메뉴 건너뛰기




Volumn 70, Issue 10, 2013, Pages 2675-2689

Preparation and properties of a dually responsive hydrogels based on polyampholyte for oral delivery of drugs

Author keywords

Casein; Drug release systems; Graft copolymer; Hydrogels; Poly(N isopropylacrylamide); Stimuli sensitive polymers

Indexed keywords

DRUG RELEASE SYSTEM; PH-SENSITIVE HYDROGEL; POLY (N ISOPROPYLACRYLAMIDE); RESPONSIVE HYDROGELS; SENSITIVITY TO TEMPERATURES; STIMULI-SENSITIVE POLYMERS; TEMPERATURE SENSITIVE; TEMPERATURE-SENSITIVE HYDROGELS;

EID: 84883460031     PISSN: 01700839     EISSN: None     Source Type: Journal    
DOI: 10.1007/s00289-013-0975-3     Document Type: Article
Times cited : (9)

References (37)
  • 1
    • 13544275935 scopus 로고    scopus 로고
    • Novel hydrogels with excellent mechanical performance
    • 10.1016/j.progpolymsci.2004.11.003 1:CAS:528:DC%2BD2MXhtlOhtrk%3D
    • Tanaka Y, Gong JP, Osada Y (2005) Novel hydrogels with excellent mechanical performance. Prog Polym Sci 30:1-9
    • (2005) Prog Polym Sci , vol.30 , pp. 1-9
    • Tanaka, Y.1    Gong, J.P.2    Osada, Y.3
  • 2
    • 78650920377 scopus 로고    scopus 로고
    • Cellular compatibility of copolymer hydrogels based on site-selectively-modified chitosan with poly(N-isopropyl acrylamide)
    • 10.1002/app.32806 1:CAS:528:DC%2BC3MXhtVersQ%3D%3D
    • Don TM, Chou SC, Cheng LP, Tai HY (2011) Cellular compatibility of copolymer hydrogels based on site-selectively-modified chitosan with poly(N-isopropyl acrylamide). J Appl Polym Sci 120:1-12
    • (2011) J Appl Polym Sci , vol.120 , pp. 1-12
    • Don, T.M.1    Chou, S.C.2    Cheng, L.P.3    Tai, H.Y.4
  • 3
    • 70349249451 scopus 로고    scopus 로고
    • Dielectric properties of thermo-reversible hydrogels: The case of a dextran copolymer grafted with poly(N-isopropylacrylamide)
    • 10.1021/jp9032468 1:CAS:528:DC%2BD1MXptVKnu74%3D
    • Masci G, Cametti C (2009) Dielectric properties of thermo-reversible hydrogels: the case of a dextran copolymer grafted with poly(N- isopropylacrylamide). J Phys Chem B 113:11421-11428
    • (2009) J Phys Chem B , vol.113 , pp. 11421-11428
    • Masci, G.1    Cametti, C.2
  • 4
    • 36349037114 scopus 로고    scopus 로고
    • Temperature-responsive polymers with LCST in the physiological range and their applications in textiles
    • 10.1002/pi.2277 1:CAS:528:DC%2BD2sXhtlKktLjN
    • Crespy D, Rossi R (2007) Temperature-responsive polymers with LCST in the physiological range and their applications in textiles. Polym Int 56:1461-1468
    • (2007) Polym Int , vol.56 , pp. 1461-1468
    • Crespy, D.1    Rossi, R.2
  • 5
    • 0041767561 scopus 로고    scopus 로고
    • Water-soluble temperature-responsive poly(vinyl alcoho-co-vinyl acetal)s
    • 10.1007/s00289-003-0178-4
    • Chritova D, Ivanova S, Ivanova G (2003) Water-soluble temperature-responsive poly(vinyl alcoho-co-vinyl acetal)s. Polym Bull 50:367-372
    • (2003) Polym Bull , vol.50 , pp. 367-372
    • Chritova, D.1    Ivanova, S.2    Ivanova, G.3
  • 6
    • 42149109609 scopus 로고    scopus 로고
    • Study of pH-responsive microgels containing methacrylic acid: Effects of particle composition and added calcium
    • 10.1021/la703597a 1:CAS:528:DC%2BD1cXit1Gqu78%3D
    • Dalmont H, Pinprayoon O, Saunders BR (2008) Study of pH-responsive microgels containing methacrylic acid: effects of particle composition and added calcium. Langmuir 24:2834-2840
    • (2008) Langmuir , vol.24 , pp. 2834-2840
    • Dalmont, H.1    Pinprayoon, O.2    Saunders, B.R.3
  • 7
    • 33644781655 scopus 로고    scopus 로고
    • Synthesis and characterization of pH-responsive hydrogels based on chemically modified Arabic gum polysaccharide
    • 10.1016/j.polymer.2006.01.058 1:CAS:528:DC%2BD28Xitlejtb8%3D
    • Reis AV, Guilherme MR, Cavalcanti OA, Rubira AF, Muniz EC (2006) Synthesis and characterization of pH-responsive hydrogels based on chemically modified Arabic gum polysaccharide. Polymer 47:2023-2029
    • (2006) Polymer , vol.47 , pp. 2023-2029
    • Reis, A.V.1    Guilherme, M.R.2    Cavalcanti, O.A.3    Rubira, A.F.4    Muniz, E.C.5
  • 8
    • 79951682126 scopus 로고    scopus 로고
    • PH responsive itaconic acid grafted alginate microspheres for the controlled release of nifedipine
    • 10.1016/j.carbpol.2010.12.054 1:CAS:528:DC%2BC3MXitVShtbg%3D
    • Isiklan N, Inal Kursun MF, Ercan G (2011) pH responsive itaconic acid grafted alginate microspheres for the controlled release of nifedipine. Carbohyd Polym 84:933-943
    • (2011) Carbohyd Polym , vol.84 , pp. 933-943
    • Isiklan, N.1    Inal Kursun, M.F.2    Ercan, G.3
  • 9
    • 23744472584 scopus 로고    scopus 로고
    • PH switching on-off semi-IPN hydrogel based on cross-linked poly(acrylamide-co-acrylic acid) and linear polyallyamine
    • 10.1016/j.polymer.2005.05.121 1:CAS:528:DC%2BD2MXns1Smt7g%3D
    • Zhang YX, Wu FP, Li MZ, Wang EJ (2005) pH switching on-off semi-IPN hydrogel based on cross-linked poly(acrylamide-co-acrylic acid) and linear polyallyamine. Polymer 46:7695-7700
    • (2005) Polymer , vol.46 , pp. 7695-7700
    • Zhang, Y.X.1    Wu, F.P.2    Li, M.Z.3    Wang, E.J.4
  • 10
    • 78650600628 scopus 로고    scopus 로고
    • Light-responsive polymer micelles, nano- and microgels based on the reversible photodimerization of coumarin
    • 10.1016/j.dyepig.2010.03.032 1:CAS:528:DC%2BC3cXhs1SrtbzE
    • He J, Zhao Y (2011) Light-responsive polymer micelles, nano- and microgels based on the reversible photodimerization of coumarin. Dyes Pigments 89:278-283
    • (2011) Dyes Pigments , vol.89 , pp. 278-283
    • He, J.1    Zhao, Y.2
  • 11
    • 55849090299 scopus 로고    scopus 로고
    • Responsive polymers in controlled drug delivery
    • 10.1016/j.progpolymsci.2008.07.005 1:CAS:528:DC%2BD1cXhtlyqtbvE
    • Bajpai AK, Shukla SK, Bhanu S, Kankane S (2008) Responsive polymers in controlled drug delivery. Prog Polym Sci 33:1088-1118
    • (2008) Prog Polym Sci , vol.33 , pp. 1088-1118
    • Bajpai, A.K.1    Shukla, S.K.2    Bhanu, S.3    Kankane, S.4
  • 12
    • 16344383659 scopus 로고    scopus 로고
    • Chymotrypsin responsive hydrogels: Application of a disulfide exchange protocol for the reparation of methacrylamide containing peptides
    • 10.1021/bm049349v 1:CAS:528:DC%2BD2MXhvVarug%3D%3D
    • Plunkett KN, Berkowski K, Moore JS (2005) Chymotrypsin responsive hydrogels: application of a disulfide exchange protocol for the reparation of methacrylamide containing peptides. Biomacromolecules 6:632-637
    • (2005) Biomacromolecules , vol.6 , pp. 632-637
    • Plunkett, K.N.1    Berkowski, K.2    Moore, J.S.3
  • 13
    • 16344387352 scopus 로고    scopus 로고
    • PEG-grafted chitosan as an injectable thermosensitive hydrogel for sustained protein release
    • 10.1016/j.jconrel.2004.12.019 1:CAS:528:DC%2BD2MXjt1aht7g%3D
    • Bhattarai N, Ramay HR, Gunn J, Matsen FA, Zhang M (2005) PEG-grafted chitosan as an injectable thermosensitive hydrogel for sustained protein release. J Control Release 103:609-624
    • (2005) J Control Release , vol.103 , pp. 609-624
    • Bhattarai, N.1    Ramay, H.R.2    Gunn, J.3    Matsen, F.A.4    Zhang, M.5
  • 14
    • 15944417455 scopus 로고    scopus 로고
    • Stimuli responsive polymers for biomedical applications
    • 10.1039/b406727d 1:CAS:528:DC%2BD2MXhs1agu74%3D
    • Alarcon CDL, Penndam S, Alexander C (2005) Stimuli responsive polymers for biomedical applications. Chem Soc Rev 34:276-285
    • (2005) Chem Soc Rev , vol.34 , pp. 276-285
    • Alarcon, C.D.L.1    Penndam, S.2    Alexander, C.3
  • 15
    • 7544242668 scopus 로고    scopus 로고
    • A new double-responsive block copolymer synthesized via raft polymerization: Poly(N-isopropylacrylamide)-b-poly(acrylic acid)
    • 10.1021/ma035838w 1:CAS:528:DC%2BD2cXns12qs78%3D
    • Schilli CM, Zhang M, Rizzardo E, Thang SH, Chong YK, Edwards K (2004) A new double-responsive block copolymer synthesized via raft polymerization: poly(N-isopropylacrylamide)-b-poly(acrylic acid). Macromolecules 37:7861-7866
    • (2004) Macromolecules , vol.37 , pp. 7861-7866
    • Schilli, C.M.1    Zhang, M.2    Rizzardo, E.3    Thang, S.H.4    Chong, Y.K.5    Edwards, K.6
  • 16
    • 28844448256 scopus 로고    scopus 로고
    • Novel functional biodegradable polymer IV: PH-sensitive controlled release of fibroblast growth factor-2 from a poly(gamma-glutamic acid)-sulfonate matrix for tissue engineering
    • 10.1021/bm050369m 1:CAS:528:DC%2BD2MXhtFWhu7vO
    • Matsusaki M, Akashi M (2005) Novel functional biodegradable polymer IV: pH-sensitive controlled release of fibroblast growth factor-2 from a poly(gamma-glutamic acid)-sulfonate matrix for tissue engineering. Biomacromolecules 6:3351-3356
    • (2005) Biomacromolecules , vol.6 , pp. 3351-3356
    • Matsusaki, M.1    Akashi, M.2
  • 17
    • 19444376142 scopus 로고    scopus 로고
    • Preparation and characterization of intelligent core-shell nanoparticles based on poly(D, L-lactide)-g-poly(N-isopropyl acrylamide-co-methacrylic acid)
    • 10.1016/j.jconrel.2005.03.004 1:CAS:528:DC%2BD2MXksVyjtbg%3D
    • Lo CL, Lin KM, Hsiue GH (2005) Preparation and characterization of intelligent core-shell nanoparticles based on poly(D, L-lactide)-g-poly(N- isopropyl acrylamide-co-methacrylic acid). J Control Release 104:477-488
    • (2005) J Control Release , vol.104 , pp. 477-488
    • Lo, C.L.1    Lin, K.M.2    Hsiue, G.H.3
  • 18
    • 0343338265 scopus 로고    scopus 로고
    • PH/temperature-responsive behaviors of semi-IPN and comb-type graft hydrogels composed of alginate and poly (N-isopropylacrylamide)
    • 10.1016/S0032-3861(01)00143-4 1:CAS:528:DC%2BD3MXjt12gtbo%3D
    • Ju HK, Kim SY, Lee YM (2001) pH/temperature-responsive behaviors of semi-IPN and comb-type graft hydrogels composed of alginate and poly (N-isopropylacrylamide). Polymer 42:6851-6857
    • (2001) Polymer , vol.42 , pp. 6851-6857
    • Ju, H.K.1    Kim, S.Y.2    Lee, Y.M.3
  • 19
    • 0036154023 scopus 로고    scopus 로고
    • Synthesis and characterization of pH/temperature sensitive hydrogels based on chitosan derivative
    • 10.1007/s002890200008 1:CAS:528:DC%2BD38XhtlKgsr8%3D
    • Shin MS, Kang HS, Park TG, Yang JW (2002) Synthesis and characterization of pH/temperature sensitive hydrogels based on chitosan derivative. Polym Bull 47:451-456
    • (2002) Polym Bull , vol.47 , pp. 451-456
    • Shin, M.S.1    Kang, H.S.2    Park, T.G.3    Yang, J.W.4
  • 20
    • 34247573414 scopus 로고    scopus 로고
    • Functional copolymers of N-isopropylacrylamide for bioengineering applications
    • 10.1016/j.progpolymsci.2007.01.006 1:CAS:528:DC%2BD2sXkvFyrt7o%3D
    • Rzaev ZMO, Dincer S, Piskin E (2007) Functional copolymers of N-isopropylacrylamide for bioengineering applications. Prog Polym Sci 32:534-595
    • (2007) Prog Polym Sci , vol.32 , pp. 534-595
    • Rzaev, Z.M.O.1    Dincer, S.2    Piskin, E.3
  • 21
    • 46049093569 scopus 로고    scopus 로고
    • PH-dependent structures and properties of casein micelles
    • 10.1016/j.bpc.2008.03.012 1:CAS:528:DC%2BD1cXotlOitrw%3D
    • Liu Y, Guo R (2008) pH-dependent structures and properties of casein micelles. Biophys Chem 136:67-73
    • (2008) Biophys Chem , vol.136 , pp. 67-73
    • Liu, Y.1    Guo, R.2
  • 22
    • 77957346768 scopus 로고    scopus 로고
    • Beta-casein nanoparticles as an oral delivery system for chemotherapeutic drugs: Impact of drug structure and properties on co-assembly
    • 10.1007/s11095-010-0222-7 1:CAS:528:DC%2BC3cXhtVSmu7zO
    • Shapira A, Assaraf YG, Epstein D, Livney YD (2010) Beta-casein nanoparticles as an oral delivery system for chemotherapeutic drugs: impact of drug structure and properties on co-assembly. Pharm Res 27:2175-2186
    • (2010) Pharm Res , vol.27 , pp. 2175-2186
    • Shapira, A.1    Assaraf, Y.G.2    Epstein, D.3    Livney, Y.D.4
  • 23
    • 0028130012 scopus 로고
    • Casein microbeads as a controlled parenteral drug-delivery system
    • 10.3109/03639049409042664 1:CAS:528:DyaK2cXlvVOjtbo%3D
    • Bayomi MA, Elsayed YM (1994) Casein microbeads as a controlled parenteral drug-delivery system. Drug Dev Ind Pharm 20:2607-2617
    • (1994) Drug Dev Ind Pharm , vol.20 , pp. 2607-2617
    • Bayomi, M.A.1    Elsayed, Y.M.2
  • 24
    • 77955276587 scopus 로고    scopus 로고
    • Beta-casein-based nanovehicles for oral delivery of chemotherapeutic drugs: Drug-protein interactions and mitoxantrone loading capacity
    • 10.1016/j.nano.2010.01.003 1:CAS:528:DC%2BC3cXhtVyrsrfK
    • Shapira A, Markman G, Assaraf YG, Livney YD (2010) Beta-casein-based nanovehicles for oral delivery of chemotherapeutic drugs: drug-protein interactions and mitoxantrone loading capacity. Nanomed Nanotechnol 6:547-555
    • (2010) Nanomed Nanotechnol , vol.6 , pp. 547-555
    • Shapira, A.1    Markman, G.2    Assaraf, Y.G.3    Livney, Y.D.4
  • 25
    • 77952953073 scopus 로고    scopus 로고
    • Novel casein hydrogels: Formation, structure and controlled drug release
    • 10.1016/j.colsurfb.2010.03.045 1:CAS:528:DC%2BC3cXmsVOnsr0%3D
    • Song F, Zhang LM, Shi JF, Li NN (2010) Novel casein hydrogels: formation, structure and controlled drug release. Colloids Surf B 79:142-148
    • (2010) Colloids Surf B , vol.79 , pp. 142-148
    • Song, F.1    Zhang, L.M.2    Shi, J.F.3    Li, N.N.4
  • 26
    • 34250000513 scopus 로고    scopus 로고
    • PH-induced structural transitions of caseins
    • 10.1016/j.jphotobiol.2007.04.004 1:CAS:528:DC%2BD2sXmsFKlsbg%3D
    • Chakraborty A, Basak S (2007) pH-induced structural transitions of caseins. J Photochem Photobiol B 87:191-199
    • (2007) J Photochem Photobiol B , vol.87 , pp. 191-199
    • Chakraborty, A.1    Basak, S.2
  • 27
    • 84862815650 scopus 로고    scopus 로고
    • Synthesis and characterization of dual responsive graft copolymers composed of casein and poly(N-isopropylacrylamide)
    • 10.1007/s10965-011-9743-y
    • Cao ZF, Jin Y, Zhang BA, Miao Q, Ma CY (2012) Synthesis and characterization of dual responsive graft copolymers composed of casein and poly(N-isopropylacrylamide). J Polym Res 19:9743-9752
    • (2012) J Polym Res , vol.19 , pp. 9743-9752
    • Cao, Z.F.1    Jin, Y.2    Zhang, B.A.3    Miao, Q.4    Ma, C.Y.5
  • 28
    • 47549099798 scopus 로고    scopus 로고
    • Self-assembly of thermo- and pH-responsive poly(acrylic acid)-b-poly(N-isopropylacrylamide) micelles for drug delivery
    • 10.1002/pola.22831 1:CAS:528:DC%2BD1cXpt12ltrg%3D
    • Li GY, Song S, Guo L, Ma SM (2008) Self-assembly of thermo- and pH-responsive poly(acrylic acid)-b-poly(N-isopropylacrylamide) micelles for drug delivery. J Polym Sci A Polym Chem 46:5028-5035
    • (2008) J Polym Sci A Polym Chem , vol.46 , pp. 5028-5035
    • Li, G.Y.1    Song, S.2    Guo, L.3    Ma, S.M.4
  • 29
    • 45449090078 scopus 로고    scopus 로고
    • Novel temperature- and pH-responsive graft copolymers composed of poly(l-glutamic acid) and poly(N-isopropylacrylamide)
    • 10.1002/pola.22760 1:CAS:528:DC%2BD1cXnt1Chsrw%3D
    • He CL, Zhao CW, Guo XH (2008) Novel temperature- and pH-responsive graft copolymers composed of poly(l-glutamic acid) and poly(N-isopropylacrylamide). J Polym Sci A Polym Chem 46:4140-4150
    • (2008) J Polym Sci A Polym Chem , vol.46 , pp. 4140-4150
    • He, C.L.1    Zhao, C.W.2    Guo, X.H.3
  • 30
    • 77955316335 scopus 로고    scopus 로고
    • Recombinant human serum albumin hydrogel as a novel drug delivery vehicle
    • 10.1016/j.msec.2010.02.020 1:CAS:528:DC%2BC3cXlvFWkt7g%3D
    • Hirose M, Tachibana A, Tanabe T (2010) Recombinant human serum albumin hydrogel as a novel drug delivery vehicle. Mater Sci Eng C 30:664-669
    • (2010) Mater Sci Eng C , vol.30 , pp. 664-669
    • Hirose, M.1    Tachibana, A.2    Tanabe, T.3
  • 31
    • 0037195303 scopus 로고    scopus 로고
    • New Route to Amphiphilic Core-Shell Polymer Nanospheres: Graft Copolymerization of Methyl Methacrylate from Water-Soluble Polymer Chains Containing Amino Groups
    • 10.1021/la0261343
    • Li P, Zhu JM, Sunintaboon P, Harris FW (2002) New Route to Amphiphilic Core-Shell Polymer Nanospheres: graft Copolymerization of Methyl Methacrylate from Water-Soluble Polymer Chains Containing Amino Groups. Langmuir 18:8641-8646
    • (2002) Langmuir , vol.18 , pp. 8641-8646
    • Li, P.1    Zhu, J.M.2    Sunintaboon, P.3    Harris, F.W.4
  • 32
    • 79952010071 scopus 로고    scopus 로고
    • Sonochemical synthesis and characterisation of thermoresponsive microgel particles
    • 10.1016/j.colsurfa.2011.01.015 1:CAS:528:DC%2BC3MXisVKqt70%3D
    • Widnersson I, Teo BM (2011) Sonochemical synthesis and characterisation of thermoresponsive microgel particles. Colloids Surf A 377:342-348
    • (2011) Colloids Surf A , vol.377 , pp. 342-348
    • Widnersson, I.1    Teo, B.M.2
  • 33
    • 34548215638 scopus 로고    scopus 로고
    • Synthesis, characterization, and influence of synthesis parameters on particle sizes of a new microgel family
    • 10.1002/pola.22133
    • Virginia SM, Leyre P, Estibaliz H, Teresa H, Issa K (2007) Synthesis, characterization, and influence of synthesis parameters on particle sizes of a new microgel family. J Polym Sci A Polym Chem 45:3833-3842
    • (2007) J Polym Sci A Polym Chem , vol.45 , pp. 3833-3842
    • Virginia, S.M.1    Leyre, P.2    Estibaliz, H.3    Teresa, H.4    Issa, K.5
  • 34
    • 0036603966 scopus 로고    scopus 로고
    • Preparation of poly(N-ethyl methacrylamide) particles via an emulsion/precipitation process: The role of the crosslinker
    • 10.1002/pola.10259 1:CAS:528:DC%2BD38XjvVKnsr0%3D
    • Hazot P, Chapel JP, Pichot C, Elaissari A, Delair T (2002) Preparation of poly(N-ethyl methacrylamide) particles via an emulsion/precipitation process: the role of the crosslinker. J Polym Sci A Polym Chem 40:1808-1817
    • (2002) J Polym Sci A Polym Chem , vol.40 , pp. 1808-1817
    • Hazot, P.1    Chapel, J.P.2    Pichot, C.3    Elaissari, A.4    Delair, T.5
  • 35
    • 79955539042 scopus 로고    scopus 로고
    • PH- and temperature-sensitive chitosan hydrogels: Swelling and MRI Studies
    • 10.1002/macp.201000301 1:CAS:528:DC%2BC3MXlt1GnsLk%3D
    • Goycoolea FM, Fernandez-Valle ME, Aranaz I, Heras A (2011) pH- and temperature-sensitive chitosan hydrogels: swelling and MRI Studies. Macromol Chem Phys 212:887-895
    • (2011) Macromol Chem Phys , vol.212 , pp. 887-895
    • Goycoolea, F.M.1    Fernandez-Valle, M.E.2    Aranaz, I.3    Heras, A.4
  • 36
    • 24344507763 scopus 로고    scopus 로고
    • Preparation, characterization, swelling and in vitro drug release behaviour of poly[N-acryloylglycine-chitosan] interpolymeric pH and thermally-responsive hydrogels
    • 10.1016/j.eurpolymj.2005.05.035 1:CAS:528:DC%2BD2MXpvVWnu7k%3D
    • El-Sherbiny IM, Lins RJ, Abdel-Bary EM, Harding DRK (2005) Preparation, characterization, swelling and in vitro drug release behaviour of poly[N-acryloylglycine-chitosan] interpolymeric pH and thermally-responsive hydrogels. Eur Polym J 41:2584-2591
    • (2005) Eur Polym J , vol.41 , pp. 2584-2591
    • El-Sherbiny, I.M.1    Lins, R.J.2    Abdel-Bary, E.M.3    Harding, D.R.K.4
  • 37
    • 34948888183 scopus 로고    scopus 로고
    • Preparation and properties of a pH/temperature-responsive carboxymethyl chitosan/poly(N-isopropylacrylamide) semi-IPN hydrogel for oral delivery of drugs
    • 10.1016/j.carres.2007.07.007 1:CAS:528:DC%2BD2sXhtVOlsb3M
    • Guo BL, Gao QY (2007) Preparation and properties of a pH/temperature-responsive carboxymethyl chitosan/poly(N-isopropylacrylamide) semi-IPN hydrogel for oral delivery of drugs. Carbohydr Res 342:2416-2422
    • (2007) Carbohydr Res , vol.342 , pp. 2416-2422
    • Guo, B.L.1    Gao, Q.Y.2


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.