Apparatus and method for dilution and mixing of liquid samples

A method of diluting a sample with a diluent, comprising:

• adding an unmeasured volume of said sample to sample application site means of a device in which said sample flows by the sum of capillary and gravitational forces to measuring chamber means having a first volume, said measuring chamber means being terminated by a stop flow junction which stops sample flow as a result of back pressure resulting from interaction of said sample with wall means of said device at said stop flow junction, said device further comprising receiving chamber means having a second volume greater than said first volume, said receiving chamber means being located in fluid receiving relationship to said measuring chamber means;
• then adding said diluent to diluent application site means of said device, wherein said diluent flows by the sum of capillary and gravitational forces to said measuring chamber means;
• and
• then starting flow at said stop flow junction, wherein said starting flow comprises:
• moving said device, whereby said moving overcomes said back pressure and allows sample and diluent to flow through said stop flow junction into said receiving chamber means,
• whereby a fixed ratio of sample and diluent fills said receiving chamber means.

A method of diluting a sample with a diluent, comprising:

• adding an unmeasured volume of said sample to sample application site means of a device in which said sample flows by the sum of capillary and gravitational forces to measuring chamber means having a first volume, said measuring chamber means being terminated by a stop flow junction which stops sample flow as a result of back pressure resulting from interaction of said sample with wall means of said device at said stop flow junction, said device further comprising receiving chamber means having a second volume greater than said first volume, said receiving chamber means being located in fluid receiving relationship to said measuring chamber means;
• then adding said diluent to diluent application site means of said device, wherein said diluent flows by the sum of capillary and gravitational forces to said measuring chamber means;
• and
• then starting flow at said stop flow junction, wherein said starting flow comprises contacting liquid present at said stop flow junction with a moveable part of said apparatus, wherein sample and diluent flow through said stop flow junction into said receiving chamber means, whereby a fixed ratio of sample and diluent fills said receiving chamber means.