- Target analyte: Ascorbic acid
- Expected target biofluid: Saliva