Abstract：
:Two generalized modes of erosion kinetics, that is, the power law mode and root type mode, respectively, were found to be able to better describe the reported weight loss data compared to the existing linear mode, for commonly used surface-eroding polymer microspheres. Based on the newly identified modes, a set of drug release models were developed by extending the existing model. Model validation was achieved by comparing the model predictions to the reported experimental data for surface-eroding polymer microspheres (poly(ortho esters) and polyanhydrides), and good consistency was found. Parameter investigation was conducted to reveal the effects of various important parameters (the dimensionless ratio between diffusion and erosion rates (Er), the dimensionless ratio between erosion and dissolution rates (p), the dimensionless drug loading concentration (q), and the fitting parameter of erosion kinetics (a)) on drug release behavior, which has rarely been examined previously. In general, the effects of these parameters were more significant for an earlier stage, and p, q, and a could effectively vary the drug release percentage. Design-of-experiments-based sensitivity analysis was further carried out and it was found that the most sensitive parameters were p (2.97%) and q (2.97%) for the cases of the power law mode, while it was a (-7.07%) for the cases of the root type mode. The information from the parameter investigation and sensitivity analysis could serve as a straightforward data bank for the practical designing of drug delivery processes. The proposed models are potential mathematical frameworks for the designing of drugs that are based on surface-eroding polymer microspheres in the future.
journal_name
J Pharm Scijournal_title
Journal of pharmaceutical sciencesauthors
You S,Yang Z,Wang CHdoi
10.1016/j.xphs.2016.04.002subject
Has Abstractpub_date
2016-06-01 00:00:00pages
1934-1946issue
6eissn
0022-3549issn
1520-6017pii
S0022-3549(16)41370-5journal_volume
105pub_type
杂志文章abstract：:The stability of aqueous solutions of luteinizing hormone-releasing hormone (LHRH) after extended storage at various temperatures was investigated using a newly developed HPLC assay and an in vitro dispersed pituitary cell culture bioassay. Good correlations were obtained between the potency obtained by HPLC and bioas...
journal_title：Journal of pharmaceutical sciences
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doi：10.1002/jps.2600730628
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journal_title：Journal of pharmaceutical sciences
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journal_title：Journal of pharmaceutical sciences
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doi：10.1002/jps.2600660435
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doi：10.1002/jps.2600690113
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journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600661223
更新日期：1977-12-01 00:00:00
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journal_title：Journal of pharmaceutical sciences
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doi：10.1002/jps.2600700212
更新日期：1981-02-01 00:00:00
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journal_title：Journal of pharmaceutical sciences
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更新日期：2005-03-01 00:00:00
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journal_title：Journal of pharmaceutical sciences
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doi：10.1016/j.xphs.2020.12.037
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journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600670542
更新日期：1978-05-01 00:00:00
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journal_title：Journal of pharmaceutical sciences
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doi：10.1016/j.xphs.2019.02.017
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journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600730531
更新日期：1984-05-01 00:00:00
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journal_title：Journal of pharmaceutical sciences
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doi：10.1002/jps.24331
更新日期：2015-04-01 00:00:00
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journal_title：Journal of pharmaceutical sciences
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doi：10.1002/jps.22349
更新日期：2011-03-01 00:00:00
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journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600670728
更新日期：1978-07-01 00:00:00
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journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600690122
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更新日期：2011-12-01 00:00:00
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journal_title：Journal of pharmaceutical sciences
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doi：10.1002/jps.2600641229
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abstract：:Nonionic block copolymers are surfactants synthesized using propylene oxide and ethylene oxide, and they can be designed so that individual copolymers have unique vaccine adjuvant properties. We have designed and produced nonionic block copolymers based on high molecular weight (MW), 9-15 kDA, cores of poly(oxypropyle...
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abstract：:The poor membrane permeability and oral bioavailability of the iron chelating agent deferoxamine (DFO) mesylate result from the low octanol/water partition coefficient and high aqueous solubility. With the ultimate aim to improve biomembrane permeability while retaining the iron-binding ability of DFO, a series of mor...
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更新日期：2000-12-01 00:00:00
abstract：:A rotating-basket apparatus for dissolution testing of veterinary bolus tablets was designed and constructed. Sulfamethazine boluses containing different disintegrating agents were evaluated in vitro and by blood level data following administration to cattle. The dissolution t50 and various pharmacokinetic parameters ...
journal_title：Journal of pharmaceutical sciences
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doi：10.1002/jps.2600651231
更新日期：1976-12-01 00:00:00
abstract：:Application of ultrasound enhances transdermal transport of drugs (sonophoresis). The enhancement may result from enhanced diffusion due to ultrasound-induced skin alteration and/or from forced convection. To understand the relative roles played by these two mechanisms in low-frequency sonophoresis (LFS, 20 kHz), a th...
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更新日期：2001-05-01 00:00:00
