• Archives of Pharmacal Research
• /
• 제19권2호
• /
• pp.100-105
• /
• 1996

Polyethylene glycols (PEGs; 400, 600, and 1000) were used to study the molecular weight (MW) permeability dependence in the rat ileal mucosa. Absorption of the PEGs was measured by following their recirculation perfusion over a 3 hr collection period. HPLC methods were used to separate and quantitate the individual oligomers present in the solution of PEGs mixtures (MW range 330 to 1 1 22 D). In the range studied, a distinct molecular weight cutoff was not identified. Corrected for the length of ileum used in the study, over the molecular weight range 330 to 1122 D, the apparent permeability $(P_{app)$ of PEG ranged from $3.2\pm0.06\times10_{-5} cm/sec(mean\pmSEM, n=7)\; to\; 0.1\pm0.02\times10^{-5} cm/sec.$ Also, it was observed that the apparent permeability was inversely proportional to approximately $MW^{2.4}$.

• Journal of Nutrition and Health
• /
• 제29권2호
• /
• pp.153-158
• /
• 1996

Polyethylene glycols(PEGs)are hydrophilic molecules that have been used to characterize intestinal permeability via the paracellular pathway. Using a mixture of PEGs(400, 600 and 1000), containing oligomers in the molecular weight range 330 to 1122 D, the molecular weight permeability dependence in the jejunum of the rat small intestine was examined, employing an in situ recirculation perfusion technique. Individual oligomers were determined by HPLC with refractive detection. In the range studied, a distinct molecular weight cut-off was not apparent. Corrected for the length of jejunum used in the study, over the molecular weight range 330 to 1122D, the apparent permeability(Papp) of PEG ranged from 4.92$\pm$0.02$\times$10-5cm/sec(mean$\pm$SEM, n=5) to 0.28$\times$10-5cm/sec. Also, it was observed that the apparent permeability was inversely proportional to approximately MW2. The results in this study suggest that molecular weight is an important factor in determining the intestinal permeability.

• Archives of Pharmacal Research
• /
• 제7권1호
• /
• pp.1-9
• /
• 1984

Polyethylene glycol 20, 000 and 6, 000 were found to have an upper consolute temperature, called "cloud point", and the effects of various additives on the polythylene glycols were investigated in this study. Electrolytes lowered the cloud point in proportion to their concentrations through dehydration and electrostriction. It was found that anions played a more important role than cations and the effects of both the cations and the anions clearly followed the classical Hofmeister series. However, the Schultze Hardy rule holds for the effect of anions, and fails for the effect of cations. Salts of large polarizable anions such as iodide and thiocynate rather raised the cloud point, and their effects were ascribed to the fact that they break the water structure and weaken hydrophobic bonding of the polyxyethylene moiety. Nitrates of polyvalent cations also raised the cloud point. This was ascribed to the complex formation between the polyvalent cations and ether oxygens of the polyoxyethylenes. This explained the failure 'of the Schultz-Hardy rule for cations. Uncharged aromatic compounds drastically lowered the clound point, while aliphatic alcohols slightly lowered the cloud point, This result suggests that there might be some interaction between ether oxygens and aromatic nucleus.c nucleus.

• Mass Spectrometry Letters
• /
• 제5권2호
• /
• pp.49-51
• /
• 2014

The effectiveness of tertiary matrices composed of the combination of three common matrices (dihydrobenzoic acid (DHB), ${\alpha}$-cyano-4-hydroxycinnamic acid (CHCA), and sinapinic acid (SA)) was compared with that of single or binary matrices in the analysis of polyethylene glycol (PEG) polymers ranging from 1400 to 10000 Da using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). A tertiary matrix of 2,5-DHB+CHCA+SA was the most effective in terms of S/N ratios. CHCA and CHCA+SA produced the highest S/N ratios among the single matrices and the binary matrices, respectively. The improvement observed when using a tertiary matrix in analyses of PEG polymers by MALDI-TOF MS is believed to be due to the uniform morphology of the MALDI sample spots and synergistic effects arising from the mixture of the three matrix materials.

• 한국물환경학회지
• /
• 제25권4호
• /
• pp.502-506
• /
• 2009

The removal properties of Polyethylene glycols (PEGs) known as the important group of synthetic polymers of ethylene oxide were examined by the bio-reactor equipped with a mesh filter module. PEG-1000 and PEG-2000 were fairly removed on the basis of TOC, which were 75.1% and 51.6%, respectively. In the case of PEG-20000, the removal efficiency of TOC was less than 15.2% and the favorable acclimation of microbes was not obtained. It was suggested that this system could effectively maintain microbes for the biodegradation of low molecular weight of PEG and TOC removal was significantly influenced by PEG molecular weight.

• Mass Spectrometry Letters
• /
• 제1권1호
• /
• pp.33-36
• /
• 2010

Wood charcoal was investigated to determine its potential as an alternative matrix for matrix-assisted laser desorption/ionization of various samples. Wood charcoal was an effective matrix for analyzing glucose, sucrose, arginine, and polyethylene glycols (PEGs), with detection levels of 100 pmol for glucose, 1 nmol for sucrose, 100 pmol for arginine, 100 pmol for PEG 400, 1 pmol for PEG 1540, and 10 pmol for PEG 3350. No analyte signal was observed for peptides or proteins.

• 대한약학회:학술대회논문집
• /
• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
• /
• pp.233.3-234
• /
• 2003

Electroosmotic flux during iontophoresis originates due to the net negative charge of the current passing channel (pores) in skin at physiological pH (pH 7.4). Thus, the channel is permselective to cations, and this causes the convective solvent flow, from anode to cathode direction. This solvent flow facilitates the flux of cations (from anode), inhibits that of anions (from cathode), and enables the enhanced transport of neutral, polar solutes. In this work, we have investigated the effect of a series of polyethylene glycols (PEGs) with different molecular weights on the electroosmtic flow to get more detail understanding of this phenomena. (omitted)

• Toxicological Research
• /
• 제31권2호
• /
• pp.105-136
• /
• 2015

Polyethylene glycols (PEGs) are products of condensed ethylene oxide and water that can have various derivatives and functions. Since many PEG types are hydrophilic, they are favorably used as penetration enhancers, especially in topical dermatological preparations. PEGs, together with their typically nonionic derivatives, are broadly utilized in cosmetic products as surfactants, emulsifiers, cleansing agents, humectants, and skin conditioners. The compounds studied in this review include PEG/PPG-17/6 copolymer, PEG-20 glyceryl triisostearate, PEG-40 hydrogenated castor oil, and PEG-60 hydrogenated castor oil. Overall, much of the data available in this review are on PEGylated oils (PEG-40 and PEG-60 hydrogenated castor oils), which were recommended as safe for use in cosmetics up to 100% concentration. Currently, PEG-20 glyceryl triisostearate and PEGylated oils are considered safe for cosmetic use according to the results of relevant studies. Additionally, PEG/PPG-17/6 copolymer should be further studied to ensure its safety as a cosmetic ingredient.

• Bulletin of the Korean Chemical Society
• /
• 제30권5호
• /
• pp.1127-1130
• /
• 2009

The effects of different dihydroxybenzoic acid (DHB) isomers, when used as matrix materials in matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS), were investigated in analyses of polyethylene glycol (PEG) polymers. PEG polymers ranging from 400 to 8,000 Da were prepared in different DHB isomer matrices using solvent-based and solvent-free methods. PEG samples were detected only in matrices of 2,3-DHB, 2,5-DHB, and 2,6-DHB while the most intense peaks were observed using 2,6-DHB in both solvent-free and solvent-based preparations.

• 통합자연과학논문집
• /
• 제13권2호
• /
• pp.41-46
• /
• 2020

A study is reported about the synthesis processes of various silacrown ether by the reaction of alkoxysilanes with polyethylene glycols (PEG) through transesterification. Crown ether-functionalized carbosilane dendrimers and hybrid crown ethers are also discussed. We will also address the solubility enhancement, phase-transfer catalysis of different silacrown as well as their application as Ion-selective electrodes (ISEs) and as active phase of PVC electrodes for the development of potentiometric sensors for detection of alkali-Ions.