Methods and systems for determining the concentration of one or more analytes from a sample such as blood or plasma are described. The systems described herein can be configured to withdraw a certain volume of sample from a source of bodily fluid, direct a first portion of the withdrawn sample to an analyte monitoring system and return a second portion of the sample to the patient. The analyte monitoring system can include an automated blood withdrawal system that is configured to withdraw blood from the patient's vasculature at low pressure and/or withdrawal rates so as to reduce or prevent contamination of the withdrawn fluid from the infusion fluids.

A sampling apparatus can have an elongate tube and a liquid partitioning unit, first port can receive an incoming flow of test liquid and a second port may be coupled to the elongate tube. The liquid partitioning unit can combine the flow of test liquid with a plurality of partitioning elements to define a plurality of discrete liquid samples for movement along and storage in the elongate tube.

A method for performing an assay to determine the presence or concentration of an analyte contained in a sample of body fluid by using a device comprising at least one analyte quantification member and a sensor associated therewith, the method includes: applying a first sample to the analyte quantification member; and detecting the presence or absence of an adequate sample volume; wherein upon detection of the absence of an adequate sample volume, initiating a finite timed period, and signaling the user to introduce a second sample of body fluid to the analyte quantification member. Associated arrangements and devices are also disclosed.

A blood separation device adapted to receive a blood sample having a whole blood portion and a plasma portion is disclosed. The blood separation device includes a housing defining a first chamber, a second chamber, and a separation member disposed therebetween. The blood separation device also includes an actuator, wherein actuation of the actuator draws the blood sample into the first chamber and the separation member is adapted to allow the plasma portion to pass through the separation member to the second chamber. The blood separation device matches the plasma chamber volume, the blood chamber volume, and the applied single pressure source so that the correct trans-membrane pressure and shear rate is obtained.

Medical device assemblies capable of aspirating liquid into a syringe barrel or other medical devices while evacuating any air from the syringe are described. An exemplary medical device includes a syringe barrel, plunger rod and stopper assembly having an air permeable and liquid impermeable porous portion and structure for forming a vacuum within either the stopper or the plunger rod. Described is a medical device including a syringe barrel, plunger rod and stopper assembly having an air permeable and liquid impermeable porous portion and structure for forming a vacuum within chamber between the stopper and plunger rod wherein the plunger rod includes a sealing edge and is moveable relative to the stopper. Exemplary medical devices may include a vent for allowing air that permeates through the porous portion to escape to atmosphere. Methods for aspirating a syringe barrel with a liquid are also provided.

Disclosed herein are evacuated blood collection tubes comprising protease inhibitor cocktails in liquid form and uses thereof for assessing features associated with the contact system in a subject, including the endogenous level of contact system activation, the endogenous level of a drug that targets a component of contact system during treatment, and/or the immunogenicity of such a drug.

A syringe for obtaining nano-sized components from a solution includes a barrel having an interior, a needle extending from one end of the barrel, and a plunger received in the interior at an end of the barrel opposite the needle. A filter cartridge is positioned between the needle and the barrel, wherein the filter cartridge maintains at least one membrane having apertures of two distinct size ranges, and wherein operation of the plunger to draw the solution into the barrel allows for retention of nano-sized components of a size between the two distinct size ranges.

A blood sample collection system, may include a housing, the housing including a blood collection port; and a baffle chamber; a needle formed through the housing and into the blood collection port; and a baffle formed within the baffle chamber to counteract a vacuum within a blood collection tube when pierced by the needle.

A biological fluid separation device that is adapted to receive a multi-component blood sample is disclosed. After collecting the blood sample, the biological fluid separation device is able to separate a plasma portion from a cellular portion. After separation, the biological fluid separation device is able to transfer the plasma portion of the blood sample to a point-of-care testing device. The biological fluid separation device of the present disclosure also provides a closed separation and transfer system that reduces the exposure of a blood sample and provides fast mixing of a blood sample with a sample stabilizer. The biological fluid separation device is engageable with a blood testing device for closed transfer of a portion of the plasma portion from the biological fluid separation device to the blood testing device. The blood testing device is adapted to receive the plasma portion to analyze the blood sample and obtain test results.

A single unit bodily fluid collection and mixing device that is used for collecting a specified amount of bodily fluid, mixing the bodily fluid with a specified amount of solution, mixing the bodily fluid and solution in a contained volume to prevent contamination, and applying the resulting mixture to a lateral flow test surface. The unit is a single device, and does not require multiple pieces or systems to collect patient bodily fluid, measure out solution, combine the patient bodily fluid, and apply the mixture to a testing surface. Rather, the single unit already contains the desired amount of solution, a collection tube receives a specified amount of bodily fluid from a patient, and the single device can be used to mix the two fluids together.