Cell or drug encapsulation device having a wet seal

Abstract

A biologically implantable containment device having a wet seal, the device being adaptable for drug formulations or cell suspensions. A porous membrane, in a tubular configuration, is formed and can be configured as part of a closed cell-tight system for loading. During loading, the containment device membrane is wet, while the loading system remains cell-tight. The containment device is wet-sealed through a combination of heat and pressure, while the system remains cell-tight. Sealing the containment device substantially or completely eliminates metabolic functioning of any organisms in the vicinity of the closure. The wet-seal is formed by melting a thermoplastic material that is in contact with the membrane. The containment device is separated from the cell-tight loading system, which remains closed after separation.

Description

CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation of co-pending application Ser. No. 10 / 462,915, which is a division of application Ser. No. 09 / 515,264 filed Feb. 29, 2000, now U.S. Pat. No. 6,617,151.BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The invention relates to the field of implantable devices and more particularly to devices that are wet-sealed. [0004] 2. Background Information [0005] Within the field of implantable devices, it is known to provide permeable membrane structures for implantation, the structures configured to hold drug formulations or cellular suspensions. A number of techniques have been proposed to form those structures and seal the structures. In the majority of those known techniques, the device is manufactured without the cellular suspension or drug formulation. Subsequent loading of the cellular suspension or drug formulation may occur outside a host or after the device is implanted into the host. W...

AI Technical Summary

Benefits of technology

[0019] In one aspect, the present invention provides a method of loading a containment device comprising creating a closed cell-tight system, the system including the containment device and a source of metabolically active cells. Loading a containment region of the device with the metabolically active cells vi

Problems solved by technology

Given the nature of the membranes, it is known that sealing a wet membrane can be difficult or impossible.

This is because known glues and solvents that are appropriate for membranes in a dry state are frequently not compatible with a wet membrane, or are toxic to cell suspensions loaded into the membrane structure.

With implantable devices, the mechanical seal dimensions are small and can be difficult to reliably manipulate.

In addition, because the loading and sealing operations can be distinct, there is an opportunity for contamination of the device exterior with cells from the cell suspension after the loading operation.

The solvents described may be toxic to the cell suspension, however.

This action presents a strong possibility of contaminating the loading environment.

In addition to problems that are described with wet sealing of the device, this technique is performed through an incision or injection port following implantation in the host, thereby exposing the device and the host to a risk of contamination.

This larger device also produces greater host trauma during implantation.

In these methods, the loading process or apparatus provides opportunities for contamination from drug formulations or cell suspensions between the loading and the sealing steps.

As described, the methods available do not provide a secure and reliable closure system, that reduces the possibility of contamination during loading.

In addition, the methods available do not provide a method to reliably seal a device after the membrane is wet.

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