Advertisement

Topics

The use of permeation tube device and the development of empirical formula for accurate permeation rate.

Summary of "The use of permeation tube device and the development of empirical formula for accurate permeation rate."

A series of laboratory experiments were conducted to assess the accuracy of permeation tube (PT) devices using a calibration gas generator system to measure permeation rate (PR) of volatile organic compounds (VOCs). Calibration gas standards of benzene, toluene, and m-xylene (BTX) were produced from PTs at varying flow rates (FR) of 20-1200mLmin(-1) and constant temperature (30°C). Results indicate that changes in flow rate greatly affected the permeation rate of each VOC at this temperature. This paper presents experimental approaches to accurately measure actual permeation rate (APR) and the derivation of empirical equations for predicted permeation rate (PPR). If the magnitude of bias is defined as the difference between PPR and the manufacturer's permeation rate (MPR), the bias was typically 19-40% for toluene (T) and 31-54% for m-xylene (X). Benzene (B) exhibited the least bias of 1.4-18.8%, nevertheless our PPR values for benzene were more reliable at lower flow rates (0.75-1.20%). This study highlights the importance of flow rate and associated pressure changes as a key to accurate permeation rate estimation from permeation tube devices.

Affiliation

Department of Environment & Energy, Sejong University, 98 Goon Ja Dong, Seoul 143-747, South Korea.

Journal Details

This article was published in the following journal.

Name: Journal of chromatography. A
ISSN: 1873-3778
Pages: 9328-35

Links

DeepDyve research library

PubMed Articles [18075 Associated PubMed Articles listed on BioPortfolio]

SAMPA: A free software tool for skin and membrane permeation data analysis.

Skin and membrane permeation experiments comprise an important step in the development of a transdermal or topical formulation or toxicological risk assessment. The standard method for analyzing these...

Transdermal delivery of cimetidine across microneedle-treated skin: Effect of extent of drug ionization on the permeation.

The objective of this work was to optimize a gel formulation of cimetidine to maximize its transdermal delivery across microporated skin. Specifically, the effect of extent of ionization in formulatio...

Membrane Permeation versus Amyloidogenicity: A Multitechnique Study of Islet Amyloid Polypeptide Interaction with Model Membranes.

Islet amyloid polypeptide (IAPP) is responsible for cell depletion in the pancreatic islets of Langherans, and for multiple pathological consequences encountered by patients suffering from type 2 Diab...

Expanding transdermal delivery with lipid nanoparticles: a new drug-in-NLC-in-adhesive design.

A monolithic drug-in-NLC-in-adhesive transdermal patch, with a novel design, was developed for co-delivery of olanzapine (OL) and simvastatin (SV). Nanostructured lipid carriers (NLC) and enhancers we...

Development and characterization of polymer-coated liposomes for vaginal delivery of sildenafil citrate.

Vaginal administration of sildenafil citrate has shown recently to develop efficiently the uterine lining with subsequent successful embryo implantation following in vitro fertilization. The aim of th...

Clinical Trials [5954 Associated Clinical Trials listed on BioPortfolio]

Effect of Cobicistat Versus Ritonavir Boosting on the Brain Permeation of Darunavir in HIV-infected Individuals

The purpose of this study is to assess whether a boosting by cobicistat results in similar concentrations of darunavir in the brain compared to a boosting by ritonavir.

Fiber Formula Study Among Radiation Oncology Patients

During radiation treatment for head and neck cancer a large percentage of patients at Mayo Clinic Rochester develop the need for tube feeding to meet nutrition and hydration needs. These p...

Ultrasonography vs Cole Formula to Predict Endotracheal Tube Diameter

This study aims to compare the accuracy of measurement between ultrasonography and Cole formula in predicting uncuffed endotracheal tube diameter.

Enteral Formula Tolerance in Pediatric Patients

The purpose of this prospective observational study seeks to assess ability to achieve enteral feeding goals with standard polymeric enteral formula in a stable, pediatric tube-fed populat...

Improvement Project To Optimizing Nutrition With Higher Protein and Calorie Pediatric Tube Feeding

This quality improvement project will include a practice change based on national guidelines for the nutritional management of PICU patients.

Medical and Biotech [MESH] Definitions

The transparent anterior portion of the fibrous coat of the eye consisting of five layers: stratified squamous CORNEAL EPITHELIUM; BOWMAN MEMBRANE; CORNEAL STROMA; DESCEMET MEMBRANE; and mesenchymal CORNEAL ENDOTHELIUM. It serves as the first refracting medium of the eye. It is structurally continuous with the SCLERA, avascular, receiving its nourishment by permeation through spaces between the lamellae, and is innervated by the ophthalmic division of the TRIGEMINAL NERVE via the ciliary nerves and those of the surrounding conjunctiva which together form plexuses. (Cline et al., Dictionary of Visual Science, 4th ed)

A very complex, but reproducible mixture of at least 177 C10 polychloro derivatives, having an approximate overall empirical formula of C10-H10-Cl8. It is used as an insecticide and may reasonably be anticipated to be a carcinogen: Fourth Annual Report on Carcinogens (NTP 85-002, 1985). (From Merck Index, 11th ed)

The removal of secretions, gas or fluid from hollow or tubular organs or cavities by means of a tube and a device that acts on negative pressure.

Removal of a MEDICAL DEVICE from the market due to the identification of an intrinsic property of the device that results in a serious risk to public health.

The two longitudinal ridges along the PRIMITIVE STREAK appearing near the end of GASTRULATION during development of nervous system (NEURULATION). The ridges are formed by folding of NEURAL PLATE. Between the ridges is a neural groove which deepens as the fold become elevated. When the folds meet at midline, the groove becomes a closed tube, the NEURAL TUBE.

Quick Search
Advertisement
 


DeepDyve research library

Searches Linking to this Article