Geza Lazar

Mr. Geza Lazar


Research Focus & Metrics

Academic Career Length

4Years (2023-Present)

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

Representative Publications

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21 March 2023 in Pharmaceutics
Verified
Journal Article
Open access
PDF file
GLGeza Lazar
Geza Lazar
FNFran Nekvapil
Fran Nekvapil
BGBranko Glamuzina
Branko Glamuzina
TTTudor Tămaş
Tudor Tămaş
Lucian Barbu-TudoranLucian Barbu-Tudoran
Lucian Barbu-Tudoran
Simona Cinta PinzaruSimona Cinta Pinzaru
Simona Cinta Pinzaru
A biogenic carrier for 5-fluorouracil (5-FU) loading and subsequent tableting as a new drug formulation for slow release has been proposed using the biomineral from blue crab carapace. Due to its highly ordered 3D porous nanoarchitecture, the biogenic carbonate carrier could achieve increased effectiveness in colorectal cancer cure provided that the formulation would successfully pass through the gastric acid conditions. Following the recently proven viability of the concept by demonstrating the slow release of the drug from the carrier using the highly sensitive SERS technique, here we investigated the 5-FU release from the composite tablet drug in pH conditions replicating the gastric environment. The released drug from the tablet was studied in solutions with three relevant pH values, pH 2, pH 3, and pH 4. The 5-FU SERS spectral signature for each pH value was used to build calibration curves for quantitative SERS analysis. The results suggested a similarly slow-releasing pattern in acid pH environments to that in neutral conditions. Although biogenic calcite dissolution was expected in acid conditions, the X-ray diffraction and Raman spectroscopy showed preservation of calcite mineral along with the monohydrocalcite during acid solution exposure for two hours. The total released amount in a time course of seven hours, however, was lower in acidic pH solutions, with a maximum fraction of ~40% of the total amount of loaded drug, for pH 2, as opposed to ~80% for neutral values. Nonetheless, these results clearly prove that the novel composite drug retains its slow-releasing character in environmental conditions compatible with the gastrointestinal pH and that it is a viable and biocompatible alternative for oral delivery of anticancer drug to reach the lower gastro-intestinal tract.

16 July 2023 in Water
Verified
Journal Article
Open access
PDF file
FNFran Nekvapil
Fran Nekvapil
MMMaria Mihet
Maria Mihet
GLGeza Lazar
Geza Lazar
Simona Cinta PinzaruSimona Cinta Pinzaru
Simona Cinta Pinzaru
Ana GavrilovićAna Gavrilović
Ana Gavrilović
MSMaria-Loredana Soran
Maria-Loredana Soran
The recovery and recycling of wasted resources are at the forefront of contemporary global issues. Methods of addressing several different issues may go hand-in-hand with each other, such as linking food waste recycling into bio-based adsorbent materials and wastewater treatment. Crustacean exoskeletons are promising candidates for bio-friendly adsorbents; however, maximizing their efficiency requires the optimization of processing technology. Crustacean meat offers an (often luxury) culinary delicacy, while their waste exoskeletons offer opportunities for smart recycling of the magnesian calcite nanoporous biocomposite. Here, we conduct a structural characterization of the exoskeletons of three crustacean species to assess how the extraction of valuable carotenoids affects prospects for the further valorization of their porous powder. The exoskeleton powder’s composition and morphology were investigated by SEM, Raman spectroscopy, FTIR and XRD. The biomineral component magnesian calcite was recorded both in native and in post-extraction exoskeleton powder. Acetone extraction, however, partially removed organic matter from the exoskeletons, resulting in the porosity of the respective powder increasing significantly from below 10 m2 g−1 in the native powder to over 32 m2 g−1 in post-extraction samples of blue crab and spider crab exoskeletons—while the spiny lobster exoskeleton exhibited low porosity, as measured by the BET method. This new insight could improve exoskeleton processing in the sustainable circular economy and applied blue bioeconomy—most notably for adsorbent materials for pollutants dissolved in water or as ordered, nature-derived nanostructured templates.

25 September 2025 in Preprints.org
Verified
Preprint
Open access
PDF file
GLGeza Lazar
Geza Lazar
TTTudor Tămaş
Tudor Tămaş
Lucian Barbu-TudoranLucian Barbu-Tudoran
Lucian Barbu-Tudoran
MVMonica M. Venter
Monica M. Venter
IBIlirjana Bajama
Ilirjana Bajama
Simona Cinta PinzaruSimona Cinta Pinzaru
Simona Cinta Pinzaru
The sustainable conversion of biogenic waste into high-value materials presents a promising approach for addressing environmental and industrial challenges. This work reports an advancement into antioxidant-enriched phosphate minerals derived from green conversion of biogenic calcium carbonates of crustaceans. We demonstrate the effectiveness of Raman technology in controlling conversion using phosphoric acid treatment. The effects of reaction parameters—including acid stoichiometry, granular size distribution, and thermal treatment at 700 °C and 1200 °C—were systematically evaluated. Raman spectroscopy results validated by X-ray diffraction (XRD) and SEM-EDX analyses revealed mixed-phase minerals monetite, brushite, whitlockite or hydroxylapatite resepectively. Notably, reducing particle size enhanced conversion efficiency by increasing the reactive surface area, while the use of excess phosphoric acid facilitated conversion to monocalcium phosphate and promoted the degradation of the organic matrix. Thermal treatment further altered the product composition: heating at 700 °C produced a whitlockite-rich phase, whereas treatment at 1200 °C shifted the balance toward hydroxylapatite. The synthesized calcium phosphate compounds, including hydroxylapatite, monocalcium phosphate, whitlockite, and brushite hold significant practical utility in biomedical applications (such as bone grafts and dental implants), agriculture, and industrial processing. Moreover, we have proven that by controlling the reaction parameters the final product composition can be tailored according to the specific needs, a greener approach yields brushite, monetite, or monocalcium phosphate while a more energy demanding process including heating to 1200 0C yields a high purity hydroxylapatite. This research offers a sustainable analytical route for producing high-purity calcium phosphate materials from wasted biomaterials, contributing to both bioeconomy as well as scientific innovation.

24 October 2025 in Processes
Verified
Journal Article
Open access
PDF file
GLGeza Lazar
Geza Lazar
TTTudor Tămaş
Tudor Tămaş
Lucian Barbu-TudoranLucian Barbu-Tudoran
Lucian Barbu-Tudoran
MVMonica Mihaela Venter
Monica Mihaela Venter
IBIlirjana Bajama
Ilirjana Bajama
Simona Cinta PinzaruSimona Cinta Pinzaru
Simona Cinta Pinzaru
The sustainable conversion of biogenic waste into high-value materials presents a promising approach for addressing environmental and industrial challenges. This work reports an advancement into antioxidant-enriched phosphate minerals derived from green conversion of biogenic calcium carbonates of crustaceans. We demonstrate the effectiveness of Raman technology in controlling conversion using phosphoric acid treatment. The effects of reaction parameters—including acid stoichiometry, granular size distribution, and thermal treatment at 700 °C and 1200 °C—were systematically evaluated. Raman spectroscopy results validated by X-ray diffraction (XRD) and SEM-EDX analyses revealed mixed-phase minerals monetite, brushite, whitlockite or hydroxylapatite, respectively. Notably, reducing particle size enhanced conversion efficiency by increasing the reactive surface area, while the use of excess phosphoric acid facilitated conversion to monocalcium phosphate and promoted the degradation of the organic matrix. Thermal treatment further altered the product composition: heating at 700 °C produced a whitlockite-rich phase, whereas treatment at 1200 °C shifted the balance toward hydroxylapatite. The synthesized calcium phosphate compounds, including hydroxylapatite, monocalcium phosphate, whitlockite, and brushite, hold significant practical utility in biomedical applications (such as bone grafts and dental implants), agriculture, and industrial processing. Moreover, we have proven that by controlling the reaction parameters the final product composition can be tailored according to the specific needs. A greener approach yields brushite, monetite, or monocalcium phosphate, while a more energy-demanding process, including heating to 1200 °C, yields a high-purity hydroxylapatite. This research offers a sustainable analytical route for producing high-purity calcium phosphate materials from wasted biomaterials, contributing to both the bioeconomy as well as scientific innovation.

11 November 2025 in Materials
Verified
Journal Article
Open access
PDF file
IBIlirjana Bajama
Ilirjana Bajama
KMKarlo Maskaric
Karlo Maskaric
GLGeza Lazar
Geza Lazar
TTTudor Tămaş
Tudor Tămaş
CCCodrut Costinas
Codrut Costinas
Simona Cinta PinzaruSimona Cinta Pinzaru
Simona Cinta Pinzaru
Seafood-derived carbonate waste, primarily calcium carbonate (CaCO3), has attracted growing interest for sustainable reuse, yet the unique potential of aged biogenic sources remains underexplored. Blue crab (Callinectes sapidus) shells are particularly distinctive: they consist of Mg-calcite with an intrinsic 3D-porous structure and naturally embedded astaxanthin, a potent antioxidant not found in other calcite- or aragonite-based residues. While organic degradation over time is often assumed to compromise functionality, this study demonstrates that five-years-aged crustacean shell waste retains both its crystallinity and bioactive carotenoids after calibrated ball milling. Across four powder batches produced under distinct milling conditions by varying frequencies and durations, dynamic light scattering confirmed only subtle particle size variation, while Raman spectroscopy, XRD, FT-IR, and SEM-EDX confirmed structural and chemical integrity and highlighted the subtle amorphization induced by slightly different milling parameters, which, in turn, driven to slightly different conversion efficiency into phosphate mineral. Strikingly, all powders underwent rapid transformation into dicalcium phosphate dihydrate (brushite) enriched with carotenoids upon reaction with phosphoric acid. This work reveals, for the first time, that years-aged biogenic Mg-calcite waste not only preserves its naturally embedded carotenoids but also offers a direct route to functional phosphate composites, establishing its untapped value in environmental and biomedical applications.

25 September 2025 in Preprints.org
Verified
Preprint
Open access
PDF file
IBIlirjana Bajama
Ilirjana Bajama
KMKarlo Maskaric
Karlo Maskaric
GLGeza Lazar
Geza Lazar
TTTudor Tămaş
Tudor Tămaş
CCCodrut Costinas
Codrut Costinas
Simona Cinta PinzaruSimona Cinta Pinzaru
Simona Cinta Pinzaru
Biogenic carbonate waste from seafood exploitation, primarily composed of calcium carbonate (CaCO₃), occurs in various polymorphic forms, making it valuable for envi-ronmental and biomedical applications. Mg-calcite from blue crab (Callinectes sapidus) shells is especially promising due to its 3D-ordered porosity and naturally embedded astaxanthin antioxidant, offering advantages over other calcite- or aragonite-based waste. These properties enable its use in pharmaceutical formulations and biostimulants for ac-tive compound loading and controlled release. However, long-term aged biogenic waste may experience organic degradation, potentially altering its physical, chemical, and functional performance. In this study, calibrated ball milling conditions were applied to years-aged biogenic waste to assess structural integrity, crystallinity, and functionality of the resulting powders. Notably, the antioxidant carotenoid remained preserved across all fine powders. Dynamic light scattering revealed that particle size distribution varied subtly between two milling durations (12 and 15 min) and frequencies (25 and 27 Hz). Pigmentation, crystallinity, and repurposing potential of the powders were investigated using Raman spectroscopy, X-ray diffraction (XRD), FT-IR, and SEM-EDX. Ultimately, all four powder batches showed successful conversion into phosphate minerals enriched with antioxidants when treated with phosphoric acid, highlighting the potential of aged shell waste in high-value applications under optimized mechanical and chemical condi-tions.