A sample of material such as blood, urine, spinal fluid, or the like to be tested for the presence of biological activity is placed into a sterile container together with a suitable growth medium which includes a C.sup.14 carbon containing carbon source (such as C.sup.14 substituted glucose) which is fermentable to produce gaseous C.sup.14 O.sub.2. An incubator is provided for exposing the container and its contents to conditions conducive to growth. After a suitable incubation period, a portion of the gaseous atmosphere in the container is withdrawn and analyzed in gaseous form in an ionization chamber for the presence of radioactivity. Valve and conduit means are provided for analyzing a number of samples sequentially.

Mixed culture interactions can be studied by providing a fluid tight housing defining a central diffusion reservoir for carrying a liquid culture nutrient medium. The housing is provided with a plurality of discrete radially extending organism growth chambers for culturing organisms in the liquid culture nutrient medium. Each organism growth chamber communicates with the central diffusion reservoir and each organism growth chamber is radially spaced on the periphery of the central diffusion reservoir. Each organism growth chamber is provided with means for controlling communication between the organism growth chamber and the central diffusion reservoir.

An improved apparatus and method for the collection, cultivation and identification of microorganisms obtained from body fluids is disclosed. The apparatus includes an evacuated tube containing a culture medium, an inert gaseous atmosphere and a vent-cap assembly. The tube containing the culture medium is fitted with a stopper for introduction of body fluid by means of a cannula and after growth of the organisms, transfer of the cultured medium is completed for sub-culturing or identification procedures.

A sterilization indicator for testing the effectiveness of a sterilization process and a sterilization process using such an indicator are described. The indicator comprises a first compartment having at least one open end; a gas-permeable, bacteria-impermeable closure covering said open end; said first compartment containing a number of viable microorganisms that are resistant to a related sterilization process; a second compartment moveable with respect to said first compartment; said second compartment having a predetermined quantity of nutrient medium for promoting the growth of said microorganisms; separation means for sealing the nutrient medium in said second compartment; communications means for providing communication between said first compartment and said second compartment when it is desired to contact said microorganisms with said nutrient medium; and a detector composition contained in one of said compartments that is capable of undergoing a detectable change in response to the growth of said microorganisms.

A container has a single primary chamber linked to a single secondary chamber via a common wall in which has been fused a semi-permeable membrane. A lid for the primary chamber enables sealing of a sample (not shown) inserted into the primary chamber, sealingly enclosing any dangerous fraction of the sample, which fraction and the lid closed any infectious material hermetically sealed in as this cannot cross the semi-permeable membrane, due to the latter being provided with a cut-off matched to the molecular size of the type of sample with which the container is to be used. However, material of a lower molecular weight than the dangerous fraction can move across the membrane in either directions by dialysis or osmosis.