Pharmaceutical Research

, Volume 34, Issue 12, pp 2787–2797 | Cite as

In Vitro-In Vivo Relationship of Amorphous Insoluble API (Progesterone) in PLGA Microspheres

  • Chenguang Pu
  • Qiao Wang
  • Hongjuan Zhang
  • Jingxin Gou
  • Yuting Guo
  • Xinyi Tan
  • Bin Xie
  • Na Yin
  • Haibing He
  • Yu Zhang
  • Yanjiao WangEmail author
  • Tian YinEmail author
  • Xing Tang
Research Paper



The mechanism of PRG release from PLGA microspheres was studied and the correlation of in vitro and in vivo analyses was assessed.


PRG-loaded microspheres were prepared by the emulsion-evaporate method. The physical state of PRG and microstructure changings during the drug release period were evaluated by powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM) respectively. Pharmacokinetic studies were performed in male Sprague-Dawley rats, and the in vivo-in vitro correlation (IVIVC) was established by linear fitting of the cumulative release (%) in vitro and fraction of absorption (%) in vivo.


PXRD results indicated recrystallization of PRG during release. The changes of microstructure of PRG-loaded microspheres during the release period could be observed in SEM micrographs. Pharmacokinetics results performed low burst-release followed a steady-released manner. The IVIVC assessment exhibited a good correlation between vitro and in vivo.


The burst release phase was caused by diffusion of amorphous PRG near the surface, while the second release stage was impacted by PRG-dissolution from crystal depots formed in microspheres. The IVIVC assessment suggests that the in vitro test method used in this study could predict the real situation in vivo and is helpful to study the release mechanism in vivo.


amorphous crystal depot IVIVC PLGA microspheres release mechanism 



Active pharmaceutical ingredient




Absorption fraction




In vitro and in vivo correlation


Liquid chromatography–mass spectrometry/mass spectrometry




Molecular weight










Polyvinyl alcohol


Powder x-ray diffraction




Sprague – Dawley


Sodium dodecyl sulfate


Scanning electron microscopy


Saline injection


Glass transition temperature



The authors wish to thank Amanda Pearce for linguistic assistance. This work was supported by the National Natural Science Foundation of China No. 81673378.


  1. 1.
    Wang Y, Burgess DJ. Microsphere technologies. In: Wrightand JC, Burgess DJ, editors. Long acting injections and implants. Boston: Springer US; 2012. p. 167–94.CrossRefGoogle Scholar
  2. 2.
    D'Souza SS, Faraj JA, DeLuca PP. A model-dependent approach to correlate accelerated with real-time release from biodegradable microspheres. AAPS PharmSciTech. 2005;6:E553–64.CrossRefGoogle Scholar
  3. 3.
    Mollo AR, Corrigan OI. Effect of poly-hydroxy aliphatic ester polymer type on amoxycillin release from cylindrical compacts. Int J Pharm. 2003;268:71–9.CrossRefGoogle Scholar
  4. 4.
    Wang J, Wang BA, Schwendeman SP. Characterization of the initial burst release of a model peptide from poly(D,L-lactide-co-glycolide) microspheres. J Control Release. 2002;82:289–307.CrossRefGoogle Scholar
  5. 5.
    Schwendeman SP, Reinhold III SE, Kang J. Self -healing polymers microencapsulate biomacromolecules without organic solvents by Reinhold, Samuel E., Iii, Ph.D., UNIVERSITY OF MICHIGAN, 2009;212:3382334 Methods.Google Scholar
  6. 6.
    Reinhold III SE. Self-healing polymers microencapsulate biomacromolecules without organic solvents. Angew Chem Int Ed. 2009;51:10800–3.CrossRefGoogle Scholar
  7. 7.
    Zhu G, Mallery SR, Schwendeman SP. Stabilization of proteins encapsulated in injectable poly (lactide- co-glycolide). Nat Biotechnol. 2000;18:52.CrossRefGoogle Scholar
  8. 8.
    Pérez C, Griebenow K. Effect of salts on lysozyme stability at the water-oil interface and upon encapsulation in poly(lactic-co-glycolic) acid microspheres. Biotechnol Bioeng. 2003;82:825–32.CrossRefGoogle Scholar
  9. 9.
    Schwendeman SP, Cardamone M, Klibanov A, Langer R, Brandon MR. Stability of proteins and their delivery from biodegradable polymer microspheres. 1996.Google Scholar
  10. 10.
    Li S, Mccarthy S. Further investigations on the hydrolytic degradation of poly (DL-lactide). Biomaterials. 1999;20:35.CrossRefGoogle Scholar
  11. 11.
    Dunne M, Corrigan I, Ramtoola Z. Influence of particle size and dissolution conditions on the degradation properties of polylactide-co-glycolide particles. Biomaterials. 2000;21:1659–68.CrossRefGoogle Scholar
  12. 12.
    Park TG. Degradation of poly(lactic-co-glycolic acid) microspheres: effect of copolymer composition. Biomaterials. 1995;16:1123–30.CrossRefGoogle Scholar
  13. 13.
    Park TG. Degradation of poly(d,l-lactic acid) microspheres: effect of molecular weight. J Control Release. 1994;30:161–73.CrossRefGoogle Scholar
  14. 14.
    Rumondor ACF, Wikström H, Eerdenbrugh BV, Taylor LS. Understanding the tendency of amorphous solid dispersions to undergo amorphous-amorphous phase separation in the presence of absorbed moisture. AAPS PharmSciTech. 2011;12:1209.CrossRefGoogle Scholar
  15. 15.
    Alonzo DE, Zhang GG, Zhou D, Gao Y, Taylor LS. Understanding the behavior of amorphous pharmaceutical systems during dissolution. Pharm Res Dordr. 2010;27:608–18.CrossRefGoogle Scholar
  16. 16.
    Xie T, Taylor LS. Dissolution performance of high drug loading celecoxib amorphous solid dispersions formulated with polymer combinations. Pharm Res Dordr. 2016;33:739–50.CrossRefGoogle Scholar
  17. 17.
    Shen J, Choi S, Qu W, Wang Y, Burgess DJ. In vitro-in vivo correlation of parenteral risperidone polymeric microspheres. 2015.CrossRefGoogle Scholar
  18. 18.
    Doty AC, Weinstein DG, Hirota K, Olsen KF, Ackermann R, Wang Y, et al. Mechanisms of in vivo release of triamcinolone acetonide from PLGA microspheres. J Control Release. 2017;256:19–25.CrossRefGoogle Scholar
  19. 19.
    Su ZX, Shi YN, Teng LS, Li X, Wang LX, Meng QF, et al. Biodegradable poly(D, L-lactide-co-glycolide) (PLGA) microspheres for sustained release of risperidone: zero-order release formulation. Pharm Dev Technol. 2011;16:377.CrossRefGoogle Scholar
  20. 20.
    Xie X, Li Z, Ling Z, Qiang C, Yang Y, Hui Z, et al. A novel accelerated in vitro release method to evaluate the release of thymopentin from PLGA microspheres. Pharm Dev Technol. 2015;20:633.CrossRefGoogle Scholar
  21. 21.
    Sun LL, Meng FH, Yu L, Liu JY, Guo JF, Zhang ZX. Determination of progesterone in rat plasma by LC-MS/MS. J Int Pharm Res. 2015;42:107–11.Google Scholar
  22. 22.
    Hwang SS, Bayne W, Theeuwes F. In vivo evaluation of controlled-release products. J Pharm Sci-Us. 1993;82:1145.CrossRefGoogle Scholar
  23. 23.
    Wagnerand JG, Nelson E. Per cent absorbed time plots derived from blood level and/or urinary excretion data. J Pharm Sci-Us. 1963;52:610.CrossRefGoogle Scholar
  24. 24.
    Woo BH, Kostanski JW, Gebrekidan S, Dani BA, Thanoo BC, Deluca PP. Preparation, characterization and in vivo evaluation of 120-day poly(d,l-lactide) leuprolide microspheres. J Control Release. 2001;75:307–15.CrossRefGoogle Scholar
  25. 25.
    Raman C, Berkland C, Kim K, Pack DW. Modeling small-molecule release from PLG microspheres: effects of polymer degradation and nonuniform drug distribution. J Control Release. 2005;103:149–58.CrossRefGoogle Scholar
  26. 26.
    Bodmeier R, Mcginity JW. Polylactic acid microspheres containing quinidine base and quinidine sulphate prepared by the solvent evaporation technique. I. Methods and morphology. J Microencapsul. 1987;4:279–88.CrossRefGoogle Scholar
  27. 27.
    Nilkumhang S, Alhnan MA, Mcconnell EL, Basit AW. Drug distribution in enteric microparticles. Int J Pharm. 2009;379:1–8.CrossRefGoogle Scholar
  28. 28.
    Singh A, Van den Mooter G. Spray drying formulation of amorphous solid dispersions. Adv Drug Deliv Rev. 2016;100:27–50.CrossRefGoogle Scholar
  29. 29.
    Mooter GVD, Wuyts M, Blaton N, Busson R, Grobet P, Augustijns P, Kinget R. Physical stabilisation of amorphous ketoconazole in solid dispersions with polyvinylpyrrolidone K252001.Google Scholar
  30. 30.
    Kestur US, Taylor LS. Role of polymer chemistry in influencing crystal growth rates from amorphous felodipine. CrystEngComm. 2010;12:2390–7.CrossRefGoogle Scholar
  31. 31.
    Kestur US, Eerdenbrugh BV, Taylor LS. Influence of polymer chemistry on crystal growth inhibition of two chemically diverse organic molecules. CrystEngComm. 2011;13:6712–8.CrossRefGoogle Scholar
  32. 32.
    Peppas NA. Analysis of Fickian and non-Fickian drug release from polymers. 1985.Google Scholar
  33. 33.
    Fredenberg S, Wahlgren M, Reslow M, Axelsson A. The mechanisms of drug release in poly(lactic-co-glycolic acid)-based drug delivery systems—a review. Int J Pharm. 2011;415:34–52.CrossRefGoogle Scholar
  34. 34.
    Blasi P, D'Souza SS, Selmin F, Deluca PP. Plasticizing effect of water on poly(lactide-co-glycolide). J Control Release. 2005;108:1.CrossRefGoogle Scholar
  35. 35.
    Hancock BC, Parks M. What is the true solubility advantage for amorphous pharmaceuticals? Pharm Res Dordr. 2000;17:397–404.CrossRefGoogle Scholar
  36. 36.
    Ricci M, Blasi P, Giovagnoli S, Rossi C, Macchiarulo G, Luca G, Basta G, Calafiore R. Ketoprofen controlled release from composite microcapsules for cell encapsulation: effect on post-transplant acute inflammation. 2005.Google Scholar
  37. 37.
    Yamaguchi Y, Takenaga M, Kitagawa A, Ogawa Y, Mizushima Y, Igarashi R. Insulin-loaded biodegradable PLGA microcapsules: initial burst release controlled by hydrophilic additives. 2002.CrossRefGoogle Scholar
  38. 38.
    Gupta PK, Mehta RC, Douglas RH, Deluca PP. In vivo evaluation of biodegradable progesterone microspheres in mares. Pharm Res Dordr. 1992;9:1502–6.CrossRefGoogle Scholar
  39. 39.
    Anderson JM. In vitro and in vivo monocyte, macrophage, foreign body giant cell, and lymphocyte interactions with biomaterials. Biomaterials. 2009;127(2):225-244.Google Scholar
  40. 40.
    Zolnik BS, Burgess DJ. Evaluation of in vivo – in vitro release of dexamethasone from PLGA microspheres. J Control Release. 2008;127:137.CrossRefGoogle Scholar
  41. 41.
    Uppoor VR. Regulatory perspectives on in vitro (dissolution)/in vivo (bioavailability) correlations. J Control Release. 2001;72:127–32.CrossRefGoogle Scholar
  42. 42.
    Spenlehauer G, Vert M, Benoit JP, Boddaert A. In vitro and In vivo degradation of poly(D,L lactide/glycolide) type microspheres made by solvent evaporation method. Biomaterials. 1989;10:557.CrossRefGoogle Scholar
  43. 43.
    Tracy MA, Ward KL, Firouzabadian L, Wang Y, Dong N, Qian R, et al. Factors affecting the degradation rate of poly(lactide-co-glycolide) microspheres in vivo and in vitro. Biomaterials. 1999;20:1057.CrossRefGoogle Scholar
  44. 44.
    Dutta S, Qiu Y, Samara E, Cao G, Granneman GR. Once-a-day extended-release dosage form of divalproex sodium III: development and validation of a Level A in vitro-in vivo correlation (IVIVC). J Pharm Sci-Us. 2005;94:1949–56.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2017

Authors and Affiliations

  • Chenguang Pu
    • 1
  • Qiao Wang
    • 1
  • Hongjuan Zhang
    • 1
  • Jingxin Gou
    • 1
  • Yuting Guo
    • 1
  • Xinyi Tan
    • 1
  • Bin Xie
    • 1
  • Na Yin
    • 1
  • Haibing He
    • 1
  • Yu Zhang
    • 1
  • Yanjiao Wang
    • 1
    Email author
  • Tian Yin
    • 2
    Email author
  • Xing Tang
    • 1
  1. 1.School of PharmacyShenyang Pharmaceutical UniversityShenyangChina
  2. 2.School of Functional food and WineShenyang Pharmaceutical UniversityShenyangChina

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