Filtration sampling devices

A sampling device for concentrating a liquid specimen sample, the sampling device comprising a filtration assembly, which comprises:

• a tubular container, which is shaped so as to define an inner wall and a proximal container opening for receiving the liquid specimen sample;
• a plunger, which (i) comprises a plunger head and a plunger rod, which has a distal end portion to which the plunger head is coupled, and (ii) is insertable into the tubular container via the proximal container opening, such that a lateral surface of the plunger head forms a fluid-tight movable seal with the inner wall of the tubular container;
• a waste liquid receptacle;
• a filter;
• a filter support, which is shaped so as to define (a) a support surface on which the filter is removably disposed, and (b) a plurality of filtrate-passage openings through the filter support into the waste liquid receptacle;
• a container housing;
• and
• a plunger support, which is (a) coupled to a proximal portion of the plunger, and (b) hingedly attached to the container, so as to enable a change in orientation between a central longitudinal axis of the plunger and a central longitudinal axis of the container housing,
• wherein the plunger, the plunger support, and the container housing are arranged such that the change in orientation transitions the proximal container opening from an open position to a closed position, in which the plunger head covers the proximal container opening.

A method for concentrating a liquid specimen sample, the method comprising:

• placing, via a proximal container opening while the proximal container opening is in an open position, the liquid specimen sample in a tubular container of a filtration assembly of a sampling device, wherein the sampling device further includes (i) a container housing, (ii) a waste liquid receptacle, (iii) a filter, and (iv) a filter support, which is shaped so as to define (a) a support surface on which the filter is removably disposed, and (b) a plurality of filtrate-passage openings through the filter support into the waste liquid receptacle;
• thereafter, transitioning the proximal container opening from the open position to a closed position, in which a plunger head of a plunger of the filtration assembly covers the proximal container opening and a lateral surface of the plunger head forms a fluid-tight movable seal with an inner wall of the tubular container, wherein the plunger further comprises a plunger rod, which has a distal end portion to which the plunger head is coupled;
• and
• pushing at least a portion of the liquid specimen sample through the filter and the filtrate-passage openings and into the waste liquid receptacle,
• wherein transitioning comprises changing an orientation between a central longitudinal axis of the plunger and a central longitudinal axis of the container housing by moving a plunger support, which is (a) coupled to a proximal portion of the plunger, and (b) hingedly attached to the container so as to enable the change in the orientation.

A sampling device for concentrating a liquid specimen sample, the sampling device comprising a filtration assembly, which comprises:

• a container housing, which (a) is shaped so as to define one or more first threads, and (b) comprises a tubular container, which is shaped so as to define an inner wall and a proximal container opening for receiving the liquid specimen sample;
• a plunger support, which is shaped so as to define one or more second threads, shaped so as to engage the one or more first threads;
• a plunger, which (a) comprises a plunger head, (b) is insertable into the tubular container via the proximal container opening, such that a lateral surface of the plunger head forms a fluid-tight movable seal with the inner wall, and (c) is coupled to the plunger support, such that rotation of the plunger support with respect to the container housing, when the one or more second threads are engaged with the one or more first threads, distally advances the plunger support with respect to the container housing and thus the plunger within the tubular container;
• a filter, wherein the filtration assembly is configured such that movement of the plunger head within the tubular container, when the liquid specimen sample is contained in the tubular container and the filter is disposed in the tubular container, pushes at least a portion of the liquid specimen sample through the filter;
• a torque-limiting clutch;
• and
• a control knob, which is rotatable about a central axis of the plunger, and which is coupled to the plunger support by the torque-limiting clutch, such that rotation of the control knob by application of:
• a torque less than a threshold value rotates the plunger support, thereby rotating the plunger support with respect to the container housing, and
• a torque equal to the threshold value causes the control knob to slip with respect to the plunger support.

A method for concentrating a liquid specimen sample, the method comprising:

• placing, via a proximal container opening, the liquid specimen sample in a tubular container of a container housing of a filtration assembly of a sampling device, wherein the container housing is shaped so as to define one or more first threads;
• inserting a plunger head of a plunger of the filtration assembly into the tubular container via the proximal container opening of the tubular container, such that a lateral surface of the plunger head forms a fluid-tight movable seal with an inner wall of the tubular container, wherein the plunger further comprises a plunger rod, which has a distal end portion to which the plunger head is coupled;
• engaging the one or more first threads with one or more second threads defined by a plunger support coupled to the plunger;
• and
• rotating, about a central axis of the plunger, a control knob that is coupled to the plunger support by a torque-limiting clutch, such that rotation of the control knob by application of:
• a torque less than a threshold value rotates the plunger support, thereby rotating the plunger support with respect to the container housing and advancing the plunger support with respect to the container housing and thus the plunger within the tubular container, so as to push at least a portion of the liquid specimen sample through a filter disposed in the tubular container, and
• a torque equal to the threshold value causes the control knob to slip with respect to the plunger support.