Combination glass/plastic pipet tip assembly

Claim 1

A pipette tip assembly comprising a glass nozzle and a resilient plastic collar, said nozzle comprising a substantially cylindrical body having a first body end portion with a first rim and a second body end portion, aid first body end portion having an exterior surface with given outer diameter, said second body end portion being tapered, said collar comprising a substantially cylindrical body having a first collar end portion for mounting the assembly on a pipettor end and a second collar end portion for receiving said first body end portion, said first collar end portion being outwardly flared and adopted to receive the pipettor end, means in said first collar end portion to prevent insertion of the pipettor end into said collar beyond said first collar end portion, said second collar end portion comprising an interior surface and a second rim, said interior surface of said second collar end portion having a diameter slightly smaller than said outer diameter of said first body end portion such that said second collar end portion expands when said first body end portion is received therein, means protruding from said interior surface of said second collar end portion, at a location spaced from said second rim, said first body end portion being adapted to be received within said second collar end portion with said first rim proximate said protruding means.