JOURNAL OF AEROSOL MEDICINE AND PULMONARY DRUG DELIVERYVolume 21, Number 2, 2008© Mary Ann Liebert, Inc.Pp. 000–000DOI: 10.1089/jamp.2007.0672

Anti-inflammatory Effect from IndomethacinNanoparticles Inhaled by Male Mice

ANDRE A. ONISCHUK,1 TATJANA G. TOLSTIKOVA,2 IRINA V. SOROKINA,2NATALJA A. ZHUKOVA,2 ANTOLY M. BAKLANOV,1 VLADIMIR V. KARASEV,1GALINA G. DULTSEVA,1 VLADIMIR V. BOLDYREV,3,4 and VASILII M. FOMIN5

ABSTRACT

The respiratory system provides entry for drug nanoparticles to cure systemic diseases. Themodern devices that are available on the market of therapeutic aerosol delivery systems havea number of disadvantages. There remains a need for an alternative means that is low cost,convenient, and capable of producing small-sized particles. On the other hand, one-third ofthe modern drugs are poorly water soluble. Many currently available injectable formulationsof such drugs can cause side effects that originate from detergents and other agents used fortheir solubilization. The aerosol lung administration may by a good way for delivery of thewater-insoluble drugs. We present here a new way for the generation of drug nanoparticlessuitable for many water insoluble substances based on the evaporation–condensation route.In this paper the indomethacin nanoaerosol formation was studied and its anti-inflammatoryeffect to the outbred male mice was examined. The evaporation–condensation aerosol gener-ator consisted of a horizontal cylindrical quartz tube with an outer heater. Argon flow wassupplied to the inlet and the aerosol was formed at the outlet. The particle mean diameterand number concentration were varied in the ranges 3 to 200 nm and 103 to 107 cm�3, re-spectively. The liquid chromatography and X-ray diffraction methods have shown thenanoparticles consist of the amorphous phase indomethacin. The aerosol lung administrationexperiments were carried out in the whole-body exposure chamber. Both the lung depositeddose and the particle deposition efficiency were determined as a function of the mean parti-cle diameter for mice being housed into the nose-only exposure chambers. The anti-inflam-matory action and side pulmonary effects caused by the inhalation of indomethacin nanopar-ticles were investigated. It was found that the aerosol administration was much more effectivethan the peroral treatment. The aerosol route required a therapeutic dose six orders of mag-nitude less than that for peroral administration.

Key words: indomethacin, nanoparticles, aerosol drug administration, particle lung deposi-tion, mice, anti-inflammatory effect

1

1Institute of Chemical Kinetics & Combustion, RAS, Novosibirsk, 630090, Russia.2Institute of Organic Chemistry, RAS, Novosibirsk, 630090, Russia.3Scientific and Education Centre “Molecular design and ecologically safe technologies,” Novosibirsk State Univer-

sity, 630090, Russia.4Institute of Solid State Chemistry & Mechanochemistry, RAS, Novosibirsk, 630090, Russia.5Institute of Theoretical and Applied Mechanics, RAS, Novosibirsk, 630090, Russia.

INTRODUCTION

THE ADMINISTRATION OF DRUGS directly into therespiratory tract has been used in a number

of therapeutic areas. The field for aerosolizeddrug application includes treatment of lung dis-eases, like asthma, chronic obstructive pul-monary disease, cystic fibrosis, and lung can-cer.(1) The aerosol delivery has expanded also intothe field of systemic drug delivery.(2) One of thegood examples of the expanding role of aerosoltherapy is the development of insulin as anaerosol to treat diabetes.(3,4) The optimal targetwithin the lungs for delivery of drugs to the sys-temic circulation is the alveolar region. For rapiddelivery, the alveolar drug administration has anumber of advantages including the large ab-sorptive surface area, easy permeability of thealveolar walls resulting in the fast passage fromthe alveolar airspace to the pulmonary capillarybed, direct connection between the pulmonarycirculation and the systemic circulation. Theaerosol delivery for some drugs (like, e.g.,zanamivir(1) or amantadine hydrochloride(5)) ismuch more efficient then the peroral administra-tion because of low oral bioavailability. The mod-ern devices that are available on the market oftherapeutic aerosol delivery systems can be sub-divided into three groups: nebulizers, dose-me-tering inhaler systems, and dry powder in-halers.(1,6) All these inhalers have evidentshortcomings.(1) One of the main problems for the

jet nebulizers is their limited portability due tothe need for compressed gas supply. Also, it isimportant that the nebulizer solutions should notbe stored in nebulizer reservoirs due to the pos-sible growth of bacteria. The disadvantages ofpressurized dose-metering inhaler systems in-clude high aerosol velocity (which results in sub-stantial oropharyngeal deposition), limited singledose, etc. Different facilities including extensiontubes and spacers were applied to overcomesome of these problems; however, new problemshave appeared like large spacer volume and par-ticle electric charge.(7) One of the problems for drypowder inhalers is that the dry powder formula-tion should be appropriately prepared. The pow-der properties are shelf life dependent. The cru-cial question is hygroscopicity. Thus, the aerosolproperties and the lung deposition efficiency canbe functions of the powder storage time.

The lung deposition efficiency for the abovesystems normally does not exceed 10%.(1) Allthese devices are able to generate the particles assmall as a few microns in diameter. However, thealveolar deposition efficiency is a strong functionof the particle size. The particles 10 to 20 nm insize deposit to the alveolar region about fourtimes more efficiently than those several micronsin diameter.(1,8–10) Therefore, a possible way toachieve higher deposition efficiency (and, proba-bly, to overcome some of the traditional inhalershortcomings) is to develop a new-type genera-tor for nanometer-size range. The possible alter-

ONISCHUK ET AL.2

FIG. 1. Scheme of the experimental setup for inhalation experiments.

native to nebulizers, metered-dose, and dry pow-der inhalers is evaporation–condensation route,11,12

which combines the possibility to generate a fineaerosol with the particle diameter 1 to 100 nm andthe number concentration as high as 108 cm�3.(13)

The problem is that the evaporating substancemust be thermally stable. In addition, differentformulations require different heating tempera-ture. Thus, the evaporation–condensation way ofaerosol delivering is waiting for the detailed in-vestigation.

Approximately one-third of the modern drugsare water insoluble or poorly water soluble. Manycurrently available injectable formulations ofsuch drugs can cause side effects that originatefrom detergents and other agents used for theirsolubilization. Also, water-solubility problemsdelay or completely block the development ofmany new drugs and other biologically usefulcompounds. Thus, the lung deposition route canbe a good alternative for the administration ofpoorly soluble substances. Indomethacin, whichhas low water solubility of 25 mg/L, is one of thecandidates considered for the lung delivery.(14)

Indomethacin is a well-known nonsteroid anti-in-

flammatory drug for use against a wide range ofdiseases such as rheumatoid arthritis, spondylo-sis, chondrosis. However, its side effects cancause serious disorders such as bleeding and per-foration of gastrointestinal tract, depression,drowse, mental disorder, increased blood pres-sure, congestive heart failure, etc. One may hopethat the aerosol lung administration of in-domethacin may be an alternative route whichwould diminish side effects and decrease thetherapeutic dose. However, new side effects likepulmonary emphysema are possible. Therefore,it is necessary to estimate the therapeutic benefitas well as possible risks from indomethacinaerosol administration.

In this paper we study the evaporation–con-densation formation of indomethacin nanoparti-cles and its anti-inflammatory effect, as well asside effects to the outbred male mice.

MATERIALS AND METHODS

The scheme of inhalation experiment is shownin Figure 1. The evaporation–condensation aerosol

ANTI-INFLAMMATORY EFFECT FROM INDOMETHACIN NANOPARTICLES IN MICE 3

FIG. 2. Nose-only exposure glass chambers.

generator consists of a horizontal cylindricalquartz tube (with the inner diameter of 1.50 cm)with an outer heater. Argon flow is supplied tothe inlet of the generator at the rate of 8 cm3/sec(at standard temperature and pressure). The ma-ternal substance (Indomethacin, ICN-190217) isput to the hot zone inside the tube. The saturatedvapor is formed inside the generator. The tem-perature drops down at the outlet of the tube re-sulting in vapor supersaturation and, as a conse-quence, in the homogeneous vapor nucleation.Then the aerosol is diluted up to the necessaryconcentration using an aerosol diluter (based onflow splitting, filtering one of the subflows andmixing the subflows again). The final aerosol ismixed with the air flow (at the flow rate of 100cm3/sec) and admitted into the plastic whole-body (WB) exposure chambers 300 cm3 volume.Two chambers were used in parallel; thus, theaerosol flow rate was about 50 cm3/sec in eachchamber. Each chamber contained two mice dur-ing the experiment. The outbred laboratory malemice of 25 to 30 g body weight were used in theaerosol inhalation experiments. The inhalationtime in all the experiments was 20 min. Theaerosol concentration and size distribution weremeasured with the aerosol spectrometer de-signed and built at the Institute of Chemical Ki-netics and Combustion, Novosibirsk, Russia.(15)

This aerosol spectrometer consists of an auto-matic diffusion battery, condensation chamber,and photoelectric counter. The spectrometer mea-sured the aerosol number concentration and par-ticle size distribution at the chamber inlet andoutlet during the exposition time. The aerosol de-pletion in the WB chambers did not exceed a fewpercent. Therefore, later, when evaluating thelung deposited dose, we will put the aerosol con-centration in the WB chambers as equal to the in-let concentration.

To determine the lung deposited dose specialexperiments were carried out. Nose-only expo-sure (NOE) glass chambers were used to mini-mize the skin or fur effect. The laboratory animalswere confined so that only nose was exposed tothe aerosol (Fig. 2). The aerosol flow was switch-ing between two parallel lines. Each line con-tained six chambers in tandem (Fig. 3). One linewas loaded with the animals; the other one hadempty chambers. The aerosol depletion due to themice breathing was determined by comparing theindomethacine particle concentration at the out-

lets of loaded and unloaded lines as measured bythe aerosol spectrometer.

The breathing frequency of the mice beingloaded to the NOE chambers was measured asshown in Figure 4. The air flux seeded with NaCltracing particles about 0.3 �m in diameter wassupplied through the chamber. The particles weregenerated by the collison-type nebulizer. Initially,this device generated the liquid NaCl/water so-lution particles that transform to the solid NaClparticles due to the immediate water evaporationwhen coming out of the nebulizer. The particlenumber concentration was as low as about 103

cm�3 to decrease the mouse airway irritation toa minimum. The flow rate through the chamberwas modulated by the mouse breathing. To mea-sure the flow rate, the seeding particles were il-

ONISCHUK ET AL.4

FIG. 3. Scheme of the experimental setup for the lungdeposited dose measurements.

luminated by the laser beam modulated with thefrequency of 1 kHz. A semiconductor amplitudemodulated laser KLM-M650-24 was used. The il-luminated particles were observed with a high-frequency video camera “Videoscan” at the an-gle of 90° (see insert in Fig. 4) to determine theflow velocity. Figure 5 shows a representativebreathing pattern.

A histologic analysis was performed to observethe indomethacin aerosol effect on the mice lungsmorphology. The mice were killed 6 h after ex-posure. Lungs were fixed in 4% paraformalde-hyde in the phosphate buffer (pH 7.2–7.4). Thefixed tissues were treated in a standard way us-ing histological equipment “MICROM” (CarlZeiss, Thornwood, NY) and then embedded to

ANTI-INFLAMMATORY EFFECT FROM INDOMETHACIN NANOPARTICLES IN MICE 5

FIG. 4. Scheme of the experimental setup to measure the mice breathing pattern.

paraffin. Sections 3–4 �m thick were stained withhematoxylin and eosin. Slides were examined un-der the light microscope Axioskop 40 (Carl Zeiss).

RESULTS AND DISCUSSION

Aerosol size, concentration, and composition

The mean particle size and number concentra-tion (as measured at the WB chamber inlet) areshown in Figure 6 as a function of generator tem-perature. The typical size spectrum is shown inFigure 7. The chromatographic analysis of theaerosol particles was performed to make sure thatthere was no thermal decomposition of in-domethacin during evaporation–condensation.For this purpose, the aerosol particles were sam-pled by passing the aerosol flux through the Pe-trianov high-efficiency aerosol filter.(16) Then thedeposit was dissolved in acetonitrile. High-per-formance liquid chromatograph Milikhrom-1equipped with a UV-spectrophotometric detectorwas used with a standard column packed withLiChrosorb C18 sorbent. The eluent was acetoni-trile–H2O–LiClO4–H3PO4. Elution rate was 50�L/min. The chromatographic analysis showedthat the chromatogram from nanoparticles wasidentical to that from the original indomethacinsample (Fig. 8). Thus, one may suppose that thenanoparticles are chemically identical to the orig-inal substance.

The crystal phase analysis of nanoparticles wascarried out using X-ray diffractometer systemBruker-AXS D8 Discover with GADDS area de-

tector. The powder X-ray diffraction patterns ofnanoparticles and �-indomethacin original pow-der are compared in Figure 9. The XRD patternof nanoparticulate material contains a broad halouncorrelated with the crystalline peaks, which is typical for the amorphous indomethacin.(17)

ONISCHUK ET AL.6

FIG. 5. Typical mouse breathing pattern as obtainedfrom the video observation of the breathing-modulatedair flow rate.

FIG. 6. Mean nanoparticle diameter and number con-centration (as measured at the WB chamber inlet) versusthe temperature of aerosol generator.

FIG. 7. Typical diameter distribution for indomethacinparticles.

Thus, the evaporation–condensation route resultsin the formation of amorphous nanoparticles.

Lung deposited dose

To determine the lung deposited dose we havemeasured the fraction � of particles that were con-sumed per chamber due to the mouse breathing:

� � 1 � � �1/N

(1)

where n and n0 are aerosol number concentra-tions at the outlets of the loaded and unloadedNOE lines, respectively, N is number of chambers

n�n0

in the tandem (see Fig. 3). The rate D [sec�1] ofparticle lung deposition per mouse can be writ-ten as:

D � F�n0, (2)

where F is flow rate though the NOE chamberstandem.

One can also use the relative deposition rate

D0 � . (3)

On the other hand:

D0 � fVT� (4)

where f, VT, and � are average mouse breathingfrequency, tidal volume, and particle lung depo-sition efficiency (the number of exhaled to thenumber of inhaled particles ratio), respectively.Figure 10 shows the relative deposition rate D0 asa function of the mean particle diameter. The lo-gistic regression analysis applied to the relativedeposition rate data showed that there was a sta-tistically significant correlation between the par-ticle diameter and the relative deposition rate(R2 � 0.96). The fitted curve is shown as solidline.

To determine the particle deposition efficiencyone should know both the mouse breathing fre-quency and the tidal volume. Using the tracingparticles technique (Figs. 4 and 5) we determinedthe mean respiration frequency for the mice usedin the inhalation experiments: f � 5.0 � 0.2 c�1.We used the value of tidal volume VT � 0.16 cm3

D�n0

ANTI-INFLAMMATORY EFFECT FROM INDOMETHACIN NANOPARTICLES IN MICE 7

FIG. 8. Comparison between the chromatograms of theoriginal indomethacin sample and nanoparticles formedby evaporation–condensation route.

FIG. 9. Comparison between the X-ray diffraction pat-terns from original �-indomethacin powder and nanopar-ticles formed by evaporation–condensation.

FIG. 10. Relative deposition rate per mouse versus meanparticle diameter. Bars indicate standard error. Line is lo-gistic regression analysis result.

as determined in plethysmographic measure-ments for CD-1 and HA/ICR mice with the bodyweight of 25–30 g.(18) Then the particle lung de-position efficiency � was evaluated from Equa-tion (4) using the experimentally measured D0.The particle deposition efficiency as a function of

the mean particle diameter is shown in Figure 11.The logistic regression analysis applied to the to-tal lung deposition efficiency data showed thatthere was a statistically significant correlation be-tween the particle diameter and � (R2 � 0.96). Thefitted curve is shown as solid line. One can seethat � tends to unity at small diameter values,which is in good agreement with numerical sim-ulations for the particle lung deposition.(9) Thus,the good agreement between the literature simu-lation results and our evaluated � testifies that weused the correct value for VT.

Anti-inflammatory effect of indomethacin nanoparticles

Each animal was used only once in the in-halation procedure and sacrificed at the end ofthe experiment. The mice were separated intothree groups (8–10 animals in each). The animalsof the first group (untreated) were not exposedto indomethacin (neither peroral nor by aerosolinhalation); the animals of the second group(peroral) were treated orally with the water–Tween suspension of indomethacin with 15 mg

ONISCHUK ET AL.8

FIG. 11. Mouse respiratory deposition efficiency versusmean particle diameter. Bars indicate standard error. Lineis logistic regression analysis result.

TABLE 1. EDEMA INDEX FOR TREATED AND UNTREATED ANIMALS

Group Animal Edema Mean edema Relativenumber number Treated Untreated index, % index, % edema index

1 1 193 160 20.6 20.3 � 1.9(untreated) 2 186 150 24.0

3 187 145 29.04 150 130 15.45 203 177 14.76 170 149 14.17 204 168 21.48 179 145 23.4

2 1 187 167 12.0 12.2 � 1.6(peroral) 2 183 173 11.6

3 173 160 8.14 178 156 14.15 174 162 7.06 170 154 10.47 204 176 15.98 174 163 6.79 179 144 24.3

10 152 170 11.83 1 200 177 13.0 7.3 � 1.2

(aerosol 2 171 157 8.9group) 3 159 155 2.3

4 160 147 8.45 178 170 4.76 157 151 4.07 179 165 8.58 158 171 8.2 0.36 � 0.06

Standard errors are shown in the last column.

Weight of paw, mg

the weight of the untreated hind paw was usedas an index of paw edema. Table 1 gives an ex-ample of the edema index for the groups 1 to 3.The particle number concentration and mean di-ameter were 7 � 105 cm�3 and 37 nm, respec-tively, in these experiments, which corre-sponded to the average lung deposited dose of1.4 � 10�5 mg per mouse (5.1 � 10�4 mg per kgbw). One can see a considerable anti-inflamma-tory effect from both aerosol and oral forms ofindomethacin—the mean edema index (MEI) forthe groups 2 and 3 is considerably less than thatfor the control group 1. The indomethacinaerosol form is more effective than the in-domethacin peroral treatment (MEI � 7.1% and12.2%, respectively), while the lung depositeddose is a few orders of magnitude less than theperoral dose. It is more convenient to use the rel-

ANTI-INFLAMMATORY EFFECT FROM INDOMETHACIN NANOPARTICLES IN MICE 9

per kg bodyweight (bw); the animals from thethird group (aerosol group) were subjected tothe aerosol inhalation. The mice from all thethree groups were put to the WB chambers for20 min. The mice from the first and the secondgroups were exposed to the pure air; the miceof the third group were exposed to the aerosol(the average lung deposited mass was deter-mined from the NOE chambers experimentaldata using the amorphous indomethacin densityof 1.3 g/cm3). One hour after the chamber ex-position, 0.05 mL of 0.1% histamine solution inwater was injected into the subplanar surface ofthe mouse hind paw. Six hours later the micewere killed by cervical dislocation. Then themouse’s paws were cut off at the ankle joint andweighed. The ratio of the difference in weightbetween the treated and untreated hind paws to

FIG. 12. Mean relative edema index (REI) versus the lung deposited dose (circles). Bars indicate standard error. Theparticle mean diameter is shown at every point. The levels of statistical significance of differences of the edema in-dexes between the aerosolized and untreated groups were calculated using Students t-test and are indicated as *1 �p � 0.5, **0.5 � p � 0.05, ***0.05 � p � 0.001, ****p � 0.001. The fitted dose–response curve is shown as solid line. Tri-angle is REI for peroral treatment; this point is a mean value throughout six experimental trials (each trial includedgroups of 8 to 10 animals).

ONISCHUK ET AL.10

FIG. 13. Representative sections from the lungs of un-treated animal (group 1) (a), and animal treated by theaerosol of d � 200 nm (group 3.1) (b).

FIG. 14. A cross-section of the lung from a mouse treated with 200-nm nanoparticles showing enlarged airspaces.

ative edema index (REI), that is, the ratio be-tween the mean edema indexes for theaerosolized group (or peroral group) and un-treated group. Figure 12 shows the mean REI for

the aerosolized animals versus the lung de-posited dose as well as REI for the orally treatedanimals. These data were obtained during six experimental trials. Each trial involved one un-

treated group, one oral group, and two aero-solized groups treated with particles of differentsize. Thus, there are 12 points for the inhalationtreatments and one point for the peroral treat-ment (averaged over six treatments). In total, thedata presented in Figure 12 involve about 210animals. The REI data were analyzed for thedose–response relationship. The fitted curve isshown as the solid line. The regression analysisapplied to the REI results showed that there wasa statistically significant dose response (R2 �0.91). The EC50 was 2.7 � 10�6 mg per kg bw.The triangle symbol gives the mean REI for per-oral animals for comparison. One can see thatthe aerosol administration is more effective(gives less REI) than the peroral treatment evenat the lung deposited dose six orders of magni-tude less than the peroral dose. The mean par-ticle diameter is indicated for each point in thegraph. It is hardly possible to find any depen-dence on the particle size. Thus, the points forthe nearby diameters (e.g., 21, 22, 24 nm and 32,

35, 37 nm) seem to be following the basic ten-dency within the experimental accuracy. On theother hand, the points differing essentially bysize (180 and 37 nm; 35 and 4–5 nm) also followthe same tendency.

Histology of the lungs

A histologic analysis was performed to ob-serve possible hemodynamic abnormalities andpulmonary edema after the aerosol treatment.The animals were exposed to two kinds ofaerosol of d � 200 nm, with the lung depositeddose of 2.3 � 10�5 mg per kg bw (group 3.1) andd � 9 nm, with the dose � 1.2 � 10�5 mg per kgbw (group 3.2). The aerosol number concentra-tions in the WB chambers were 7.1 � 102 and7.4 � 105 cm�3, respectively. Group 1 again in-cluded untreated mice being exposed to the pureair in the chambers. Each group consisted of 8to 10 animals. The lungs of animals from bothgroup 3.1 and group 3.2 as well as from group

ANTI-INFLAMMATORY EFFECT FROM INDOMETHACIN NANOPARTICLES IN MICE 11

FIG. 15. A cross-section of the lungs of mice treated with 9-nm nanoparticles.

1 have a normal structure without any destruc-tive and hemodynamic pathologic changes (Fig.13). However, a moderate venous and arterialhyperemia was observed for all the animals ingroup 3.1. Two animals of this group have re-vealed the focal emphysematous dilatation ofthe respiratory bronchioles without any visiblevascular bed reduction (Fig. 14). All the animalsfrom group 3.2 have demonstrated the vascularand capillary hyperemia (which was consider-ably stronger than in the case of group 3.1). Anhomogeneous venous deposition (presumablyfibrin) was observed. Besides, typical emphyse-matous signs, stronger than in group 3.1, wereobserved, that is, the dilatation of bronchioli andalveolar channels, alveolar wall thinning, andpartial capillary bed reduction (Fig. 15).

CONCLUSIONS

The anti-inflammatory action and side pul-monary effects caused by the inhalation of in-domethacin nanoparticles were investigated. Tothis end, an evaporation–condensation systemwas developed that was able to generate aerosolnanoparticles within the size range of 3 � d � 200nm. The chromatographic analysis showed thatthe aerosol particles were chemically identical tothe maternal substance (i.e., there was no thermaldecomposition during the substance evapora-tion). The X-ray diffraction analysis showed thatthe indomethacin nanoparticles were amor-phous.

The lung deposited dose versus nanoparticlediameter was measured using the nose-only ex-posure chambers. Using the mean mouse respi-ration frequency as determined in the breathingmodulated flow rate measurements and the lit-erature value for the tidal volume, the total lungdeposition efficiency was evaluated as a functionof the mean particle diameter.

The inhalation experiments show that theaerosol administration is more effective (resultsin less edema index) than the peroral treatmenteven at the lung deposited dose six orders of mag-nitude less than the peroral dose. However, thelung histology analysis for the mice treated withthe small particles (d � 9 nm) at dose as small as10�5 mg per kg bw has revealed emphysematoussigns like the dilatation of bronchioles and alve-olar channels, alveolar wall thinning, and partialcapillary bed reduction.

ACKNOWLEDGMENTS

Financial support for this work was providedby the Siberian Branch of Russian Academy ofSciences (Interdisciplinary Integration Project no.78), the Russian Foundation for Basic Research(RFBR) (project no 07-03-00643a).

AUTHOR DISCLOSURE STATEMENT

All authors declare that no competing financialinterests exist.

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Received on October 15, 2007 in final form, February 20, 2008

Reviewed by:Peter Valberg

Gunter Oberdorster

Address reprint requests to:Andrei Onischuk Dr. Sci.

Institute of Chemical Kinetics and CombustionSiberian Branch of Russian Academy of Sciences

Institutskaja Str., 3Novosibirsk, 630090

Russia

E-mail: onischuk@kinetics.nsc.ru

ANTI-INFLAMMATORY EFFECT FROM INDOMETHACIN NANOPARTICLES IN MICE 13

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