The present invention relates to the synthesis and use of a novel trifluorinated bile acid analogue, that being, CA-sar-TFMA which is useful as an imaging probe, diagnostic agent or contrast agent and is resistant to bacterial deconjugation, wherein the trifluorinated bile acid analogue can be used as a 19F MRI tracer exhibiting an increased half-life due to its resistance to choloylglycine hydrolase.