Non-displasive pipette

A non-displasive pipette configured for connection to a tip having a fluid prepackaged therein, the tip including an opening in a first end thereof, an orifice in a second end thereof to allow for the discharge of the fluid therefrom, and a passageway therebetween for receiving the fluid, the non-displasive pipette comprising:

• a body having an inner surface defining a chamber therethrough and having first and second opposite ends, the second end of the body insertable into the passageway through the opening in the first end of the tip to a fully inserted position;
• a plunger having an outer surface and being slidably received in the first end of the chamber of the body, the plunger moveable in the chamber between a first extended position and a second depressed position;
• an air escape passage extending through the plunger, the air escape passage configured to allow air from the chamber to escape therefrom in response to insertion of the second end of the body into the passageway of the tip;
• and
• a seal for selectively sealing the air escape passage and preventing air from escaping the chamber with the second end of the body in the fully inserted position, a seal extending about the plunger and forming a sealing interface with the body;
• wherein:
• the plunger includes a first end, a second end receivable in the chamber of the body and an outer surface;
• the air escape passage extends through the plunger and intersects the outer surface of the plunger at a first location;
• and
• the seal extends about the outer surface of the plunger between the first location and the first end of the plunger with the plunger in the second depressed position.

A non-displasive pipette, comprising:

• a tip configured for receiving a fluid therein, the tip extending along an axis and including an opening in a first end thereof, an orifice in a second end thereof to allow for the discharge of the fluid therefrom, and a passageway therebetween for receiving the fluid;
• a body having an inner surface defining a chamber therethrough and having first and second opposite ends, the second end of the body insertable into the passageway in the tip through the opening in the first end of the tip to a fully inserted position;
• a plunger having an outer surface and being slidably received in the chamber at the first end of the body, the plunger moveable with the chamber between an extended position and a discharge position wherein the fluid is urged from tip through the orifice;
• and
• an air discharge arrangement configured to allow air from the chamber to escape therefrom and to maintain the fluid in the tip in response to insertion of the second end of the body into the passageway of the tip;
• a seal having an outer surface with a first portion engaged with and forming an airtight seal with the inner surface of the body at a location adjacent the first end of the body and a second portion engaged with and forming an airtight seal with the outer surface of the plunger;
• and
• a sealing mechanism movable between a first position wherein air is allowed to escape from the chamber and a second position wherein the sealing mechanism is configured to seal the air escape passage and prevent air from escaping the chamber with the second end of the body in the fully inserted position;
• wherein fluid in the passageway of the tip remains therein during insertion of the second end of the body into the passageway of the tip.