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A novel branched polyamine (polyethyleneimine, PEI) functionalized mesoporous silica (MS) adsorbent is developed via a facile "grafting-to" approach. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FT-IR) spectroscopy verified the effective surface functionalization of MS with monolayer and polymer. The transmission electron microscopy (TEM) was employed to reveal the morphology of the fabricated materials. The adsorption behavior of the polyamine functionalized mesoporous silica (MS-PEI) is assessed against anionic dyes. The adsorbent characteristics of MS-PEI are compared with a monolayer platform comprising of 3-aminopropyltriethoxy silane (APTES) functionalized mesoporous silica (MS-APTES). The adsorption behavior of the MS-PEI and MS-APTES toward anionic dyes is further evaluated by studying the effect of adsorbent dosage, pH, contact time, and temperature. Langmuir and Freundlich isotherm models are employed to understand the adsorption mechanism. The obtained kinetic data support a pseudo-second-order adsorption behavior for both monolayer and polymer functionalized MS. The associated thermodynamic parameters (Delta G degrees, Delta H degrees, and Delta S degrees) reveal that the process of adsorption with MS-PEI is more spontaneous and energetically favored as compared to the adsorption with MS-APTES. Taken together, the novel adsorbent system derived from a combination of MS and branched polymer (MS-PEI) shows the higher absorption efficiency and capacity toward the anionic dyes than the monolayer based adsorbent (MS-APTES)., Higher Education Commission (HEC) of PakistanHigher Education Commission of Pakistan [20-1799/RD/10-5302]; LUMS; Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [112M804], B.Y. acknowledges The Higher Education Commission (HEC) of Pakistan for Funding (Project No. 20-1799/R;D/10-5302) and LUMS for the Startup Grant. H.D. gratefully acknowledges The Scientific and Technological Research Council of Turkey (TUBITAK) for the financial support of Project No. 112M804.

Polyether ether ketone (PEEK) is a thermoplastic polymer of high technological relevance and is composed of repeating phenyl ether and benzophenone units. In the present work we will demonstrate the potential of UV irradiation assisted generation of free radicals on the surface benzophenone units to graft a variety of polymer chains on the PEEK surface. Both "grafting-to" and "grafting-from" approaches were explored by using different monomers and polymers. Styrene, butyl acrylate (BA), vinyl phosphonic acid (VPA), acrylic acid (AA), polyacrylic acid (PAA) and monomethoxy terminated oligo(ethylene glycol) methacrylate (MeOEGMA) were successfully utilized for this purpose. The functionalized membranes were characterized by X-ray photoelectron spectroscopy (XPS), attenuated total reflectance Fourier-transformed Infrared (ATR-FTIR) spectroscopy, atomic force microscopy (AFM), and contact angle (CA) goniometry. PAA and PVPA functionalized PEEK surfaces exhibited pH responsive wettability behavior. PAA functionalized PEEK surfaces were further modified with lysine, which led to the controlled surface wettability over a broader pH range as compared to the simple PAA functionalized surface. The grafting with polyMeOEGMA rendered PEEK surface with nonfouling properties against bacterial growth. Employing this highly economical and simple method, the surface properties of PEEK can be modulated and tuned according to a specific application. (C) 2014 Elsevier B.V. All rights reserved., Higher Education Commission (HEC) of PakistanHigher Education Commission of Pakistan [20-1799/RD/10-5302, 20-1740/RD/10-3368]; LUMS; Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [112M804], B.Y. acknowledges The Higher Education Commission (HEC) of Pakistan for Funding (Project No. 20-1799/R;D/10-5302 and 20-1740/R;D/10-3368) and LUMS for the Startup Grant. H.D. gratefully acknowledges The Scientific and Technological Research Council of Turkey (TUBITAK) for the financial support of Project No. 112M804.

Polyether ether ketone (PEEK) is a thermoplastic polymer of high technological relevance and is composed of repeating phenyl ether and benzophenone units. In the present work we will demonstrate the potential of UV irradiation assisted generation of free radicals on the surface benzophenone units to graft a variety of polymer chains on the PEEK surface. Both "grafting-to" and "grafting-from" approaches were explored by using different monomers and polymers. Styrene, butyl acrylate (BA), vinyl phosphonic acid (VPA), acrylic acid (AA), polyacrylic acid (PAA) and monomethoxy terminated oligo(ethylene glycol) methacrylate (MeOEGMA) were successfully utilized for this purpose. The functionalized membranes were characterized by X-ray photoelectron spectroscopy (XPS), attenuated total reflectance Fourier-transformed Infrared (ATR-FTIR) spectroscopy, atomic force microscopy (AFM), and contact angle (CA) goniometry. PAA and PVPA functionalized PEEK surfaces exhibited pH responsive wettability behavior. PAA functionalized PEEK surfaces were further modified with lysine, which led to the controlled surface wettability over a broader pH range as compared to the simple PAA functionalized surface. The grafting with polyMeOEGMA rendered PEEK surface with nonfouling properties against bacterial growth. Employing this highly economical and simple method, the surface properties of PEEK can be modulated and tuned according to a specific application. (C) 2014 Elsevier B.V. All rights reserved., Higher Education Commission (HEC) of PakistanHigher Education Commission of Pakistan [20-1799/RD/10-5302, 20-1740/RD/10-3368]; LUMS; Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [112M804], B.Y. acknowledges The Higher Education Commission (HEC) of Pakistan for Funding (Project No. 20-1799/R;D/10-5302 and 20-1740/R;D/10-3368) and LUMS for the Startup Grant. H.D. gratefully acknowledges The Scientific and Technological Research Council of Turkey (TUBITAK) for the financial support of Project No. 112M804.

A novel branched polyamine (polyethyleneimine, PEI) functionalized mesoporous silica (MS) adsorbent is developed via a facile "grafting-to" approach. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FT-IR) spectroscopy verified the effective surface functionalization of MS with monolayer and polymer. The transmission electron microscopy (TEM) was employed to reveal the morphology of the fabricated materials. The adsorption behavior of the polyamine functionalized mesoporous silica (MS-PEI) is assessed against anionic dyes. The adsorbent characteristics of MS-PEI are compared with a monolayer platform comprising of 3-aminopropyltriethoxy silane (APTES) functionalized mesoporous silica (MS-APTES). The adsorption behavior of the MS-PEI and MS-APTES toward anionic dyes is further evaluated by studying the effect of adsorbent dosage, pH, contact time, and temperature. Langmuir and Freundlich isotherm models are employed to understand the adsorption mechanism. The obtained kinetic data support a pseudo-second-order adsorption behavior for both monolayer and polymer functionalized MS. The associated thermodynamic parameters (Delta G degrees, Delta H degrees, and Delta S degrees) reveal that the process of adsorption with MS-PEI is more spontaneous and energetically favored as compared to the adsorption with MS-APTES. Taken together, the novel adsorbent system derived from a combination of MS and branched polymer (MS-PEI) shows the higher absorption efficiency and capacity toward the anionic dyes than the monolayer based adsorbent (MS-APTES)., Higher Education Commission (HEC) of PakistanHigher Education Commission of Pakistan [20-1799/RD/10-5302]; LUMS; Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [112M804], B.Y. acknowledges The Higher Education Commission (HEC) of Pakistan for Funding (Project No. 20-1799/R;D/10-5302) and LUMS for the Startup Grant. H.D. gratefully acknowledges The Scientific and Technological Research Council of Turkey (TUBITAK) for the financial support of Project No. 112M804.

The toxic and non-biodegradable nature of organic dyes necessitates the design and synthesis of novel adsorbents for their effective removal from the environment. This study reports an effective remediation behavior of surface-functionalized silica gel against water-soluble cationic dyes (up to 98 % removal). Thiol groups were functionalized at the surface of silica gel (SiO2-SH). The surface-tethered -SH groups were further oxidized to sulfonic acid groups to generate the negatively charged moieties at the surface of silica gel (SiO2-SO3H). The morphology of the developed adsorbents and the surface modifications were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). Uptake study of three cationic dyes, namely, rhodamine B (Rh B), rhodamine 6G (Rh 6G), and crystal violet (CV) with SiO2-SH and SiO2-SO3H adsorbents was performed by varying the adsorbent amount, contact time, pH of solution, and temperature. The presence of negatively charged species at the surface of SiO2-SO3H results in an increased electrostatic interaction with the cationic dyes, which leads to better remediation characteristics for SiO2-SO3H as compared to SiO2-SH. The reusability of the developed adsorbents was also assessed by investigating adsorption/desorption of dyes. The simple fabrication process provides a facile avenue to the adsorbents with efficient remediation towards cationic dyes., Higher Education Commision (HEC) of Pakistan [20-1799/RD/10-5302]; LUMS, B.Y. acknowledges financial support from Higher Education Commision (HEC) of Pakistan (Project No. 20-1799/R;D/10-5302) and a start-up grant from LUMS. H.D. and B.Y. thank UNAM, Bilkent University for XPS, TEM, and SEM analyses.

In this study, novel smart drug release films were prepared by blending chitosan with polyethylene glycol methyl ether (PEGME), also named as methoxy polyethylene glycol (mPEG), for controlled drug release applications. The polymeric films were characterized by Fourier transform infra-red for functional groups analysis, scanning electron microscopy for morphology and X-ray photoelectron spectroscopy for chemical and surface analysis followed by mechanical and thermal analysis. The mechanical properties showed that with the addition of PEGME (40%), the tensile strength and elongation break were increased up to 34.14 MPa and 26.40%, respectively as compared to the controlled sample (without PEGME). The developed biodegradable films were tested for Metformin hydrogen chloride release ability at a particular rate in phosphate buffer saline solution at pH 7.4. The results showed that chitosan/PEGME blends could be employed for controlled drug release and other biomedical applications. (C) 2017 The Authors. Production and hosting by Elsevier B.V. on behalf of King Saud University.

In this study, novel smart drug release films were prepared by blending chitosan with polyethylene glycol methyl ether (PEGME), also named as methoxy polyethylene glycol (mPEG), for controlled drug release applications. The polymeric films were characterized by Fourier transform infra-red for functional groups analysis, scanning electron microscopy for morphology and X-ray photoelectron spectroscopy for chemical and surface analysis followed by mechanical and thermal analysis. The mechanical properties showed that with the addition of PEGME (40%), the tensile strength and elongation break were increased up to 34.14 MPa and 26.40%, respectively as compared to the controlled sample (without PEGME). The developed biodegradable films were tested for Metformin hydrogen chloride release ability at a particular rate in phosphate buffer saline solution at pH 7.4. The results showed that chitosan/PEGME blends could be employed for controlled drug release and other biomedical applications. (C) 2017 The Authors. Production and hosting by Elsevier B.V. on behalf of King Saud University.

Synthetic polypeptides are kind of polymers which have a significant role due to their close relation to proteins so as their ability to assemble hierarchically stable ordered conformations. Even though there are many applications of nano-sized polypeptides, there are few reports [1-4] which indicate diameter size dependence on their structural and dynamic behaviors. Since macromolecules in nanoporous alumina (AAO) might have different segmental dynamics compared to bulk, in this thesis, the structural properties and the segmental dynamics of poly (Z-L-lysine) (PZLL), poly-L-alanine (PAla) and poly-glycine (PGly) confined in self-ordered AAO containing aligned and straight cylindrical nanopores as a function of pore size were investigated. This research study was carried out by using Differential Scanning Calorimetry (DSC), Fourier Transform Infrared Spectroscopy (FTIR), Solid-State NMR (13C CPMAS NMR), Wide-Angle X-Ray Scattering (WAXS) and Dielectric Spectroscopy (DS). The structural characterization of the nanoconfined PZLL and the nanoconfined PAla revealed the nanorods mostly consist of alpha-helix structure (PZLL) and the nanorods consist of both alpha-helix and beta-sheet structures (PAla) independent of pore diameter. Bulk PZLL exhibits a glass transition temperature (Tg) at about 301 K, while PZLL nanorods showed slightly lower Tg at around 294 K. The dynamic investigation by DS also revealed a small decrease (~4 K) in Tg between bulk and nanoconfined PZLL samples. Subsequently, DS have been employed to study the effect of confinement on the local and global polypeptide dynamics. DS is a very sensitive probe of the local and global (alpha-helical) secondary structure relaxation through the large dipole. The results revealed that the local segmental dynamics, associated with broken hydrogen bonds, speed-up on confinement. The results of this study is of paramount importance, since the understanding the self-assembly, thermodynamics and dynamics of soft mater, Sentetik polipeptitler, proteinlerle olan benzerlikleri ve hiyerarşik olarak kararlı, düzenli konformasyonlara sahip olabilmesi nedeniyle önemli bir polimer grubunu oluştururlar. Polipeptitlerin nanoboyutlu yüzeylerde birçok kullanım alanı olmasına rağmen, bulundukları yüzeyin boyutuna bağlı değişen yapı ve dinamik özelliklerini inceleyen çok az rapor bulunmaktadır [1-4]. Nanoporlu alümina (AAO) içindeki makromoleküller, yığınınkine göre farklı özelliklere sahip olabileceğinden dolayı bu çalışmada; kendiliğinden organize, hizalanmış, düzgün silindirik nanoporlu AAO membran içine sıkıştırılmış, farklı por çaplarına sahip poli(Z-L-lizin) (PZLL), poli-L-alanin (PAla) ve poli-glisin (PGly) nanoçubuklarının yapı ve dinamik özellikleri incelenmiştir. İncelemeler Diferansiyel Taramalı Kalorimetre (DSC), Fourier Dönüşümlü Kızıl Ötesi Spektrometresi (FTIR), Katı Nükleer Manyetik Rezonans Spektrometresi (13C CPMAS NMR), Geniş Açılı X-Ray Işını Saçılımı (WAXS), Dielektrik Spektroskopisi (DS) teknikleri kullanılarak yapılmıştır. Nanoboyutta sıkıştırılmış polipeptitlerin yapısal karakterizasyonu sonucunda por çaplarından bağımsız olarak, çoğunlukla alfa-sarmal ikincil yapısına sahip nanoçubuklar (PZLL) ve hem alfa-sarmal hem de beta-tabaka ikincil yapısına sahip nanoçubuklar (PAla) gözlenmiştir. Yığın PZLL'nin camsı geçiş sıcaklığı 301 K civarında gözlenirken PZLL nanoçubukların camsı geçiş sıcaklıkları 294 K civarında olup yığınınkine göre kısmen daha düşüktür. Sıkıştırılmanın, yerel ve genel polipeptit dinamikleri üzerindeki etkisini gözlemlemek için DS kullanılmıştır. DS, büyük dipol kuvvetlerini kullanarak yerel ve genel (alfa-sarmal) ikincil yapı gevşemelerine oldukça duyarlı bir araçtır. Sonuçlar; kırık hidrojen bağları ile ilişkili olan yerel segmentsel dinamiklerin nano sıkıştırma üzerinde hızlandırıcı etki yaptığını göstermiştir. Bu çalışmanın sonuçları, sıkıştırılmış, bir boyutlu (1D) polimerik malzemelerin kendiliğinden organize olma özelliğinin, termodinamik ve dinam