1 PATE ~ 7UPP~ICA~IO~
8TIC APP~UURT~ FOR DB~IV~ING 8~nT2~N~
I2rrO CE~L~ 7~nD TI8B~E8 RP~T.~Il'~n aPPT.TCP.TION
Applicant~ claim priority bQnefits of provisional S applicat~on 60/059771 filed September 23, 1997 under 35 USC
ll9(e) BACKGRO~NP OF T~ L~ ON
The present invention i~ directed to a biolistic device for accelerating mî~ro-projectiles into intact cellsi or tissue6. More specifîcally, the pre~ent invention is airected to a biolistic devîce having a ga~ shock gen~rator ~or applying a gas 6hoc~ to a ~ixed carrier mRmbrane to di~end the membrane and separate micro-projectile~ from the sur~ce of the membrane at high ~ipeeds into th~ target cell~ or tissue~: ~
For medical application~, a biolistic ~evice muGt hAve ~everal characteristics including sa~ety, r~producibility, ease of use, n~n-trauma for the pat~ent and -;ni ~1 injury to the bombarded tissue. At the same time, maximum partiale dispersion, maximum particle velocity ~nd ~ 1 skin pene~ration are nee~ed. Existing bioli~ic devices need 1s lmprovement in ter~ of aelivery~ Rfficacy, reproducibility, gentleness and ease o~ u~e. Many o~ the prior art de~ice~
make a loud nois~ which can be frightening and impact ~he s~n ; ' ' , . ~ ,,.' . . . _ ~; . : i!'-,"
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2 P~TENT ~ P~ICATIO~
With a violerlt ~;hock wave o~ helium ga~;. Prior art configuration~; utilizinS~ a "flying disk" has ~:hot to ~;hot variation and ~ubj ect~ the ~kin to a viol~nt ghock wave and ~oes not achieve as much dispersal or penetration as might be de~ired.
~UMM~RY OF T~E T~V~N~ION
The present inv~ntion provid~s a new and impr~ed biolistic ~pparatus for injecting particles into cell~ and ti~sue~ whi~h i~ extrQmely ~afe, ea~y to use, highly reproducible, makes es~entially no noise, i~ painle~ and cause~ minimal trauma to the bombarded ~kin~
~he device according to the present i~vention ha6 ~een shown to re~ult in better particle di~pe~al, deeper ~kin penetration and h~gher sub~equent biolog~cal activitie~.
The pre~ent invention provide~ a new and improved bioli~tic device which effectively but gently accelerates micro-pro~ectiles into intact cell~ or ti~ues ~uch a~ ~kin compris~ng a gas shock generator, a fixed malleable membrane between the gas shock and the targ~t, a ~hap~d ~topping BUrface dispo~ed betw~3en thQ fix~3d m-3mbran~ and the target for controlled decslQrzltion of the di~tending membrane ana aper~ures in the ~topping ~urface which allow the tran~port of high 6peed micro-pro~ectile~ from the surface of the fi~ed membrane into the target.
The presen~ in~ention provides a new and improvea bioli~tic device ~or acceleratlng micro-projectiles into 3 PA~E ~ APP~I ~ TION
intact cell8 or ti~ue~ wh~ch utilize~ a gas shock generator comprised o~ a plurality of bur~t membrane~ which are clampea together upon ini~ial ~pplication of p~es~ure and w$11 ~ubstantially, simultan~o~sly burst when the pre66ure appl~ed thereto reach~s a predetermined value ~hereby relea6ing the ga~ under pressure ~ub~antially instantaneously to create a ~hock wavQ for contacting a carrier membrane and impaling the mic~o-particles thereon into a target~
The pre~ent invention pro~ides ~ new ana improved bioli~tic device for accelerating micro-pro~ectiles into i~tact cells or ti~sue~ compri~ing a ga~ ~hock generator including a ~agnetically controlled valve which i6 held ~:hut by magnetic force until pres~ure being applied thereto i~
~uf~icient to ~reak the magnetic ~eal at which point the magnetic seal suddenly collapse~ and the ~alve open~ whereby a ~hock wave is projected again~t a de~ormable carrier membrane to impel th~ micro-par~icle~ thereon into the cell~
or ti6~ue~.
The above and other object~, ~eatur~s and advantages of the pre~ent invention will be more apparent and more readily appreclated ~rom the following detailed de~cription o~
pre~erred ex~mplary embodiment o~ th~ pre~ent invention, taken in connection with t~e accompanying drawingG.
~IEF DE8CRIPTTON ~F ~B DRAUING~
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~ PA~ ~ A~PLIC~TIO~
Fig. 1 is a 3ide el~3vation view of a bioliE;tic devic~3, partly in section and partly brokQn away, for accelerating m~cro-projectiles into intact cells or tis~ues.
Fig. 2 i~ a sectional vlew of thQ houqing of the device S 6hown in ~ig. 1.
Fig. 3 i~ a sectiona~ vie.w of the piston assembly which exterld~: through said housing in concentric relation thereto.
Fig. 4 is a sectional vi~w o~ the nozzle body as s~own in Fig~ 1.
Fig~ 5 is a sectional vi~w of the coupler ~hown in Fig.
1 between the bursti~le membranes and the carrier membrane with ga~ flow pa~ages shown in phantom llne~.
Fig. 6 i~; a rear end view of the coupler ~hown in Fig. 5.
Fig. 7 i~ a front end vlew of the coupler shown in Fig.
5.
Fig. 8 is a sectional ViQW of a supporting ring ~or the coupler a~ ~hown in Pig. 1.
Fig. 9 i~ a front end view of the support ring as ~ho~m in Fig. 8.
Fig. 10 is an ena view o~ a ~upport ring for ~upporting the forward end of the piston as~embly.
Fig. ~1 is a side elevation vi~w of the 6upport ring shown in Fig. 10.
Fig. 12 i~ a 6ectional view o~ the nozzle outlet plate as shown in Fig. 1.
Fig. 13 i~ a rear elevational view the~eof.
!'., . : . , -PATEN~ APPLICATION
E'~g. 14 i8 a :~ront elsvational view thereof~. --Fig. 15 i~ a sectional view of the retaining ring ~ecursd in the opposite end o~ the hou~ing ~rom the nozzle body Fig. 16 is a rear elevational view thereof.
Fig. 17 i~ a ~ront elevational view ther~of.
~ig. 18 is a sec~ional view of the pres~ure ch. ~r securea to the retainer rlng at the rear end of the housing.
Fig. 19 ~ a rear elQvational view ther~of.
Fig. 20 is a front elevational view th~reof.
Fig~ 21 is a s~ctional view of the end cap ~ecured to the pres~ure cham~er member.
~ig. 22 iG a rear elevational view ther~of.
~ig. 23 i~ a front ele~ational ~iew th~r~of.
Fig. 24 i~ a ~ectional view of a magn~tica;ly con~olled ga~ pre~sure valvQ according to a ~econd embodiment of the invention.
DET~TT.~D D~CR~PTIQN OF TEE l~v~lON
The app~ratus of the pre~ent invention i~ shown in a~6embled form in Figure 1 and i~; compriged o~ a hollow, cylindr~cal housing 20 having internal threads 22 and 24 at opposite ends thereof. An ~longated plE:ton as~embly Z6 is mounted ln ~he hollow, cylindrical housing 20 concentrically thereo~. The piston assembly 26 i8 ~upport~d at it~ forw~rd end ~ mean~ o~ an annular member 28 (Fig. 10~ di~po~d 1n threaded engagement ~ith the thread~ 24 of the hou6ing. The annular ~e~ber ~8 is provided with a plurality o~ radially, 6 PA~E ~ ~ ~lCA~ION
inwardly directed projection~ 30 having ~nner end~ 32 di~po~ed on a circle having a diameter equal to the diameter of the p~e~ure chamber 34 at the forward end o~ the pi~ton a~embly.
A plurality of cut out portion~ 36 are located between each S pro;ection 30 to provide communication between the ahnular chamber 38 located between the pi~ton a~sembly 26 and thQ
hou~ing ~0 and the interior o~ the nozzle a~sembly 40.
The nozzle as~embly 40 (~ig~. 4-9 and 14) i~ comprised of a nozzle ~ody 42 having an externally threaded hub portion 44 di~po~ed in threaded engagement with the thread6 24 ~t the forward end o~ the housing 20. The oppo~te end of the nozzle body 42 is provided with a circular opening 46 which rec~ives a nozzls outlet plate 48. ~he nozzle outlet plate 48 i8 pro~ided with a larger diameter flange portion 50 adapted to engag~ the internal ~urface of an annular ~lang~ 52 formed on the nozzlQ body 4z. A smaller diameter central portion 54 having a plurality of through passages 56 is located within the opening 46 in the end of th~ nozzle body 42. An O ri~g 58 18 disposed in a groove on the internal fac~ of the flange ~2 to eeal the nozzle outle~ plate to the nozzle body 4Z. The internal ~:urface of the nozzle outle~ plate 48 i8 prov~ded with a recess 60 and the flange 50 i~ provided with four groo~e~ 62 equally ~paced apart.
An annular coupler 64 i~ mounted in the no~zle body ad~acent the nozzle o~let plate 48 by mean~ of an annular ring 66 c~f delrin material. The ~orward end of the ~;u~port , ~: , . ~ ' - , ' .. r ~ ' .
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7 ~T~ ~ ~iePLICATION
ring 66 is provid~d with ~our axially extending flange portion~ 68 ~guall~ spac~d about the circumference of the ring to de~ine gap~ 70 therebetween. The forward end of the coupler 64 is provided with a recQ~ 72 ha~ing a trape~oidal cros~ ~ection with the ~maller base ~f the trapezoid ha~ing a diameter equal to the diameter of the axially extending central passage 76 of the coupler 64. A plurality of axially ext~ndi~g bores 74 are equally ~paced about the central pasgage 76 to provide communication between the rece~s 72 and the rearward ~urface of the eoupler.
The rearward ~urface 78 of the coupler is provided wi~h an enlarged rec~3~3s 80 which i5 concentric with the axial bore 76 ~xtending through the coupler. The pres~ure chamber 34 of the plston assembly 26 i~ provided wi~h a forwardly ext~n~ng flange 82 with an annular crown 84 on the fo~ward end thereof.
The flange 82 is dimens~oned to clo~ely ~it within the reces~
80 in the coupler membe~. The pressure chamber portion 34 is provided with a ~ub~antially hemispherical pre sure chamber 86 which merge~ into a cyl~ndrical pasgage 88 extending through the flange 82 and having a diameter idQntical to the diameter of th~ bore 76 extending through the coupler 64. A
plurality o~ kapton membranes 90 having an ex~ernal diameter ~ub~tantially ~ual to the diameter o~ the recess 80 in the coupler, are disposed in the recess 80 for engagement by ~he Z5 crown 84 on thQ forward end o~ the flange S2 on the pre~sure ch~ ~cr member 34. ~he n~mber o~ membrane~ 90 may vary ~ ~aT~NT ~PPLICATIO~
depending upon thQ d~sired strength sinc~ the plurality of mem}~ran~s ar~ ad~pted to bur~;t ~rhen the desired pre~;sure i6 rsachea in the pres6ure chamber 86. A sinyle ~tronger carrier membrane 92 having a diamet~r e~ual to the diam~t~r of the nozzle outlet plate flange S0 is disposed between the ~lange ~ 50 and the coupler with ~ufficient play ~o allow co~munication between the through pas~agQs ~6~ ths rece-~sed portion 60, the rRcessea portion 7~ and the annular chamber 38 in the ab~ence of pre~surQ being applie~ to the membrane 92 in the forward direct1on.
Th~ piston assembly ~6 ha~ an axially extending bore 96 e~tending the ~ull length of the piston as~embly i~
communication with the pres~;ure ~h~ h~t~ 86 and a cylindrical reces~ 98 at ~he oppo~ite end thereof. ~he piston assembly 26 i~ provided with a cylindrical hub portion 100 ha~ing ~ larger diameter than the elongated body 102 o~ the pis~on assQmbly.
At the end of the pi~ton assembly, an enlarged flange l04 i~
provided adjac~nt the hub portion 100.
Adjacent the rRarward end of the housing 20, a retaining ring 106 having es~ternal thread6 108 thereon, i8 threaded into - Qngagement w~ th the int~rnal thread~ 22 of the housing 20.
The retaining ring 106 is provided with an axially extending rece~;E: 110 at thl3 forwar~ ena thereof having a plurallty c~f rad~ally directed passages 112 extending ou~war~ly to the threads }08. The retaining ring 106 is al30 pro~ided with a reduced diametPr bore 114 in which the hub portion 100 of the : !
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9 PATE ~ ~ PLICATION
piston as3embly 26 i~ ~lidably mounted. A pre~ure chamber memb~r 120 is provided with a forwardly ex~n~ing recess 122 having an int:-3rnally threaded portion 124 which i6 threaded onto the external thread~ o~ the retaining ring 106. The enlarged diame~er end portion 104 of the pi~ton asse~bly 26 i~
disposed in a reces~ 123 in the rearward portion of th~
retaining ring 1-6 and is ~xposed to pr~urQ in the reces~
122 o~ the pressure chamb~r m~mber. Th~ preggure chamber m~mber 120 is al~o provided with a plurality o~ ~hrough bor~
126 disposed adjacent the periphery o~ the pres~re member lZ0. A central ~ore 128 is prov~de~ for ln~r~duclng pres~ure into the pre~ure chamber and a plurality of threaded pa~ages 130 are provided about the central bore ~28 for the reception of connecting member~.
An end cap 140 is ~cur~d to the rQarward end of ~he pres~ure chamber member 120 by mean~ o~ cap scrQws (not shown) extending through three bore~ 142 wh~ch are in alignment with the threade~ pa~gages 130 in the prsssure chamber member. The rear end of the end cap i~ pro~ided with an ~xt~rnally threaaed nozzle 144 which is adapted to be connected to a ~uitable vacuum gource and a high prQ~Ure helium ~ource (not shown) The end cap i~ provid~d with a rece~s 146 ~n the forward end thereof ha~ing ~ tr~pezoidal cro~ section with the rece~ in ~v lnication with the inlet passage 148 ext~n~ng through the nozzle 144.
':" ' , ' ' ' . ~' ', ' . ' 10 PATENrr ~ PLIC~IO~
In the operation o~ the app~rat~ according to the present inv~ntion, th~i forward end o~ ~he nozzle body 40 i~
pres~ed again~t the ti~su~ to be inoculated with particleis 6uch as genetic material~ Since th~ foxward ~urface of ~he r~ozzle outlet plate 54 i8 recesssd rQl~tiv~ to thR nozzle body as be~t ~een in FigurQ 1, a thin chamber is formed in communication with the pa~age~ 56 through which th~ particles are ejected. A vacuum i~ applied to th~ ~ntir~ assQmbly by connecting t~e nozzle 144 to a ~uitabl~ vacuu~ ~ource through valve m~ans ~not ~hown). 'rhe vacuum i8 applied through the axial pa!3sagQ 148 of the nozzle 144, the rec~ 8 146 in the ~sind cap and the annular cbamber 38 by means o~ the connecting pa~sage~ 126. Th~ vacuum i~ al~o applied ~o the passag~s ~6 in the outlet pl~te 54 as well a~ the outèr surSac~ of the outlet plate 54 through the reces~ 60 in the outlet plate 4~, the pa~sage~ 74 ext~nding through the coupler 64 to the annular chamber 38 through the opsnings 36 in the annular support membQr 28, 5ince the carrier membranQ 92 is mounted ' ~th ~uf~icient play, it is po~ible for the vacuum to be applied around the periphery of the carrier membran~ through the grooves 62 in the flange of th~ ou~let plate. By applying the vacuum to the system, the atmospheric ~a~ses, as ~ell a~
any residual heli~m ~e~ ~rom a pr~vioug usage, a~e removed fxom the vacuum body a~ well as remo~ing any stray gas from the high ~res~ure chamber and the line~ ~upplying the accelerator. Thus, dur~ng a ~ubsequent Q~ ~ction opeiration, ''" '~1''' ' ~
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11 ~A~E ~ ~ PLIC~TIO~
only helium ga~ will be in the high pre~sure Gha~ber 86 rather than the u6ual mix of a~r and helium gas.
A~t~3r sufJ~icient vac~um ~ introduced, a vac~ ;en60r (not 6ho~n) will initiate the introduction o~ prQs~urized hellum ga~ through the nozzle 144~ The pre~surized heli~m ga~
will act on the enlarged end portion 104 of the pi~ton assembly 26 to ~hift the pi~ton a~embly 26 axially to brlng the crown 84 on the flange 82 of the pi~ton ~6emb1y 26 in~o clamping engagement with ~he bur~t membrane~ go by clamping the burst membranes 90 a~ain~t the bottom of the enlarged r~cess 80 in t~e rear ~ur$ace o~ the ~ouple~. The pressurized h~lium gas will also enter through the rece~6 98 in the rearward end of the pi6ton a6~e~bly ana the elongated through p~ssage 26 to the pre~6ure chamber 86. The pre~ure will ramp up in t~s high pressure chamber 86 un~11 it reache~ the yield pre~sure o~ the burst membrane~ 90. The membrane system can consist of ~ny d~ired number of membranes~ For example, the mem~rane ~ystem may con~ist of ~.0~2" (2 mil) kapton membran ~r di6k~. Each disk would have a bur~t pre~sure of approximately 400 psi. ~s the pre~ure reache~ the yield point of the kapton group, one of the membranes will bur~t, rapidly followed by the ~:econd, third and fourth. ~heln the ~ourth membrane y~eld~, t~e pressure against it i~ ~our times itQ burst point.
The ga~ chamb~r or high pre~u~e chamber 86 is designed l:o allow an energy ef~icient gas front to reach the captivated , ' ~ ;' ! , . ~; ' ,'i, !, !, . ~ , 12 ~ATE~r lLPP~IC~hTIO~
membr~ne. The gas chamber i~ de~igned with a l~ngth to width (aspect ratio) of approximately 1:1. The spherical rear ~hape of the high pre~ure chamber recover~ some of the energy lo~t when the membranes initially yield. The length o~ the chamber is optimized to create the most efficiQnt pressure front with the leas~ amount o~ exces~ ga~. ~hi~ allows a smaller vacuum body to be de~igned, a6 le~ total volume ~f helium gas has to be controlled. A~ the pre~ure front advance~, it accelerates th~ captive carrier membrane which i~ al~o made of kapton material. The carrisr membr~ne 1~ hal~ed abruptly as it ~tops again~t the flange o~ the outlet plate an~ clo~e~ tho grooves 62. The p~rticle~ adhered to th~ ~ur~ac~ o~ the carrier membranes, ~uch as generlc material, leave thQ carri~r membrane a~ it ~uddenly de~orms into the rece~ 60 and fly through the hole~ in the ~topping plate to enter the target t:i~8u~. ~he rece~;f3 60 in the nozzlQ outlet plate 48 allow~
the carrîer membrane to deform outwardly without ruptur~ng.
However, under c:~rtain circum~tances, it may be desirable to have the carrier membrane also rupture.
By contai~ing the carrier membranQ in tact, the ~orce of the ga~: bla~ will not reach the tis~3uQ, thQreby eliminati~g pre~3sure tr~uma to the t~su~. Force o~ the high pr~3s!3ure helium can be dissipated rearwardly through the pa~sages 74 in the coupler into the large annular chamber 38, which i~ ~till und~r vacuum.
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CA 02248622 l998-09-23 13 ~AT~ ~ APPLICA~IO~
T~e actual ~light di~tance of the carrier menibrane i~
reduced fro~n many centimeter~ in prior art ~;tructure~: to far lesG than one centinleter and the target i~: di~po~;ed in substantially inti~ate contact with the ~topping plate. The carrier m~mbrane so act~ a~ a one way valve ina~much a~
previou~ly allowed a vacuum to be introduc~d to the target but which is ~eale~ aga~n~t the outlet plate to prevent the gas front from getting ~n front of the carrier membrane and di~rupting the fligh~ characteri~tice of the genetic materia~.
Accor~ing to a second embodiment of the pre~ent invention, a magnetically controlled v~lve may ~e u~ili2ed ln lieu of the rupturablQ membrane~ of the f ir~ embodiment whereby repeatabi~ity can be enhanced without the need ~or replacing the ruptured me~brane~. The valve, as shown in Pig.
24, would ~till b~ used with the carrier membrane as ~hown in the previous embo~i ~nt.
A housing lS0 is provided with a rece~s having a valve body 152 secured therein by mea~s of a threaded connection 154. Th~ valve body 152 i~ provid~d with a valve opening 156 having an annular valve ~eat 158 extending outwardly from a valve chamber 160 def~ned between the housing and the valve bc ~ly . A neodymium magnet 162 is moun~ed in a rece~ in the hous~ng 150 with a ma~or ~urface th~reo~ expo~ed to the interior o~ the valve chamber 160. An iron or ~teel plunger 164 is mounted in ~he val~e chamber 160 and is provided with a E;tem 168 which extends through the valve opening lS6 and is 1~ PATE~rr ~ PLIC~ O~
provided with an enlarged head 166~ An O rlng 170 having a diamet~r equal to the diameter of the valve seat 158 is mounted in a groove 172 having a trapezoidal cro~6 section to as~i~t in ret~ining the 0 ring within the groove under E:tre~6~ul condition6.
In operation, the plunger i6 dratm int:o engagement:~rith the magnet, whereby the o ring will be moved into ~ealing engaqement with the valve ~eat. High pre~ure ga~ i~
introduced into the valve c~amber through a g~G line 17Z. The high pressure ga~ ~ill~ the valv~ chamber 160 in contact with opposite ~urface~ of the main body of the plunger and upon reaching a pred~termined pre~ure, wit~ cause ~e p~unqeL t~
separat~ from the magnet. Once the plunger leave~ contact with the magnet, the holding force will be substantially reduced and the plunger will move do~nwardly a~ viewed in Fig.
Z4 to relea~e the gas within th~ ch~ ~r with an explosive force creating a 8hock wave which will strike the carr~er membrane to inject the particles adherin~ to the opposite ~urface of the membrane into cell~ or ti~sue. once the pressure drops within the val~e chamber 160, the force of the magnet will retract the plunger into contact with the magnet and seal the valve opening by mean~ of the 0 ring 170.
Suitable bumper~ 176 are pro~ided on opposite sides of the ' ''' ''.''"'''~ , . .
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, 15 PAT~r ~iPPLICATION
plung~r plate to cu~;h~on the impact of ~ e plunger plate ~gainst the housing and the valve boay.
The entire di6clo~ure o~ the provisional applicatlon upon which pr~ority is claimed, i~ hereby incorpor~ted into the present appl~ation by reference.
. While the invent~on ha~ been particularly ~hown and described with reference to preferred embodi.ments thereof, it will be und~rstood by those in ~he art that the foregoing ~nd other chang~s in form and aetails may be ma~e therein without departing from the ~pirit and scope of the invention~
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