Injectable thermoresponsive hydrogel for prolonged therapeutic activity of donepezil-loaded microsphere
- 주제(키워드) microsphere , thermoresponsive hydrogel , donepezil , drug delivery system , sustained releasse
- 주제(DDC) 547
- 발행기관 아주대학교
- 지도교수 김문석
- 발행년도 2023
- 학위수여년월 2023. 8
- 학위명 박사
- 학과 및 전공 일반대학원 분자과학기술학과
- 실제URI http://www.dcollection.net/handler/ajou/000000032917
- 본문언어 영어
- 저작권 아주대학교 논문은 저작권에 의해 보호받습니다.
초록/요약
Donepezil (Do) is applied as an oral formulation for patients with Alzheimer's disease. However, it has the disadvantage of requiring daily administration along with the possibility of side effects. Recently, donepezil-loaded PLGA or PLA microspheres (Do-PLGA-M or Do-PLA-M) have been manufactured and studied for sustained-release drug delivery. However, the drug release of Do-PLGA-M or Do-PLA-M usually ends within 4 weeks due to the initial burst, which is a disadvantage of microspheres. In this study, Do-PLA-M was prepared as a combination formulation (Do-PLA-M/PCL) mixed with methoxy poly(ethylene glycol)-b-poly(ε-caprolactone) hydrogel (PCL) hydrogel, and the initial burst of microspheres was suppressed, and the drug release period was extended. Do-PLGA-M and Do-PLA-M prepared using a monoaxial-nozzle ultrasonic atomizer were produced with a high encapsulation rate and yield of about 93% and uniform particle size. Do-PLA-M/PCL was easily prepared because the successfully synthesized PCL and Do-PLA-M were mixed uniformly at room temperature. When evaluating the injectability and temperature sensitivity of Do-PLA-M/PCL, it was possible to inject easily and uniformly into the body without clogging. In addition, it was confirmed that it can be injected into a patient non-invasively as an appropriate injectable formulation through well-formed hydrogel. As a result, it was confirmed that the drug release behavior could be changed by the difference in the physical properties and biodegradation rate of the microspheres according to the characteristics of the matrix polymer. Do-PLA-M/PCL effectively suppressed the initial burst and delayed the biodegradation of Do-PLA-M as the PCL hydrogel served as a barrier covering Do-PLA-M. As a result, the drug release period of Do-PLA-M/PCL was stably extended for about 8 weeks. To compare the biodegradation rates of Do-PLGA-M, Do-PLA-M, and Do-PLA-M/PCL, micro-CT, SEM, NMR, and GPC were performed. As a result, the drug release period of Do-PLA-M/PCL was stably extended for about 8 weeks. To compare the biodegradation rates of Do-PLGA-M, Do-PLA-M, and Do-PLA-M/PCL, micro-CT, SEM, NMR, and GPC were performed. Do-PLGA-M showed the fastest biodegradation rate and Do-PLA-M/PCL showed the slowest. These results were consistent with the trend of drug release rate. When biocompatibility and inflammatory expression were evaluated, Do-PLGA-M showed a higher inflammatory response than Do-PLA-M/PCL. It was confirmed that the accumulation of acidic by-products due to the rapid biodegradation of PLGA induced a stronger inflammatory response. Summarizing the results, the application of Do-PLA-M and PCL hydrogel as a combination formulation can reduce the dosing frequency, increase treatment efficiency and convenience for Alzheimer's patients as a non-invasive injectable formulation with an extended drug release period.
more초록/요약
도네페질(Do)은 알츠하이머 질환 환자에게 경구 투여 제형으로 응용되고 있다. 하지만 부작용 유발 가능성과 함께 매일 투여해야 하는 불편함이 있다. 따라서 최근 서방형 약물 전달을 위해 도네페질과 함께 PLGA혹은 PLA로 제조한 마이크로스피어(Do-PLGA-M or Do-PLA-M)를 제조하여 주입형 제형으로서 연구되고 있다. 하지만 이러한 마이크로스피어 제형은 초기 과량 약물 방출 현상(initial burst)으로 인하여 보통 4주 이내로 약효 지속 시간이 끝나게 되며, 만성질환인 알츠하이머 환자에게 불편함을 초래한다. 따라서 이번 연구에서는 Do-PLA-M를 methoxy poly(ethylene glycol)-b-poly(ε-caprolactone) hydrogel (PCL)과 섞은 combination 제형(Do-PLA-M/PCL)으로 제조하였으며, 마이크로스피어의 initial burst를 억제하고, 약물 방출 기간을 연장하고자 하였다. 초음파 분사법을 이용하여 제조한 Do-PLGA-M, Do-PLA-M은 약 93% 이상의 높은 약물 봉입률, 수율과 함께 입자 크기가 매우 균일하게 제조되었다. 이는 기존의 마이크로스피어 제조 방식보다 효율이 뛰어나며, 최적화된 방법으로서 재현성이 증명되었다. Do-PLA-M/PCL은 성공적으로 합성된 PCL과 Do-PLA-M을 함께 상온에서 균일하게 섞이면서 쉽게 제조할 수 있었다. Do-PLA-M/PCL을 주입 용이성 및 온도감응성 평가를 진행하였을때 체내에 막히는 것 없이 쉽고 균일하게 주입할 수 있었다. 또한, 하이드로겔을 잘 형성하는 것을 통해 적절한 주입형 제형으로서 비침습적으로 환자에게 주입할 수 있음을 확인하였다. In vitro 및 in vivo 약물 방출 평가를 진행하였을 때 Do-PLGA-M보다 Do-PLA-M이 더 지속적으로 약물을 방출할 수 있었으며, matrix polymer의 특성에 따른 마이크로스피어의 물성 및 생분해 속도 차이에 의해 약물 방출 거동이 달라질 수 있음을 확인하였다. Do-PLA-M/PCL은 PCL 하이드로겔이 Do-PLA-M을 감싸는 barrier 역할을 함으로써 initial burst를 효과적으로 억제하였으며, Do-PLA-M의 생분해를 지연시켰다. 결과적으로 Do-PLA-M/PCL의 약물 방출 기간은 약 8주 이상으로 안정적으로 연장되었다. 도네페질이 담지된 주입형 제형(Do-PLGA-M, Do-PLA-M, Do-PLA-M/PCL)들의 생분해 속도를 비교하기 위해 micro-CT, SEM, NMR, GPC을 진행하였다. Do-PLGA-M이 가장 생분해 속도가 빨랐으며, Do-PLA-M/PCL이 가장 느렸다. 이러한 결과는 약물 방출 속도의 경향과 일치하였다. 또한 생체적합성 및 염증 발현도 평가를 진행하였을 때, Do-PLGA-M은 Do-PLA-M/PCL보다 더 높은 염증 반응을 보였으며, PLGA의 빠른 생분해로 인한 산성부산물의 축적이 더 강한 염증 반응을 유도함을 확인하였다. 결과를 종합하였을 때, Do-PLA-M과 PCL hydrogel을 combination 제형으로 응용하면 약물 방출 기간 연장과 함께 비침습적 주입형 제형으로서 투약 빈도를 줄이고 치료 효율 상승 및 알츠하이머 환자의 편의성을 증대시킬 수 있다.
more목차
1. Introduction 2
1.1. Alzheimer's disease 2
1.2. Drugs and mechanisms of action for the treatment of Alzheimer's disease 3
1.3. Drug delivery system and limitations for the treatment of Alzheimer's disease 4
1.4. Controlled release drug delivery system for the treatment of Alzheimer's disease 10
1.5. Thermoresponsive hydrogels 12
1.6. Microspheres 15
1.7. Manufacturing method of microsphere 16
1.8. Purpose and strategy of this works 18
2. Materials and method 24
2.1. Materials 24
2.2. Preparation of donepezil-loaded microsphere using monoaxial one-nozzle ultrasonic atomizer 25
2.3. Characterization and morphology evaluation of donepezil-loaded microspheres 26
2.4. Encapsulation efficiency of donepezil-loaded microspheres 27
2.5. Particle size measurement and stability test of donepezil-loaded microsphere 28
2.6. Mechanical properties of donepezil-loaded microsphere 29
2.7. Synthesis and characterization of PCL 29
2.8. Preparation and rheological characterization donepezil-loaded combination formulations 31
2.9. Uniformity evaluation of donepezil-loaded combination formulations during injection 32
2.10. Injectability and injection force evaluation of donepezil-loaded combination formulation 33
2.11. In vitro drug release of donepezil-loaded combination formulation 34
2.12. In vivo subcutaneous injection of donepezil-loaded combination formulation 35
2.13. In vivo drug release of donepezil-loaded combination formulation 37
2.14. In vivo biodegradation evaluation of donepezil-loaded combination formulation 38
2.15. In vivo physicochemical evaluation of donepezil-loaded combination formulation 39
2.16. In vivo biocompatibility evaluation of donepezil-loaded combination formulation 40
2.17. Statistical analyses 42
3. Result and discussion 43
3.1. Preparation and characterization of donepezil-loaded microsphere 43
3.2. Encapsulation and yield of donepezil-loaded microsphere 46
3.3. Comparison of particle size and distribution of donepezil-loaded microspheres 49
3.4. Stability evaluation of donepezil-loaded microsphere 53
3.5. Mechanical property of donepezil-loaded microsphere 55
3.6. Preparation and rheological characterization donepezil-loaded combination formulations 58
3.7. Uniformity evaluation of donepezil-loaded combination formulations during injection 64
3.8. Injectability and injection force evaluation of donepezil-loaded combination formulations 68
3.9. In vitro drug release of donepezil-loaded combination formulations 74
3.10. In vivo subcutaneous injection of donepezil-loaded combination formulations 78
3.11. In vivo drug release of donepezil-loaded combination formulations 86
3.12. In vivo biodegradation and morphology evaluation of donepezil-loaded combination formulations 95
3.13. In vivo biodegradation and physicochemical evaluation of donepezil-loaded combination formulations 101
3.14. In vivo biocompatibility evaluation of donepezil-loaded combination formulations 111
4. Conclusion 122
5. References 124
