IL142819A - Capsule based drug delivery system - Google Patents

Description

A CAPSULE BASED DRUG DELIVERY SYSTEM BIOPROGRESS TECHNOLOGY INTERNATIONAL INCORPORATED A CAPSULE FOR DELIVERY SYSTEM field of the Invention This invention relates to soft capsules for delivery to The provision of soft capsules containing pharmaceutical preparations is well drugs and dietary supplements encapsulated in soft or gelatin shells designed release their contents under specific conditions enconniered in the The shells used fo these capsules derived animal renderings With concerns of related diseases such as Spongiform Encephalopathy and the existence roups of unable or unwilling to take animal based products for religious or ethical there is a profound for a substitute material for soft capsule the production of gelatin capsules does not lend itself to the use of alternative particularly those suitable for additio those materials perform in a similar fashion mechanically to gelatin do have suitable1 properties to spoilage of certain sensitive ingredie a necessary to change not only the capsule but also the machinery used for their It is this change in and the necessary processing means which this by providing soft capsules good barrier properties and controlled Summary of According to the invention there is provided a soft capsule comprising a wall from multilayer film of three namely a sealing of hydroxy methyl layer of propylene glycol alginate and a barrier layer of sodium The encapsulating films have robust properties and good oxygen barrier when used as a capsule The films created are preferably but not essentially coated achieve precise drug delivery protection their contents and use a carrier membrane which als as the sealing The sealing layer is typically a modified cellulose 18 to thick and soluble cold The coatings control the time site of release of the finished capsules as well as offering specific barrier properties to prevent the spoilage of the capsule The conversion process involves film vacuum sealing and materials used to coat the surface of the cellulose sealing layer include propylene glycol gellan xantham locus bean soy arid derivatives as Arainoxylan ferulyate and gum These materials can be applied to the surface either before the made or as a finishing treatment to pre The selection of the coating material is determined contents and release characteristics required of the finished In to provide flexibility materials can agents suc or mono propylene A to polymer ratio of has been found to impart good flexibility for capsule Where the agents are as a post treatment this plasticiser content can One or more of the three layers are preferably deformable by providing between them the means for sealing good These three layers function well over a wide of individual is selected according the type of capsule and end In a typical oil bearing soft capsule the carrier or sealing is hydroxy cellulose glycerine and propylene glycol or di or tri at a thickness of 10 to 150 the upper barrier layer sodium alginate at a thickness of 5 to 50 microns plasticised glycerine or achieve a good level adhesion between these layers a tie layer promoting adhesioii consisting of propylene glycol aTginate in the region of to 20 microns is It is preferred that the layer is by heat and seals using the established of radio a combination of high ultrasonic induction welding can be employed as the sealing Good results have been achieved using methyl propyl cellulose plasticised with glycerine and ropylene glycol at 100 microns as a layer with radio as sealing To secure a barrier layer sealing layer sufficiently well that it will survive the rigours the capsule process without delamination it has been found necessary and beneficial to use an or tie Propylene glycol alginate improves the adhesion of alginate to hydroxy propyl methyl as does a blend of propylene glycol alginate and propyl methyl The materials used in this tie layer may also be plasticised with such materials as glycerine and or propylene glycol at In this invention propylene glycol alginate has been round to perform this function at a thickness of The top layer provides the to obtain specific barrier properties as well as time and site release such as within the body the case of Time release can be but sod alginate or is used as layer it can be made partially soluble by introducing the surface to calcium ions thus forming a thin water insoluble layer which be made to the presence of sequestering agents or when there is a change in The multi layered capsule shell is prepared by coating the innermost sealing layer with ah adhesion layer and a barrier or controlling These can be applied Meyer fiexo The preparation of the multi layered can occur within capsule manufacturing unit or whereby the multi layered film is supplied to a dedicated be by application of tie layer barrier capsules formed exclusively the sealing Where this occurs as a post treatment by such methods as spray dusting or gum polyols and waxes have been found to work The ability to seal any of films described in this patent by heat inducing including and the ability to strong finished seals can be enhanced by the application of certain water soluble and to the surface of the sealing These materials also help to seal where the surface of sealing is with Propylene pvrrolidone and gamma have been t well in A preferred method of encapsulation is characterised by supplying a multi layered film to dedicated encapsulation unit capable of the into capsule sealing and the encapsulation film is pre formed preferably the use of vacuum into capsule halves and the encapsulated is supplied between the films where it enters the two pre halves The pre forming process may be enhanced by heating the fonning or film to an of order to minimise exposure of the capsule to high temperatures it is preferred that the film is heated just prior to capsul rather the capsule forming The typically consists of a pair of flat forming heads or where at least one of pair is formed with iMentatioiis capsule on Means for vacuum to these forming is conveniently to help pull the into the assist in capsule These heads are supplied by rolls of film which be with several applications before them The pre formed capsules are while inside the before sealed the application recognised and established namely radio frequency or combination of these After sealing capsules cut out Whilst it is preferred feature that the sealing and cutting occur at the same location it also occur as a process capsules formed and filled at a different location to they sealed and where they are The invention will further be by way of with reference to the accompanying in Figure 1 is a representation of a Figure is a schematic representation of the preferred film of a capsule according to the and Figure 3 a schematic illustration of a unit for making the SHEET Detailed Description of Figure 1 illustrates a capsule with a substance encapsulated by a shell wall The capsule shell membrane illustrated Figure 2 comprises three The seaiins 1 is hydroxy propyl methyl plasticised lycerine at and propylene glycol at present at 100 The top is a barrier la er and is sodium alginate plasticised with glycerine sorbitol at present at a thickness of 10 these layers 1 and 3 is an sealing layer helping and made of propylene glycol at a of 4 intermediate may also contain a plasticiser up to 50 The three layer wall or membrane is prepared by a series of two coatings from solution or by extrusion on to the of hydroxy propyl cellulose The propylene glycol alginate followed the plasticised sodium The coatings are separately by means of coating heads onto the surface of the hydroxy propyl methyl cellulose on conventional coating The three layer film can then be supplied to the encapsulation unit pre formed Figure 3 a capsule processing unit where the cutting process occurs remotely from fanning From the two top of Figure iengtns of film are fed to the forming female forming head and cutting are located in a with flat faces exampled by either side of the capsule areas by The female areas have raised side which help in the channelling excess liquid away from the As the cutting does not take place at the point of the female forming unit is not Film passes over the head 6 and the forming cylinder is applied to draw the film into the forming Forming head 6 has a cup 15 with a small groove cut in a grooved stripper plate The injector 5 comes down and then engulfed by the stripper plate groove 16 in stripper plate The injector 5 SHEET then withdraws as it fills the pre formed When the injector 5 has a forward motion by forming head 6 causes a seal to be This seal is completed by the action of radio frequency combination of these When the capsule is made filled the moves away the drum 8 and the drum present another farming The filled capsule which has not been cut remains held place in the head 6 means of capsule remains in the drum it is passed to cutting drum This occurs by of a loss in vacuum oh the formin shown by the shaded area and the presence of vacuum in the drum The formed capsule asses over the head where by means of a punch cut free from the The finished capsule 12 remains hi cutting drum 7 until it drops into the tray 13 when vacuum on the forming is released the area The waste with holes is transported via the rollers By using the multilayer film shown in Figure 2 in the apparatus of Figure good quality soft capsules were produced suitable SHEET insufficientOCRQuality

Claims (1)

1. CLAIMS A soft capsule comprising a wall derived a multilayer film comprising of three namely a sealing layer of hydroxy propyl methyl an promoting of propylene glycol and a barrier layer of sodium A soft capsule according to claim wherein the layer made from propyl methyl cellulose an A capsule according to wherein the sealing layer is sealed by means of radio ultrasonics or heat A soft capsule according to 1 wherein the sealing layer is sealed by means of A soft capsule according to claim 1 or wherein sealing of the is enhanced by application to the sealing layer of an A soft capsule to claim 1 or wherein sealing of the film is enhanced by application to the sealing layer of a A soft capsule according to 1 or wherein sealing of the film is enhanced by application to the sealing layer of a A soft capsule to claim 1 wherein sealing of the is enhanced by application to the sealing layer of a A soft according to claim 1 or wherein sealing of the film is enhanced by application to the layer of SHEET 9 A soft capsule accordiag to the material used to sealing is mono A soft capsule according to any of the preceding ths capsule is coated after formation SHEET insufficientOCRQuality