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Jyorthana Rajappa Muralidhar, Kabilan Sakthivel, Madanagurusamy Sridharan, [Masanori Kikuchi](https://orcid.org/0000-0002-9451-8147)

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[Influence of Electrical Polarization on Thrombogenicity of Titania Nanotubes](https://mdr.nims.go.jp/datasets/c0718481-ef76-488a-a4dd-55c5f0dbe6f5)

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Influence of electrical polarization on thrombogenicity of titania nanotubesReceived: 21 January 2024 Revised: 25 February 2024 Accepted: 4 March 2024DOI: 10.1002/ces2.10214RESEARCH ARTICLEInfluence of electrical polarization on thrombogenicity oftitania nanotubesJyorthana Rajappa Muralidhar1,2 Kabilan Sakthivel1,2Madanagurusamy Sridharan2 Masanori Kikuchi11Bioceramics Group, National Institute forMaterials Science, Tsukuba, Japan2Centre for Nanotechnology & AdvancedBiomaterials and SEEE, SASTRAUniversity, Thanjavur, IndiaCorrespondenceMasanori Kikuchi, Bioceramics Group,National Institute for Materials Science,1-1, Namiki, Tsukuba, Ibaraki, 305-0044,Japan.Email: KIKUCHI.Masanori@nims.go.jpAbstractThe development of hemocompatible biomaterials with antithrombogenic sur-face coatings remains a challenge in cardiovascular applications. There is interestin negatively charged surfaces that inhibit thrombus formation through elec-trostatic repulsion between the biomaterial surface and negatively chargedplatelets. Hence, the present study investigated the influence of electrical polar-ization on the thrombogenicity of titania nanotubes (TNT), which are promisingcandidates for inhibiting thrombogenicity via surface modification. TNTs wereformed on commercially pure titanium plate by the electrochemical anodiza-tion technique using platinum as a counter electrode at 60 V for 24 h with twokinds of electrolytes (hydrofluoric acid diluted with dimethyl sulfoxide [D-TNT]or ethylene glycol [E-TNT]) followed by an annealing at 540◦C for 3 h in air.Both TNTs were mixture of anatase and rutile, and the D-TNT had a diameter of108.76 ± 2.55 nm and the E-TNT, 53.833 ± 2.42 nm. The TNTs were electricallypolarized at 100 V of DC field and 400◦C for 1 h. Water contact angle measure-ments showed that the non-polarized (0-) TNT surface was hydrophilic whereasthe positively (P-) or negatively (N-) polarized TNT surfaces showed high-hydrophilicity. Antithrombogenicity was evaluated using the thrombus coveragearea ratio (TCAR) after soaking the TNTs in bovine whole blood. The TCARs for0-polarized E- andD-TNTswere 5.30± 4.34% and 36.3± 5.8% and for P-polarizedE-TNT and D-TNT were 1.50 ± 0.77% and 2.76 ± 1.07%, whereas no thrombusformation (0 ± 0%) for N-polarized E-TNT and very few thrombus formation(0.12± 0.22%) for N-polarized D-TNT. The electrostatic repulsion between the N-polarized E-TNTs and platelets completely inhibits thrombus formation, whichcannot be achieved by the nanomorphology and high-hydrophilicity of otherTNTs. Hence, N-TNTs formed by electrical polarization are potential candi-dates for cardiovascular devices, such as artificial heart valves with long-termhemocompatibility.This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided theoriginal work is properly cited.© 2024 The Authors. International Journal of Ceramic Engineering & Science published by Wiley Periodicals LLC. on behalf of the American Ceramic Society.Int J Ceramic Eng Sci. 2024;e10214. wileyonlinelibrary.com/journal/ces 1 of 9https://doi.org/10.1002/ces2.10214https://orcid.org/0000-0002-9451-8147mailto:KIKUCHI.Masanori@nims.go.jphttp://creativecommons.org/licenses/by/4.0/https://wileyonlinelibrary.com/journal/ceshttps://doi.org/10.1002/ces2.10214http://crossmark.crossref.org/dialog/?doi=10.1002%2Fces2.10214&domain=pdf&date_stamp=2024-03-182 of 9 MURALIDHAR et al.KEYWORDSbiocompatibility, nanotubes, polarization, surface modification, titanium dioxide1 INTRODUCTIONAn initially adsorbed protein layer on the blood-contactbiomaterial surfacemainly triggers adverse reactions, suchas the activation of coagulation via the intrinsic pathway,activation of leukocytes, which results in inflammation,and adhesion and activation of platelets.1 Consequently,the number of blood cells can decrease, and a throm-bus can be formed.2 To overcome this drawback, blood-thinning medications are often prescribed to patients whouse blood-contact devices. Antiplatelet drugs or antico-agulants were administered to reduce thrombogenicity.Such therapies can increase the risk of heart failureand internal bleeding.3 Pre-clotting the implant surfaceby exposing it to the patient’s blood prior to implanta-tion is another way to inhibit thrombogenicity. However,this method is only applicable to porous implants, suchas vascular grafts, and is not suitable for valves andcatheters.4The surface of blood-contact biomaterials has beenmodified by synthetic and natural materials; for instance,heparin is used as a coating for stents and catheters5–7and pyrolytic carbon is used as a coating for artificialheart bulbs. However, these strategies are insuffi-cient for achieving long-term hemocompatibility.8Therefore, the development of material surfaces withlong-term hemocompatibility remains a significantchallenge.Titanium (Ti) and its alloys have been of great interestbecause of their excellent biocompatibility owing tothe formation of a stable oxide layer (passive film) ontheir surface,9,10 however, the passive films on Ti and itsalloys are not sufficient for intravascular use. Tubularnanotopographical cues of Ti metal, titania nanotubes(TNT), were reported to provide a better interface betweenthe Ti and the surrounding tissues. Previous studieshave shown enhanced hemocompatibility of these TNTarrays.11–13 Increase in the production of endothelial cellextracellular matrices on TNT was also reported.14–16TNTs have been widely used for cardiovascular stentbecause of its prevention of platelet and smooth musclecell adhesion and activation on to stent surfaces andsupport the growth of human coronary artery endothelialcells.17 However, a thrombogenicity evaluation of TNTrevealed presence of some risks of forming thrombosison the surface of the TNT.13 Some of the factors thatinfluence the material’s biocompatibility are their sur-face roughness,18 surface chemistry,19 surface energy(hydrophobicity/hydrophilicity),20 crystallinity,21 andconcentration.22 The current approaches mainly focus onsurface modifications with biological anticoagulants suchas heparin, or anti-fouling molecules like tanfloc/heparinpolyelectrolyte multilayers on TNT array surfaces.23Superhemophobic TNT surfaces were developed by mod-ifying the TNT with alkyl and fluorinated silanes using achemical vapor deposition technique.24 SuperhemophobicTNT was also investigated for blood-contacting devicesas it can decrease surface protein adsorption/factor XIIactivation and delay thrombogenesis.25 Thus, Ti coatedwith TNTs is a promising candidate to inhibit throm-bogenicity but it still requires further modification toenhance antithrombogenicity.Saito et al. reported that the negatively charged surfaceof a biomaterial has the potential to inhibit thrombogene-sis by the electrostatic prevention of platelet adsorption onthe material surface.26 This suggests that the permanentlynegatively charged TNT surface enhances the inhibitionof thrombus formation by electrostatic repulsion betweenthe Ti surface and negatively charged platelets, in addi-tion to its high-hydrophilicity and nanostructure. To thebest of our knowledge, no previous study has reportedthe development of negatively charged TNTs using elec-trical polarization for hemocompatibility. In this study,negatively charged TNTs were developed by electricalpolarization, and their influence on antithrombogenicitywas investigated by evaluating thrombus formation on thesurface of TNTs using anti-coagulated bovine whole bloodwith the activation of blood coagulation by the addition ofcalcium chloride (CaCl2).2 MATERIALS ANDMETHODS2.1 MaterialsTi sheets (>99.5%, 0.5 mm in thickness) and platinum(Pt) foil (99.99% purity) were purchased from NilacoCo. Formaldehyde, hydrofluoric acid (HF, 48%), ethy-lene glycol (EG, C2H6O2, 99%), and dimethyl sulfoxide(DMSO, [CH3]2SO, 99.7%) were purchased from WakoPure Chemicals, Inc. Calcium (Ca) and magnesium(Mg)-free phosphate-buffered saline was purchased from Dul-becco’s PBS (DS Pharma Biomedical). Six-well tissue cul-ture plates were purchased from Falcon. Anti-coagulated 25783270, 0, Downloaded from https://ceramics.onlinelibrary.wiley.com/doi/10.1002/ces2.10214 by Cochrane Japan, Wiley Online Library on [18/03/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons LicenseMURALIDHAR et al. 3 of 9F IGURE 1 Flow of antithrombogenicity study.bovinewhole blood (cat. no. 12070610, lot. no. 7097062)waspurchased from COSMO Bio Co. Ltd.2.2 Synthesis of TNTTNTs were fabricated using an electrochemical anodiza-tion technique27–30 with a Ti sheet as the anode and aPt sheet as the cathode. Commercially pure Ti sheets(2× 1 cm) and Pt foil (2.5× 2.5 cm)were cleaned in acetone,isopropyl alcohol, and methanol using ultrasonication for15 min each. They were then sonicated in distilled ion-exchanged (DI) water for 5 min, rinsed with DI water, anddried. The Ti sheet was anodized using a two-electrodesetup at room temperature and 60 V for 24 h with 100 mLof the electrolyte. Two types of TNT were prepared usingdifferent electrolytes. One was D-TNT from HF/DMSO,which was constituted of 2% of volume of 48% HF inDMSO, and another was E-TNT from HF/EG, which wasconstituted of 0.5% of mass of HF in EG. The voltageand anodization time were fixed in both the cases. Theanode and cathode were separated by 2 cm in the elec-trolyte. After anodization, the TNT substrate was rinsedthrice with DI water and air-dried at room temperature.The dried TNT filmwas annealed in an oxygen atmosphereat 540◦C for 3 h at a heating rate of 1◦C/min to obtain crys-talline substrates. The TNTs prepared with HF/DMSO andHF/EG are denoted as D-TNTs and E-TNTs, respectively.2.3 Electrical polarization of TNTAnnealed TNT was polarized by placing the film betweena pair of Pt-foil at 100 V of DC field and 400◦C for 1 h.31The polarization conditions were positively charged(P-polarized) from the cathode, negatively charged(N-polarized) from the anode, and as-prepared (non-polarized/0-polarized) TNT. To verify the reproducibilityof the results, five samples were prepared for eachcondition.2.4 Characterization of TNTThe surface morphology of the TNT was observed usingfield-emission scanning electron microscopy (FE-SEM, S-4800, Hitachi Co.). The crystalline phases of the TNTswere identified by the powder X-ray diffractometry (XRD, 25783270, 0, Downloaded from https://ceramics.onlinelibrary.wiley.com/doi/10.1002/ces2.10214 by Cochrane Japan, Wiley Online Library on [18/03/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License4 of 9 MURALIDHAR et al.F IGURE 2 Field emission- scanning electron microscopy (SEM) images of D-TNTs. (A) Isle-like conjugated D-TNT, (B) top view (tubestructure) of D-TNT, (C) thickness of D-TNT layer, and (D) side view of D-TNT (magnified [C] image). D-TNT, dimethyl sulfoxide; TNT,titania nanotubes.F IGURE 3 Field emission-scanning electron microscopy (SEM) images of E-TNTs. (A) Wall-like conjugated E-TNT, (B) top view (tubestructure) of E-TNT shows that walls were thinner than D-TNT shown in Figure 2B, (C) thickness of E-TNT layer which was slightly thinnerthan that of D-TNT shown in Figure 2C, and (D) side view of D-TNT (magnified [C] image) which was denser than that of D-TNT shown inFigure 2D. E-TNT, ethylene glycol; D-TNT, dimethyl sulfoxide; TNT, titania nanotubes.RINT-Ultima III, Rigaku Co.) from 10◦ to 80◦ of 2θ at ascanning rate of 2◦/min using carbon monochromatizedCuKα. The surface roughness of TNTwas evaluated by theatomic force microscopy (AFM, E-Sweep with NanonaviII, SII). The TNTs were qualitatively analyzed by energy-dispersive X-ray spectroscopy (EDX, SU 8230, Bruker Inc.).To ensure that the TNT had a high electrical resistance andlow electrical conductivity for electrical polarization, bothwere measured using a multimeter. The contact angle ofthe DI water on the TNT layer wasmeasured using the ses- 25783270, 0, Downloaded from https://ceramics.onlinelibrary.wiley.com/doi/10.1002/ces2.10214 by Cochrane Japan, Wiley Online Library on [18/03/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons LicenseMURALIDHAR et al. 5 of 9sile water drop method and a goniometer (Contact AngleMeterDM-CE1, FAMAS,Kyowa) to evaluate itswettability.2.5 Antithrombogenicity evaluationThe thrombogenicity of the TNT was tested according toa previous report,32 using glass as a positive control andbare Ti as a control. The specimens were incubated in Ca-and Mg-free phosphate buffered saline at 37◦C for 1 h. Thecells were transferred to a six-well tissue culture plate witha pair of specimens in eachwell (Figure 1). A total of 1.5mLof bovine blood was added to each well and was incubatedat 37◦C for 1 h. After the incubation, blood coagulationwas activated by adding 150 µL of 0.1 M CaCl2 aqueoussolution in each well followed by mixing. Subsequentlyafter 8–10 min of incubation, 5 mL of DI water was addedto arrest coagulation. The specimens with thrombi werewashed with PBS thrice, fixed with 37% formaldehyde for1 h at room temperature, dehydrated serially using 60%,70%, 80%, 90%, and 100% ethanol for each 15 min, andfinally dried under vacuum. Digital images of samples andcontrols were captured using a digital camera (K-01, PEN-TAX, Japan) at 16.28 × 106 pixels. The area of the thrombusformed on each sample in 1 × 1 cm from the edge of theTi plate, as shown in Figure 1, is measured using ImageJ(Windows7, 64-bit Java 1.8.0_112, NIH).2.6 Statistical analysisStatistical analysis was performed using one-way analysisof variance (ANOVA), followed by post hoc Tukey’s analy-sis using Kaleida Graph (Ver. 4.5 (Macintosh) to determinestatistical significance among the samples at p < 0.5 as thelevel of significance.3 RESULTS AND DISCUSSION3.1 Surface characteristics of TNTAll the results shown in the following are for the annealedTNT, except for Figures 2 and 3 that show FE-SEM imagesof D- and E-TNTs, respectively. The D-TNT showed an isle-like structure formed by the conjugation of the D-TNT;in contrast, the E-TNT showed a wall-like structure. Thediameters, wall thicknesses, and lengths of both TNT aresummarized in Table 1. All D-TNT values were approx-imately two to three times larger than those of E-TNT.Furthermore, thinner fibrous nanotubes were observed ontop of the E-TNT layer and appeared to form a densercoverage of the Ti surface. In contrast, the fluorine-TABLE 1 Average diameter, wall thickness, and tube length oftitania nanotubes (TNT).SampleDiameter(nm)Wall thickness(nm)Tube length(µm)D-TNT 108.76 ± 2.55 30.39 ± 0.89 18.31 ± 1.93E-TNT 53.83 ± 2.42 10.27 ± 1.07 11.01 ± 0.51Abbreviations: E-TNT, ethylene glycol; D-TNT, dimethyl sulfoxide.F IGURE 4 Powder X-ray diffractometry (XRD) patterns ofD-TNT before and after annealing. Crystalline phases of D-TNTbefore annealing were anatase with small amount of rutile, butrutile phase was increased after annealing. D-TNT, dimethylsulfoxide; TNT, titania nanotubes.F IGURE 5 Powder X-ray diffractometry (XRD) patterns ofE-TNT before and after annealing. Crystalline phases of E-TNTbefore annealing were anatase with small amount of rutile as thesame as those of D-TNT. Increase of rutile phase after annealing wasalso found in D-TNT. E-TNT, ethylene glycol; D-TNT, dimethylsulfoxide; TNT, titania nanotubes.inhibiting nature of theHF/DMSO electrolyte aided in bet-ter control of the tubular morphology with pore diametersof 110 nm on the D-TNTs. As reported in the literature,33–35the surface morphology was successfully controlled usingthe synthesis conditions. The EDX results showed thatonly Ti and oxygen were present in the TNT formed usingbothHF/DMSO andHF/EG, and no fluorine was detected. 25783270, 0, Downloaded from https://ceramics.onlinelibrary.wiley.com/doi/10.1002/ces2.10214 by Cochrane Japan, Wiley Online Library on [18/03/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License6 of 9 MURALIDHAR et al.F IGURE 6 Atomic force microscopic images of (A) D-TNTs and (B) E-TNTs. Surface roughness of D-TNT shown in (A) were smootherthan that of E-TNT (B). E-TNT, ethylene glycol; D-TNT, dimethyl sulfoxide.TABLE 2 Electrical resistance and electrical conductivityvalues of Ti and titania nanotubes (TNT).SampleElectricalresistance (Ω)Electricalconductivity(S•m−1)Titanium 1.73 × 10−1 1.16 × 104D-TNT 3.89 × 108 5.33 × 10−6E-TNT 4.06 × 106 5.29 × 10−4Abbreviations: E-TNT, ethylene glycol; D-TNT, dimethyl sulfoxide.The powder XRD patterns of D- and E- TNT are shownin Figures 4 and 5, respectively. The crystalline phasesof the TNT before and after annealing were anatase (A,JCPDS 21-1272) with a small amount of rutile (R, JCPDS21-1276),36,37 the rutile phase increased after annealing inboth TNTs owing to the higher stability of rutile than theanatase and brookite phases.The surface roughness of the TNTs, characterized byAFM, is shown in Figure 6. The E-TNTs (Figure 6B) hadgreater roughness than theD-TNTs (Figure 6A). This couldbe due to the random layer-on-layer formation of TNTin the HF/EG electrolyte, which increased the surfaceroughness.The electrical resistances of Ti and TNT are listed inTable 2, where TNT has a lower electrical conductivitythan Ti. The maximum resistance of the TNT seems to besufficient for electrical polarization. Figure 7 illustratesthe results of the contact angle measurements before(0) and after polarization of the TNTs compared withbare Ti. No significant differences were observed for anysurface, except for Bare Ti. TNT formation (0-D and 0-E)decreased surface contact angle drastically to 12%–15%of that of Bare Ti. Based on the contact angle (θ) of awater droplet on a surface, θ can be classified as superhy-drophilic (θ≈0◦), hydrophilic (θ < 90◦), and hydrophobic(θ > 90◦).38 The contact angles of the 0-polarized TNTsF IGURE 7 Water contact angle of bare Ti and titaniananotubes (TNTs). No significant differences were found betweenTNT surfaces.were hydrophilic but not superhydrophilic, allowingantithrombogenic properties. From the contact anglepoint of view, polarized TNTs (P-D, N-D, P-E, and N-E)exhibited a trend of decreasing in their contact anglesas seen in other polarized surface.31 These results indi-rectly demonstrated polarization of treated layers. EachN-polarized TNT showed a decreasing trend in the contactangle in comparison to each P-polarized TNT. However,contact angles of 6◦–9◦ are still not superhydrophiliclike TiO2 after UV irradiation and did not consider to besufficient for antithrombogenic property as, similar to the0-polarized TNTs, from the viewpoint of hydrophilicity.3.2 AntithrombogenicityTypical results of the thrombus formation test are shown inFigure 8. The negative controls (glass and bare Ti) demon-strated huge thrombus formation. In contrast, thrombusformation on the TNTs was drastically suppressed. Non- 25783270, 0, Downloaded from https://ceramics.onlinelibrary.wiley.com/doi/10.1002/ces2.10214 by Cochrane Japan, Wiley Online Library on [18/03/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons LicenseMURALIDHAR et al. 7 of 9F IGURE 8 Typical thrombus formations on glass, bare Ti and titania nanotubes (TNTs). In comparison to negative controls, glass andbare Ti, thrombus formation on TNTs were suppressed drastically. Further, polarization of TNT drastically decreased thrombus formation.F IGURE 9 Relative thrombus coverage area, %, formed on glass, bare Ti and titania nanotubes (TNTs), (A) all results and (B) magnifiedresults for TNTs. N-polarization of E-TNT completely inhibited thrombus formation.polarized (0-polarized) TNTs still exhibited high throm-bus formation; however, polarization drastically decreasedthrombus formation. The image analysis results for throm-bus formation are shown in Figure 9. One-way ANOVArevealed significant differences (p < 0.00001) betweenglass and other surfaces, bare Ti and TNTs, and non-polarized (0-polarized) D-TNTs and other TNTs. Theseresults revealed that TNT formation should be effectivefor antithrombogenicity by both decreasing the contactangles and nanotopology to prevent adhesion of plateletsand/or other proteins drastically (36.2% decrease) onthe TNT. Enlargement of thrombosis results for TNTsshown in Figure 9B demonstrated a drastic decreasein thrombus formation on D-TNT at a rate of 92.4%by P-polarization and 99.7% by N-polarization, and thatof 71.7% by P-polarization and 100% by N-polarizationof E-TNT.Positively charged P-polarized TNTs attract plateletselectrostatically and are expected to form thrombi in com-parison to non-polarized (0-polarized) TNTs; however, thesurface charge and hydrophobicity of P-polarized TNTscould have a greater influence on inhibiting the attrac-tion of other important proteins for coagulation, eventuallyleading to less thrombus formationwhen compared to thatof 0-TNTs. The differences between D- and E-TNTs areconsidered to be due to differences in nanotopography,and smaller TNT could be better suited for the inhibitionof thrombus formation. Negatively charged N-polarizedTNTs showed little to no or quite small thrombus for-mation. In particular, the N-polarized E-TNTs exhibitedno thrombus formation. Based on our in vitro results, webelieve that negatively charged surfaces inhibit thrombusformation by exerting a repulsive force against nega-tively charged platelets, which is consistent with previous 25783270, 0, Downloaded from https://ceramics.onlinelibrary.wiley.com/doi/10.1002/ces2.10214 by Cochrane Japan, Wiley Online Library on [18/03/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License8 of 9 MURALIDHAR et al.studies.26 TNTs have also been applied as drug reservoirsfor antibiotics,39 growth factors,40 and antithrombogenicdrugs. In addition, the high affinity of TiO2 for cells isenhanced by polarization24 and is a good substrate forvascular endothelial cell migration and formation of thevascular endothelium to prevent long-term thrombus for-mation. Therefore, E-TNT–TiO2 is expected to be a goodcandidate for use in heart valves and other rigid devices incardiovascular surgery.4 CONCLUSIONThe Ti surface was fabricated using two types of TNTs, asper previous reports, and they were both positively andnegatively polarized. The wettability increased becauseof polarization. The antithrombogenicities of polarizedTNTs were drastically improved compared to those of non-polarized TNTs. Both nanotopographical properties andsurface charges contribute to the inhibition of thrombusformation. Negatively polarized E-TNTs demonstrated nothrombus formation in the present experiments, whichcould be useful for rigid cardiovascular devices such asartificial heart valves.ACKNOWLEDGMENTSThe authors are grateful to Profs. Akiko Nagai and Kim-ihiro Yamashita of Tokyo Medical and Dental University,Japan, for supporting the polarization of the TNTs. Theauthors would like to thank Editage (www.editage.jp) forEnglish language editing.CONFL ICT OF INTEREST STATEMENTThe authors declare no conflict of interest.ORCIDMasanoriKikuchi https://orcid.org/0000-0002-9451-8147REFERENCES1. Liu X, Yuan L, Li D, Chen G, Chen H, John LB, et al.Blood compatible materials: state of the art. J Mater Chem.2014;B2:5718–38.2. WeberM, Steinle H, Golombek S, Hann L, Schlensak C,WendelHP, et al. Blood-contacting biomaterials: in vitro evaluation ofthe hemocompatibility. Front Bioeng Biotechnol. 2018;6:993. 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Influence ofelectrical polarization on thrombogenicity of titaniananotubes. Int J Ceramic Eng Sci. 2024;e10214.https://doi.org/10.1002/ces2.10214 25783270, 0, Downloaded from https://ceramics.onlinelibrary.wiley.com/doi/10.1002/ces2.10214 by Cochrane Japan, Wiley Online Library on [18/03/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons Licensehttps://doi.org/10.1038/am.2014.34https://doi.org/10.1002/ces2.10214 Influence of electrical polarization on thrombogenicity of titania nanotubes Abstract 1 | INTRODUCTION 2 | MATERIALS AND METHODS 2.1 | Materials 2.2 | Synthesis of TNT 2.3 | Electrical polarization of TNT 2.4 | Characterization of TNT 2.5 | Antithrombogenicity evaluation 2.6 | Statistical analysis 3 | RESULTS AND DISCUSSION 3.1 | Surface characteristics of TNT 3.2 | Antithrombogenicity 4 | CONCLUSION ACKNOWLEDGMENTS CONFLICT OF INTEREST STATEMENT ORCID REFERENCES