surfactants polymers and phospholipids

... hydrophilic, (poly vinyl alcohol, PVA, and randomly methylated βcyclodextrin, RM β-CD), and hydrophobic (poly d,l-lactide, PLA, and poly d,llactide-co-glycolide, PLGA) polymers were electrospun to make ... Polyesters, PLA and PLGA, releases drug via hydrolysis of the polymer and could provide sustained and controlled release rate of the drug Blends of these hydrophilic and hydrophobic polymers could ... surfactant, Spans and Tweens, were studied The effect of hydrophilic-lipophilic balance (HLB value) of one or two surfactants on drug solubility, proniosome surface structure and stability and skin permeation...

Ngày tải lên: 14/09/2015, 14:03

... potential of polymers and phospholipids for improving the topical and transdermal delivery of therapeutic agents and cosmetic ingredients is worth exploring Factors that influence transdermal and topical ... (Karande and Mitragotri 2002; Karande et al., 2007 and 2006; Whitehead et al., 2008) In this work the concentration of the two surfactants were calculated to obtain the required HLB value and ... the keratinocytes and (3) transappendageal permeation through the sweat glands and across the hair follicles (Godin and Touitou 2007; El Maghraby et al., 2008) 1.2 Topical and Transdermal Drug...

Ngày tải lên: 14/09/2015, 14:03

... (PLA) and its copolymers with glycolic acid (PLGA) are remarkable for sustained drug delivery and targeting drugs to specific sites PLA and PLGA are biocompatible and biodegradable polymers, and ... PLA and PLGA and the multilayered fiber mats (Fig 4.3) From the FTIR spectra of PLA and PLGA 48:52 and 73:27 it was observed that the C=O and C-O-C stretching peaks were detected at 1747 and ... adjusting the pH and concentration of RM β-CD to obtain improved solubility and therefore skin permeability of the drug (Sridevi and Diwan 2002 a and b; Singh et al., 2005) Both ionized and unionized...

Ngày tải lên: 14/09/2015, 14:03

... spectrophotometer, Hitachi, Japan) at 261 and 349 nm for AA and RA respectively Standard solutions of AA and RA (0.05 to 2.00 μg/ml) were prepared in water and water ethanol solutions respectively ... formaldehyde and ml acetic acid (Gaspar and Campos 2007) After a series of dehydration, they were embedded in paraffin and semi-thin sections were cut and stained with hematoxylin and eosin prior ... Results and Discussion 6.3.1 FTIR Measurements of the Drug-Loaded Nanofibers The interactions between the polymers and T4 were analyzed by FTIR (Fig 6.1) For pure PVA (Fig 6.1a), a broad band around...

Ngày tải lên: 14/09/2015, 14:03

... 2007; Hua and Liu et al., 2007) and other formulations such as proniosomes, containing cholesterol and non-ionic surfactants, were developed (Alsarra et al., 2005; Fang et al., 2001; Hu and Rhodes ... effect between the [CD] and skin permeation - Continious and controlled release of haloperidol can be achieved with blends of hydrophilic and hydrophobic polymers PNIPAM and PVA nanofiber Topical ... the epidermis and decrease the drug permeation through the skin (Ga de Jalón et al., 2001a and b; Rolland et al., 1993; Tsujimoto et al., 2007) Several studies have shown sustained and controlled...

Ngày tải lên: 14/09/2015, 14:03

... Branched polymers and dimensional reduction By David C Brydges and John Z Imbrie* Abstract We establish an exact relation between self-avoiding branched polymers in D + continuum dimensions and the ... self-avoiding loops and vesicles [Car01] depend on a reduction of branched polymers to the zerodimensional iϕ3 theory BRANCHED POLYMERS AND DIMENSIONAL REDUCTION 1029 Our Theorems 1.1 and 1.3 provide ... configurations available to dimers and trimers is indeed π, 4π /3, respectively, in d = and 2π, 6π , respectively, in d = For larger values of N , BRANCHED POLYMERS AND DIMENSIONAL REDUCTION 1023...

Ngày tải lên: 05/03/2014, 23:20

... increased mobility and the smeared bands resolved into a single defined band (data not shown) Variant forms of sEPCR were generated by site-directed mutagenesis (N30Q, L37A and E86A) and were expressed, ... phosphatidylcholine and phosphatidylserine (90 : 10, v ⁄ v) and 0.08 nM APC in 40 mM Tris ⁄ HCl, 140 mM NaCl, mM CaCl2 and 0.3% (w ⁄ v) BSA at 37 °C Aliquots (2 lL) were removed and added to 75 lM phospholipids ... at 37 °C, and lL aliquots removed and added to a prothrombinase mixture, consisting of 75 lm phospholipids (phosphatidylcholine and phosphatidylserine; 90 : 10, v ⁄ v), nm factor Xa and 1.5 lm...

Ngày tải lên: 16/03/2014, 18:20

... properties of polymers and composites / Lawrence E Nielsen Robert F Landel — 2nd ed., rev and expanded p cm — (Mechanical engineering ; 90) Includes bibliographical references and index ISBN ... Common Polymers Conversion Factors for Moduli, Stress, and Viscosity Glass Transition Temperatures and Melting Points of Polymers Relations Between Engineering Moduli and Tensor Moduli and Tensor ... and folding which are possible within and between lamellae and between ribbon surfaces In real, well-crystallized polymers, these variations he relatively far apart and the forms SC" CF, SB and...

Ngày tải lên: 22/03/2014, 12:20

... properties of polymers and composites / Lawrence E Nielsen Robert F Landel — 2nd ed., rev and expanded p cm — (Mechanical engineering ; 90) Includes bibliographical references and index ISBN ... Common Polymers Conversion Factors for Moduli, Stress, and Viscosity Glass Transition Temperatures and Melting Points of Polymers Relations Between Engineering Moduli and Tensor Moduli and Tensor ... and folding which are possible within and between lamellae and between ribbon surfaces In real, well-crystallized polymers, these variations he relatively far apart and the forms SC" CF, SB and...

Ngày tải lên: 22/03/2014, 13:20

... fluorinated fluorocarbon polymers such as PTFE, FEP, and PPA called perfluoropolymers, and the partially fluorinated polymers such as ETFE, PVDF, and ECTFE that are called fluoropolymers The polymeric ... Thermoplastic polymers can be either homopolymers or copolymers Alloy polymers are blends of different polymers In general, thermoplastic materials tend to be tougher and less brittle than thermoset polymers, ... metals and ceramics.” Others have limited the term to thermoplastics only Many engineering polymers are reinforced and/ or alloy polymers (a blend of polymers) Polyethylene, polypropylene, PVC, and...

Ngày tải lên: 02/04/2014, 16:27

... fluorinated fluorocarbon polymers such as PTFE, FEP, and PPA called perfluoropolymers, and the partially fluorinated polymers such as ETFE, PVDF, and ECTFE that are called fluoropolymers The polymeric ... Thermoplastic polymers can be either homopolymers or copolymers Alloy polymers are blends of different polymers In general, thermoplastic materials tend to be tougher and less brittle than thermoset polymers, ... metals and ceramics.” Others have limited the term to thermoplastics only Many engineering polymers are reinforced and/ or alloy polymers (a blend of polymers) Polyethylene, polypropylene, PVC, and...

Ngày tải lên: 02/04/2014, 16:27

... pulp and metalized inhouse The film is printable with solvent and with water-based and UV inks and has an excellent luster and sheen for pack presentation NatureFlex NM builds on the longstanding ... 17 Chandra, R and Rustgi, R (1998) Biodegradable polymers Progress in Polymer Science, 23, 1273 18 Chandy, T and Sharma, C.P (1990) Chitosan – as a biomaterial Biomaterials Artificial Cells and ... natural gas, and polypropylene (PP), which is derived from crude oil All these polymers are used to make a variety of 15 16 Biodegradable Polymers and Their Practical Utility containers and films...

Ngày tải lên: 22/04/2014, 22:38

... polyethylene and ethylene copolymers and derivatives; (B) polypropylene and propylene copolymers and derivatives; and (C) polymers and copolymers based on other 1-olefins Many of these polymers, ... blocky: I.T alternating: I.U or random: I.V or a second chain can be grafted onto the first: I.W Blocky and random copolymers are the most common In block copolymers, the length of the block ... 1983 27 E T Hsieh and J C Randall Macromolecules 15:353, 1982 28 E T Hsieh and J C Randall Macromolecules 15:1402, 1982 29 H N Cheng Polym Commune 25:99, 1984 30 K Kimura, S Yuasa, and Y Maru Polyemr...

Ngày tải lên: 01/06/2014, 10:11

... wrote: They take the wood and make slices of it as thin as possible, and not very large, and place them in clear spring water, that must be very good and transparent, and they leave them all the ... imaging and uorescent probes are indispensible tools in numerous elds of modern medicine and science, including molecular biology, biophysics, biochemistry, clinical diagnosis and analytical and ... stretch from spectroscopy and sensor technology to microscopy and imaging, to single molecule detection, to the development of novel uorescent probes, and to proteomics and genomics The Springer...

Ngày tải lên: 04/06/2014, 14:35

... properties of polymers and composites / Lawrence E Nielsen Robert F Landel — 2nd ed., rev and expanded p cm — (Mechanical engineering ; 90) Includes bibliographical references and index ISBN ... Common Polymers Conversion Factors for Moduli, Stress, and Viscosity Glass Transition Temperatures and Melting Points of Polymers Relations Between Engineering Moduli and Tensor Moduli and Tensor ... and folding which are possible within and between lamellae and between ribbon surfaces In real, well-crystallized polymers, these variations he relatively far apart and the forms SC" CF, SB and...

Ngày tải lên: 26/06/2014, 23:20

... properties of green polymers such as natural polymers and polymers derived from saccharides and lignins The above green polymers include polymers such as poly(ε-caprolactone) (PCL) and polyurethane ... lignin and green polymers by thermal and mechanical analyses, spectroscopy, and x-ray diffractometry Synthesis of green polymers derived from saccharides and lignins, such as polyurethane and polycaprolactone ... SYNTHETIC GREEN POLYMERS: MOLASSES AND LIGNIN 3.1 Molasses Molasses is a brown viscous liquid and is produced from sugar cane and beet The chemical components of molasses consist of sucrose and saccharides...

Ngày tải lên: 27/06/2014, 15:20

... properties of polymers and composites / Lawrence E Nielsen Robert F Landel — 2nd ed., rev and expanded p cm — (Mechanical engineering ; 90) Includes bibliographical references and index ISBN ... Common Polymers Conversion Factors for Moduli, Stress, and Viscosity Glass Transition Temperatures and Melting Points of Polymers Relations Between Engineering Moduli and Tensor Moduli and Tensor ... and folding which are possible within and between lamellae and between ribbon surfaces In real, well-crystallized polymers, these variations he relatively far apart and the forms SC" CF, SB and...

Ngày tải lên: 27/06/2014, 17:20

... dominance in packaging and building and construction markets However, engineering thermoset and thermoplastic polymers also offer outstanding performance in certain demanding Babinec and Cornell FIG ... Coatings of Polymers and Plastics, edited by Rose A Ryntz and Philip V Yaneff Additional Volumes in Preparation Micromechatronics, Kenji Uchino andJayne Giniewicz Ceramic Processing and Sintering: ... formability, and low cost While new types and grades of plastics emerge, many new and exciting challenges are introduced for the coating formulator and, ultimately, the part decorator Adhesion and painted-part...

Ngày tải lên: 10/08/2014, 11:21

... Comprehensive experimental and theoretical treatments describe and predict the shape of the percolation curve and the basic behaviors of composites as a function of both conductive filler and the host polymer ... Introduction to Soft Matter, Polymers, Colloids, Amphiphiles, and Liquid Crystals New York: Wiley, 2000 RJ Young, PA Lovell Introduction to Polymers, 2nd ed London: Chapman and Hall, 1991, ch MF Ashby ... charges and preforms The first and most common approach is to open the mold and introduce a preweighed charge of solid material into the lower half of the mold The mold is then closed and the...

Ngày tải lên: 10/08/2014, 11:21

... understanding, and a working model to explain the results and build on them to achieve a final objective of a useful, commercial material 92 Berta STRENGTH OF BONDS Physical Bonds a Random dipole-induced ... (23,24) By and large, adhesion is addressed with various paints and curing conditions, and various tapes are used to the testing In most cases, multiple pulls were not addressed, and the durability ... were made and tested for paint adhesion and durability with acceptable results (R.A Ryntz, private communication) 5.5 Paint Type and Curing Paint systems differ in their cure chemistry and ingredient...

Ngày tải lên: 10/08/2014, 11:21