Grafting of pH-sensitive poly (N,N-dimethylaminoethyl methacrylate-co-2-hydroxyethyl methacrylate) onto HNTS <i>via</i> surface-initiated atom transfer radical polymerization for controllable drug release

J Biomedical Materials Res

Roghani‐Mamaqani

2019

Polydimethylsiloxane‐based polyurethane (PU)/crystalline nanocellulose (CNC) bionanocomposites were produced via in situ prepolymer approach. Also, hexamethylene diisocyanate as aliphatic diisocyanate monomer and 1,4‐butanediol as aliphatic chain extender were used. CNC was incorporated into PU matrix to prepare different PU/CNC bionanocomposites. Effect of CNC content on the properties of the bionanocomposites such as thermal, thermophysical, microstructure, and in vitro cytotoxicity was investigated. According to the results, incorporating CNCs into PU matrix significantly affected the hydrogen bonding between different microstructures of matrix. Adding different amounts of CNCs affected the thermal and thermophysical properties of bionanocomposites. Also, higher amounts of CNCs resulted in lower crystallization of hard segment. Neat PU matrix showed a moderate cytotoxicity behavior against human fibroblast cells. However, incorporating CNCs significantly improved the cytotoxicity behavior of bionanocomposites where by addition of 2 wt % of CNCs, cell viability increased to 90–100%. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 1771–1778, 2019.

Section: Resultsmentioning

confidence: 99%

“…Peaks at 1112 and 1164 cm −1 originated from the stretching vibrations of C O and C C, respectively. 36 Peak at 1060 cm −1 was assigned to bending vibrations of C O C of pyranose ring. 38 Positions of different peaks for neat PU and PU/CNC nanocomposites were similar.…”

Section: Resultsmentioning

confidence: 99%

Evaluation of in vitro cytotoxicity and properties of polydimethylsiloxane‐based polyurethane/crystalline nanocellulose bionanocomposites

Khadivi

J Biomedical Materials Res

Roghani‐Mamaqani

2019

“…In NR sample, peak in the range of 3400 to 3550 cm −1 originated from stretching vibration of –OH groups, which disappeared significantly after modification of NR by CPTES. Also, this peak might originate from the moisture absorption by KBr or samples . In SiNR, peak at 1280 cm −1 referred to Si–CH 2 vibrations .…”

Section: Resultsmentioning

confidence: 99%

Fabrication of high thermal stable cured novolac/Cloisite 30B nanocomposites by chemical modification of resin structure

Javanbakht

Razavi

Polymers for Advanced Techs

et al. 2019

Cloisite 30B as a modified kind of nanoclay was utilized for the formation of 3D network based on novolac resin with high thermal stable properties. Two types of phenolic resins including neat novolac (NR) and modified novolac resin were used to create a compatible matrix with nanoclay. For this purpose, NR modified with (3chloropropyl)triethoxysilane (CPTES) to form SiNR. For improvement of thermal behaviors, Cloisite 30B was dispersed in matrix via ultrasonic waves and cured with hexamethylenetetramine (HMTA) to form 3D network. X-ray diffraction (XRD) analysis was used to measure the d-spacing in intercalated systems and results indicated the optimum amount of clay for appropriate thermal properties. Investigation of the thermal properties of the samples by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) showed that the presence of Cloisite 30B in matrix resulted in much higher thermal stability and char yield with respect to modification of novolac resin originated from formation of 3D Si-O-Si network. Also, cured modified resin and its nanocomposites showed much higher thermal stability than cured NR and its nanocomposites. Such nanocomposite materials with high thermal stability have potential applications in advanced fields such electronic, industrial molds, coatings, adhesives, and aerospace composites.

“…This is ascribed to introduction of hydrogenated ACN molecules those compose of carbon, hydrogen and nitrogen. and N 1S [37][38] with Si content of 2.11% and N content of 2.21% (Table 3). This shows that APTES successfully is grafted on the surface of NCC nanoparticles.…”

Section: Synthesis Of Dendrimer-grafted Ncc Nanoparticlesmentioning

confidence: 99%

Poly(propylene imine) dendrimer-grafted nanocrystalline cellulose: Doxorubicin loading and release behavior

Golshan

Roghani‐Mamaqani

et al. 2017

Polymer

Self Cite

4 th-generation poly(propylene imine) (PPI)-grafted nanocrystalline cellulose (NCC) is prepared via iterative Michael addition of acrylonitrile onto amine-functionalized NCC as initial core and homogeneous hydrogenation of nitrile groups to primary amines. Successful grafting of dendrimers onto NCCs is confirmed by TEM, FT-IR, XPS, TGA and elemental analyses. Also, peripheral primary amines of dendrimer-grafted NCCs are conjugated with folic acid (FA) to investigate bioconjugation effect on drug release behavior of nanostructures. FA-conjugated and nonconjugated nanostructures are loaded with DOX and exposed to environments with different pH values to examine release behavior. Also, drug release kinetics is studied by fitting of experimental data with release models. At different pH values, nonconjugated nanostructures show higher cumulative drug release than FAconjugated systems while loading content was higher for conjugated systems. Drug release from nonconjugated nanostructures is modeled using Korsmeyer-Peppas model that describes release from polymeric matrix. However, in conjugated system, Higuchi model is the best one due to the better solubility of DOX in release media than cavities of grafted dendrimers.