Abstract：
PURPOSE:Polyesters with hydrophilic domains, i.e., poly(D,L-lactic-co-glycolic-co-hydroxymethyl glycolic acid) (PLGHMGA) and a multiblock copolymer of poly(ε-caprolactone)-PEG-poly(ε-caprolactone) and poly(L-lactide) ((PC-PEG-PC)-(PL)) are expected to cause less acylation of encapsulated peptides than fully hydrophobic matrices. Our purpose is to assess the extent and sites of acylation of octreotide loaded in microspheres using tandem mass spectrometry analysis. METHODS:Octreotide loaded microspheres were prepared by a double emulsion solvent evaporation technique. Release profiles of octreotide from hydrophilic microspheres were compared with that of PLGA microspheres. To scrutinize the structural information and localize the actual modification site(s) of octreotide, liquid chromatography ion-trap mass spectrometry (LC-ITMS) was performed on the acylated adducts. RESULTS:Hydrophilic microspheres showed less acylated adducts in comparison with PLGA microspheres. LC-MS/MS showed that besides the N-terminus and primary amine of lysine, the primary hydroxyl of the end group of octreotide was also subjected to acylation. Nucleophilic attack of the peptide can also occur to the carbamate bond presented in (PC-PEG-PC)-(PL) since 1,4-butanediisocyanate was used as the chain extender. CONCLUSIONS:Hydrophilic polyesters are promising systems for controlled release of peptide because substantially less acylation occurs in microspheres based on these polymers. LC-ITMS provided detailed structural information of octreotide modifications via mass analysis of ion fragments.
journal_name
Pharm Resjournal_title
Pharmaceutical researchauthors
Shirangi M,Hennink WE,Somsen GW,van Nostrum CFdoi
10.1007/s11095-015-1685-3subject
Has Abstractpub_date
2015-09-01 00:00:00pages
3044-54issue
9eissn
0724-8741issn
1573-904Xjournal_volume
32pub_type
杂志文章abstract：PURPOSE:The combination of morphine and gabapentin seems promising for the treatment of postoperative and neuropathic pain. Despite the well characterised pharmacodynamic interaction, little is known about possible pharmacokinetic interactions. The aim of this study was to evaluate whether co-administration of the two ...
journal_title：Pharmaceutical research
pub_type： 杂志文章
doi：10.1007/s11095-016-1988-z
更新日期：2016-11-01 00:00:00
abstract：PURPOSE:Carboxylesterases are important in the detoxification of drugs, pesticides and other xenobiotics. This study was to evaluate a series of substrates and inhibitors for characterizing these enzymes. METHODS:A series of novel aliphatic esters and thioesters were used in spectral assays to monitor human, murine an...
journal_title：Pharmaceutical research
pub_type： 杂志文章
doi：10.1023/a:1016071311190
更新日期：1996-10-01 00:00:00
abstract：PURPOSE:To investigate, for the first time, the performance of a dry powder inhaler (DPI, Aerolizer(®)) in the case of a model drug (i.e. albuterol sulphate) formulated with spray dried mannitol carrier particles with homogeneous shape and solid-state form but different sizes. METHODS:Spray dried mannitol (SDM) partic...
journal_title：Pharmaceutical research
pub_type： 杂志文章
doi：10.1007/s11095-013-1132-2
更新日期：2014-01-01 00:00:00
abstract：PURPOSE:Exenatide, a potent insulinotropic agent, can be used for the treatment of non-insulin-dependent diabetes mellitus. However, the need for frequent injections seriously limits its therapeutic utility. The aim of present report was to develop an orally available exenatide formulation using goblet cell-targeting n...
journal_title：Pharmaceutical research
pub_type： 杂志文章
doi：10.1007/s11095-014-1513-1
更新日期：2015-03-01 00:00:00
abstract：PURPOSE:To provide a systematic biophysical approach towards a better understanding of impact of conjugation chemistry on higher order structure and physical stability of an antibody drug conjugate (ADC). METHODS:ADC was prepared using thiol-maleimide chemistry. Physical stabilities of ADC and its parent IgG1 mAb were...
journal_title：Pharmaceutical research
pub_type： 杂志文章
doi：10.1007/s11095-013-1274-2
更新日期：2014-07-01 00:00:00
abstract：:Nucleoside transporters play a critical role in the absorption, disposition, and targeting of therapeutically used nucleosides and nucleoside analogs. This review is focused on the Na(+)-dependent, concentrative nucleoside transporters which are found in a variety of cells including renal, intestinal and hepatic epith...
journal_title：Pharmaceutical research
pub_type： 杂志文章,评审
doi：10.1023/a:1012113931332
更新日期：1997-11-01 00:00:00
abstract：PURPOSE:To evaluate the impact of intestinal first-pass metabolism (Fg) by cytochrome P4503A (CYP3A) and uridine 5'-diphosphate-glucuronosyltransferases (UGT) on in vivo oral absorption of their substrate drugs. METHODS:CYP3A and UGT substrates were orally administered to portal-vein cannulated (PV) rats to evaluate t...
journal_title：Pharmaceutical research
pub_type： 杂志文章
doi：10.1007/s11095-014-1489-x
更新日期：2015-02-01 00:00:00
abstract：:Biotherapeutics, including recombinant or plasma-derived human proteins and antibody-based molecules, have emerged as an important class of pharmaceuticals. Aggregation and immunogenicity are among the major bottlenecks during discovery and development of biotherapeutics. Computational tools that can predict aggregati...
journal_title：Pharmaceutical research
pub_type： 杂志文章
doi：10.1007/s11095-011-0414-9
更新日期：2011-05-01 00:00:00
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journal_title：Pharmaceutical research
pub_type： 杂志文章
doi：10.1023/a:1018910114436
更新日期：1994-01-01 00:00:00
abstract：PURPOSE:Monoamine oxidases (MAOs) are non-CYP enzymes that contribute to systemic elimination of therapeutic agents, and localized on mitochondrial membranes. The aim of the present study was to validate quantitative estimation of metabolic clearance of MAO substrate drugs using human liver microsomes (HLMs). METHODS:...
journal_title：Pharmaceutical research
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doi：10.1007/s11095-017-2140-4
更新日期：2017-06-01 00:00:00
abstract：PURPOSE:Empirical formulae relate the mean size of primary droplets from jet and ultrasonic nebulizers to a fluid's physicochemical properties. Although the size selective "filtering" effects of baffling and evaporation may modify the secondary aerosol produced, this research sought to evaluate whether viscosity and su...
journal_title：Pharmaceutical research
pub_type： 杂志文章
doi：10.1023/a:1016205520044
更新日期：1995-11-01 00:00:00
abstract：:The pulmonary deposition and pharmacokinetics of human growth hormone (hGH), administered by aerosol and instillate, in formulations containing 99mTc-DTPA (for gamma scintigraphic imaging) have been studied in five male New Zealand White rabbits. Gamma scintigraphy indicated that the peripheral:central deposition tend...
journal_title：Pharmaceutical research
pub_type： 杂志文章
doi：10.1023/a:1016292232513
更新日期：1995-03-01 00:00:00
abstract：PURPOSE:There is evidence that cholesterol affects the ATPase and transport functions of P-glycoprotein (P-gp). To study the influence of cholesterol on P-gp in a well defined lipid environment, we reconstituted P-gp in egg phosphatidylcholine (PhC) and PhC/cholesterol proteoliposomes with negligible residual amounts o...
journal_title：Pharmaceutical research
pub_type： 杂志文章
doi：10.1007/s11095-007-9326-0
更新日期：2007-11-01 00:00:00
abstract：:Fibers were spun by the downward configuration of the wet spinning technique. This configuration is capable of encapsulating nonspherical and/or coarse particles. We examined encapsulation of propranolol hydrochloride and the ability of the fibers to act as a sustained-release delivery system for propranolol hydrochlo...
journal_title：Pharmaceutical research
pub_type： 杂志文章
doi：10.1023/a:1015982521706
更新日期：1989-12-01 00:00:00
abstract：PURPOSE:Iontophoresis was employed for enhancing the transdermal delivery of acyclovir through nude mouse skin in vitro, with the aim of understanding the mechanisms responsible for drug transport, in order to properly set the conditions of therapeutical application. METHODS:Experiments were done in horizontal diffusi...
journal_title：Pharmaceutical research
pub_type： 杂志文章
doi：10.1023/a:1016284815501
更新日期：1995-11-01 00:00:00
abstract：PURPOSE:In the present study we investigated the root-cause of an interference signal (100-200 nm) of sugar-containing solutions in dynamic light scattering (DLS) and nanoparticle tracking analysis (NTA) and its consequences for the analysis of particles in biopharmaceutical drug products. METHODS:Different sugars as ...
journal_title：Pharmaceutical research
pub_type： 杂志文章
doi：10.1007/s11095-015-1634-1
更新日期：2015-07-01 00:00:00
abstract：PURPOSE:Synthetic hydrogels fabricated from photopolymerization are attractive for tissue engineering for their controlled macroscopic properties, the ability to incorporate biological functionalities, and cell encapsulation. The goal of the present study was to exploit the attractive features of synthetic hydrogels to...
journal_title：Pharmaceutical research
pub_type： 杂志文章
doi：10.1007/s11095-008-9619-y
更新日期：2008-10-01 00:00:00
abstract：PURPOSE:The relationship between rat intestinal permeability (Papp) of a range of hydrophilic probe molecules and probe geometry was examined. METHODS:Molecules studies included mannitol, the polyethylene glycols (PEGs) 400, 900, and 4000, the dextran conjugated dye Texas Red (MW 3000) and the polysaccharide inulin (M...
journal_title：Pharmaceutical research
pub_type： 杂志文章
doi：10.1023/a:1016091915733
更新日期：1996-10-01 00:00:00
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journal_title：Pharmaceutical research
pub_type： 杂志文章
doi：10.1023/a:1011994230346
更新日期：1998-04-01 00:00:00
abstract：PURPOSE:The objective of this study was to develop and evaluate a pulsatile drug delivery system based on an impermeable capsule body filled with drug and an erodible plug placed in the opening of the capsule body. METHODS:The erodible plugs were either prepared by direct compression followed by placing the tablets in...
journal_title：Pharmaceutical research
pub_type： 杂志文章
doi：10.1023/a:1011940718534
更新日期：1998-03-01 00:00:00
abstract：PURPOSE:To study the miscibility of proteins and polymer excipients in frozen solutions and freeze-dried solids as protein formulation models. METHODS:Thermal profiles of frozen solutions and freeze-dried solids containing various proteins (lysozyme, ovalbumin, BSA), nonionic polymers (Ficoll, polyvinylpyrrolidone [PV...
journal_title：Pharmaceutical research
pub_type： 杂志文章
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更新日期：2000-10-01 00:00:00
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journal_title：Pharmaceutical research
pub_type： 杂志文章
doi：10.1023/a:1018956516640
更新日期：1992-01-01 00:00:00
abstract：PURPOSE:Herein we report the discovery of a group of derivatized alpha-amino acids that increase the oral bioavailability of sodium cromolyn. METHODS:We prepared three N-acylated alpha-amino acids and used these compounds to demonstrate the oral delivery of cromolyn in an in vivo rat model. In vitro experiments, inclu...
journal_title：Pharmaceutical research
pub_type： 杂志文章
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更新日期：1996-02-01 00:00:00
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journal_title：Pharmaceutical research
pub_type： 杂志文章
doi：10.1023/a:1016486910719
更新日期：2002-07-01 00:00:00
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journal_title：Pharmaceutical research
pub_type： 杂志文章
doi：10.1007/s11095-012-0885-3
更新日期：2013-03-01 00:00:00
abstract：PURPOSE:Low temperature sensitive liposome (LTSL) encapsulated docetaxel were combined with mild hyperthermia (40-42°C) to investigate in vivo biodistribution and efficacy against a castrate resistant prostate cancer. METHOD:Female athymic nude mice with human prostate PC-3 M-luciferase cells grown subcutaneously into...
journal_title：Pharmaceutical research
pub_type： 杂志文章
doi：10.1007/s11095-016-1971-8
更新日期：2016-10-01 00:00:00
abstract：PURPOSE:Indocyanine green (ICG), an FDA-approved near infrared (NIR) dye, has potential application as a contrast agent for tumor detection. Because ICG binds strongly to plasma proteins and exhibits aqueous, photo, and thermal instability, its current applications are largely limited to monitoring blood flow. To addre...
journal_title：Pharmaceutical research
pub_type： 杂志文章
doi：10.1007/s11095-010-0190-y
更新日期：2010-09-01 00:00:00
abstract：PURPOSE:Penetration enhancers (PEs) enhancing efficacy depends on two processes: PEs release from patches and action on skin. Compared with their action on skin, PEs release process was poorly understood. Therefore, the purpose of this study was to make a mechanistic understanding of PEs release from acrylic pressure-s...
journal_title：Pharmaceutical research
pub_type： 杂志文章
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更新日期：2020-08-13 00:00:00
abstract：PURPOSE:We compared cationic, polyamine-coated microparticles (MPs) and anionic, protein-coated MPs with respect to their phagocytosis and phagosomal fate in dendritic cells (DCs) and macrophages (Mphi). METHODS:Polystyrene MPs were surface modified by covalent coupling with fluorescein isothiocyanate-labeled polyamin...
journal_title：Pharmaceutical research
pub_type： 杂志文章
doi：10.1023/a:1022271020390
更新日期：2003-02-01 00:00:00
abstract：PURPOSE:LY3015014 is a humanized immunoglobulin G4 (IgG4) monoclonal antibody that binds to the catalytic domain of PCSK9 and reduce low-density lipoprotein cholesterol (LDL-C) in patients with hypercholesterolemia that is poorly controlled by maximally tolerated statin therapy. The objective of this pharmacokinetic/ph...
journal_title：Pharmaceutical research
pub_type： 杂志文章
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更新日期：2017-01-01 00:00:00
