Abstract
Theranostic platform, which is equipped with both diagnostic and therapeutic functions, is a promising approach in cancer treatment. From various nanotheranostics studied, iron oxide nanoparticles have advantages since IONPs have good biocompatibility and spatial imaging capability. This review is focused on the IONP-based nanotheranostics for cancer imaging and treatment. The most recent progress for applications of IONP nanotheranostics is summarized, which includes IONP-based diagnosis, magnetic resonance imaging (MRI), multimodal imaging, chemotherapy, hyperthermal therapy, photodynamic therapy, and gene delivery. Future perspectives and challenges are also outlined for the potential development of IONP based theranostics in clinical use.
Similar content being viewed by others
References
Tietze R, Lyer S, Dürr S, Alexiou C. Nanoparticles for cancer therapy using magnetic forces. Nanomedicine-UK, 2012, 7(3): 447–457
Zhang Z, Wang J, Chen C. Near-infrared light-mediated nanoplatforms for cancer thermo-chemotherapy and optical imaging. Advanced Materials, 2013, 25(28): 3869–3880
Yuan A, Wu J, Tang X, Zhao L, Xu F, Hu Y. Application of nearinfrared dyes for tumor imaging, photothermal, and photodynamic therapies. Journal of Pharmaceutical Sciences, 2013, 102(1): 6–28
Menon J U, Jadeja P, Tambe P, Vu K, Yuan B, Nguyen K T. Nanomaterials for photo-based diagnostic and therapeutic applications. Theranostics, 2013, 3(3): 152–166
Ryu J H, Koo H, Sun I C, Yuk S H, Choi K, Kim K, Kwon I C. Tumor-targeting multi-functional nanoparticles for theragnosis: new paradigm for cancer therapy. Advanced Drug Delivery Reviews, 2012, 64(13): 1447–1458
Xie J, Lee S, Chen X. Nanoparticle-based theranostic agents. Advanced Drug Delivery Reviews, 2010, 62(11): 1064–1079
Ho D, Sun X, Sun S. Monodisperse magnetic nanoparticles for theranostic applications. Accounts of Chemical Research, 2011, 44(10): 875–882
Sun S, Zeng H, Robinson D B, Raoux S, Rice PM, Wang S X, Li G. Monodisperse MFe2O4 (M = Fe, Co, Mn) nanoparticles. Journal of the American Chemical Society, 2004, 126(1): 273–279
Laurent S, Forge D, Port M, Roch A, Robic C, Vander Elst L, Muller R N. Magnetic iron oxide nanoparticles: synthesis, stabilization, vectorization, physicochemical characterizations, and biological applications. Chemical Reviews, 2008, 108(6): 2064–2110
Park J, Lee E, Hwang N M, Kang M, Kim S C, Hwang Y, Park J G, Noh H J, Kim J Y, Park J H, Hyeon T. One-nanometer-scale sizecontrolled synthesis of monodisperse magnetic iron oxide nanoparticles. Angewandte Chemie International Edition in English, 2005, 44(19): 2873–2877
Huang J, Zhong X, Wang L, Yang L, Mao H. Improving the magnetic resonance imaging contrast and detection methods with engineered magnetic nanoparticles. Theranostics, 2012, 2(1): 86–102
Huang Y, He S, Cao W, Cai K, Liang X J. Biomedical nanomaterials for imaging-guided cancer therapy. Nanoscale, 2012, 4(20): 6135–6149
Wang J, Huang Y, David A E, Chertok B, Zhang L, Yu F, Yang V C. Magnetic nanoparticles for MRI of brain tumors. Current Pharmaceutical Biotechnology, 2012, 13(12): 2403–2416
Psimadas D, Baldi G, Ravagli C, Comes Franchini M, Locatelli E, Innocenti C, Sangregorio C, Loudos G. Comparison of the magnetic, radiolabeling, hyperthermic and biodistribution properties of hybrid nanoparticles bearing CoFe2O4 and Fe3O4 metal cores. Nanotechnology, 2014, 25(2): 025101
Lee S H, Kim B H, Na H B, Hyeon T. Paramagnetic inorganic nanoparticles as T1 MRI contrast agents. Wiley Interdisciplinary Reviews: Nanomedicine and Nanobiotechnology, 2014, 6(2): 196–209
Xiao N, Gu W, Wang H, Deng Y, Shi X, Ye L. T1-T2 dual-modal MRI of brain gliomas using PEGylated Gd-doped iron oxide nanoparticles. Journal of Colloid and Interface Science, 2014, 417: 159–165
Ragheb R R T, Kim D, Bandyopadhyay A, Chahboune H, Bulutoglu B, Ezaldein H, Criscione J M, Fahmy T M. Induced clustered nanoconfinement of superparamagnetic iron oxide in biodegradable nanoparticles enhances transverse relaxivity for targeted theranostics. Magnetic Resonance in Medicine, 2013, 70(6): 1748–1760
Balasubramaniam S, Kayandan S, Lin Y N, Kelly D F, House M J, Woodward R C, St Pierre T G, Riffle J S, Davis RM. Toward design of magnetic nanoparticle clusters stabilized by biocompatible diblock copolymers for T?-weighted MRI contrast. Langmuir, 2014, 30(6): 1580–1587
Tähkä S, Laiho A, Kostiainen M A. Diblock-copolymer-mediated self-assembly of protein-stabilized iron oxide nanoparticle clusters for magnetic resonance imaging. Chemistry, 2014, 20(10): 2718–2722
Lee G Y, Qian W P, Wang L, Wang Y A, Staley C A, Satpathy M, Nie S, Mao H, Yang L. Theranostic nanoparticles with controlled release of gemcitabine for targeted therapy and MRI of pancreatic cancer. ACS Nano, 2013, 7(3): 2078–2089
Zhang L, Zhong X, Wang L, Chen H, Wang Y A, Yeh J, Yang L, Mao H. T1-weighted ultrashort echo time method for positive contrast imaging of magnetic nanoparticles and cancer cells bound with the targeted nanoparticles. Journal of Magnetic Resonance Imaging, 2011, 33(1): 194–202
Xie J, Liu G, Eden H S, Ai H, Chen X. Surface-engineered magnetic nanoparticle platforms for cancer imaging and therapy. Accounts of Chemical Research, 2011, 44(10): 883–892
Lin X, Xie J, Niu G, Zhang F, Gao H, Yang M, Quan Q, Aronova M A, Zhang G, Lee S, Leapman R, Chen X. Chimeric ferritin nanocages for multiple function loading and multimodal imaging. Nano Letters, 2011, 11(2): 814–819
Chen Y C, Wen S, Shang S A, Cui Y, Luo B, Teng G J. Magnetic resonance and near-infrared imaging using a novel dual-modality nano-probe for dendritic cell tracking in vivo. Cytotherapy, 2014, 16(5): 699–710
Lee H Y, Li Z, Chen K, Hsu A R, Xu C, Xie J, Sun S, Chen X. PET/MRI dual-modality tumor imaging using arginine-glycine-aspartic (RGD)-conjugated radiolabeled iron oxide nanoparticles. Journal of Nuclear Medicine, 2008, 49(8): 1371–1379
Xie J, Chen K, Huang J, Lee S, Wang J, Gao J, Li X, Chen X. PET/NIRF/MRI triple functional iron oxide nanoparticles. Biomaterials, 2010, 31(11): 3016–3022
Key J, Cooper C, Kim A Y, Dhawan D, Knapp D W, Kim K, Park J H, Choi K, Kwon I C, Park K, Leary J F. In vivo NIRF and MR dualmodality imaging using glycol chitosan nanoparticles. Journal of Controlled Release, 2012, 163(2): 249–255
Sun Z, Huang P, Tong G, Lin J, Jin A, Rong P, Zhu L, Nie L, Niu G, Cao F, Chen X. VEGF-loaded graphene oxide as theranostics for multi-modality imaging-monitored targeting therapeutic angiogenesis of ischemic muscle. Nanoscale, 2013, 5(15): 6857–6866
Key J, Aryal S, Gentile F, Ananta J S, Zhong M, Landis M D, Decuzzi P. Engineering discoidal polymeric nanoconstructs with enhanced magneto-optical properties for tumor imaging. Biomaterials, 2013, 34(21): 5402–5410
Cao C, Wang X, Cai Y, Sun L, Tian L, Wu H, He X, Lei H, Liu W, Chen G, Zhu R, Pan Y. Targeted in vivo imaging of microscopic tumors with ferritin-based nanoprobes across biological barriers. Advanced Materials, 2014, 26(16): 2566–2571
Zhang Y, Zhang B, Liu F, Luo J, Bai J. In vivo tomographic imaging with fluorescence and MRI using tumor-targeted dual-labeled nanoparticles. International Journal of Nanomedicine, 2014, 9: 33–41
Zou P, Chen H, Paholak H J, Sun D. Noninvasive fluorescence resonance energy transfer imaging of in vivo premature drug release from polymeric nanoparticles. Molecular Pharmaceutics, 2013, 10(11): 4185–4194
Niu C, Wang Z, Lu G, Krupka T M, Sun Y, You Y, Song W, Ran H, Li P, Zheng Y. Doxorubicin loaded superparamagnetic PLGA-iron oxide multifunctional microbubbles for dual-mode US/MR imaging and therapy of metastasis in lymph nodes. Biomaterials, 2013, 34(9): 2307–2317
Chertok B, David A E, Yang V C. Brain tumor targeting of magnetic nanoparticles for potential drug delivery: effect of administration route and magnetic field topography. Journal of Controlled Release, 2011, 155(3): 393–399
Ye F, Barrefelt A, Asem H, Abedi-Valugerdi M, El-Serafi I, Saghafian M, Abu-Salah K, Alrokayan S, Muhammed M, Hassan M. Biodegradable polymeric vesicles containing magnetic nanoparticles, quantum dots and anticancer drugs for drug delivery and imaging. Biomaterials, 2014, 35(12): 3885–3894
Javid A, Ahmadian S, Saboury A A, Kalantar SM, Rezaei-Zarchi S, Shahzad S. Biocompatible APTES-PEG modified magnetite nanoparticles: Effective carriers of antineoplastic agents to ovarian cancer. Applied Biochemistry and Biotechnology, 2014, 173(1): 36–54
Zou P, Yu Y, Wang Y A, Zhong Y, Welton A, Galbán C, Wang S, Sun D. Superparamagnetic iron oxide nanotheranostics for targeted cancer cell imaging and pH-dependent intracellular drug release. Molecular Pharmaceutics, 2010, 7(6): 1974–1984
El-Dakdouki M H, Zhu D C, El-Boubbou K, Kamat M, Chen J, Li W, Huang X. Development of multifunctional hyaluronan-coated nanoparticles for imaging and drug delivery to cancer cells. Biomacromolecules, 2012, 13(4): 1144–1151
Zhang J, Shin M C, Yang V C. Magnetic targeting of novel heparinized iron oxide nanoparticles evaluated in a 9L-glioma mouse model. Pharmaceutical Research, 2014, 31(3): 579–592
Zhang J, Shin M C, David A E, Zhou J, Lee K, He H, Yang V C. Long-circulating heparin-functionalized magnetic nanoparticles for potential application as a protein drug delivery platform. Molecular Pharmaceutics, 2013, 10(10): 3892–3902
Chiang WH, Huang WC, Chang CW, Shen M Y, Shih Z F, Huang Y F, Lin S C, Chiu H C. Functionalized polymersomes with outlayered polyelectrolyte gels for potential tumor-targeted delivery of multimodal therapies and MR imaging. Journal of Controlled Release, 2013, 168(3): 280–288
Gupta A K, Gupta M. Synthesis and surface engineering of iron oxide nanoparticles for biomedical applications. Biomaterials, 2005, 26(18): 3995–4021
Ito A, Shinkai M, Honda H, Kobayashi T. Medical application of functionalized magnetic nanoparticles. Journal of Bioscience and Bioengineering, 2005, 100(1): 1–11
Chen H W, Burnett J, Zhang F X, Zhang J M, Paholak H, Sun D X. Highly crystallized iron oxide nanoparticles as effective and biodegradable mediators for photothermal cancer therapy. Journal of Materials Chemistry B, 2014, 2(7): 757–765
Maier-Hauff K, Rothe R, Scholz R, Gneveckow U, Wust P, Thiesen B, Feussner A, von Deimling A, Waldoefner N, Felix R, Jordan A. Intracranial thermotherapy using magnetic nanoparticles combined with external beam radiotherapy: results of a feasibility study on patients with glioblastoma multiforme. Journal of Neuro-Oncology, 2007, 81(1): 53–60
Béalle G, Di Corato R, Kolosnjaj-Tabi J, Dupuis V, Clément O, Gazeau F, Wilhelm C, Ménager C. Ultra magnetic liposomes for MR imaging, targeting, and hyperthermia. Langmuir, 2012, 28(32): 11834–11842
Johannsen M, Thiesen B, Wust P, Jordan A. Magnetic nanoparticle hyperthermia for prostate cancer. International Journal of Hyperthermia, 2010, 26(8): 790–795
Silva A C, Oliveira T R, Mamani J B, Malheiros S M, Malavolta L, Pavon L F, Sibov T T, Amaro E Jr, Tannús A, Vidoto E L, Martins M J, Santos R S, Gamarra L F. Application of hyperthermia induced by superparamagnetic iron oxide nanoparticles in glioma treatment. International Journal of Nanomedicine, 2011, 6: 591–603
Laurent S, Dutz S, Häfeli U O, Mahmoudi M. Magnetic fluid hyperthermia: focus on superparamagnetic iron oxide nanoparticles. Advances in Colloid and Interface Science, 2011, 166(1–2): 8–23
Chiang W H, Ho V T, Chen H H, Huang W C, Huang Y F, Lin S C, Chern C S, Chiu H C. Superparamagnetic hollow hybrid nanogels as a potential guidable vehicle system of stimuli-mediated MR imaging and multiple cancer therapeutics. Langmuir, 2013, 29(21): 6434–6443
Kievit F M, Zhang M. Surface engineering of iron oxide nanoparticles for targeted cancer therapy. Accounts of Chemical Research, 2011, 44(10): 853–862
Nie X, Chen C. Au nanostructures: an emerging prospect in cancer theranostics. Science China Life Sciences, 2012, 55(10): 872–883
Choi W I, Sahu A, Kim Y H, Tae G. Photothermal cancer therapy and imaging based on gold nanorods. Annals of Biomedical Engineering, 2012, 40(2): 534–546
Thakare V S, Das M, Jain A K, Patil S, Jain S. Carbon nanotubes in cancer theragnosis. Nanomedicine, 2010, 5(8): 1277–1301
Feng L, Wu L, Qu X. New horizons for diagnostics and therapeutic applications of graphene and graphene oxide. Advanced Materials, 2013, 25(2): 168–186
Sahu A, Choi W I, Lee J H, Tae G. Graphene oxide mediated delivery of methylene blue for combined photodynamic and photothermal therapy. Biomaterials, 2013, 34(26): 6239–6248
Ke H, Wang J, Tong S, Jin Y, Wang S, Qu E, Bao G, Dai Z. Gold nanoshelled liquid perfluorocarbon magnetic nanocapsules: a nanotheranostic platform for bimodal ultrasound/magnetic resonance imaging guided photothermal tumor ablation. Theranostics, 2014, 4(1): 12–23
Chen W, Ayala-Orozco C, Biswal N C, Perez-Torres C, Bartels M, Bardhan R, Stinnet G, Liu X D, Ji B, Deorukhkar A, Brown L V, Guha S, Pautler R G, Krishnan S, Halas N J, Joshi A. Targeting pancreatic cancer with magneto-fluorescent theranostic gold nanoshells. Nanomedicine, Posted online on September 24, 2013, Pages:1–14
Wang X, Liu H, Chen D, Meng X, Liu T, Fu C, Hao N, Zhang Y, Wu X, Ren J, Tang F. Multifunctional Fe3O4@P(St/MAA) @chitosan@Au core/shell nanoparticles for dual imaging and photothermal therapy. ACS Applied Materials & Interfaces, 2013, 5(11): 4966–4971
Melancon M P, Lu W, Zhong M, Zhou M, Liang G, Elliott A M, Hazle J D, Myers J N, Li C, Stafford R J. Targeted multifunctional gold-based nanoshells for magnetic resonance-guided laser ablation of head and neck cancer. Biomaterials, 2011, 32(30): 7600–7608
Fan Z, Shelton M, Singh A K, Senapati D, Khan S A, Ray P C. Multifunctional plasmonic shell-magnetic core nanoparticles for targeted diagnostics, isolation, and photothermal destruction of tumor cells. ACS Nano, 2012, 6(2): 1065–1073
Cheng L, Yang K, Li Y, Chen J, Wang C, Shao M, Lee S T, Liu Z. Facile preparation of multifunctional upconversion nanoprobes for multimodal imaging and dual-targeted photothermal therapy. Angewandte Chemie International Edition in English, 2011, 50(32): 7385–7390
Hu Y, Meng L, Niu L, Lu Q. Facile synthesis of superparamagnetic Fe3O4@polyphosphazene@Au shells for magnetic resonance imaging and photothermal therapy. ACS Applied Materials & Interfaces, 2013, 5(11): 4586–4591
Ohulchanskyy T Y, Kopwitthaya A, Jeon M, Guo M, Law W C, Furlani E P, Kim C, Prasad P N. Phospholipid micelle-based magneto-plasmonic nanoformulation for magnetic field-directed, imaging-guided photo-induced cancer therapy. Nanomedicine-UK, 2013, 9(8): 1192–1202
Wang C, Irudayaraj J. Multifunctional magnetic-optical nanoparticle probes for simultaneous detection, separation, and thermal ablation of multiple pathogens. Small, 2010, 6(2): 283–289
Kirui D K, Khalidov I, Wang Y, Batt C A. Targeted near-IR hybrid magnetic nanoparticles for in vivo cancer therapy and imaging. Nanomedicine-UK, 2013, 9(5): 702–711
Kirui D K, Rey D A, Batt C A. Gold hybrid nanoparticles for targeted phototherapy and cancer imaging. Nanotechnology, 2010, 21(10): 105105
Shi X, Gong H, Li Y, Wang C, Cheng L, Liu Z. Graphene-based magnetic plasmonic nanocomposite for dual bioimaging and photothermal therapy. Biomaterials, 2013, 34(20): 4786–4793
Yang K, Hu L, Ma X, Ye S, Cheng L, Shi X, Li C, Li Y, Liu Z. Multimodal imaging guided photothermal therapy using functionalized graphene nanosheets anchored with magnetic nanoparticles. Advanced Materials, 2012, 24(14): 1868–1872
Ma Y, Tong S, Bao G, Gao C, Dai Z. Indocyanine green loaded SPIO nanoparticles with phospholipid-PEG coating for dual-modal imaging and photothermal therapy. Biomaterials, 2013, 34(31): 7706–7714
Wang C, Xu H, Liang C, Liu Y, Li Z, Yang G, Cheng L, Li Y, Liu Z. Iron oxide @ polypyrrole nanoparticles as a multifunctional drug carrier for remotely controlled cancer therapy with synergistic antitumor effect. ACS Nano, 2013, 7(8): 6782–6795
Shen S, Kong F, Guo X, Wu L, Shen H, Xie M, Wang X, Jin Y, Ge Y. CMCTS stabilized Fe3O4 particles with extremely low toxicity as highly efficient near-infrared photothermal agents for in vivo tumor ablation. Nanoscale, 2013, 5(17): 8056–8066
Chu M, Shao Y, Peng J, Dai X, Li H, Wu Q, Shi D. Near-infrared laser light mediated cancer therapy by photothermal effect of Fe3O4 magnetic nanoparticles. Biomaterials, 2013, 34(16): 4078–4088
Levy M, Luciani N, Alloyeau D, Elgrabli D, Deveaux V, Pechoux C, Chat S, Wang G, Vats N, Gendron F, Factor C, Lotersztajn S, Luciani A, Wilhelm C, Gazeau F. Long term in vivo biotransformation of iron oxide nanoparticles. Biomaterials, 2011, 32(16): 3988–3999
Gu L, Fang R H, Sailor M J, Park J H. In vivo clearance and toxicity of monodisperse iron oxide nanocrystals. ACS Nano, 2012, 6(6): 4947–4954
Tassa C, Shaw S Y, Weissleder R. Dextran-coated iron oxide nanoparticles: a versatile platform for targeted molecular imaging, molecular diagnostics, and therapy. Accounts of Chemical Research, 2011, 44(10): 842–852
Yoon H J, Lim T G, Kim J H, Cho YM, Kim Y S, Chung U S, Kim J H, Choi B W, Koh W G, Jang W D. Fabrication of multifunctional layer-by-layer nanocapsules toward the design of theragnostic nanoplatform. Biomacromolecules, 2014, 15(4): 1382–1389
Shi J, Yu X, Wang L, Liu Y, Gao J, Zhang J, Ma R, Liu R, Zhang Z. PEGylated fullerene/iron oxide nanocomposites for photodynamic therapy, targeted drug delivery and MR imaging. Biomaterials, 2013, 34(37): 9666–9677
Huang G, Chen H, Dong Y, Luo X, Yu H, Moore Z, Bey E A, Boothman D A, Gao J. Superparamagnetic iron oxide nanoparticles: amplifying ROS stress to improve anticancer drug efficacy. Theranostics, 2013, 3(2): 116–126
Taratula O, Garbuzenko O, Savla R, Wang Y A, He H, Minko T. Multifunctional nanomedicine platform for cancer specific delivery of siRNA by superparamagnetic iron oxide nanoparticles-dendrimer complexes. Current Drug Delivery, 2011, 8(1): 59–69
Tang C, Russell P J, Martiniello-Wilks R, Rasko J E, Khatri A. Concise review: Nanoparticles and cellular carriers-allies in cancer imaging and cellular gene therapy? Stem Cells (Dayton, Ohio), 2010, 28(9): 1686–1702
Medarova Z, Pham W, Farrar C, Petkova V, Moore A. In vivo imaging of siRNA delivery and silencing in tumors. Nature Medicine, 2007, 13(3): 372–377
Chen J, Zhu S, Tong L, Li J, Chen F, Han Y, Zhao M, Xiong W. Superparamagnetic iron oxide nanoparticles mediated (131)IhVEGF siRNA inhibits hepatocellular carcinoma tumor growth in nude mice. BMC Cancer, 2014, 14(1): 114
Turcheniuk K, Tarasevych A V, Kukhar V P, Boukherroub R, Szunerits S. Recent advances in surface chemistry strategies for the fabrication of functional iron oxide based magnetic nanoparticles. Nanoscale, 2013, 5(22): 10729–10752
Hu S H, Hsieh T Y, Chiang C S, Chen P J, Chen Y Y, Chiu T L, Chen S Y. Surfactant-free, lipo-polymersomes stabilized by iron oxide nanoparticles/polymer interlayer for synergistically targeted and magnetically guided gene delivery. Advanced Healthcare Materials, 2014, 3(2): 273–282
Jiang S, Eltoukhy A A, Love K T, Langer R, Anderson D G. Lipidoid-coated iron oxide nanoparticles for efficient DNA and siRNA delivery. Nano Letters, 2013, 13(3): 1059–1064
Yathindranath V, Sun Z, Worden M, Donald L J, Thliveris J A, Miller D W, Hegmann T. One-pot synthesis of iron oxide nanoparticles with functional silane shells: a versatile general precursor for conjugations and biomedical applications. Langmuir, 2013, 29(34): 10850–10858
Wang C, Ravi S, Martinez G V, Chinnasamy V, Raulji P, Howell M, Davis Y, Mallela J, Seehra M S, Mohapatra S. Dual-purpose magnetic micelles for MRI and gene delivery. Journal of Controlled Release, 2012, 163(1): 82–92
He H, David A, Chertok B, Cole A, Lee K, Zhang J, Wang J, Huang Y, Yang V C. Magnetic nanoparticles for tumor imaging and therapy: a so-called theranostic system. Pharmaceutical Research, 2013, 30(10): 2445–2458
Author information
Authors and Affiliations
Corresponding author
Additional information
Dr. Duxin Sun is a professor in the Department of Pharmaceutical Sciences, University of Michigan. He has joint appointment in the Chemical Biology program, and the Interdisciplinary Medicinal Chemistry program. He serves as the director of Pharmacokinetics (PK) Core and is a member of University of Michigan’s Comprehensive Cancer Center. Also, he has served as chair of the PPB (Physical Pharmacy and Biopharmaceutics) section in AAPS (American Association of Pharmaceutical Scientists); vice president of the American Chinese Pharmaceutical Association (ACPA). Dr. Sun has served on study sections for many grant agencies, such as the NIH, FDA, Cancer Research UK, French National Research Agency, and Italian Ministry of Health.
Rights and permissions
About this article
Cite this article
Ren, X., Chen, H., Yang, V. et al. Iron oxide nanoparticle-based theranostics for cancer imaging and therapy. Front. Chem. Sci. Eng. 8, 253–264 (2014). https://doi.org/10.1007/s11705-014-1425-y
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11705-014-1425-y