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143. Liu X-M, L-d Q, Tian J, Laquer FC, Ciborowski P, Wang D (2010) Syntheses of click
PEG-dexamethasone conjugates for the treatment of rheumatoid arthritis. Biomacromolecules 11:2621–2628
144. Sarkar D, Lopina ST (2007) Oxidative and enzymatic degradations of l-tyrosine based
polyurethanes. Polym Degrad Stab 92:1994–2004
145. Fu H, Gao H, Wu G, Wang Y, Fan Y, Ma J (2011) Preparation and tunable temperature
sensitivity of biodegradable polyurethane nanoassemblies from diisocyanate and poly(ethylene glycol). Soft Matter 7:3546–3552
146. Sun X, Gao H, Wu G, Wang Y, Fan Y, Ma J (2011) Biodegradable and temperatureresponsive polyurethanes for adriamycin delivery. Int J Pharm 412:52–58
147. Lundberg P, Lee BF, van den Berg SA, Pressly ED, Lee A, Hawker CJ, Lynd NA (2012) Poly
[(ethylene oxide)-co-(methylene ethylene oxide)]: a hydrolytically degradable poly(ethylene
oxide) platform. ACS Macro Lett 1:1240–1243
148. Chan TH, Ong BS (1978) Chemistry of allene oxides. J Org Chem 43:2994–3001
149. Lo W-J, Wu Y-J, Lee Y-P (2002) Isomers of S 2 O: Infrared absorption spectra of cyclic S 2 O in
solid Ar. J Chem Phys 117:6655–6661
150. Lo W-J, Wu Y-J, Lee Y-P (2003) Ultraviolet absorption spectrum of cyclic S 2 O in solid Ar.
J Phys Chem A 107:6944–6947
151. Nagahara H, Kagawa K, Iwaisako T, Masamoto J (1995) Initiation mechanism of the
copolymerization of 1,3,5-trioxane and ethylene oxide. Ind Eng Chem Res 34:2515–2519
152. Nagahara H, Kagawa K, Hamanaka K, Yoshida K, Iwaisako T, Masamoto J (2000) Acetal
copolymer from the copolymerization of trioxane and ethylene oxide. Ind Eng Chem Res
39:2275–2280
153. Yamasaki N, Kanaori K, Masamoto J (2001) Analysis of ethylene oxide sequences of the
acetal copolymer from trioxane and ethylene oxide. J Polym Sci A Polym Chem
39:3239–3245
154. Shenoi RA, Narayanannair JK, Hamilton JL, Lai BFL, Horte S, Kainthan RK, Varghese JP,
Rajeev KG, Manoharan M, Kizhakkedathu JN (2012) Branched multifunctional polyether
polyketals: variation of ketal group structure enables unprecedented control over polymer
degradation in solution and within cells. J Am Chem Soc 134:14945–14957
155. Shenoi RA, Lai BFL, Imran ul-haq M, Brooks DE, Kizhakkedathu JN (2013) Biodegradable
polyglycerols with randomly distributed ketal groups as multi-functional drug delivery
systems. Biomaterials 34:6068–6081
156. Binauld S, Stenzel MH (2013) Acid-degradable polymers for drug delivery: a decade of
innovation. Chem Commun 49:2082–2102
157. Wike-Hooley JL, Haveman J, Reinhold HS (1984) The relevance of tumour pH to the
treatment of malignant disease. Radiother Oncol 2:343–366
158. Tannock IF, Rotin D (1989) Acid pH in tumors and its potential for therapeutic exploitation.
Cancer Res 49:4373–4384
159. Roldo M, Barbu E, Brown JF, Laight DW, Smart JD, Tsibouklis J (2007) Azo compounds in
colon-specific drug delivery. Expert Opin Drug Deliv 4:547–560
160. Yu C, Kohn J (1999) Tyrosine-PEG-derived poly(ether carbonate)s as new biomaterials:
Part I: synthesis and evaluation. Biomaterials 20:253–264
161. Yu C, Mielewczyk SS, Breslauer KJ, Kohn J (1999) Tyrosine-PEG-derived poly(ether
carbonate)s as new biomaterials: Part II: study of inverse temperature transitions.
Biomaterials 20:265–272
162. Lendlein A, Sisson A (eds) (2011) Handbook of biodegradable polymers: synthesis, characterization and applications. Wiley-VCH, Weinheim
190
C. Dingels and H. Frey
(ethylene glycol) by copper(I)-catalyzed huisgen 1,3-dipolar cycloaddition. Biomacromolecules 8:2653–2658
143. Liu X-M, L-d Q, Tian J, Laquer FC, Ciborowski P, Wang D (2010) Syntheses of click
PEG-dexamethasone conjugates for the treatment of rheumatoid arthritis. Biomacromolecules 11:2621–2628
144. Sarkar D, Lopina ST (2007) Oxidative and enzymatic degradations of l-tyrosine based
polyurethanes. Polym Degrad Stab 92:1994–2004
145. Fu H, Gao H, Wu G, Wang Y, Fan Y, Ma J (2011) Preparation and tunable temperature
sensitivity of biodegradable polyurethane nanoassemblies from diisocyanate and poly(ethylene glycol). Soft Matter 7:3546–3552
146. Sun X, Gao H, Wu G, Wang Y, Fan Y, Ma J (2011) Biodegradable and temperatureresponsive polyurethanes for adriamycin delivery. Int J Pharm 412:52–58
147. Lundberg P, Lee BF, van den Berg SA, Pressly ED, Lee A, Hawker CJ, Lynd NA (2012) Poly
[(ethylene oxide)-co-(methylene ethylene oxide)]: a hydrolytically degradable poly(ethylene
oxide) platform. ACS Macro Lett 1:1240–1243
148. Chan TH, Ong BS (1978) Chemistry of allene oxides. J Org Chem 43:2994–3001
149. Lo W-J, Wu Y-J, Lee Y-P (2002) Isomers of S 2 O: Infrared absorption spectra of cyclic S 2 O in
solid Ar. J Chem Phys 117:6655–6661
150. Lo W-J, Wu Y-J, Lee Y-P (2003) Ultraviolet absorption spectrum of cyclic S 2 O in solid Ar.
J Phys Chem A 107:6944–6947
151. Nagahara H, Kagawa K, Iwaisako T, Masamoto J (1995) Initiation mechanism of the
copolymerization of 1,3,5-trioxane and ethylene oxide. Ind Eng Chem Res 34:2515–2519
152. Nagahara H, Kagawa K, Hamanaka K, Yoshida K, Iwaisako T, Masamoto J (2000) Acetal
copolymer from the copolymerization of trioxane and ethylene oxide. Ind Eng Chem Res
39:2275–2280
153. Yamasaki N, Kanaori K, Masamoto J (2001) Analysis of ethylene oxide sequences of the
acetal copolymer from trioxane and ethylene oxide. J Polym Sci A Polym Chem
39:3239–3245
154. Shenoi RA, Narayanannair JK, Hamilton JL, Lai BFL, Horte S, Kainthan RK, Varghese JP,
Rajeev KG, Manoharan M, Kizhakkedathu JN (2012) Branched multifunctional polyether
polyketals: variation of ketal group structure enables unprecedented control over polymer
degradation in solution and within cells. J Am Chem Soc 134:14945–14957
155. Shenoi RA, Lai BFL, Imran ul-haq M, Brooks DE, Kizhakkedathu JN (2013) Biodegradable
polyglycerols with randomly distributed ketal groups as multi-functional drug delivery
systems. Biomaterials 34:6068–6081
156. Binauld S, Stenzel MH (2013) Acid-degradable polymers for drug delivery: a decade of
innovation. Chem Commun 49:2082–2102
157. Wike-Hooley JL, Haveman J, Reinhold HS (1984) The relevance of tumour pH to the
treatment of malignant disease. Radiother Oncol 2:343–366
158. Tannock IF, Rotin D (1989) Acid pH in tumors and its potential for therapeutic exploitation.
Cancer Res 49:4373–4384
159. Roldo M, Barbu E, Brown JF, Laight DW, Smart JD, Tsibouklis J (2007) Azo compounds in
colon-specific drug delivery. Expert Opin Drug Deliv 4:547–560
160. Yu C, Kohn J (1999) Tyrosine-PEG-derived poly(ether carbonate)s as new biomaterials:
Part I: synthesis and evaluation. Biomaterials 20:253–264
161. Yu C, Mielewczyk SS, Breslauer KJ, Kohn J (1999) Tyrosine-PEG-derived poly(ether
carbonate)s as new biomaterials: Part II: study of inverse temperature transitions.
Biomaterials 20:265–272
162. Lendlein A, Sisson A (eds) (2011) Handbook of biodegradable polymers: synthesis, characterization and applications. Wiley-VCH, Weinheim
190
C. Dingels and H. Frey