Abstract：
:This paper presents in situ time-resolved drug mass fraction measurements in pressurised metered dose inhaler (PMDI) sprays, using a novel combination of synchrotron X-ray fluorescence and scattering. Equivalent suspension and solution formulations of ipratropium bromide in HFA-134a propellant were considered. Measurements were made both inside the expansion chamber behind the nozzle orifice, and in the first few millimeters of the spray where droplet and particle formation occur. We observed a consistent spike in drug mass fraction at the beginning of the spray when the first fluid exits the nozzle orifice. Approximately 20% of the total delivered dose exits the nozzle in the first 0.1 s of the spray. The drug mass fraction in the droplets immediately upon exiting the nozzle peaked at approximately 50% of the canister mass fraction, asymptoting to approximately 20% of the canister concentration. The effect is due to a change in the drug mass fraction inside the droplets, rather than changes in droplet size or distribution. The transient was found to originate inside the expansion chamber. We propose that this effect may be a major contributor to low delivery efficiency in PMDIs, and have important implications for oropharyngeal deposition and inhalation technique. This highlights the importance of expansion chamber and nozzle design on the structure of PMDI sprays, and indicates areas of focus that may lead to improvement in drug delivery outcomes.
journal_name
Int J Pharmjournal_title
International journal of pharmaceuticsauthors
Duke DJ,Scott HN,Kusangaya AJ,Kastengren AL,Matusik K,Young P,Lewis D,Honnery Ddoi
10.1016/j.ijpharm.2019.05.067subject
Has Abstractpub_date
2019-07-20 00:00:00pages
463-475eissn
0378-5173issn
1873-3476pii
S0378-5173(19)30427-2journal_volume
566pub_type
杂志文章abstract：:The permeation of cyproterone acetate (CPA) from Derma Membrane Structure (DMS) creams and liposomal formulations was investigated. Standard diffusion experiments with dermatomed porcine skin were performed. The cumulative CPA amount permeated of the DMS creams was between 2.9 and 6.8 microg/cm(2) within 48 h. By addi...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/s0378-5173(03)00180-7
更新日期：2003-06-04 00:00:00
abstract：:The purpose of this study was to construct isotretinoin-loaded SLN (IT-SLN) formulation with skin targeting for topical delivery of isotretinoin. PRECIROL ATO 5 was selected as the lipid of SLN. Tween 80 and soybean lecithin were used as the surfactants to stabilize SLN. The hot homogenization method was performed to ...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/j.ijpharm.2006.08.007
更新日期：2007-01-10 00:00:00
abstract：:It has been clearly demonstrated that ultraviolet radiation is harmful to the skin and can cause helioderma and cancers. There are different methods of combating ultraviolet radiation: sunscreens formulated with filters and/or screens as well as clothing. For this work, the authors studied different fabrics to evaluat...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/j.ijpharm.2010.06.022
更新日期：2010-09-15 00:00:00
abstract：:The aim of the present work was to evaluate the effect of sustained release of potassium chloride semi-solid matrices prepared with different kinds and added amounts of Gelucires by the in vitro dissolution test and in vivo oral absorption study, and compared with a commercial product (slow-K). The results indicating ...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/s0378-5173(02)00264-8
更新日期：2002-08-28 00:00:00
abstract：:The purpose of this work was to investigate distribution, transition, bioadhesion and release behaviors of insulin loaded pH-sensitive nanoparticles in the gut of rats, as well as the effects of viscosity agent on them. Insulin was labeled with fluorescein isothiocyanate (FITC). The FITC-insulin solution and FITC-insu...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/j.ijpharm.2006.08.040
更新日期：2007-02-01 00:00:00
abstract：:In the present paper the interaction between lambda carrageenan, a natural sulphated polysaccharide, and diltiazem HCl, a Ca channel blocking agent, was studied. Dialysis equilibria were performed to quantify the binding capacity of lambda carrageenan for diltiazem. The relevance of the interaction to hydrophilic matr...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/s0378-5173(00)00389-6
更新日期：2000-05-10 00:00:00
abstract：:To predict drug dissolution and understand the mechanisms of drug release from wax matrix dosage forms containing glyceryl monostearate (GM; a wax base), aminoalkyl methacrylate copolymer E (AMCE; a pH-dependent functional polymer), and acetaminophen (APAP; a model drug), we tried to derive a novel mathematical model ...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/j.ijpharm.2011.05.015
更新日期：2011-07-29 00:00:00
abstract：:The effects of inlet air humidity, granulation liquid feed rate and granulation liquid feed pulsing on the particle-size distribution of final granules were studied in a laboratory scale fluid-bed granulator using a central composite study design. The factors examined were modelled using three different particle-size ...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/j.ijpharm.2008.01.060
更新日期：2008-06-05 00:00:00
abstract：:The purpose of this study was to develop a novel featured and flexible methotrexate (MTX) formulation, in which MTX was physically entrapped and chemically conjugated in the same drug delivery system. A series of poloxamer-MTX (p-MTX) conjugates was synthesized, wherein MTX was grafted to poloxamer through an ester bo...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/j.ijpharm.2015.04.014
更新日期：2015-06-20 00:00:00
abstract：:Radiation sterilisation is a promising method to sterilise pharmaceutical products. However, this process is accompanied by a modification of odour due to volatile compounds formation. The origin of malodorous compounds produced during solid cefotaxime radiosterilisation has been investigated and several mechanisms ar...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/s0378-5173(98)00374-3
更新日期：1999-02-15 00:00:00
abstract：:Ethylene-vinyl acetate (EVA) is widely used as a membrane or matrix for transdermal drug delivery systems. In an attempt to determine the state of a drug in the EVA matrix, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and thermal analysis of the quinupramine-EVA matrix were carried out and ...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/j.ijpharm.2006.06.016
更新日期：2006-08-31 00:00:00
abstract：:The present investigation describes a procedure for the synthesis of a glycidyl methacrylated derivative from galactomannan, GA-MA, and the respective hydrogel formation. The galactomannan (GA), raw material, was purified and dissolved in DMSO. After dissolution, 4-dimethyl-amino-pyridine (DMAP) and glycidyl methacryl...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/j.ijpharm.2003.08.001
更新日期：2003-11-28 00:00:00
abstract：:This paper examines a perspective to use newly engineered nanomaterials as effective and safe carriers for gene therapy of cancer. Three different groups of cationic dendrimers (PAMAM, phosphorus, and carbosilane) were complexed with anticancer siRNA and the biophysical properties of the dendriplexes created were anal...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/j.ijpharm.2015.03.034
更新日期：2015-05-15 00:00:00
abstract：:The aim of this work was to investigate chitosomes, i.e. liposomes coated by a polyelectrolyte complex between chitosan (CH) and xantan gum (XG), as potential delivery system for oral administration of the protein C-phycocyanin. To this purpose several CH-XG-microcomplexes were prepared in aqueous lactic acid at diffe...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/j.ijpharm.2010.03.038
更新日期：2010-06-15 00:00:00
abstract：:This paper reports on measurements of the release characteristics of the model drug salbutamol base from a liquid crystalline vehicle across a non-rate limiting synthetic membrane. The measured passive release rates were compared with analogous behaviour: (i) when a penetration enhancer such as oleic acid was incorpor...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/s0378-5173(03)00108-x
更新日期：2003-05-12 00:00:00
abstract：:As with many other anti-cancer agents, docetaxel is a substrate for ATP-binding cassette transporters such as P-glycoprotein and its metabolism is mainly catalysed by CYP3A. In order to improve the oral bioavailability of docetaxel, a component of turmeric, curcumin, which can down-regulate the intestinal P-glycoprote...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/j.ijpharm.2010.08.015
更新日期：2010-10-31 00:00:00
abstract：:9-(2-phosphonyomethoxypropyl)adenine (PMPA) and AMD3100 are highly potent and selective antiretroviral agents. Since PMPA is negatively charged and AMD3100 positively charged at physiological pH, their transepithelial transport and their potential for oral drug delivery is very low. In this study, ion pair formation w...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/s0378-5173(99)00150-7
更新日期：1999-09-20 00:00:00
abstract：:Over the last few decades, hot melt extrusion (HME) has emerged as a successful technology for a broad spectrum of applications in the pharmaceutical industry. As indicated by multiple publications and patents, HME is mainly used for the enhancement of solubility and bioavailability of poorly soluble drugs. This revie...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章,评审
doi：10.1016/j.ijpharm.2017.10.056
更新日期：2018-01-15 00:00:00
abstract：:Meso-tetraphenyl porphine (mTPP) is a highly lipophilic, fluorescent porphyrin derivate and it is used as photosensitizer on the treatment of malign neoplasms. The aim of this study was to prepare mTPP loaded pluronic F127 and polyethylene glycol-distearoyl phosphatidylethanolamine (PEG(2000)-DSPE) micelles to evaluat...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/j.ijpharm.2006.09.030
更新日期：2007-03-06 00:00:00
abstract：:Poly(ethylene oxide)-block-poly(epsilon-caprolactone) (PEO-b-PCL) and newly developed poly(ethylene oxide)-block-poly(alpha-benzyl carboxylate epsilon-caprolactone) (PEO-b-PBCL) micelles were evaluated for the solubilization and delivery of cucurbitacin I and B, poorly water soluble inhibitors of signal transducer and...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/j.ijpharm.2007.06.032
更新日期：2008-01-22 00:00:00
abstract：:Various processing variables that can influence granulation characteristics of a lactose-based formulation were evaluated using a Plackett-Burman experimental design. These parameters were impeller speed, granulating solution addition rate, total amount of water added in the granulation step, wet massing time, moistur...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/s0378-5173(99)00445-7
更新日期：2000-03-30 00:00:00
abstract：:The hemocompatibility of nanoparticles is of critical importance for their systemic administration as drug delivery systems. Formulations of lipid-core nanocapsules, stabilized with polysorbate 80-lecithin and uncoated or coated with chitosan (LNC and LNC-CS), were prepared and characterized by laser diffraction (D[4,...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/j.ijpharm.2012.01.051
更新日期：2012-04-15 00:00:00
abstract：:Drug interactions with diosmectite, a gastric-protective drug, were studied in vitro using an artificial stomach-duodenum model. The behavior of neutral and ionisable drugs with pKa values ranging between 2 and 8 was monitored to determine the physicochemical characteristics of the interactions. The main neutral (digo...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/s0378-5173(99)00073-3
更新日期：1999-05-10 00:00:00
abstract：:The aim of this research was to investigate the molecular interactions occurring in the formulation of non-ionic surfactant based vesicles composed monopalmitoyl glycerol (MPG), cholesterol (Chol) and dicetyl phosphate (DCP). In the formulation of these vesicles, the thermodynamic attributes and surfactant interaction...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/j.ijpharm.2013.11.063
更新日期：2014-01-30 00:00:00
abstract：:Viscous liquid degradable polymers have advantages as drug depots for sustained protein delivery. We have created a new aliphatic polycarbonate for this purpose, poly(trimethylene carbonate-co-5-hydroxy trimethylene carbonate), which upon degradation retains a near neutral micro-environmental pH. As such, this copolym...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/j.ijpharm.2020.119965
更新日期：2020-11-30 00:00:00
abstract：:The infection of bone and bone marrow is called osteomyelitis. Treatment is difficult since antibiotics can not reach with enough concentration to the infected area. For the first time in this study, we have developed gentamicin-loaded magnetic gelatin nanoparticles (GMGNPs) for nanocarrier-mediated and magnetically t...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/j.ijpharm.2020.119999
更新日期：2021-01-05 00:00:00
abstract：:Formulation of poorly water-soluble drugs in the most stable dosage form for oral delivery perhaps presents the greatest challenge to pharmaceutical industry. Physical transformation of drug substance into its more soluble but metastable amorphous form is one of the approaches for improving dissolution rate of such dr...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/j.ijpharm.2004.06.009
更新日期：2004-09-10 00:00:00
abstract：:The bioavailability of ibuprofen from matrix mini-tablets based on microcrystalline wax and a starch derivative was tested. An oral dose of 300 mg of ibuprofen was administered to healthy volunteers (n=8) in a randomized cross-over study design either as a commercial matrix formulation (Ibu-Slow 600) or as mini-tablet...
journal_title：International journal of pharmaceutics
pub_type： 临床试验,杂志文章,随机对照试验
doi：10.1016/s0378-5173(00)00549-4
更新日期：2000-11-04 00:00:00
abstract：:N-(2-Hydroxypropyl) methacrylamide (HPMA) copolymer has been extensively studied as drug carrier for tumor therapy. Due to the Enhanced Permeability and Retention (EPR) effect, HPMA copolymer drug conjugates are able to be passively accumulated in the tumor site. Currently, efficient uptake of this polymeric system by...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/j.ijpharm.2017.12.018
更新日期：2018-01-30 00:00:00
abstract：:Oral absorption of lopinavir (LPV) is limited due to P-glycoprotein (P-gp) and multidrug resistance-associated protein2 (MRP2) mediated efflux by intestinal epithelial cells. Moreover, LPV is extensively metabolized by CYP3A4 enzymes. In the present study, dipeptide prodrug approach was employed to circumvent efflux p...
journal_title：International journal of pharmaceutics
pub_type： 杂志文章
doi：10.1016/j.ijpharm.2014.09.035
更新日期：2014-12-10 00:00:00
