A blood cartridge device comprising: a removable cover; and a main body coupled with the removable cover, the main body comprising: a measuring chamber; a mixing chamber retaining one or more dissolvable reagent beads in position, the mixing chamber comprising: a plurality of walls formed by the removable cover and the main body; an entrance, the mixing chamber in fluidic connection with the measuring chamber through the entrance; and a blood guide extending outward from the wall of the blood cartridge device, the blood guide oriented within the mixing chamber for directing flow of blood to a first type of the one or more dissolvable reagent bead located directly below a leak barrier such that the blood contacts the first type of the one or more dissolvable reagent beads first before contacting other reagent beads in the mixing chamber; and the leak barrier comprising an indentation into one of the plurality of walls of the mixing chamber, formed by the removable cover and the main body, the leak barrier positioned near the entrance of the mixing chamber and oriented across a flow direction from the measuring chamber into a side of the mixing chamber, the leak barrier configured to stop undesired leakage of blood from the measuring chamber to the mixing chamber. a removable cover; and a main body coupled with the removable cover, the main body comprising: a measuring chamber; a mixing chamber retaining one or more dissolvable reagent beads in position, the mixing chamber comprising: a plurality of walls formed by the removable cover and the main body; an entrance, the mixing chamber in fluidic connection with the measuring chamber through the entrance; and a blood guide extending outward from the wall of the blood cartridge device, the blood guide oriented within the mixing chamber for directing flow of blood to a first type of the one or more dissolvable reagent bead located directly below a leak barrier such that the blood contacts the first type of the one or more dissolvable reagent beads first before contacting other reagent beads in the mixing chamber; and the leak barrier comprising an indentation into one of the plurality of walls of the mixing chamber, formed by the removable cover and the main body, the leak barrier positioned near the entrance of the mixing chamber and oriented across a flow direction from the measuring chamber into a side of the mixing chamber, the leak barrier configured to stop undesired leakage of blood from the measuring chamber to the mixing chamber. a measuring chamber; a mixing chamber retaining one or more dissolvable reagent beads in position, the mixing chamber comprising: a plurality of walls formed by the removable cover and the main body; an entrance, the mixing chamber in fluidic connection with the measuring chamber through the entrance; and a blood guide extending outward from the wall of the blood cartridge device, the blood guide oriented within the mixing chamber for directing flow of blood to a first type of the one or more dissolvable reagent bead located directly below a leak barrier such that the blood contacts the first type of the one or more dissolvable reagent beads first before contacting other reagent beads in the mixing chamber; and a plurality of walls formed by the removable cover and the main body; an entrance, the mixing chamber in fluidic connection with the measuring chamber through the entrance; and a blood guide extending outward from the wall of the blood cartridge device, the blood guide oriented within the mixing chamber for directing flow of blood to a first type of the one or more dissolvable reagent bead located directly below a leak barrier such that the blood contacts the first type of the one or more dissolvable reagent beads first before contacting other reagent beads in the mixing chamber; and the leak barrier comprising an indentation into one of the plurality of walls of the mixing chamber, formed by the removable cover and the main body, the leak barrier positioned near the entrance of the mixing chamber and oriented across a flow direction from the measuring chamber into a side of the mixing chamber, the leak barrier configured to stop undesired leakage of blood from the measuring chamber to the mixing chamber.