Metrics EX1010, Page 1
`
`Metrics EX1010, Page 1
`
`

`
`JOURNAL OF
`
`EDWARD G. FELDMANN,
`editor
`SAMUEL W. GoLDSTEIN,
`assistant editor
`YvETTE W. GoRDON,
`editorial assistant
`
`Editorial Advisory Board
`J. H. BURCKHALTER
`TROY C. DANIELS
`GEORGE P. HAGER
`W. W. HILTY
`THOMAS J. MACEK
`VARRO E. TYLER, JR.
`
`Committee on Publications
`HOWARD C. NEWTON, chairman
`WILLIAM S. APPLE
`GROVER C. BOWLES
`HUGO H. SCHAEFER
`LINWOOJ? F. TICE
`
`The Journal of Pharmaceutical Sciences is
`published Inonthly by the Amedcan Pharma(cid:173)
`ceutical Association, at 20th & N ot·thampton
`Sts., Easton, Pa. Application to mail at
`second-class postage rates is pending at
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`All expressions of opinion and statethe·nts of
`supposed fact appearing in articles or edi(cid:173)
`torials carried in 'rr-ns JoURNAL ate pablished
`on the authority of the writer ovet whose ·
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`of the American Pharmaceutical Association.
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`Sub(cid:173)
`scription rates are subject to change without
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`ceutical Association may elect to red~ive the
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`d~,;~~eir annual ~o27.00 A.Ph.A. membership
`Claints-Missing numbers will not be sup(cid:173)
`plied if claims are received more than GO days
`af~er the date of the issue, or if loss was due to
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`rhe Association cannot accept responsibility
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`Change of Address_:Members and sub(cid:173)
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`
`©Copyright 19Gl, American Pharmaceutical
`Assoc~ation, 2215 Constitution Ave., N.W.,
`Waslungton 7, D. C.
`
`The Editor comments
`
`THE "NEW LOOK"
`
`When you received this issue of Tms JoURNAL, we
`hope you noticed a number of significant changes in
`its appearance and rnake-up. These innovations,
`which were decided upon after much consideration,
`consultation, and debate, were adopted for several
`reasons. Certainly, it was hoped that the plastic
`surgery performed on the face of the publication
`would serve to improve further its appearance and
`esthetic qualities. An even more important aspect
`than the external plastic surgery, however, is the
`orthopedic surgery worked upon the body of the
`issue.
`In this regard the reader should particularly
`note the various new features which are being
`inaugurated. The scope of the publication has
`been expanded to permit the inclusion of critical
`review articles, editorials, articles of a technical
`nature, and reports of proposed drug assays and
`specifications.
`
`With this extension in publication policy, no
`purpose appeared to be served by continued issuance
`of Drug Standards as a separate periodical. Hence,
`the latter publication has been merged into the
`present one.
`
`Another change of special note is the retitling of
`THIS JouRNAL. The former name, Journal of the
`American Pharmaceutical Association, Scientific Edi(cid:173)
`tion, was criticized as being nondescriptivc with
`regard to content, too unwieldy, easily subject to
`confusion with the Pract,ical Pharmacy Edition,
`and difficult to cite correctly in literature references.
`The new title, Journal of Pharmaceutical Sciences,
`appears to overcome all of these objections. We are
`well aware that librarians and others responsible for
`the indexing and cataloging of periodicals will hot
`receive this change with enthusiasi11. We believe,
`however, that any inconveniences arising wW rapidly
`disappear, and that from a long-range view, the
`change may be looked upon as beneficial even to
`them.
`
`We are also aware that some readers will view with
`nostalgia the passing of the old title. We can only
`request that these individuals be tolerant, and that
`they, along with our other readers, accept the new
`features as an earnest attempt upon the part of the
`editors to improve the appearance of THIS JouRNAL,
`and to enhance its prestige, usefulness, and reader(cid:173)
`interest.
`
`Metrics EX1010, Page 2
`
`

`
`Vol. 50, No. 4, April1961
`
`ES 2%, and Stepanol ME 1 %) surfactants used
`in the concentrations mentioned in parenthesis
`were studied for the release of medicament using
`three in vitro methods, (a) radioactive isotope,
`(b) ba:cteriological, and
`(c) physicochemical
`methods.
`2. The, general pattern of the release of me(cid:173)
`dicament from all of the ointment bases remained
`the same when tested by these methods.
`3., The ointment prepared with two per cent
`anionic surfactant, Sipon ES, was found to be the
`most satisfactory hydrophilic ointment base.
`The increase in concentration of Sipon ES re(cid:173)
`tarded the release of medicament from ointment
`bases in all three in vitro methods.
`4. A modified physicochemical method is
`suggested to increase the sensitivity and the speed
`of the color zones produced per unit of time.
`5. A comparative discussion of three in vitro
`methods has been presented and it was concluded
`
`305
`
`that the radioactive isotope method was superior
`in both sensitivity and accuracy as well as the
`quantitative results which can be obtained per
`unit of time.
`
`i!
`I
`
`REFERENCES
`(1) Lockie, L. D., and Sprowls, J. B., THis JoURNAL, 38,
`222(1949).
`(2) Stark, J. F., Christian, J. E., and DeKay, H. G., ibid.,
`47, 223(1958).
`.
`(3) Barker, E. Y., Christian, J, E., and DeKay, H. G.,
`ibid., 45, 501(1956).
`.
`(4) Wand, R. A., and Ramsay, A., Can. Med. Assbc. J.,
`48, 121(1943).
`(5) Ruehle, C. L. A., and Brewer, C. M., U.S. Food and
`Drug Admin. Circular, No. 198.
`(6) Izgu, E. and Lee, C. 0., J. Am. Pharm. Assoc., Pract.
`Pharm. Ed., 15, 395(1954).
`-
`(7) Urkami, C., and Christian, J. E., Tms JouRNAL,
`42, 179(1953).
`(8) Gemel, D. I-I. 0 .. and Morrison, ]. C., J. Pharm. and
`Pharmacal., 9, 641(1957).
`(9) Patel, K. C., Banker, G. S., and DeKay, H. G., THIS
`}OURNAL, 50, 294(1951),
`(10) "Visking Dialysis Tttbing-Technical Infonnation,"
`Viskiug Co., 6733 West 65th St., Chicago 38, Ill.
`(11) Livingood, J, J., and Seaborg, G. T., Physiol. Revs.,
`54, 775(1938).
`(12) Bell, R. E., and Gram, R. L., ibid., 86, 212(1952).
`(13) Fox, C. L., Winfield, J. M., Slobody, L. B., Swindler,
`C. M., and Lattimer, J, K., J. Am. Med, Assoc., 148, 827
`(1952),
`
`Solubilization of Anti~inflammatory Steroids by
`Aqueous Solutions of Triton WR-1339
`
`By D. E. GUTTMANt, W. E. HAMLIN,]. W. SHELL, and]. G. WAGNER
`
`Cleat· solutions 'of anti-inflammatory steroids, which have concentrations of steroid
`considerably greater than the water solubilities of the stet·oids, are being sold
`commercially for ophthalmic use. The present study was undertaken to obtain
`quantitative data on the solubilizing power of Triton WR-1339 for th1'ee anti-in(cid:173)
`flammatm·y steroids. The appat·ent solubility of each of the steroids, prednisolone,
`methylpt·ednisolone, and fluorometholone, in an aqueous solution of Triton WR-
`13 3 9 was found to be lineady dependent on the per cent Triton present. Both the
`slopes of the linear solubility plots and the watet· solubilities of the steroids at·e, in
`the ordet·, p1'ednisolone > methylprednisolone > fluorometholone. The marked
`diffet·ence in the solubility of fluorometholone in aqueous solutions of Triton WR-
`13 39 from the othet· two steroids having a 21-hydt'oxyl group indicates that an en(cid:173)
`tirely diffet•ent pha1'maceutical problem is involved with the steroid having the type
`of side chain present in fluo1'ometholone.
`
`vARIOUS AUTHORS (1-14) have reported the
`use of surface-active materials, e. g., proteins,
`bile salts, and surfactants, to solubilize steroid
`hormones. For ophthalmic use it is desirable to
`prepare clear solutions of anti-inflammatory
`steroids which have concentrations of steroid
`considerably greater than their water solubility.
`The surface-active materials used in such prep(cid:173)
`arations must have sufficient solubilizing power to
`attain the necessary steroid concentration and
`must be nonirritating and noninjmious .to the eye.
`Johnson (13, 14) studied a large number ·of
`
`Received June 3, 1950, ftotn the Research Laboratories,
`The Upjohn Co., Kalamazoo, Mich.
`Accepted for publication August 4, 1960.
`'I" Present address: College of Pharmacy, The Ohio State
`University,. Columbus.
`
`surfactants and found that both Triton WR-1339
`and Tween 80 were satisfactory for preparing
`suitable aqueous solutions of the adrenalcortical
`honnones. 1
`The present study was undertaken to obtain
`quantitative data on the solubilizing power of
`Triton WR-1339 for
`three anti-inflammatory
`steroids: prednisolone, methylprednisolone, ancl
`flttotometholone.
`
`EXPERIMENTAL
`
`Materials.-The prednisolone was recrystallized
`once from alcohol-water, then dried for twelve hours
`
`t Two of the comtnercial products are Eye Drops Optef,
`0. 2% and Eye Dl"Ops Neo-Deltef, 0. 2%, sold by The Upjohn
`Co.
`
`Metrics EX1010, Page 3
`
`

`
`306
`
`at 70°. The methylprednisolone and fluorometh(cid:173)
`olone were micronized. The Triton WR-1339 was
`obtained from Winthrop-Stearns.
`The structure of Triton WR-1339 ·according to
`Rohm and Haas Co. is as follows:
`
`p
`
`where n :::: 10 and p :::: 4. The calculated mole(cid:173)
`equivalent weight (n = 10, j; = 1) is 702.9, and the
`average molecular weight ( n = 10, p = 4) is 2,812.
`Equilibration.-Method A.-Excess steroid and
`the Triton-water solution were heated in a vial on the
`steam-bath for ten minutes before placing in a con(cid:173)
`stant temperature bath at 25.0° where the vials were
`The vials were al(cid:173)
`slowly rotated for two weeks.
`lowed to stand in the bath for one week.
`Some of
`the solubility studies with prednisolone were. done
`this way.
`Method B.-Excess steroid mid the Triton-water
`solution were slowly rotated in 10-cc. vials in a
`constant temperature bath at 25° for one week.
`Some of the solubility studies with prednisolone
`were done this way.
`Method C.-Excess steroid and the Tdton-water
`solution were vigorously agitated at 37° for two days
`then were vigorously agitated at room temperature
`(approximately 25°) for two clays. The samples
`were then allowed to stand for tht·ee clays at room
`temperature. This method was used for
`the
`solubility studies with methylprednisolone and
`fluorometholone.
`Assay Procedure.-Method I.-All Triton-water
`solutions containing prednisolone were assayed for
`steroid by withdrawing 5 mi. of supernatant from the
`vial, extracting the steroid with chloroform, evap(cid:173)
`orating 2 to 10 ml. of chloroform extract to dryness,
`taking up the steroid residue in ethanol, a.ncl assay(cid:173)
`ing the alcoholic solution by the triphenyltetra.zolium
`color procedure (15).
`Method 2.-All Triton-water solutions containing
`methylprednisolone or fluorometholone were assayed
`for steroid by determining the ultraviolet absorption
`spectmm of the sample solution after centrifugation
`using a. blank prepared with the same concentration
`of Triton as the sample and carried through the
`same equilibrium procedure a.s the sample. The
`aqueous Triton-flttorometholone solutions were
`diluted 1:20 and
`the aqueous Triton-methyl(cid:173)
`prednisolone solutions were diluted 1: 100 with 95%
`alcohol. The absorption maximum was used to
`calculate the concentration of steroid. An ab(cid:173)
`sorptivity ( 1%,1 em.) of 400 was used for both
`methylprednisolone and
`fluorometholone.
`Cal(cid:173)
`ibration data. indicated this absorptivity was valid
`since the presence of Triton at the dilutions used
`did not significantly change the value from that
`observed with 95% alcohol alone.
`Method 3.-For cletenuina.tion of the shift in the
`ultraviolet absorption maximum of the steroids in
`
`Journal of Pharmaceutical Sciences
`
`aqueous-alcoholic solutions of Triton WR-1339, an
`aliquot of the steroid in aqueous Triton solution
`was diluted to. 100 ml. with 95% alcohol. The
`ultraviolet absorption spectrum was obtained with
`a Cary recording spectrophotometer using a. blank
`prepared in the same way but without steroid.
`Reasonably low slit widths at or near the absorption
`maximum with the Cary instrument indicated that
`distortion had not occurred despite the fact that
`the Triton WR-1339 also had appreciable absorption
`in the 230 to 250 m,u region.
`
`RESULTS
`
`The observed solubilities of the steroids in water
`and aqueous solutions of Triton WR-1339 are
`shown in Table I.
`The apparent solubility of a steroid in an aqueous
`solution containing Triton WR-1339 was found to
`be linearly dependent on the per cent of Triton
`present. This relationship can be expressed by the
`equation
`
`S = So + a (Triton)
`(Eq. 1)
`where S = the apparent solubility of the steroid in
`aqueous Triton solution, So = the solubility in
`water, a = a constant representing the slope of the
`solubility curve, and (Triton) = the per cent (w /v)
`of Triton present.
`The data of Table I are plotted in Fig. 1. The
`constants of the "least-squares" regression lines are
`shown in Table II.
`
`TABLE I.-OBSERVED SoLUBILITIES OF THE STER(cid:173)
`oms· IN WATER AND AQuEous SoLUTIONS OF TinToN
`WR-1339
`
`T'riton
`WR-1339
`% w/v
`0
`
`2
`4
`5
`
`6
`
`7
`8
`
`9
`10
`
`12.5
`
`15.0
`
`~observed Solubility of Steroid, mg./mi.~
`
`Pred-
`nisolone
`0.223a,
`0.239b
`0.693a
`1, 196a,
`1. 458b
`
`1. 706a,
`1 '716b
`1' 881b
`2.219a,
`2. 217b
`2.481b
`2. 719a,
`2. 719b
`
`Methylpred-
`nisolonea
`0.0~5
`
`Flu oro-
`metholonec
`0.003,
`0.010
`
`0.065,
`0.080
`
`1.25
`
`1.52
`
`1. 80
`
`0. 103,
`0.090
`0.118,
`0.143
`
`a Equilibration procedure was method 'A; assay proCedure
`was method 1.
`b Equilibration procedure was methbd B; assay procedure
`was method 1.
`·
`o Equilibration procedure was method C; assay procedu1"e
`was methpd 2.
`
`TABLE H.-INTERCEPTS (So) AND SLOPES (a) OF
`iLINEAR PLOTS SHOWN IN FIG. 1
`
`Steroid
`Prednisolone
`Methylprednisolone
`Fluorometholone
`
`So, mg./mi.
`0.215
`0.097
`0.013
`
`a
`0.249
`0.114
`0.00927
`
`Metrics EX1010, Page 4
`
`

`
`Vol. 50, No, ,4, April1961
`
`0
`
`.
`I
`/o Prednisolone
`
`10
`
`2.0
`
`Melhylprednisolone
`
`l 0 I 10
`/0
`0 t~========l====Fiu=o=ro=m=el=ho=lol~'====-~~~·==-L_j
`5
`10
`15
`CONCENTRATION OF TRITON WR-1339 (% w/v).
`Fig. 1. The solubilities of some anti-inflammatory
`steroids in aqueous solutions of Triton WR-1339.
`
`TABLE III.==MAxrMUM SoLUBILIZING PowER OF
`TRITON WR-1339 FOR ANTI-INFLAMMATORY STER(cid:173)
`OIDS
`
`Moles of Moles-equiv.
`of Triton
`ll Steroid, mg/ ml. Steroid per
`Mole-equiv. WR-1339 per
`of Triton
`Mole of
`ll %w/v Triton
`Steroid
`WR-1339 WR-1339
`0.249
`0.0486
`20.6
`
`0.114
`
`0.0214
`
`46.7
`
`0.00927
`
`0. 00173
`
`578.0
`
`Steroid
`Prednisolone
`Methylpred-
`nisolone
`Fluorometh-
`alone
`
`TABLE IV.-SHIFT IN THE ULTRAVIOLET ABSORP(cid:173)
`TION MAXIMA OF THE STEROIDS IN AQUEOUS-AL(cid:173)
`COHOLIC SOLFTIONS OF TRITON WR-1339
`
`Triton
`WR-1339
`% w/v
`0
`5.0
`10.0
`12.5
`15.0
`
`A Max. of
`Fluoro-
`metholone, 1n,u
`243, 243.0
`243,243.5
`247, 247.0
`250, 251.0
`254, 255.0
`
`A Max. of
`Methyl(cid:173)
`prednisolone,
`1lll'
`
`241.3
`243.3
`243.7
`
`II
`il
`!I
`
`307
`
`observed in the case of solubilized polycyclic ar(cid:173)
`omatic hydrocarbons (16), for various steroids
`solubilized in aqueous sodium Iaury! sulfate ('!1),
`and for chloroxylenol solubilized
`in water by
`polyethylene glycol 1000 monoacetyl ether (17).
`This behavior is typical of instances where as(cid:173)
`sociation is possible with the solvenl by hydrogen
`bonding (3).
`It seems likely, therefore, that the
`steroids are associated with the polyoxyethylene
`chain of Triton WR-1339.
`When the slopes, a, of the linear solubility plots of
`Fig. 1 and Table II are plotted against the intercepts,
`So, an apparent straight line is obtained. This in(cid:173)
`dicates an apparent relationship ·between the water
`solubility of a steroid and its ability to be solubilized
`by Triton WR-1339. Although this relationship
`appears to be valid for the three steroids inves(cid:173)
`tigated, additional compounds must be studied to
`check the validity of the correlation for steroids as a
`general class.
`It is interesting to note that tte
`melting points of the steroids studied fall in the
`order, prednisolone 232-236 o, methyprednisolone
`240°, and fluorometholone 292-303°. This suggests
`that qualitatively similar energy interchanges occur
`in all three equilibritpn situations.
`
`SUMMARY AND CONCLUSIONS
`
`1. The solubilization of prednisolone, methyl(cid:173)
`prednisolone, and fluorometholone by aqueous
`solutions of Triton WR-1339 has been studied
`quantitatively.
`2. The apparent solubility of each steroid in
`an aqueous solution containing Triton WR-1339
`was found to be linearly dependent on the per
`cent of Triton present.
`3. The greater the water solubility of the
`steroid, the greater the solubilizing power of
`Triton WR-1339. Both the slopes of the linear
`solubility plots and the water solubilities of the
`steroids are in the order prednisolone > methyl(cid:173)
`prednisolone> fluorometholone.
`
`REFERENCES
`
`From the linear solubility curves we have calcu(cid:173)
`lated the saturation capacities of
`the nonionic
`surfactant, Triton WR-1339, for
`the respective
`steroids. These values are collected in Table III.
`In aqueous-alcoholic Triton solutions the steroids
`investigated showed ultraviolet absorption curves
`that were similar to those recorded in water-alcohol.
`However, as the concentration of Triton increased
`there was a shift in the absorption maximum toward
`longer wavelengths. Table IV
`indicates thes.
`~hifts in absorption maxima to longer wavelength~
`for
`fluorometholone and methylprednisolone
`in
`aqueous-alcoholic solutions of Triton.
`
`DISCUSSION
`
`The shifts in the absorption maxima of the
`steroids toward longer wavelength~ as the con(cid:173)
`centration of Triton increases is similar to that
`reported by other authors. Similar shifts were
`
`(1) Cautarow, A., J;'aschlds, K. E., RakofT, A. E., -and
`•
`Hausen, L. P., Endocrinology, 35, 129(1944).
`(2) Ekwf>ll, P., and Sjoblom, L., Acta C::hem. Scand., 3,
`1179(1949).
`(3) Ekwall, P., and Sjoblom, L., Acta Endoc>·inol., 4,
`179(1950).
`(4) · Ekwall, P., Lundsten, T., and Sjoblom, L., Acta
`Chem. Scand., 5, 1383(1951).
`(5) Van Meter, C. T. (to Reed & Carnrick), U. S. pat.
`2,600,344(1952).
`(6) Rothchild, J., Endocrinology, 50, 583(1952).
`(7) Ekwall, P., Sjoblom, L., and Olsen, J,, Acta Chem.
`Scand., 7, 347(1953).
`· .
`(8) Nakagawa, T, J. Pha1'1n. Soc. Japan, 73, 469(1953).
`(9) Eik-Nes, K., Schelltnau, J, A., Lumry, R, and
`Samuels, L. T., J. Bioi. Cltem., 206 411(1954).
`(10) Fischl, S., British pat. 758,550(1956).
`(11) Wes_tphal, U., A>·.ch. Biochem. Biophys,, 66, 71(1,957).
`(12) Zanow, M. X., Neher, G. M., Lazo-Wasem, E. A.,
`and Salhanick, H. A., J. Clin. Endocrinol. and Metabolism,
`17, 658(1957).
`(13)
`Johnson, R. H. (to The Upjohn Co.), U. S. pat.
`2,880,130(1959).
`(14)
`Johnson, R. H. (to The Upjohu Co.), U. S. pat.
`2,880, 138(1959).
`(15) Wagner, J, G., Dale, J, K., Schlagel, C. A., Meister,
`P. D., and Booth, R. E., THIS JoURNAL, 57, 580(1958),
`(16) Ekwall, P., Setola, K., and ;3joblom, L., Acta Chem.
`Scand., 5, 175(1951).
`(17) Mnlley~B. A., and Metcalf, A. D., J. Pharm. and
`Pharmacal., 8, 7'14(1956),
`
`Metrics EX1010, Page 5