Luminita Cianga

Bio: Luminita Cianga is an academic researcher from Istanbul Technical University. The author has contributed to research in topics: Copolymer & Polymerization. The author has an hindex of 13, co-authored 25 publications receiving 620 citations. Previous affiliations of Luminita Cianga include Istanbul University.

Review paper: Progress in the Field of Conducting Polymers for Tissue Engineering Applications

Abstract: This review focuses on one of the most exciting applications area of conjugated conducting polymers, which is tissue engineering. Strategies used for the biocompatibility improvement of this class of polymers (including biomolecules' entrapment or covalent grafting) and also the integrated novel technologies for smart scaffolds generation such as micropatterning, electrospinning, self-assembling are emphasized. These processing alternatives afford the electroconducting polymers nanostructures, the most appropriate forms of the materials that closely mimic the critical features of the natural extracellular matrix. Due to their capability to electronically control a range of physical and chemical properties, conducting polymers such as polyaniline, polypyrrole, and polythiophene and/or their derivatives and composites provide compatible substrates which promote cell growth, adhesion, and proliferation at the polymer-tissue interface through electrical stimulation. The activities of different types of cells on these materials are also presented in detail. Specific cell responses depend on polymers surface characteristics like roughness, surface free energy, topography, chemistry, charge, and other properties as electrical conductivity or mechanical actuation, which depend on the employed synthesis conditions. The biological functions of cells can be dramatically enhanced by biomaterials with controlled organizations at the nanometer scale and in the case of conducting polymers, by the electrical stimulation. The advantages of using biocompatible nanostructures of conducting polymers (nanofibers, nanotubes, nanoparticles, and nanofilaments) in tissue engineering are also highlighted.

Synthesis and characterization of maleimide (Co)polymers with pendant benzoxazine groups by photoinduced radical polymerization and their thermal curing

Abstract: A maleimide monomer with benzoxazine and nitrile functionalities, 1-[3-(4-cyano-phenyl)-3,4-dihydro-2H-benzo[e] [1,3]oxazine-6-yl]-maleimide (MI-Bz-4CN), was prepared using N-(4-hydroxyphenylmaleimide) (HPMI), formaldehyde, and 4-aminobenzonitrile. Photoinduced radical polymerization was employed to prepare the alternating copolymers of MI-Bz-4CN with styrene (St) at room temperature using ω,ω-dimethoxy-ω-phenylacetophenone (DMPA) as photoinitiator. These polymers were characterized by FT-IR and 1H NMR. Monomer reactivity ratios for the studied monomer pair were calculated by using extended Kelen–Tudos (Ex. K–T) method. Structural parameters of the copolymers were obtained calculating the diad monomer sequence fractions. Copolymers' compositions and the monomer reactivity ratios suggest the alternating nature of the copolymerization. Thermal behavior of the alternating copolymers P(MI-Bz-4CN-alt-St) was also investigated by thermogravimetrical analysis (TGA) and differential scanning calorimetry (DSC). The ring-opening polymerization of the pendant benzoxazine groups of the copolymers was monitored by DSC and FT-IR studies. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2774–2786, 2007

Electrochromic properties and electrochromic device application of copolymer of N‐(4‐(3‐thienyl methylene)‐oxycarbonylphenyl)maleimide with thiophene

Abstract: A new copolymer of N-(4-(3-thienyl methylene)-oxycarbonylphenyl)maleimide (MBThi) with thiophene [P(MBThi-co-Th)] was synthesized electrochemically in the presence of tetrabutylammonium tetrafluoroborate as the supporting electrolyte, in acetonitrile/borontrifluoride ethylether solvent mixture (80 : 20, v/v). Spectroelectrochemical analysis of the resulting copolymer reflected electronic transitions at 440, 730, and ∼1000 nm, revealing π–π* transition, polaron, and bipolaron band formation, respectively. Switching ability was evaluated by a kinetic study via measuring the transmittance (%T) at the maximum contrast. Dual-type polymer electrochromic devices (ECDs) based on P(MBThi-co-Th) and poly(ethylene dioxythiophene) (PEDOT) were constructed. Spectroelectrochemistry, switching ability, and stability of the devices were investigated by UV–vis spectroscopy and cyclic voltammetry. These devices exhibit low switching voltages (between 0.0 and +2.0 V) and short switching times with reasonable switching stability under atmospheric conditions. © 2006 Wiley Periodicals, Inc. J Appl PolymSci 102: 4500–4505, 2006

Electrically conductive polymers and composites for biomedical applications

Abstract: Electrically conductive polymeric materials have recently attracted considerable interest from academic and industrial researchers to explore their potential in biomedical applications such as in biosensors, drug delivery systems, biomedical implants and tissue engineering. Conventional conductive homopolymers such as polypyrrole and PEDOT show promising conductivity for these applications, however their mechanical properties, biocompatibility and processability are often poor. This has led to more recent attention being directed towards conductive polymeric composites comprised of biostable/biocompatible polymers with dispersed conductive fillers such as graphene, carbon nanotubes and metallic nanoparticles. The major objective of this paper is to provide an up to date review of the recent investigations conducted in the development of conductive polymer composites focussing on the methods of their preparation, underlying concepts of their conductivity and the ways to tailor their properties. Furthermore, recent progress made in conventional conducting polymers and their composites/blends for biomedical applications is also discussed.

Conductive Polymers: Opportunities and Challenges in Biomedical Applications

Abstract: Research pertaining to conductive polymers has gained significant traction in recent years, and their applications range from optoelectronics to material science. For all intents and purposes, conductive polymers can be described as Nobel Prize-winning materials, given that their discoverers were awarded the Nobel Prize in Chemistry in 2000. In this review, we seek to describe the chemical forms and functionalities of the main types of conductive polymers, as well as their synthesis methods. We also present an in-depth analysis of composite conductive polymers that contain various nanomaterials such as graphene, fullerene, carbon nanotubes, and paramagnetic metal ions. Natural polymers such as collagen, chitosan, fibroin, and hydrogel that are structurally modified for them to be conductive are also briefly touched upon. Finally, we expound on the plethora of biomedical applications that harbor the potential to be revolutionized by conductive polymers, with a particular focus on tissue engineering, regene...

The return of a forgotten polymer : Polycaprolactone in the 21st century

Abstract: During the resorbable-polymer-boom of the 1970s and 1980s, polycaprolactone (PCL) was used in the biomaterials field and a number of drug-delivery devices. Its popularity was soon superseded by faster resorbable polymers which had fewer perceived disadvantages associated with long term degradation (up to 3-4 years) and intracellular resorption pathways; consequently, PCL was almost forgotten for most of two decades. Recently, a resurgence of interest has propelled PCL back into the biomaterials-arena. The superior rheological and viscoelastic properties over many of its aliphatic polyester counterparts renders PCL easy to manufacture and manipulate into a large range of implants and devices. Coupled with relatively inexpensive production routes and FDA approval, this provides a promising platform for the production of longer-term degradable implants which may be manipulated physically, chemically and biologically to possess tailorable degradation kinetics to suit a specific anatomical site. This review will discuss the application of PCL as a biomaterial over the last two decades focusing on the advantages which have propagated its return into the spotlight with a particular focus on medical devices, drug delivery and tissue engineering.