A method of recovering an enzyme activity, such as reverse transcriptase activity, from enveloped viruses, such as HIV, in a biological sample containing a non-protected enzymes, is described. The bottom part is constituted by a sheet of a thermoplastic material joined to the bottle body by thermowelding. The first workstation sends to a server, via one or more networks, a definition of the electronic sticky note and the specification of the one or more workstations to receive and display the electronic sticky note.