The invention concerns a process for detecting cellular or molecular analytes that employs two types of engineered phages: a capture phage ("bait phage") and a signal phage ("reporter phage"). Through this procedure it is possible to selectively bind and thus recognize the target analyte.

The problem addressed by the present invention is to provide a method for detecting analytes such as, for example, cellular systems (for example bacteria, parasites, eukaryotic cells), viruses, molecular markers (for example toxins, proteins, nucleic acids), preferably of bio-clinical interest, which has 3/15 characteristics of high sensitivity and specificity, which is direct and which can also be used in rapid and economical systems. This invention employs two types of engineered phages: a capture phage ("bait phage") and a signaling phage ("reporter phage"), with characteristics of high sensitivity and specificity and which is rapid and economical. Specifically, phage bait comprises at least one fusion peptide exposed on the major capsomer capable of selectively binding the target analyte. subsequently, the signal phage (reporter) which exposes at least one recognition peptide on the minor capsomer, at the tip of the phage, and at least one marker for signal transduction on the major capsomer, in turn binds the analyte captured by the capture phage. Such a detection system based on two types of engineered phages can be defined as a "molecular sandwich".

• Bio-clinical field;
• Clinical diagnostics;
• Molecular diagnostics.

• Rapid analytical tests in non-laboratory contexts;
• Reduction of high health costs;
• Better analytical solutions for early diagnosis and personalized therapies.