Publications by authors named "Anamaria Zaharia"

3 Publications

  • Page 1 of 1

Molecularly imprinted films and quaternary ammonium-functionalized microparticles working in tandem against pathogenic bacteria in wastewaters.

J Hazard Mater 2020 11 27;399:123026. Epub 2020 May 27.

National Institute for Research & Development in Chemistry and Petrochemistry ICECHIM, Advanced Polymer Materials and Polymer Recycling Group, Splaiul Independentei 202, 060021, Bucharest, Romania. Electronic address:

Despite major efforts to combat pollution, the presence of pathogenic bacteria is still detected in surface water, soil and even crops due to poor purification of domestic and industrial wastewaters. Therefore, we have designed molecularly imprinted polymer films and quaternary ammonium-functionalized- kaolin microparticles to target specifically Gram-negative bacteria (GNB) and Gram-positive bacteria (GPB) in wastewaters and ensure a higher purification rate by working in tandem. According to the bacteriological indicators, a reduction by 90 % was registered for GNB (total coliforms and Escherichia coli O157) and by 77 % for GPB (Clostridium perfringens) in wastewaters. The reduction rates were confirmed when using pathogen genetic markers to quantify particular types of GNB and GPB, like Salmonella typhimurium (reduction up to 100 %),Campylobacter jejuni (reduction up to 70 %), Enterococcus faecalis (reduction up to 81 %), Clostridium perfringens (reduction up to 97 %) and Shiga toxin-producing Escherichia coli (reduction up to 64 %). In order to understand the bactericidal activity of prepared films and microparticles, we have performed several key analyses such as Cryo-TEM, to highlight the auto-assembly mechanism of components during the films formation, and Si/ C CP/MAS NMR, to reveal the way quaternary ammonium groups are grafted on the surface of kaolin microparticles.
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http://dx.doi.org/10.1016/j.jhazmat.2020.123026DOI Listing
November 2020

Composite Nanogels Based on Zeolite-Poly(ethylene glycol) Diacrylate for Controlled Drug Delivery.

Nanomaterials (Basel) 2020 Jan 22;10(2). Epub 2020 Jan 22.

Advanced Polymer Materials and Polymer Recycling Group, National Institute for Research and Development in Chemistry and Petrochemistry-ICECHIM, 202 Spl. Independentei, 6th District, P.O. Box 35/174, 060021 Bucharest, Romania.

This study presents the design of novel composites nanogels, based on poly(ethylene glycol) diacrylate and natural zeolite particles, that are able to act as materials with controlled drug delivery properties. Natural zeolite‒nanogels composite, with varying zeolite contents, were obtained by an inverse mini-emulsion technique and loaded with 5-fluorouracil, a widely used chemotherapeutic drug. Herein, the possibility of adjusting final properties by means of modifying the preparation conditions was investigated. The prepared composite nanogels are characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). In light of this tunable drug-loading capability, swelling behaviour, and cytotoxicity, these composite nanogels could be highly attractive as drug reservoirs.
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http://dx.doi.org/10.3390/nano10020195DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7075022PMC
January 2020

Straightforward Preparation of Naphtodianthrone-Rich Ethanolic Extracts from Wild St. John's Wort.

J Diet Suppl 2020 31;17(1):88-96. Epub 2018 Oct 31.

National Institute for Research & Development in Chemistry and Petrochemistry ICECHIM, Advanced Polymer Materials and Polymer Recycling Group, Bucharest, Romania.

Separation of naphtodianthrones (NTs) from Hypericum perforatum L. (aerial part of St. John's Wort) is still topical due to some hard-to-beat medicinal attributes of these bioactive compounds. Unfortunately, their low bioavailability (0.06%-0.4%) complicates the extraction process. Therefore, developing straightforward and lower-cost methodologies for NT separation is still a priority. In support of this purpose, for preparing NT formulations from flowers and leaves of wild St. John's Wort (hyperici herba), a cutoff preparative methodology is described herein. Combining Soxhlet extraction and reflux extraction, some concentrated and rather pure NT ethanolic-based formulations without chlorophyl and grease were obtained.
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http://dx.doi.org/10.1080/19390211.2018.1484404DOI Listing
September 2020
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