Antoniya Toncheva

• PhD
• Research Assistant at Bulgarian Academy of Sciences

The scientific and technological progress reached a point that allows for exciting 3D printing technologies. Applied to the additive manufacturing industry, said technologies offer the possibility to create polymer devices with controlled architectures such as personalized prototypes, hydrogels, biomedical and flexible electronic devices, as well a...

Shape-memory polymers (SMPs) as stimuli-responsive shape-changing polymers are of great interest for fundamental research and technological innovation. In this contribution, a brief review of the recent trends in the field of SMPs is presented with particular focus on their structure, shape-memory effects and working mechanism. A special attention...

During the last years, shape-memory polymers (SMPs) are being gained a key-position in the realm of actuating applications from daily life products to biomedical and aeronautic devices. Most of these SMPs however rely mainly on shape changes upon direct heat exposure or after stimulus conversion (e.g. magnetic field and light) to heat, but this con...

A simple and straightforward approach to produce solvent and vapor-based actuating materials is developed in this work. These actuators are based on rigidity gradient obtained in bilayer architectures made of reversibly cross-linked poly(ε-caprolactone) (PCL) networks wherein functional nanofillers, i.e. multi-walled carbon nanotubes (MWCNTs), are...

Shape-memory polymers (SMPs) are currently a subject of tremendous attention from both - the academic and industrial fields and are playing a major role in inspiring the design of a class of polymer materials. Their attractive properties related to multi-step shape-changing upon exposure to an appropriate stimulus, as well as high elastic deformati...

In this study, a sustainable cellulose-based flame-retardant additive was developed, characterized, and incorporated into polypropylene (PP). Microcrystalline cellulose (Cel) was chemically modified with P2O5 using the solvent-free ball-milling mechanochemistry approach at room temperature. This modification enabled phosphorus grafting onto cellulo...

Invited for this month′s cover, the researchers from UTCBS and CiTCoM from Université Paris Cité (Paris, France), as well as Materia Nova (Mons, Belgium). The image emphasizes the deep eutectic solvent preparation thanks to hydrogen bond acceptor and donor interactions for drugs formulation and therapeutic applications. The Review itself is availab...

In the spirit of circular economy and sustainable chemistry, the use of environmentally friendly chemical products in pharmacy has become a hot topic. In recent years, organic solvents have been the subject of a great range of restriction policies due to their harmful effects on the environment and toxicity to human health. In parallel, deep eutect...

Nowadays, due to their natural availability, renewability, biodegradability, nontoxicity, light weight and relatively low cost, natural fibers, especially lignocellulosic fibers, present attractive potential to substitute non-eco-friendly synthetic fibers. In this study, Ziziphus jujuba fibers were used, thanks to their low lignin content, as an al...

Biobased and biocompatible polymers, such as polyhydroxyalkanoates (PHAs), are of great interest for a large range of applications in the spirit of green chemistry and upcoming reuse and recycling strategies. Polyhydroxybutyrate (PHB), as a promising biocompatible polymer belonging to PHAs, is subject to increased research concern regarding the hig...

Thermoplastic polyurethanes (TPUs) are proposed as suitable solution for the fabrication of biocompatible catheters with appropriate mechanical parameters and confirmed antibacterial and cytocompatible properties. For this purpose, a series of quaternary ammonium salts (QASs) and quaternary phosphonium salts (QPSs) based monomers were prepared foll...

During the past years, the synthesis of polymer prodrug structures, based on natural phytochemical compounds with a great range of valuable biological properties, has become a promising solution in cancer prevention, imaging, and detection. Curcumin (Curc) remains one of the most studied natural products, due to the impressive palette of biological...

Active ethylene scavenging in fresh produce involves the use of adsorbers and oxidizers, such as, potassium permanganate, activated carbon, clays and zeolites, often integrated as sachets, labels, liners, or films. Although many studies have been done to develop novel ethylene scavengers, only a few of them have analyzed the ethylene removal kineti...

The cover image by Franck Meyer and his co‐authors highlights the fabrication of thermoplastic polyurethanes (TPUs) targeting the development of catheters for direct biomedical application. First, the reaction conditions were tuned to tailor the mechanical properties of the resulting TPUs. Then, the incorporation of only 0.5 mol% of a biologically...

The production of plastic has grown exponentially over the past few decades and with it the amount of plastic waste leaking in the environment, where it fragments into micro- and nanoplastics. This problematic situation stresses the need for increased plastic collection, recycling and reuse rates. Extrusion-based additive manufacturing (AM) and esp...

Vulcanized and devulcanized ground tire rubber microparticles have been used as a minor phase in acrylonitrile butadiene styrene copolymer (ABS) and thermoplastic polyolefins (TPO) for the development of materials with desired functionalities by 3D printing. These polymers have been selected because they (i) present part of the plastic waste genera...

Natural and synthetic rubber is gaining increased interest in various industrial applications and daily life sectors (automotive industry, acoustic and electrical isolators, adhesives, impermeable surfaces, and others) due to its remarkable physicomechanical properties, excellent durability, and abrasive resistance. These great characteristics are...

Thermoplastic polyurethanes (TPUs) bear tunable chemistry offering the possibility to develop a rich palette of physio‐mechanical properties, making the materials suitable for various fields of application. The great variety in TPUs properties comes from the choices of the monomers and the reaction conditions. Herein, the mechanical properties of t...

Poly(ethylene terephthalate) (PET) is known for its various useful characteristics, including its applicability in cardiovascular applications, more precisely as synthetic bypass grafts for large diameter (≥ 6 mm) blood vessels. Although it is widely used, PET is not an optimal material as it is not interactive with endothelial cells, which is requ...

Minimally invasive implantation of subdural electrodes can dramatically benefit the patients with various neurological diseases. In modern clinical practice, the implantation procedure of the electrode arrays remains traumatic for patients and increases postoperative infection risk. Here we report a design and insertion technique of thermally activ...

During the last years, great progress was made in material science in terms of concept, design and fabrication of new composite materials with conferred properties and desired functionalities. The scientific community paid particular interest to active soft materials, such as soft actuators, for their potential as transducers responding to various...

Electrospun membranes containing curcumin were prepared from poly(L-co-D,L-lactic) acid and polyvinylpyrrolidone. The effect of curcumin concentration on the solution viscosity and the morphology of fiber was studied. Curcumin solubility in aqueous solutions was enhanced by the formation of curcumin/polyvinylpyrrolidone water-soluble complex. Curcu...

The increased technological progress in materials science fabrication is changing the dynamics of the scientific community with short adaptability deadlines, while framing a new set of competitive challenges and needs. As a result, material design requires a multidisciplinary networking, where natural sciences (e.g. biology, chemistry, physics) mee...

Inspired by nature, we herein demonstrate a family of multi-responsive hydrogel-based actuators that are encoded with anisotropic swelling behavior to provide rapid and controllable motion. Fabrication of the proposed anisotropy-encoded hydrogel actuators relies on the high resolution stereolithography 3D printing of functionally graded structures...

New hybrid fibrous materials from polyacrylonitrile (PAN) and nanosized zinc oxide have been prepared by electrospinning or by combining electrospinning and electrospraying techniques. Electrospinning of PAN/nanosized zinc oxide dispersion leads to the production of mats with nanofiller distributed mainly in the bulk of the fibers. Electrospinning...

Antibacterial micro- and nanofibrous materials based on polylactide (PLA) and polyethylene glycol (PEG) were prepared by electrospinning. PEG incorporation was achieved by its physical blending with or chemical grafting on PLA. The role of the incorporation method on the surface wettability, the thermal, the mechanical and the biological properties...

New microfibrous materials from polylactide and polyvinylpyrrolidone or polyethylene glycol loaded with the natural polyphenolic compound curcumin have been prepared by one-pot electrospinning. The incorporation of curcumin in the fibers contributes to shielding curcumin from photodestruction and to enhancement of the mechanical properties of the f...

Microfibrous materials with a targeted design based on poly(L-lactic acid) (PLA) and poly(!-caprolactone) (PCL) were prepared by electrospinning and by combining electrospinning and electrospraying. Several approaches were used: (i) electrospinning of a common solution of the two polymers, (ii) simultaneous electrospinning of two separate solutions...

An advanced centrifugal electrospinning setup is proposed for the fabrication of non-woven textiles from polymer solutions using a pivotal feed unit and stationary collectors of large diameters and different designs: cylindrical collectors or collectors consisting of circularly arranged metal strips. The use of a collector composed of strips enable...

Fibrous materials of poly(l-lactide-co-d,l-lactide), poly(l-lactide-co-d,l-lactide)/poly(ethylene glycol), and curcumin were prepared by electrospinning. The incorporation of poly(ethylene glycol) in the fibers caused a decrease in the mean fiber diameters down to 700 nm and in the water contact angle value, the latter being equal to 0 at poly(l-la...

For the first time the preparation of defect-free fibers from immiscible blends of high molar mass poly(lactic acid) (PLA) and poly(butylene succinate) (PBS) in the whole range of the polyesters weight ratios is shown. Electrospinning using the solvent-nonsolvent approach proved most appropriate. Moreover, electrospinning revealed crucial for the o...

The effect of the electrospinning process parameters on the morphology, alignment and self-organization of the fibers into bundles and/or yarns are outlined here. The fabrication of polylactide materials containing ionic drugs by electrospinning is emphasized. The main approaches used for the preparation of electrospun drug-loaded materials: electr...

Microfibrous materials based on poly(l-lactide-co-d,l-lactide) (coPLA) and coPLA/poly(ethylene glycol) (PEG) containing a fluoroquinolone antibiotic: ciprofloxacin hydrochloride (Cipro), levofloxacin hemihydrate (Levo) or moxifloxacin hydrochloride (Moxi) were obtained by electrospinning. The presence of Moxi led to an increase in the conductivity...

This study reveals and highlights the importance of the electrospinning set-up to avoid the occurrence of ionic interaction between drugs during the preparation of dual drug loaded electrospun fibrous materials. Poly(L-lactide) (PLA)-based fibrous materials containing diclofenac sodium (DS) and lidocaine hydrochloride (LHC) were prepared by dual sp...

Micro- and nanofibrous electrospun poly(L-lactide) (PLA) and PLA/poly(ethylene glycol) (PEG) membranes containing diclofenac sodium (DS), lidocaine hydrochloride (LHC), benzalkonium chloride (BC), or combinations thereof (DS/LHC and DS/LHC/BC) have been developed. The addition of low molecular weight organic salts to the spinning PLA and PLA/PEG so...

Bundle membranes were made by electrospinning poly(L-lactide) (PLLA) and PLLA/poly(ethylene glycol) (PEG) using the ionic properties of diclofenac sodium (DS), lidocaine hydrochloride (LHC), benzalkonium chloride (BC), and combinations thereof. The self-bundling of the fibers was initiated by using a designed grounded multi-needle electrode. Comput...