JPH0450830B2 - - Google Patents

Abstract

For the freeze-drying of, in particular, biological or pharmaceutical material under sterile conditions, the material to be dried is placed in a container whose sides are at least partly composed of a hydrophobic, porous, germproof membrane which is permeable to water vapour, the container is closed pressure-tight and then the material is freeze-dried in the closed container under usual conditions.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a container for carrying out a freeze-drying process under aseptic conditions. The invention relates in particular to containers used for drying biological and/or pharmaceutical substances.

BACKGROUND OF THE INVENTION With biological and pharmaceutical substances, it is often necessary to store the substance completely dry until its use. Often these sensitive substances can only be used by lyophilization. In addition, in most cases these substances must remain completely free of microbial pathogens, both for reasons of microbial-induced degradation of biological substances and to prevent possible contagion during their use. It is necessary to maintain it.

Freeze-drying of biological and pharmaceutical substances is generally known (Ullmanns Enzyklopa¨die der
Technischen Chemie, 3rd edition, Volume 1, No. 556
(see following pages). In order to avoid contamination of the dried product with bacteria and other impurities, expensive equipment and process-technical measures are taken.

When drying pharmaceutical preparations in ampoules or bottles, for example, the bottle containing the frozen substance is equipped with a bacterial filter and the substance in this bottle is dried during the first drying step, which ends the sublimation of the frozen solvent. Dry until dry.

Subsequently, in a second drying step, the so-called after-drying or residual drying, any remaining residual moisture is removed from the material. This second drying step is usually carried out in special equipment, so that the ampoules or flasks are removed from the first drying device and introduced into the second drying device in another contamination-sensitive working step. For this purpose, the bacterial filter is removed and replaced by an aluminum cap with a rubber membrane plate and hollow needles. After several days of residual drying, depending on the type of material to be dried, the drying chamber is filled with inert gas and a slight overpressure and the membrane plate openings are sealed as vapor-tight as possible with casting material.

Freeze-drying of biological and pharmaceutical substances is also carried out on plates under aseptic conditions, since the sublimation rate in this type of freeze-drying is about half that of open, diffused materials. In this case, the solution of the substance to be dried is first sterilized, for example by filtering through a sterile filter, then poured onto plates under aseptic conditions and freeze-dried using known methods. This method, however, presupposes that the entire freeze-drying equipment is sterilizable. In addition to it,
It is necessary to keep the area around the drying equipment sterile.

After drying, the material is removed from the plate under aseptic conditions using mechanical methods on itself or around it in a drying device and is likewise filled into sterile storage containers. This method requires expensive equipment and sterile space and particularly careful handling of the material to be dried or already dried until its ready-to-use product.

Problems that the invention seeks to solve By the way, the present invention overcomes the above-mentioned drawbacks and provides a sterile, freeze-dried The objective is to provide an easy method by which the substance can be obtained.

Means for Solving the Problem This object is achieved by the invention by drying the substance to be dried.
Under sterile conditions, the bounding wall is at least partially germ-tight, pore size
into a germ-tightly sealable container consisting of a hydrophobic membrane permeable to water in vapor form with a porosity of 0.5 μm, and the container is sealed in a germ-tight and pressure-tight manner, in particular This is achieved by gluing or welding and freeze-drying the material directly in this closed container under normal conditions.

The invention unexpectedly provides that the vapor flow resulting from the sublimation of solvent molecules, especially water molecules, flowing from the material to be dried into the condenser, is reduced to a small extent by the membrane used in the process according to the invention. Based on the unexpected understanding that it is only hindered in scope. Surprisingly, therefore, freeze-drying of a material surrounded by a membrane proceeds at approximately the same rate as freeze-drying of the same open, unwrapped material. The membranes used according to the invention are, on the one hand, water vapor permeable and, on the other hand, hydrophobic membranes with pores so small that microorganisms can no longer pass through. Such pores preferably have a size of 0.5 μm, especially 0.2 μm. It is advantageous to use membranes according to the invention which are tear-resistant under the respective process conditions even in wet conditions. In any case, the process according to the invention can also be carried out with slightly more stable membranes, as long as they are reinforced with support materials or mechanically loaded not excessively.

The area of the membrane on the wall of the container used in each case selected in the method according to the invention depends on the conditions and drying time selected in each case and can be easily found by a person skilled in the art using simple tests. sell. In one advantageous embodiment according to the invention, the entire wall surface consists of this membrane sheet, and in another advantageous embodiment approximately up to half consists of this membrane sheet. Surprisingly, the method according to the invention can be carried out advantageously even if only up to 10% of the wall surface consists of membrane sheets.

Semipermeable papers made of cellulose and customary cellulose derivatives, such as cellulose acetate in particular, are suitable. It is particularly advantageous according to the invention to use membranes consisting of sheets of polymeric compounds such as polytetrafluoroethylene or polypropylene. Especially as a water vapor permeable membrane,
Also suitable are sheets of sterile paper according to DIN 58953. In another advantageous embodiment according to the invention, Goretex and similar membranes or Vihuri OY,
Trademark “Mediplast” from Wipack, Finnland
Use a commercially available regular sheet tube. In principle, each sheet membrane can be used independently of its components, provided that it fulfills the requirements stated in DIN-Standard 58953 with regard to sterility, air permeability and, in particular, strength.

In an advantageous embodiment, the method according to the invention consists of two walls that are tightly and pressure-tightly connected to each other, especially at their edges, one of which is made of a liquid-tight material and the other is made of a membrane. It is carried out using a bag or tube consisting of:

The membrane is preferably welded or glued to the container.
According to the invention, a container is particularly suitable as a container.

In another advantageous embodiment, the trough is made of liquid-tight plastic and has a wall thickness, in particular from 0.5 to 1 mm.

The most advantageous drying conditions, such as pressure, temperature and volume, depend in each case on the substance to be dried, the thickness of the membrane and the size and number of its pores, and the customary conditions for the respective material and packaging. and must be confirmed by a simple test.

The invention is illustrated in detail with reference to the following examples.

Example 1 The bactericidal tightness of a membrane is tested in accordance with DIN 58953 by placing microorganisms in a water droplet onto a test piece, and after drying the water droplet, testing whether the microorganisms have leached out to the underside of the test piece. carried out.

The membrane sheet to be tested was cut into squares approximately 50 mm square. The specimens were sterilized and dried. Place each specimen of sterile membrane onto the sterile base from above, with the side that could be contaminated during application, and
Five drops of up to 0.1 ml were inoculated (equivalent to 10 ⁶ to 10 ⁷ bacteria). The specimens were stored at room temperature of 20-25°C and under relative humidity of 40-60%. The drops must be completely dry within 6 hours. Each specimen was placed, inoculated side up, onto the surface of a blood agar plate (1.5% agar), where the entire sheet surface was in contact with the agar. 5
The paper was removed after ~6 seconds. This board was heated to 16-25℃ at 37℃.
The temperature was kept constant for hours. Agar plates treated with such sheet samples showed no growth, indicating that the sheets were sufficiently sterile. Further information on testing the sterility of membranes, in particular the production of test bacterial suspensions, can be found in DIN
- Listed in Standard 58953-6.

Example 2 Peptone 10g, glucose 5g, NaCl 5g,
A nutrient solution was prepared consisting of 0.084 g KH ₂ PO ₄ , 0.187 g Na ₂ -HPO ₄ ×2H ₂ O and pyrogen-free water added to 1.0 and adjusted to PH 7.0. This was then terminally sterilized in a sealed puncture bottle.

A transparent sterile bag consisting of a transparent sheet and a suitable paper was manufactured for receiving the sterile nutrient solution to be lyophilized. For this purpose, a hose-shaped, i.e. open but welded on both sides, is placed on a roll (roll width 400 mm).
Pieces were cut to a length of 800 mm from a commercially available transparent sterile bag sheet of type Seri-King R47 from WipakMedical. The hose is welded into a bag on both sides with commercially available sheeting equipment. The bag is then sterilized in an autoclave with a filter program at 123 °C and a steam pressure of 2 bar, and the sterile bag is placed in a non-sterile laminated container (VA-Blech. dimensions) with a transparent sheet underneath for better handling. :length
800mm, width 400mm, height 30mm) and Laminar-Flowbox.
It was opened by cutting off the corners with sterile scissors under aseptic conditions inside. From the approximately 30 mm opening between the sheet and the paper, fill 1.5 liters of sterile nutrient solution through a sterile hose pushed into the opening. The bags filled in this way were then sealed in a laminar flow box under aseptic conditions by welding the corners using commercially available sheet welding equipment.

All equipment (plate pails, bags and sterile nutrient solution)
−45°C in a commercial non-sterilizable freeze-drying apparatus from Edwards+Knises with a total layout area of 1.5 m ²
onto a pre-chilled plate and the solution was frozen. After complete freezing of the solution under non-sterile conditions, lyophilization was carried out at a pressure of 10 ⁻¹ mmHg and a plate temperature of 22° C., and the product was post-dried at 10 ⁻³ mmHg, also under non-sterile conditions. . Total drying time is approximately 72
It was time.

The lyophilizate thus obtained, present as a light brown powder in a transparent sterile bag, is brought into a laminar flow box including the bag and 1.5
Dissolved in sterile water. For this purpose, disinfect the prescribed puncture site on the paper side with alcohol and use a sterile cannula and a suitable sterile syringe for a total of 1.5
of sterile water into the bag to dissolve the dry matter and transfer the solution into a sterile bottle. This solution was kept at a constant temperature of 37° C. for 4 days, and the number of bacteria in the solution kept at a constant temperature was subsequently measured by a membrane filter method.

Freeze-drying showed that no bacteria were introduced.

Claims (1)

[Scope of Claims] 1. A container for freeze-drying biological or pharmaceutical substances under aseptic conditions, the sides of which are at least partially formed by two walls tightly and pressure-tightly interconnected at their edges. one wall is made of a liquid-tight material and the other wall is made of a hydrophobic, porous, germ-tight, water vapor permeable membrane, the pores of which
Container for freeze-drying biological or pharmaceutical substances, characterized in that it has a size of 0.5 μm. 2. The container according to claim 1, wherein the pores of the membrane have a size of 0.2 μm. 3. Container according to claim 1, wherein the membrane is a sheet having characteristics according to DIN 58953. 4. Container according to any one of claims 1 to 3, wherein the membrane consists of semipermeable paper, in particular of cellulose and cellulose derivatives. 5. A container according to claim 4, wherein the membrane consists of cellulose acetate. 6. Container according to claim 1, wherein the membrane is a sheet of a polymeric compound, in particular polytetrafluoroethylene or polypropylene. 7. Container according to any one of claims 1 to 6, wherein the container is configured as a tube or a bag. 8. Container according to claim 1, wherein the container is configured as a bottle, an ampoule or a flask, which is sealed with a membrane. 9. Claims 1 to 6, characterized in that the container is configured as a trough which is pressure-tightly connected to a membrane as a cover.
A container according to any one of the following items.