Method of using a cartridge for containing a specimen sample for optical analysis
View Patent ↗A cartridge for holding a test specimen with an extremely small volume. The cartridge has a test chamber and a vestibule through which the test fluids are inserted into the test chamber. The cartridge has a stopper having a pair of seals, the first of which seals the test chamber inlet between the vestibule and the test chamber, and the second of which seals the mouth of the vestibule so that when the stopper is in place, the test chamber is closed to the admission of air or other contaminants and the vestibule is similarly closed against escape of the overflow from the test chamber.
1. A method of sealing a chamber to preclude air entrapment in a test liquid, comprising:
(a) providing an analytical chamber having a test chamber and an overflow reservoir;
(b) filling the analytic chamber with said test liquid to a level below a fill line;
(c) adding a buffer solution having a density not more than the density of the test liquid with a combined volume being sufficient to bring said level of said combined liquids to said fill line;
(d) seating a primary seal within the analytic chamber to form a seal interface that lies between the test chamber and the overflow reservoir within the liquid volume in said analytic chamber, whereby all of said test liquid is retained in said chamber, and air is excluded from said chamber;
(e) retaining any evacuated liquid displaced upon seating said primary seal into said overflow reservoir, and
(f) sealing the overflow with a second seal to preclude voiding of said overflow reservoir and rupturing of said primary seal.
2. A method according to claim 1 , including the steps of
(a) providing a stopper having a primary sealing element adjacent to its distal end and a second sealing element adjacent its proximal end,
(b) inserting the stopper into and through the overflow reservoir to seat the primary sealing element between the test chamber into the reservoir, and thereafter
(c) seating the second sealing element to seal the overflow reservoir.