Abstract：
:The aim of this work was to study the effect of the type of substituent of the cellulose ethers and the molecular mass on the state and dynamics of water in the respective hydrogels to specify the quantity of adsorbed water on the polymers or, more explicitly, to calculate the average number of water molecules bound to a polymer repeating unit (PRU). 1H NMR relaxation experiments were performed on equilibrated systems of cellulose ether polymers (HEC, HPC, HPMC K4M, and HPMC K100M) with water. In particular, the water proton spin-lattice (T1) and spin-spin (T2) relaxation times were measured in these systems at room temperature. The observed proton NMR T1 and T2 of water in hydrogels at different cellulose ether concentrations at room temperature were shown to decrease with increasing polymer concentration. The relaxation rate 1/T1 is sensitive to the type of polymer substituent but insensitive to the polymer molecular mass. The rate 1/T2 appears much less influenced by the polymer substitution. The procedure developed for calculating the amount of water bound per PRU, based on the analysis of the T1 and T2 data, shows that this amount is the largest for HPC followed by HEC, HPMC K4M, and HPMC K100M. The results correlate well with the degree of hydrophilic substitution of the polymer chains. This NMR analysis deals with a single molecular layer of adsorbed water for the investigated cellulose ether polymers at all concentrations, while the rest of the water in the hydrogel is bulk-like. Therefore, the mesh size of polymer network in the view of a single molecular layer is not effectively changed.
journal_name
AAPS PharmSciTechjournal_title
AAPS PharmSciTechauthors
Baumgartner S,Lahajnar G,Sepe A,Kristl Jdoi
10.1208/pt030436keywords:
subject
Has Abstractpub_date
2002-01-01 00:00:00pages
E36issue
4issn
1530-9932journal_volume
3pub_type
杂志文章abstract：:A new, simple, inexpensive, and rapid 96-well plate UV spectrophotometric method was developed and validated for the quantification of compound 48/80 (C48/80) associated with particles. C48/80 was quantified at 570 nm after reaction with acetaldehyde and sodium nitroprusside in an alkaline solution (pH 9.6). The metho...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/s12249-013-9950-4
更新日期：2013-06-01 00:00:00
abstract：:The effects of electron beam or gamma-irradiation on technological performances (capsule hardness, expressed as deforming work and dissolution time) of empty 2-shell capsules made of gelatin or hydroxypropylmethylcellulose (HPMC) were studied. Capsule structural changes induced by radiation treatment were investigated...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/pt060473
更新日期：2005-12-01 00:00:00
abstract：:AR-12 is a novel small molecule with broad spectrum antifungal activity. Recently, AR-12 was found to be highly active against Trichophyton rubrum, one of the predominantly responsible organisms that cause onychomycosis. The primary objective of this project was to investigate the ability of AR-12 to penetrate into an...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/s12249-017-0752-y
更新日期：2017-10-01 00:00:00
abstract：:Vemurafenib is a poorly soluble, low permeability drug that has a demonstrated need for a solubility-enhanced formulation. However, conventional approaches for amorphous solid dispersion production are challenging due to the physiochemical properties of the compound. A suitable and novel method for creating an amorpho...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/s12249-018-0988-1
更新日期：2018-07-01 00:00:00
abstract：:The purpose of this research was to explore the utility of beta cyclodextrin (betaCD) and beta cyclodextrin derivatives (hydroxypropyl-beta-cyclodextrin [HPbetaCD], sulfobutylether-beta-CD [SBbetaCD], and a randomly methylated-beta-CD [RMbetaCD]) to form inclusion complexes with the antitumoral drug, beta-lapachone (b...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/pt0803060
更新日期：2007-07-27 00:00:00
abstract：:A transdermal drug delivery system (TDDS) is generally designed to deliver an active pharmaceutical ingredient (API) through the skin for systemic action. Permeation of an API through the skin is controlled by adjusting drug concentration, formulation composition, and patch design. A bilayer, drug-in-adhesive TDDS des...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/s12249-020-01682-4
更新日期：2020-06-04 00:00:00
abstract：:The present study demonstrates a preparative medium-pressure liquid chromatography (MPLC) method for isolation of Morin besides evaluating its efficacy in comparison with its self-nanoemulsifying drug delivery (SNEDD) and nanoemulsion (NE) systems against in-vivo HgCl2-induced lung toxicity in rats. Morin was isolated...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/s12249-018-1072-6
更新日期：2018-07-01 00:00:00
abstract：:The ability to produce submicron particles of monoclonal antibodies of different sizes and shapes would enhance their application to pulmonary delivery. Although non-ionic surfactants are widely used as stabilizers in protein formulations, we hypothesized that non-ionic surfactants will affect the shape and size of su...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/s12249-012-9913-1
更新日期：2013-03-01 00:00:00
abstract：:Topical administration is a preferable choice for local anesthetic delivery. Microemulsions have shown great effectiveness for transdermal transport of lidocaine. However, fabrication of microemulsions containing highly concentrated lidocaine (10%) to provide an extended local anesthetic effect is still a challenge. T...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/s12249-018-1263-1
更新日期：2019-01-09 00:00:00
abstract：:The purpose of this study was to develop formulations and systematically evaluate in vitro performances of buccoadhesive patches of propranolol hydrochloride using the hydrophobic polymer Eudragit L-100 as the base matrix. The hydrophilic polymers Carbopol 934 and polyvinyl pyrrolidone (PVP) K30 were incorporated into...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/pt0802045
更新日期：2007-06-22 00:00:00
abstract：:To enhance the stability of coenzyme Q10 (CoQ10), Kolliphor® HS 15 (HS15) was employed as a carrier to build up a stable CoQ10-loaded micelle delivery system. The impact of micellar compositions, the preparation condition, and the preparation method on size characteristics, the solubilization efficiency, and micellar ...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/s12249-015-0399-5
更新日期：2016-06-01 00:00:00
abstract：:Particulate drug delivery systems (PDDS) have been broadly explored as platforms for delivery of drugs, enzymes, cells, and vaccines for pharmaceutical applications. Studies suggest that microspheres (MS) can stimulate innate immune cells even without a drug payload; however, less is known regarding how they impact ho...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/s12249-019-1458-0
更新日期：2019-06-27 00:00:00
abstract：:The performance of dioctyl sodium sulfosuccinate (aerosol OT) in the development of a pharmaceutically acceptable, stable, self-emulsifying water continuous microemulsion with high dilution efficiency was assessed. A pseudoternary microemulsion system was constructed using aerosol OT/medium-chain triglycerides with ol...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/pt040111
更新日期：2003-01-01 00:00:00
abstract：:This investigation was undertaken to evaluate practical feasibility of site specific pulmonary delivery of liposomal encapsulated Dapsone (DS) dry powder inhaler for prolonged drug retention in lungs as an effective alternative in prevention of Pneumocystis carinii pneumonia (PCP) associated with immunocompromised pat...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/s12249-007-9024-6
更新日期：2008-01-01 00:00:00
abstract：:Pharmaceutical aerosols have been targeted to the lungs for the treatment of asthma and pulmonary infectious diseases successfully. Micafungin (Astellas Pharma US, Deerfield, IL, USA) has been shown to be an effective antifungal agent when administrated intravenously. Pulmonary delivery of micafungin has not previousl...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/s12249-009-9185-6
更新日期：2009-01-01 00:00:00
abstract：:Gliclazide (GLI), a poorly water-soluble antidiabetic, was transformed into a glassy state by melt quench technique in order to improve its physicochemical properties. Chemical stability of GLI during formation of glass was assessed by monitoring thin-layer chromatography, and an existence of amorphous form was confir...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/s12249-012-9760-0
更新日期：2012-06-01 00:00:00
abstract：:The aim of this work was to test innovative approach for enhancing ascorbyl palmitate stability in microemulsions for topical application by addition of newly synthesized co-antioxidant 4-(tridecyloxy)benzaldehyde oxime (TDBO) and to investigate its antioxidant activity and finally to evaluate cytotoxicity of TDBO-loa...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/s12249-010-9507-8
更新日期：2010-09-01 00:00:00
abstract：:A number of synthesized chemical molecules suffer from low aqueous solubility problems. Enhancement of aqueous solubility, dissolution rate, and bioavailability of drug is a very challenging task in drug development. In the present study, solubility and dissolution of poorly aqueous soluble drug simvastatin (SIM) was ...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/s12249-008-9176-z
更新日期：2008-01-01 00:00:00
abstract：:The use of amorphous solid dispersions to improve the bioavailability of active ingredients from the BCS II and IV classifications continues to gain interest in the pharmaceutical industry. Over the last decade, methods for generating amorphous solid dispersions have been well established in commercially available pro...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章,评审
doi：10.1208/s12249-017-0861-7
更新日期：2018-07-01 00:00:00
abstract：:This study examined the effect of rotor speed, amount of water sprayed, and atomizing air pressure on the geometric mean diameter and geometric standard deviation of pellets produced in a fluid-bed rotor granulator using a 23 factorial design and an optimization technique. Pellets were prepared by wet granulation. Equ...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/pt010435
更新日期：2000-12-01 00:00:00
abstract：:The purpose of this research was to evaluate in vitro transnasal sustained-release ability of sorbitan monostearate (SMS) organogels in isopropyl myristate (IM). Organogels were prepared containing SMS (2.5%-20%) and water (5%-25%) in IM and analyzed microscopically for phase behavior. The effect of Tween surfactants ...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/pt050463
更新日期：2004-09-13 00:00:00
abstract：:Nanoparticles fabricated from the biodegradable and biocompatible polymer, polylactic-co-glycolic acid (PLGA), could be a promising system for targeting ocular drug delivery. The objective of this work was to investigate the possibility of encapsulating brinzolamide in PLGA nanoparticles in order to be applied as a su...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/s12249-017-0710-8
更新日期：2017-10-01 00:00:00
abstract：:Rheumatoid arthritis is an autoimmune disease that leads to cartilage destruction, synovial joint inflammation, and bacterial joint/bone infections. In the present work, methotrexate and minocycline-loaded nanoparticles (MMNPs) were developed with an aim to provide relief from inflammation and disease progression/join...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/s12249-019-1581-y
更新日期：2019-12-23 00:00:00
abstract：:Colorectal cancer (CRC) is the third most common cancer worldwide. Its poor response to current treatment options in advanced stages and the need for efficient diagnosis in early stages call for the development of new therapeutic and diagnostic strategies. Some of them are based on the use of nanometric materials as c...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章,评审
doi：10.1208/s12249-020-01731-y
更新日期：2020-06-26 00:00:00
abstract：:Combined dissolution and permeation systems are designed to simultaneously assess the dissolution of a pharmaceutical dosage form and the permeation of dissolved drugs therefrom. However, there were still some limitations on predicting the possible absorption rate-limiting steps and improving the in vitro-in vivo corr...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/s12249-019-1544-3
更新日期：2019-10-24 00:00:00
abstract：:We have designed a microemulsion (ME) containing Ketoprofen (KET) for anti-inflammatory effect evaluated using the rat paw edema model. The ME was prepared by adding propylene glycol (PG) loaded with 1% KET/water (3:1, w/w), to a mixture of sorbitan monooleate and polysorbate 80 (47.0%) at 3:1 (w/w) and canola oil (38...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/s12249-017-0749-6
更新日期：2017-10-01 00:00:00
abstract：:MUC1 gene encodes a transmembrane mucin glycoprotein that is overexpressed in human breast cancer and colon cancer. The objective of this study was to develop an in situ gel delivery system containing paclitaxel (PTX) and mucoadhesives for sustained and targeted delivery of anticancer drugs. The delivery system consis...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/pt070253
更新日期：2006-06-02 00:00:00
abstract：:The aim of this study was to develop benzydamine hydrochloride-loaded orodispersible films using the modification of a solvent casting method. An innovative approach was developed when the drying process of a small-scale production was used based on a heated inert base for casting the film. During this process, two ty...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/s12249-018-1088-y
更新日期：2018-08-01 00:00:00
abstract：:The purpose of the present study was to design mucoadhesive gliadin nanoparticles (GNP) containing amoxicillin and to evaluate their effectiveness in eradicating Helicobacter pylori. GNP-bearing amoxicillin (AGNP) was prepared by desolvation method. The effect of process variables such as gliadin concentration and ini...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/pt050232
更新日期：2004-04-07 00:00:00
abstract：:A melt solidification technique has been developed to obtain sustained-release waxy beads of flurbiprofen. Low glass transition temperature (t(g)) and shear-induced crystallization of flurbiprofen made it a suitable candidate for melt solidification technique. The process involved emulsification and solidification of ...
journal_title：AAPS PharmSciTech
pub_type： 杂志文章
doi：10.1208/pt040465
更新日期：2003-12-16 00:00:00
