Topics in Current Chemistry

, 374:69 | Cite as

Radiation Engineering of Multifunctional Nanogels

Review
Part of the following topical collections:
  1. Applications of Radiation Chemistry

Abstract

Nanogels combine the favourable properties of hydrogels with those of colloids. They can be soft and conformable, stimuli-responsive and highly permeable, and can expose a large surface with functional groups for conjugation to small and large molecules, and even macromolecules. They are among the very few systems that can be generated and used as aqueous dispersions. Nanogels are emerging materials for targeted drug delivery and bio-imaging, but they have also shown potential for water purification and in catalysis. The possibility of manufacturing nanogels with a simple process and at relatively low cost is a key criterion for their continued development and successful application. This paper highlights the most important structural features of nanogels related to their distinctive properties, and briefly presents the most common manufacturing strategies. It then focuses on synthetic approaches that are based on the irradiation of dilute aqueous polymer solutions using high-energy photons or electron beams. The reactions constituting the basis for nanogel formation and the approaches for controlling particle size and functionality are discussed in the context of a qualitative analysis of the kinetics of the various reactions.

Keywords

Nanogels Synthesis of nanoparticles Radiation processing Crosslinking 

References

  1. 1.
    IUPAC (1997) Compendium of Chemical Terminology, 2nd ed. (the “Gold Book”). Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford. XML on-line corrected version: http://goldbook.iupac.org (2006) created by M. Nic, J. Jirat, B. Kosata; updates compiled by A. Jenkins
  2. 2.
    Motornov M, Roiter Y, Tokarev I, Minko S (2010) Stimuli-responsive nanoparticles, nanogels and capsules for integrated multifunctional intelligent systems. Prog Polym Sci 35:174–211CrossRefGoogle Scholar
  3. 3.
    Ricka J, Tanaka T (1984) Swelling of ionic gels: quantitative performance of the Donnan theory. Macromolecules 17:2916–2921CrossRefGoogle Scholar
  4. 4.
    Akiyoshi K, Kobayashi S, Shichibe S, Mix D, Baudys M, Kim SW, Sunamoto J (1998) Self-assembled hydrogel nanoparticle of cholesterol-bearing pullulan as a carrier of protein drugs: complexation and stabilization of insulin. J Control Release 54(3):313–320CrossRefGoogle Scholar
  5. 5.
    Chen Y, Ballard N, Bon SAF (2013) Waterborne polymer nanogels non-covalently crosslinked by multiple hydrogen bond arrays. Polym Chem 4:387–392CrossRefGoogle Scholar
  6. 6.
    Lim C-K, Singh A, Heo J, Kim D, Lee KE, Jeon H, Koh J, Kwon I-C, Kim S (2013) Gadolinium-coordinated elastic nanogels for in vivo tumor targeting and imaging. Biomaterials 34:6846–6852CrossRefGoogle Scholar
  7. 7.
    López-León T, Carvalho ELS, Seijo B, Ortega-Vinuesa JL, Bastos-González D (2005) Physicochemical characterization of chitosan nanoparticles: electrokinetic and stability behaviour. J Colloid Interf Sci 283:344–351CrossRefGoogle Scholar
  8. 8.
    Israelachvili JN (2011) Intermolecular and surface forces, 3rd edn. Academic Press, San DiegoGoogle Scholar
  9. 9.
    Picone P, Ditta LA, Sabatino MA, Militello V, San Biagio PL, Di Giacinto ML, Cristaldi L, Nuzzo D, Dispenza C, Giacomazza D, Di Carlo M (2016) Ionizing radiation-engineered nanogels as insulin nanocarriers for the development of a new strategy for the treatment of Alzheimer’s disease. Biomaterials 80:179–194CrossRefGoogle Scholar
  10. 10.
    Brown W, Nicolai T (1993) Dynamic light scattering: the method and some applications. Ed. Clarendon Press, OxfordGoogle Scholar
  11. 11.
    Wyatt PJ (1993) Light scattering and the absolute characterization of macromolecules. Anal Chim Acta 272:1–40CrossRefGoogle Scholar
  12. 12.
    Maya S, Sarmento B, Nair A, Rejinold NS, Nair SV, Jayakumar R (2013) Smart stimuli sensitive nanogels in cancer drug delivery and imaging: a review. Curr Pharm Des 19(41):7203–7218CrossRefGoogle Scholar
  13. 13.
    Shen X, Zhang L, Jiang X, Hu Y, Guo J (2007) Reversible surface switching of nanogel triggered by external stimuli. Angew Chem Int Ed 46:7104–7107CrossRefGoogle Scholar
  14. 14.
    Du J-Z, Sun T-M, Song W-J, Wu J, Wang JA (2010) Tumor-acidity-activated charge-conversional nanogel as an intelligent vehicle for promoted tumoral-cell uptake and drug delivery. Angew Chem Int Ed 49:3621–3626CrossRefGoogle Scholar
  15. 15.
    Zha L, Banik B, Alexis F (2011) Stimulus responsive nanogels for drug delivery. Soft Matter 7:5908–5916CrossRefGoogle Scholar
  16. 16.
    Bromberg LE, Ron ES (1998) Temperature-responsive gels and thermogelling polymer matrices for protein and peptide delivery. Adv Drug Deliv Rev 31:197–221CrossRefGoogle Scholar
  17. 17.
    Gandhi SS, Yan H, Kim C (2014) Thermoresponsive gelatin nanogels. ACS Macro Lett 3:1210–1214CrossRefGoogle Scholar
  18. 18.
    Xu S, Olenyuk BZ, Okamoto CT, Hamm-Alvarez SF (2013) Targeting receptor-mediated endocytotic pathways with nanoparticles: rationale and advances. Adv Drug Deliv Rev 65(1):121–138CrossRefGoogle Scholar
  19. 19.
    Lei Ye (ed) (2013) Molecular imprinting: principles and applications of micro- and nanostructured polymers. CRC PressGoogle Scholar
  20. 20.
    Carboni D, Flavin K, Servant A, Gouverneur V, Resmini M (2008) The first example of molecularly imprinted nanogels with aldolase type I activity. Chemistry 14(23):7059–7065Google Scholar
  21. 21.
    Pan G, Guo Q, Cao C, Yang H, Li B (2013) Thermo-responsive molecularly imprinted nanogels for specific recognition and controlled release of proteins. Soft Matter 9:3840–3850CrossRefGoogle Scholar
  22. 22.
    Varga I, Szalai I, Mészaros R, Gilányi T (2006) Pulsating pH-responsive nanogels. J Phys Chem B 110(41):20297–20301CrossRefGoogle Scholar
  23. 23.
    Sakai T, Yoshida R (2004) Self-oscillating nanogel particles. Langmuir 20(4):1036–1038CrossRefGoogle Scholar
  24. 24.
    Wu W, Zhou S (2010) Hybrid micro-/nanogels for optical sensing and intracellular imaging. Nano Rev 1:5730CrossRefGoogle Scholar
  25. 25.
    Kondo K, Kaji N, Toita S, Okamoto Y, Tokeshi M, Akiyoshi K, Baba Y (2010) DNA separation by cholesterol-bearing pullulan nanogels. Biomicrofluidics 4(3):32210–32218CrossRefGoogle Scholar
  26. 26.
    Akl MA, Sarhan AA, Shoueir KR, Atta AM (2013) Application of crosslinked ionic poly(vinyl alcohol)nanogel as adsorbents for water treatment. J Dispers Sci Technol 34(10):1399–1408CrossRefGoogle Scholar
  27. 27.
    Resmini M, Flavin K, Carboni D (2012) Microgels and nanogels with catalytic activity. Top Curr Chem 325:307–342CrossRefGoogle Scholar
  28. 28.
    Kuroda K, Fujimoto K, Sunamoto J, Akiyoshi K (2002) Hierarchical self-assembly of hydrophobically modified pullulan in water: gelation by networks of nanoparticles. Langmuir 18(10):3780–3786CrossRefGoogle Scholar
  29. 29.
    Nakai T, Hirakura T, Sakurai Y, Shimoboji T, Ishigai M, Akiyoshi K (2012) Injectable hydrogel for sustained protein release by salt-induced association of hyaluronic acid nanogel. Macromol Biosci 12(4):475–483CrossRefGoogle Scholar
  30. 30.
    Li Y, Ye Z, Shen L, Xu Y, Zhu A, Wu P, An Z (2016) Formation of multidomain hydrogels via thermally induced assembly of pisa-generated triblock terpolymer nanogels. Macromolecules 49(8):3038–3048CrossRefGoogle Scholar
  31. 31.
    Xia L-W, Xie R, Ju X-J, Wang W, Chen Q, Chu L-Y (2013) Nano-structured smart hydrogels with rapid response and high elasticity. Nat Commun 4:2226–2236Google Scholar
  32. 32.
    Luo F, Xie R, Liu Z, Ju X-J, Wang W, Lin S, Chu L-Y (2015) Smart gating membranes with in situ self-assembled responsive nanogels as functional gates. Sci Rep 5:14708–14721CrossRefGoogle Scholar
  33. 33.
    Reese CE, Mikhonin AV, Kamenjicki M, Tikhonov A, Asher SA (2004) Nanogel nanosecond photonic crystal optical switching. J Am Chem Soc 126(5):1493–1496CrossRefGoogle Scholar
  34. 34.
    Tian L, Liu K-K, Fei M, Tadepalli S, Cao S, Geldmeier JA, Tsukruk VV, Singamaneni S (2016) Plasmonic nanogels for unclonable optical tagging. ACS Appl Mater Interfaces 8(6):4031–4041CrossRefGoogle Scholar
  35. 35.
    Saez-Martinez V, Olalde B, Juan MJ, Jurado MJ, Garagorri N, Obieta I (2010) Novel bioactive scaffolds incorporating nanogels as potential drug eluting devices. J Nanosci Nanotechnol 10(4):2826–2832CrossRefGoogle Scholar
  36. 36.
    Oh JK, Drumright R, Siegwart DJ, Matyjaszewski K (2008) The development of microgel/nanogels for drug delivery applications. Prog Polym Sci 33(4):448–477CrossRefGoogle Scholar
  37. 37.
    Kabanov AV, Vinogradov SV (2009) Nanogels as pharmaceutical carriers: finite networks of infinite capabilities. Angew Chem Int Ed Engl 48(30):5418–5429CrossRefGoogle Scholar
  38. 38.
    Sanson N, Rieger J (2010) Synthesis of nanogels/microgels by conventional and controlled radical crosslinking copolymerization. Polym Chem 1:965–977CrossRefGoogle Scholar
  39. 39.
    Zhang X, Malhotra S, Molina M, Haag R (2015) Micro- and nanogels with labile crosslinks—from synthesis to biomedical applications. Chem Soc Rev 44:1948–1973CrossRefGoogle Scholar
  40. 40.
    Ulański P, Rosiak JM (2004) Polymeric Nano/Microgels. In: Nalwa HS (ed) Encyclopedia of nanoscience and Nanotechnology, vol VIII, pp 845–871, ISBN 1-58883-001-2. American Scientific Publishers, Stevenson RanchGoogle Scholar
  41. 41.
    Lipomi DJ, Martinez RV, Cademartiri L, Whitesides GM (2012) Soft lithographic approaches to nanofabrication, chapter 7.11. In: Matyjaszewski K and Möller M (eds) Polymer science: a comprehensive reference, 1st edn. Elsevier, Amsterdam, pp 211–231Google Scholar
  42. 42.
    Rolland JP, Maynor BW, Euliss LE, Exner AE, Denison GM, DeSimone JM (2005) Direct fabrication and harvesting of monodisperse, shape-specific nanobiomaterials. J Am Chem Soc 127(28):10096–10100CrossRefGoogle Scholar
  43. 43.
    Omichi M, Marui H, Takano K, Tsukuda S, Sugimoto M, Kuwabata S, Seki S (2012) Temperature-responsive one-dimensional nanogels formed by the cross-linker-aided single particle nanofabrication technique. ACS Appl Mater Interfaces 4(10):5492–5497CrossRefGoogle Scholar
  44. 44.
    Zhang H, Tumarkin E, Sullan RMA, Walker GC, Kumacheva E (2007) Exploring microfluidic routes to microgels of biological polymers. Macromol Rapid Commun 28(5):527–538CrossRefGoogle Scholar
  45. 45.
    Bazban-Shotorbani S, Dashtimoghadam E, Karkhaneh A, Hasani-Sadrabadi MM, Jacob KI (2016) Microfluidic directed synthesis of alginate nanogels with tunable pore size for efficient protein delivery. Langmuir 32(19):4996–5003CrossRefGoogle Scholar
  46. 46.
    Nesvadba P (2012) Radical polymerization in industry. In: Chatgilialoglu C, Studer A (eds) Encyclopedia of radicals in chemistry, biology and materials. John Wiley & Sons, Inc, New YorkGoogle Scholar
  47. 47.
    Oh JK, Bencherif SA, Matyjaszewski K (2009) Polymer atom transfer radical polymerization in inverse miniemulsion: a versatile route toward preparation and functionalization of microgels/nanogels for targeted drug delivery applications. Polymer 50(19):4407–4423CrossRefGoogle Scholar
  48. 48.
    Medeiros SF, Santos AM, Fessi H, Elaissari A (2010) Synthesis of biocompatible and thermally sensitive poly(N-vinylcaprolactam) nanogels via inverse miniemulsion polymerization: effect of the surfactant concentration. J Polym Sci A Polym Chem 48:3932–3941CrossRefGoogle Scholar
  49. 49.
    Klinger D, Aschenbrenner EM, Weiss KC, Landfester K (2012) Enzymatically degradable nanogels by inverse miniemulsion copolymerization of acrylamide with dextran methacrylates as crosslinkers. Polym Chem 3:204–216CrossRefGoogle Scholar
  50. 50.
    Sarika PR, James NR (2015) Preparation and characterisation of gelatin–gum arabic aldehyde nanogels via inverse miniemulsion technique. Int J Biol Macromol 76:181–187CrossRefGoogle Scholar
  51. 51.
    Blackburn WH, Lyon LA (2008) Size controlled synthesis of monodispersed, core/shell nanogels. Colloid Polym Sci 286(5):563–569CrossRefGoogle Scholar
  52. 52.
    Muller AHE, Matyjaszewski K (eds) (2010) Controlled and living polymerizations from mechanisms to applications. Wiley-VCH Verlag GmbH, WeinheimGoogle Scholar
  53. 53.
    Destarac M (2010) Controlled Radical Polymerization: industrial stakes, obstacles and achievements. Macromol React Eng 4(3–4):165–179CrossRefGoogle Scholar
  54. 54.
    Lupitskyya R, Minko S (2010) Robust synthesis of nanogel particles by an aggregation-crosslinking method. Soft Matter 6:4396–4402CrossRefGoogle Scholar
  55. 55.
    Li Y, Maciel D, Rodrigues J, Shi X, Tomás H (2015) Biodegradable polymer nanogels for drug/nucleic acid delivery. Chem Rev 115(16):8564–8608CrossRefGoogle Scholar
  56. 56.
    Lee JI, Kim HS, Yoo HS (2009) DNA nanogels composed of chitosan and Pluronic with thermo-sensitive and photo-crosslinking properties. Int J Pharma 373(1–2):93–99CrossRefGoogle Scholar
  57. 57.
    Zubareva A, Ilyina A, Prokhorov A, Kurek D, Efremov M, Varlamov V, Senel S, Ignatyev P, Svirshchevskaya E (2013) Characterization of protein and peptide binding to nanogels formed by differently charged chitosan derivatives. Molecules 18(7):7848–7864CrossRefGoogle Scholar
  58. 58.
    Siqueira Franco Picone C, Lopes Cunha R (2013) Chitosan–gellan electrostatic complexes: influence of preparation conditions and surfactant presence. Carbohydr Polym 94(1):695–703CrossRefGoogle Scholar
  59. 59.
    Hiramoto S, Amano Y, Sato M, Suzuki Y, Shinohara M, Emoto S, Yamaguchi H, Ishigami H, Sakai Y, Kitayama J, Ito T (2016) Production of cisplatin-incorporating hyaluronan nanogels via chelating ligand-metal coordination. Bioconjug Chem 27(3):504–508CrossRefGoogle Scholar
  60. 60.
    Vo CD, Kuckling D, Adler H-JP, Schonhoff M (2002) Preparation of thermosensitive nanogels by photo-cross-linking. Colloid Polym Sci 280:400–409CrossRefGoogle Scholar
  61. 61.
    Dispenza C, Grimaldi N, Sabatino MA, Soroka IL, Jonsson M (2015) Radiation-engineered functional nanoparticles in aqueous system. J Nanosci Nanotech 15(5):3445–3467CrossRefGoogle Scholar
  62. 62.
    Rosiak JM (1994) Radiation formation of hydrogels for drug delivery. J Control Release 31(1):9–19CrossRefGoogle Scholar
  63. 63.
    Charlesby A (1960) Atomic radiation and polymers. Pregamon Press, OxfordGoogle Scholar
  64. 64.
    Charlesby A, Alexander P (1955) Reticulation of polymers in aqueous solution by γ-rays. J Chim Phys PCB 52:699–709CrossRefGoogle Scholar
  65. 65.
    Charlesby A, Alexander P (1957) Effect of X-rays and γ-rays on synthetic polymers in aqueous solution. J Polym Sci 23:355–375CrossRefGoogle Scholar
  66. 66.
    Sakurada I, Ikada Y (1996) Effects of Gamma Radiation on Polymer in Solution (IX): a turbidimetric study on solution of poly(vinyl alcohol) irradiated below critical concentration for gel-formation (Special Issue on Physical, Chemical and Biological Effects of Gamma Radiation, VII). Bull Inst Chem Res Kyoto Univ 44(1):66–73Google Scholar
  67. 67.
    Schnabel W, Borgwardt U (1969) Über die vernetzung von polyäthylenoxid in lösung unter der einwirkung von 60CO-γ-strahlen. Makromol Chem 123:73–79CrossRefGoogle Scholar
  68. 68.
    Ulanski P, Rosiak JM (1999) The use of radiation technique in the synthesis of polymeric nanogels. Nucl Instrum Methods Phys Res B 151(1–4):356–360CrossRefGoogle Scholar
  69. 69.
    Kadlubowski S (2014) Radiation-induced synthesis of nanogels based on poly(N-vinyl-2-pyrrolidone)—a review. Radiat Phys Chem 102:29–39 and references hereinGoogle Scholar
  70. 70.
    Ulanski P, Janik I, Rosiak JM (1998) Radiation formation of polymeric nanogels. Radiat Phys Chem 52:289–294CrossRefGoogle Scholar
  71. 71.
    Ulanski P, Kadlubowski S, Rosiak JM (2002) Synthesis of poly (acrylic acid) nanogels by preparative pulse radiolysis. Radiat Phys Chem 63(3–6):533–537CrossRefGoogle Scholar
  72. 72.
    Kadlubowski S, Grobelny J, Olejniczak W, Cichomski M, Ulanski P (2003) Pulses of fast electrons as a tool to synthesize poly (acrylic acid) nanogels. Intramolecular cross-linking of linear polymer chains in additive-free aqueous solution. Macromolecules 36(7):2484–2492CrossRefGoogle Scholar
  73. 73.
    Arndt K-F, Schmidt T, Reichelt R (2001) Thermo-sensitive poly(methyl vinyl ether) micro-gel formed by high energy radiation. Polymer 42:6785–6791CrossRefGoogle Scholar
  74. 74.
    Querner C, Schmidt T, Arndt K-F (2004) Characterization of structural changes of poly(vinyl methyl ether) gamma-irradiated in diluted aqueous solutions. Langmuir 20(7):2883–2889CrossRefGoogle Scholar
  75. 75.
    Schmidt T, Janik I, Kadlubowski S, Ulanski P, Rosiak JM, Reichelt R, Arndt K-F (2005) Pulsed electron beam irradiation of dilute aqueous poly (vinyl methyl ether) solutions. Polymer 46(23):9908–9918CrossRefGoogle Scholar
  76. 76.
    El-Rehim HAA (2005) Swelling of radiation crosslinked acrylamide-based microgels and their potential applications. Radiat Phys Chem 74(2):111–117CrossRefGoogle Scholar
  77. 77.
    Picos-Corrales LA, Licea-Claveríe A, Arndt K-F (2012) Stimuli-responsive nanogels by e-beam irradiation of dilute aqueous micellar solutions: Nanogels with pH controlled LCST. Chapter 7: Polymer Nanotechnology. In: Nanotechnology 2012: advanced materials, CNTs, particles, films and composites, vol 1. NSTI publicationGoogle Scholar
  78. 78.
    Chmielewski AG, Haji-Saeid M, Shamshad Ahmed S (2005) Progress in radiation processing of polymers. Nucl Instrum Methods Phys Res Sect B 236(1):44–54CrossRefGoogle Scholar
  79. 79.
    Sabatino MA, Bulone D, Veres M, Spinella A, Spadaro G, Dispenza C (2013) Structure of e-beam sculptured poly(N-vinylpyrrolidone) networks across different length-scales, from macro to nano. Polymer 54(1):54–64CrossRefGoogle Scholar
  80. 80.
    Dispenza C, Sabatino MA, Grimaldi N, Spadaro G, Bulone D, Bondì ML, Adamo G, Rigogliuso S (2012) Large-scale radiation manufacturing of hierarchically assembled nanogels. Chem Eng Trans 27:229C–234CGoogle Scholar
  81. 81.
    Dispenza C, Sabatino MA, Grimaldi N, Bulone D, Bondi ML, Casaletto MP, Rigogliuso S, Adamo G, Ghersi G (2012) Minimalism in radiation synthesis of biomedical functional nanogels. Biomacromolecules 13:1805–1817CrossRefGoogle Scholar
  82. 82.
    Adamo G, Grimaldi N, Sabatino MA, Walo M, Dispenza C, Ghersi G (2016) E-beam crosslinked nanogels conjugated with monoclonal antibodies in targeting strategies. Biol Chem. doi: 10.1515/hsz-2016-0255
  83. 83.
    Spinks JWT, Woods RJ (1990) An introduction to radiation chemistry. Wiley-Interscience, Wiley, New YorkGoogle Scholar
  84. 84.
    Alfassi ZB (1999) General aspects of the chemistry of radicals. Wiley, New YorkGoogle Scholar
  85. 85.
    Dispenza C, Sabatino M, Grimaldi N, Mangione M, Walo M, Murugan E, Jonsson M (2016) On the origin of functionalisation in one-pot radiation synthesis of nanogels from aqueous polymer solutions. RSC Adv 6(4):2582–2591CrossRefGoogle Scholar
  86. 86.
    Plonka A (1991) Developments in dispersive kinetics. Prog React Kinet 16:157–333Google Scholar
  87. 87.
    Jeszka JK, Kadlubowski S, Ulanski P (2006) Monte Carlo simulations of nanogels formation by intramolecular recombination of radicals on polymer chain. Dispersive kinetics controlled by chain dynamics. Macromolecules 39:857–870CrossRefGoogle Scholar
  88. 88.
    An JC, Weaver A, Kim B, Barkatt A, Poster D, Vreeland WN, Silverman J, Al-Sheikhly M (2011) Radiation-induced synthesis of poly(vinylpyrrolidone) nanogel. Polymer 52:5746–5755CrossRefGoogle Scholar
  89. 89.
    Schmitz KS, Wang B, Kokufuta E (2001) Mechanism of microgel formation via cross-linking of polymers in their dilute solutions: mathematical explanation with computer simulations. Macromolecules 34:8370–8377CrossRefGoogle Scholar
  90. 90.
    Brasch U, Burchard W (1996) Preparation and solution properties of microhydrogels from poly(vinyl alcohol). Macromol Chem Phys 197:223–235CrossRefGoogle Scholar
  91. 91.
    Kadlubowski S, Ulanski P, Rosiak JM (2012) Synthesis of tailored nanogels by means of two-stage irradiation. Polymer 53:1985–1991CrossRefGoogle Scholar
  92. 92.
    Gorlich W, Schnabel W (1973) Untersuchungen uber dei Eiflu der Ladungsdichte aur die gegenseitige Desaktvierung von Polyion-Mackroradikalen. Die Macromoleculare Chemie 164:225–235CrossRefGoogle Scholar
  93. 93.
    Grimaldi N, Sabatino MA, Przybytniak G, Kaluska I, Bondi’ ML, Bulone D, Alessi S, Spadaro G, Dispenza C (2014) High-energy radiation processing, a smart approach to obtain PVP-graft-AA nanogels. Radiat Phys Chem 94:76–79CrossRefGoogle Scholar
  94. 94.
    Henke A, Kadłubowski S, Ulański P, Arndt K-F, Rosiak JM (2005) Radiation-induced cross-linking of polyvinylpyrrolidone-poly(acrylic acid) complexes. Nucl Instr Meth Phys Res B 236:391–398CrossRefGoogle Scholar
  95. 95.
    El-Rehim HAA, Hegazy ESA, Hamed AA, Swilem AE (2013) Controlling the size and swellability of stimuli-responsive polyvinylpyrrolidone–poly (acrylic acid) nanogels synthesized by gamma radiation-induced template polymerization. Eur Polym J 49(3):601–612CrossRefGoogle Scholar
  96. 96.
    Adamo G, Grimaldi N, Campora S, Sabatino MA, Dispenza C, Ghersi G (2014) Glutathione-sensitive nanogels for drug release. Chem Eng Trans 38:457–462Google Scholar
  97. 97.
    Dispenza C, Adamo G, Sabatino MA, Grimaldi N, Bulone D, Bondì ML, Rigogliuso S, Ghersi G (2014) Oligonucleotides-decorated-poly(N-vinyl pyrrolidone) nanogels for gene delivery. J Appl Polym Sci 131(2):239774–239780CrossRefGoogle Scholar
  98. 98.
    El-Rehim HAA, Swilem AE, Klingner A, Hegazy ESA, Hamed AA (2013) Developing the potential ophthalmic applications of pilocarpine entrapped into polyvinylpyrrolidone-poly(acrylic acid) nanogel dispersions prepared by γ radiation 2013. Biomacromolecules 14(3):688–698CrossRefGoogle Scholar
  99. 99.
    Lorenzo A, Picos-Corrales LA, Angel Licea-Claveríe A, Arndt K-F (2014) React Funct Polym 75:31–40CrossRefGoogle Scholar
  100. 100.
    Meléndez-Orti HI, Peralta RD, Bucio E, Zerrweck-Maldonado L (2014) Preparation of stimuli-responsive nanogels of poly [2-(dimethylamino) ethyl methacrylate] by heterophase and microemulsion polymerization using gamma radiation Polym. Eng Sci 54:1625–1631Google Scholar
  101. 101.
    Yusof H, Naurah MI, Liyana MAN (2014) Polyethylene glycol diacrylate microgels from irradiated micelles. Adv Mater Res 1024:316–319CrossRefGoogle Scholar

Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  1. 1.Dipartimento di Ingegneria Chimica, Gestionale, Informatica, MeccanicaUniversità degli Studi di PalermoPalermoItaly
  2. 2.School of Chemical Science and EngineeringRoyal Institute of Technology (KTH)StockholmSweden

Personalised recommendations