An automatic multipoint inoculator for the determination of minimum inhibitory concentrations (MICs) of antibiotics in low-income countries: a technical note.

Multipoint inoculator is a laboratory equipment that is used to inoculate with a very high precision a certain number of microorganisms in culture media, in order to determine the minimum inhibitory concentrations (MICs) of antibiotics that would inhibit microbial growth. MICs values are crucial in the control of microbial drug-susceptibility profile for effective infectious disease control and microbial resistance stewardship. The complexity of multipoint inoculator makes it very rare or almost non-existent in developing countries laboratories. In this paper, a robust, precise and, above all, innovative automatic multipoint inoculator is developed. Otherwise, we have implemented double-sided plates with surface-mounted components. These components of Nano-electronics have the advantage that the electrical circuits do no longer have to be drilled, the components can be placed on both sides of the board, and the parasitic electrical inductances are reduced. The equipment enclosure in plexiglas facilitates its sterilization. The device carries Petri dishes that contain culture media, opens them and performs inoculation. It then closes and stores the preparations that are ready for incubation at optimal growth conditions. The present device inoculates at a given concentration of an antibiotic 21 microorganisms simultaneously.