title: Sustained release of risperidone from biodegradable microspheres prepared by in-situ suspension-evaporation process.
abstract: Risperidone-loaded poly (D,L-lactide-co-glycolide) (PLGA) microspheres were prepared with a suspension-evaporation process with an aqueous suspension containing an in situ-formed aluminum hydroxide inorganic gel (SEP-AL process) and evaluated for encapsulation efficiency, particle size, surface morphology, glass transition temperature, in vitro drug release profile, and in vivo behavior. The SEP-AL microspheres were compared with conventional oil-in-water (O/W) emulsion solvent evaporation method using polyvinylalcohol (PVA) as an emulsifier (CP-PVA process). The microspheres were spherical in shape. DSC measurements showed that risperidone crystallinity was greatly reduced due to the homogeneous distribution of risperidone in PLGA microspheres. In vitro drug release profile from the microspheres showed a sigmoidal pattern of negligible initial burst up to 24h and minimal release (time-lag) for 7 days. After the lag phase, slow release took a place up to 25 days and then rapid release occurred sharply for 1 week. In vivo rat pharmacokinetic profile from the microspheres showed very low blood concentration level at the initial phase (up to 24h) followed by the latent phase up to 21 days. At the 3rd week, main phase started and the blood concentration of the drug increased up to the 5th week, and then gradually decreased. The risperidone-loaded PLGA microspheres produced by SEP-AL process showed excellent controlled release characteristics for the effective treatment of schizophrenia patients.
authors.affiliation: College of Pharmacy, Yonsei University, 85 Songdogwahak-ro, Yeonsu-gu, Incheon 21983, Republic of Korea; Global Research Institute, BC World Pharm., Co., Ltd., Korea Bio Park A-3, 700 Daewangpangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi-do 13488, Republic of Korea.
authors.forename: Taekun
authors.initials: T
authors.lastname: An
authors.affiliation: Global Research Institute, BC World Pharm., Co., Ltd., Korea Bio Park A-3, 700 Daewangpangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi-do 13488, Republic of Korea.
authors.forename: Juhyuen
authors.initials: J
authors.lastname: Choi
authors.affiliation: Global Research Institute, BC World Pharm., Co., Ltd., Korea Bio Park A-3, 700 Daewangpangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi-do 13488, Republic of Korea.
authors.forename: Aram
authors.initials: A
authors.lastname: Kim
authors.affiliation: Global Research Institute, BC World Pharm., Co., Ltd., Korea Bio Park A-3, 700 Daewangpangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi-do 13488, Republic of Korea.
authors.forename: Jin Ho
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Global Research Institute, BC World Pharm., Co., Ltd., Korea Bio Park A-3, 700 Daewangpangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi-do 13488, Republic of Korea.
authors.forename: Yoonjin
authors.initials: Y
authors.lastname: Nam
authors.affiliation: Yonsei Institute of Pharmaceutical Sciences, Yonsei University, 85 Songdogwahak-ro, Yeonsu-gu, Incheon 21983, Republic of Korea.
authors.forename: Junsung
authors.initials: J
authors.lastname: Park
authors.affiliation: College of Pharmacy, Yonsei University, 85 Songdogwahak-ro, Yeonsu-gu, Incheon 21983, Republic of Korea.
authors.forename: Bo kyung
authors.initials: Bk
authors.lastname: Sun
authors.affiliation: Global Research Institute, BC World Pharm., Co., Ltd., Korea Bio Park A-3, 700 Daewangpangyo-ro, Bundang-gu, Seongnam-si, Gyeonggi-do 13488, Republic of Korea.
authors.forename: Hearan
authors.initials: H
authors.lastname: Suh
authors.affiliation: Esaias Research LLC, 29300 Henderson Ln, Highland, CA 92346, USA.
authors.forename: Cherng-ju
authors.initials: CJ
authors.lastname: Kim
authors.affiliation: College of Pharmacy, Yonsei University, 85 Songdogwahak-ro, Yeonsu-gu, Incheon 21983, Republic of Korea; Yonsei Institute of Pharmaceutical Sciences, Yonsei University, 85 Songdogwahak-ro, Yeonsu-gu, Incheon 21983, Republic of Korea. Electronic address: sjh11@yonsei.ac.kr.
authors.forename: Sung-Joo
authors.initials: SJ
authors.lastname: Hwang
mesh_terms: D000818:Animals; D014150:Antipsychotic Agents / Q000008:administration & dosage / Q000097:blood / Q000737:chemistry / Q000493:pharmacokinetics; D003692:Delayed-Action Preparations / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics; D018492:Dopamine Antagonists / Q000008:administration & dosage / Q000097:blood / Q000737:chemistry / Q000493:pharmacokinetics; D004339:Drug Compounding; D065546:Drug Liberation; D019344:Lactic Acid / Q000737:chemistry; D008297:Male; D008863:Microspheres; D010316:Particle Size; D011100:Polyglycolic Acid / Q000737:chemistry; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D017207:Rats, Sprague-Dawley; D018967:Risperidone / Q000008:administration & dosage* / Q000097:blood / Q000737:chemistry / Q000493:pharmacokinetics; D012702:Serotonin Antagonists / Q000008:administration & dosage / Q000097:blood / Q000737:chemistry / Q000493:pharmacokinetics
chemical_list: D014150:Antipsychotic Agents; D003692:Delayed-Action Preparations; D018492:Dopamine Antagonists; D012702:Serotonin Antagonists; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D018967:Risperidone
keywords: Aluminum hydroxide; Initial burst; Microspheres; PLGA; Risperidone