if I wanted to compare a sample to a fixed reference value, I would use the one-sample t-test (or the nonparametric one-sample Wilcoxon signed-rank test).

However, I don't know which test I should use if I want to compare several different samples to that single reference value. Dunnet's multiple comparison test, for example, is meant for comparison against a reference sample/control (consisting of replicates) and not against a single reference value.

Can anyone tell me which statistical test would be appropriate here? The question to be answered by the test(s) is whether there is a statistically significant difference of the samples from the reference value.