Reaction receptacle apparatus

A receptacle apparatus for use in performing a chemical or biological assay, the apparatus comprising:

• a plurality of aligned receptacles, each receptacle comprising a hollow body, an open top end and a closed bottom end, wherein the receptacles are capable of interacting with a substance transfer device constructed and arranged to dispense fluid into or withdraw fluid from one or more of the receptacles;
• one or more contact-limiting element holding structures, each contact-limiting element holding structure being adjacent the open top end of at least one of the receptacles and comprising a body having an orifice therein for removably receiving a contact-limiting element;
• one or more contact-limiting elements, each contact-limiting element being associated with one of the contact-limiting element holding structures, wherein the contact-limiting elements are constructed and arranged to be operatively engaged by the substance transfer device to limit contact between at least a portion of the substance transfer device and fluid dispensed into or withdrawn from one or more of the receptacles by the substance transfer device;
• and
• a connecting rib structure fixedly connecting the receptacles to one another, wherein the receptacles, the contact-limiting element holding structures and the connecting rib structure form a single, integral piece.