Abstract: Molecular adsorption to the microfluidic device surfaces can be passively and actively mitigated by mixing certain hydrophilic polymers (organic polymers with repeating hydrophilic groups—the preferred polymers being amphipathic surfactants—with the sample liquid during or prior to relevant microfluidic operations. Nonionic surfactants such as polyoxyethylene sorbitan monooleate and polyoxyethylene octyl phenyl ether are especially effective. High molecular weight polyethylene polymers are also effective. The hydrophilic polymers appear to prevent binding of the fouling molecules to the microfluidic by occupying the surface sites in place of the fouling molecules or by interacting with the fouling molecules to prevent binding of the fouling molecules the surface. When surface adsorption is thus mitigated, microfluidic devices can readily handle samples containing biomolecules to enable active sample concentration, filtering, washing, transport, mixing and other sample handling operations.

Abstract: An subcutaneously implantable device for delivering Risperidone to a patient includes a pump, a compartment configured to store a pharmaceutical formulation, and a volume of the pharmaceutical formulation loaded in the compartment, the pharmaceutical formulation including Risperidone solvated or suspended in a pharmaceutically acceptable solvent in concentration of at least 50 milligrams per milliliter. The implanted pump may then deliver a therapeutically effective dose of Risperidone to the patient.

Abstract: A pump, includes a pump engine; a compartment adapted to store a fluid, the compartment being disposed at least partially around the pump engine, and a piston disposed within the compartment, the compartment and the engine being configured to cause the piston to travel within the compartment along an arcuate path and to force a volume of the fluid out of the pump.

Abstract: Implantable devices and osmotic pump and catheter systems for delivering a pharmaceutical agent to a patient at selectable rates include an impermeable pump housing and a moveable partition disposed within the housing, the partition dividing the housing into an osmotic driving compartment having an open end and a pharmaceutical agent compartment having a delivery orifice. A plurality of semi permeable membranes may be disposed in the open end of the osmotic driving compartment and a number of impermeable barriers may seal selected ones of the plurality of semi permeable membranes from the patient until breached. Breaching one or more of the impermeable barriers increases the surface area of semi permeable membrane exposed to the patient and controllably increases the delivery rate of the pharmaceutical agent through the delivery orifice and catheter.

Abstract: An implantable pump for delivering a pharmaceutical agent includes a pump engine, a piston, a pharmaceutical agent compartment and a rate adjustment assembly. The pharmaceutical agent compartment is configured to enclose a volume of pharmaceutical agent and the piston. When the piston is acted upon by the pump engine, the piston moves within the pharmaceutical agent compartment along a substantially circular path and delivers the pharmaceutical agent. The rate adjustment assembly is configured to enable a selective and reversible increase or decrease of the delivery rate of the pharmaceutical agent.

Abstract: An implantable osmotic pump for delivering a pharmaceutical agent to a patient includes an osmotic engine, a substantially toroidal compartment disposed at least partially around the osmotic engine and a piston disposed within the compartment. The osmotic engine is configured to cause the piston to travel within the compartment and deliver a dose pharmaceutical agent contained within the compartment when the pump is implanted in an aqueous environment. A dose escalation assembly may be fitted to the pump, the dose escalation assembly being adapted to selectively increase the rate at which the pharmaceutical agent is delivered from the pump.

Abstract: An implantable osmotic pump system includes a pre-hydrated semipermeable membrane to reduce the time interval between implantation of the system into the patient and full operation of the pump system. The semipermeable membrane is maintained in a hydrated state prior to implantation by fluid contact with a saline solution maintained in a saturated state by a salt tablet. As the differential osmotic pressure across the hydrated semipermeable membrane is negligible as the saline concentration on both sides of the membrane is the same, the pump system does not operate and does not infuse the pharmaceutical agent as long as this osmotic equipotential state is maintained. When the saturated saline solution is removed from fluid contact with the semipermeable membrane and the system is implanted in a patient, the osmotic pressure differential across the semipermeable membrane increases, thereby causing the pump to immediately begin operation at or near its intended and designed steady state infusion rate.

Abstract: An implantable osmotic pump for delivering a pharmaceutical agent to a patient includes an osmotic engine, a substantially toroidal compartment disposed at least partially around the osmotic engine and a piston disposed within the compartment. The osmotic engine is configured to cause the piston to travel within the compartment and deliver a dose pharmaceutical agent contained within the compartment when the pump is implanted in an aqueous environment. A dose escalation assembly may be fitted to the pump, the dose escalation assembly being adapted to selectively increase the rate at which the pharmaceutical agent is delivered from the pump.

Abstract: Implantable osmotic pump devices and systems include multiple osmotic pumps and/or semipermeable membranes to extend the useful life cycle and functionality of the drug delivery system. Use of an implantable system including multiple implantable osmotic pumps allows different drugs to be administered from the same implanted system. One or more of the semipermeable membranes of the system may be initially sealed by an overlying impermeable membrane upon implantation of the system into the patient. When the patient develops a tolerance to a first drug or to a first dose of the first drug, the impermeable membrane may be breached, to expose the underlying semipermeable membrane to the osmotic pressure of the patient at the implant site. This causes the infusion rate to increase, thereby providing the patient with the needed relief and/or other desired therapeutic effect. In the case of a multiple pump system, breaching an impermeable membrane may cause the infusion of a second drug.

Abstract: Implantable osmotic pump devices and systems include multiple osmotic pumps and/or semipermeable membranes to extend the useful life cycle and functionality of the drug delivery system. Use of an implantable system including multiple implantable osmotic pumps allows different drugs to be administered from the same implanted system. One or more of the semipermeable membranes of the system may be initially sealed by an overlying impermeable membrane upon implantation of the system into the patient. When the patient develops a tolerance to a first drug or to a first dose of the first drug, the impermeable membrane may be breached, to expose the underlying semipermeable membrane to the osmotic pressure of the patient at the implant site. This causes the infusion rate to increase, thereby providing the patient with the needed relief and/or other desired therapeutic effect. In the case of a multiple pump system, breaching an impermeable membrane may cause the infusion of a second drug.

Abstract: An implantable osmotic pump system includes a rigid pump housing defining an opening adapted to receive a catheter; one or more membrane assemblies fitted to the pump housing; an osmotic engine within the rigid pump housing and a flexible pharmaceutical agent compartment disposed within the pump housing. The flexible pharmaceutical agent compartment is adapted to enclose a volume of a pharmaceutical agent and to cause the pharmaceutical agent to be infused through the opening as water crosses the membrane assembly or assemblies and increases the volume of the osmotic engine. The flexible pharmaceutical agent compartment may include polyethylene teraphthalate (PET), for example, and/or may include a metallic layer such as gold, silver, platinum and/or aluminum, for example, to inhibit the transfer of gas or liquid across the compartment. A catheter may be bonded to the opening of the pump housing and to a corresponding opening in the flexible pharmaceutical agent compartment.

Abstract: Implantable devices and osmotic pump and catheter systems for delivering a pharmaceutical agent to a patient at selectable rates include an impermeable pump housing and a moveable partition disposed within the housing, the partition dividing the housing into an osmotic driving compartment having an open end and a pharmaceutical agent compartment having a delivery orifice. A plurality of semi permeable membranes may be disposed in the open end of the osmotic driving compartment and a number of impermeable barriers may seal selected ones of the plurality of semi permeable membranes from the patient until breached. Breaching one or more of the impermeable barriers increases the surface area of semi permeable membrane exposed to the patient and controllably increases the delivery rate of the pharmaceutical agent through the delivery orifice and catheter.