Deana Georgieva

Dr. Deana Georgieva

orcid

Research Focus & Metrics

Academic Career Length

25Years (2002-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
4 August 2023 in Biomedicines
Verified
Journal Article
Open access
PDF file
Stoyanka Atanasova NikolovaStoyanka Atanasova Nikolova
Stoyanka Atanasova Nikolova
Miglena MilushevaMiglena Milusheva
Miglena Milusheva
Vera Nikolaeva GledachevaVera Nikolaeva Gledacheva
Vera Nikolaeva Gledacheva
Mehran Feizi-DehnayebiMehran Feizi-Dehnayebi
Mehran Feizi-Dehnayebi
LKLidia Kaynarova
Lidia Kaynarova
MTMina Todorova
Mina Todorova
Anticoagulants prevent the blood from developing the coagulation process, which is the primary cause of death in thromboembolic illnesses. Phenindione (PID) is a well-known anticoagulant that is rarely employed because it totally prevents coagulation, which can be a life-threatening complication. The goal of the current study is to synthesize drug-loaded Ag NPs to slow down the coagulation process. Methods: A rapid synthesis and stabilization of silver nanoparticles as drug-delivery systems for phenindione (PID) were applied for the first time. Results: Several methods are used to determine the size of the resulting Ag NPs. Additionally, the drug-release capabilities of Ag NPs were established. Density functional theory (DFT) calculations were performed for the first time to indicate the nature of the interaction between PID and nanostructures. DFT findings supported that galactose-loaded nanostructure could be a proper delivery system for phenindione. The drug-loaded Ag NPs were characterized in vitro for their antimicrobial, cytotoxic, and anticoagulant activities, and ex vivo for spasmolytic activity. The obtained data confirmed the drug-release experiments. Drug-loaded Ag NPs showed that prothrombin time (PT, sec) and activated partial thromboplastin time (APTT, sec) are approximately 1.5 times longer than the normal values, while PID itself stopped coagulation at all. This can make the PID-loaded Ag NPs better therapeutic anticoagulants. PID was compared to PID-loaded Ag NPs in antimicrobial, spasmolytic activity, and cytotoxicity. All the experiments confirmed the drug-release results.

1 July 2004 in Analytica Chimica Acta
Verified
Journal Article
Closed access
DHDimitar Hristozov
Dimitar Hristozov
CDClaudia E Domini
Claudia E Domini
VKVeselin Kmetov
Veselin Kmetov
VSVioleta Milenkova Stefanova
Violeta Milenkova Stefanova
DGDeana Georgieva
Deana Georgieva
Antonio CanalsAntonio Canals
Antonio Canals

1 May 2012 in Spectrochimica Acta Part B: Atomic Spectroscopy
Verified
Journal Article
Closed access
KIKrasimir Ivanov
Krasimir Ivanov
PZPenka Zaprjanova
Penka Zaprjanova
MPMilena Petkova
Milena Petkova
VSVioleta Milenkova Stefanova
Violeta Milenkova Stefanova
VKVeselin Kmetov
Veselin Kmetov
VAViolina Angelova
Violina Angelova

30 May 2023 in Biomedicines
Verified
Journal Article
Open access
PDF file
MTMina Todorova
Mina Todorova
Miglena MilushevaMiglena Milusheva
Miglena Milusheva
LKLidia Kaynarova
Lidia Kaynarova
DGDeana Georgieva
Deana Georgieva
VDVassil Delchev
Vassil Delchev
Stoyanka Atanasova NikolovaStoyanka Atanasova Nikolova
Stoyanka Atanasova Nikolova
Chronic, multifactorial illnesses of the gastrointestinal tract include inflammatory bowel diseases. One of the greatest methods for regulated medicine administration in a particular region of inflammation is the nanoparticle system. Silver nanoparticles (Ag NPs) have been utilized as drug delivery systems in the pharmaceutical industry. The goal of the current study is to synthesize drug-loaded Ag NPs using a previously described 3-methyl-1-phenylbutan-2-amine, as a mebeverine precursor (MP). Methods: A green, galactose-assisted method for the rapid synthesis and stabilization of Ag NPs as a drug-delivery system is presented. Galactose was used as a reducing and capping agent forming a thin layer encasing the nanoparticles. Results: The structure, size distribution, zeta potential, surface charge, and the role of the capping agent of drug-loaded Ag NPs were discussed. The drug release of the MP-loaded Ag NPs was also investigated. The Ag NPs indicated a very good drug release between 80 and 85%. Based on the preliminary results, Ag NPs might be a promising medication delivery system for MP and a useful treatment option for inflammatory bowel disease. Therefore, future research into the potential medical applications of the produced Ag NPs is necessary.

24 June 2020 in Water
Verified
Journal Article
Open access
PDF file
Gana GechevaGana Gecheva
Gana Gecheva
Vesela YanchevaVesela Yancheva
Vesela Yancheva
IVIliana Velcheva
Iliana Velcheva
EGElenka Georgieva
Elenka Georgieva
SSStela Stoyanova
Stela Stoyanova
Ivelin MollovIvelin Mollov
Ivelin Mollov
For the first time, transplants with moss-bags and mussels together were applied to study the water quality in standing water bodies. The tested species: Fontinalis antipyretica Hedw. and Sinanodonta woodiana (Lea, 1834) were collected from unpolluted sites and analyzed to obtain background levels. Then, the moss and mussels were left in cages for a period of 30 days in three reservoirs where both are not present naturally. Two of the reservoirs suffer from old industrial contamination and one is affected by untreated wastes. Twenty-four compounds were studied, among them trace elements Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Zn and organic priority substances: six polybrominated diphenyl ethers (PBDEs) congeners and short-chain chlorinated paraffins (SCCPs). The trace element accumulation was significant after the exposition period in all studied stations. PBDEs and SCCPs were also accumulated up to two times more in the moss tissues. PBDEs in the mussels exceeded the environmental quality standard (EQS). The applied combined transplants, and especially the moss-bags, revealed severe contamination with heavy metals not detected by the water samples. The moss and the mussel followed a different model of trace element and PBDEs accumulation. The SCCPs levels were alarmingly high in all plant samples. The study confirmed PBDEs and SCCPs as bioaccumulative compounds and suggested that an EQS for SCCPs in biota needs to be established.

10 July 2012 in Journal of Analytical Atomic Spectrometry
Verified
Journal Article
Closed access
PDF file
VSVioleta Milenkova Stefanova
Violeta Milenkova Stefanova
DGDeana Georgieva
Deana Georgieva
VKVeselin Kmetov
Veselin Kmetov
IRIvan Roman
Ivan Roman
Antonio CanalsAntonio Canals
Antonio Canals
The applicability of MnFe2O4 nanoparticles as a new sorbent for group pre-concentration of V, Co, Ni, Cu, Zn, As, Se, Cd and Pb was investigated and compared with that of magnetite nanoparticles. A solid-phase extraction (SPE) of target analytes based on sorption of their hydrophobic complexes with ammonium pyrrolidine dithiocarbamate (APDC) on the surface of unmodified nanoparticles (NPs) was optimized. Magnetic NPs with retained metal complexes were easily separated from the bulk solution by a permanent magnet applied for 5 min. Analyte restoration in the final solution was accomplished by heating with 0.5 mL of 7 mol L−1 nitric acid. The obtained solutions were suitable for continuous nebulization in ICP-MS. Spectral and non-spectral matrix effects for urine analysis (direct and after SPE) were studied and adequate calibration strategies are suggested. Under optimized conditions the magnetically assisted SPE procedure enables enrichment of target analytes by factors of between 7.4 and 10, with linear dynamic ranges of 1–100 μg L−1 for V, Co, Ni, Cd, Pb and 10–1000 μg L−1 for Zn, As, Se and method detection limits in the interval 0.01–0.7 μg L−1. The relative standard deviations (RSD%, for 10 μg L−1 V, Co, Ni, Cd, Pb and for 100 μg L−1 Zn, As, Se, n = 6) were less than 5.5%. The accuracy of the method was evaluated by analysing urine certified reference material Seronorm™ Trace Elements Urine 201205 and obtained recoveries were in the range 85–109%. For correct determination of As and Se in urine, a preliminary microwave sample treatment with a mixture HNO3 + H2O2 was needed, but it led to a worsening of method detection limits. The developed method was successfully applied for analysis of human urine.