Gabriel Lucian Radu
@incdsb.ro
Centre of Bioanalysis
INCDSB Bucuresti
RESEARCH, TEACHING, or OTHER INTERESTS
Analytical Chemistry, Bioengineering, Agricultural and Biological Sciences, Biomaterials
Scopus Publications
Scopus Publications
Sandra A. V. Eremia, Camelia Albu, Gabriel-Lucian Radu, Andreia Alecu, Alice G. Stoica, and Elena Brinduse
MDPI AG
In recent years, various studies have been carried out to increase the concentration of antioxidant active principles in red wines as a consequence of the effects of winemaking techniques on the polyphenols content. In this study, in order to obtain the most optimal wine in terms of content and efficiency of antioxidant activity, various winemaking technologies (punching-down and pumping-over maceration) were tried with diverse gradations (Feteasca Neagra and Cabernet Sauvignon wines) and the addition of different concentrations of melatonin in must. Suitable HPLC and spectrophotometric methods were used to follow the evolution of the antioxidant compounds from wines during aging (for 12 months). After comparing the acquired results, an increase was observed in the antioxidant compound concentrations, particularly in resveratrol (85%), peonidin-3-glucoside (100%) or cyanidin-3-glucoside (100%), and antioxidant activity (10–40%). The most enriched wine was obtained in the case of Feteasca Neagra by the addition of 0.5 mg of melatonin per 1 kg of must using the punch-down technology and, in the case of Cabernet Sauvignon, by the addition of 0.05 mg of melatonin per 1 kg of must using the pumping-over technique. This study can provide winemakers with an approach to enhance red wines with antioxidant compounds.
Gabriela Paun, Elena Neagu, Andreia Alecu, Camelia Albu, Ana-Maria Seciu-Grama, and Gabriel Lucian Radu
MDPI AG
The present study evaluated the antioxidant and antidiabetic properties of Medicago sativa and Solidago virgaurea extracts enriched in polyphenolic compounds. The extracts were obtained by accelerated solvent extraction (ASE) and laser irradiation. Then, microfiltration was used for purification, followed by nanofiltration used to concentrate the two extracts. The obtained extracts were analyzed to determine their antioxidant activity using DPPH radical scavenging and reducing power methods. The antidiabetic properties have been investigated in vitro on a murine insulinoma cell line (β-TC-6) by the inhibition of α-amylase and α-glucosidase. M. sativa obtained by laser irradiation and concentrated by nanofiltration showed the highest DPPH• scavenging (EC50 = 105.2 ± 1.1 µg/mL) and reducing power activities (EC50 = 40.98 ± 0.2 µg/mL). M. sativa extracts had higher inhibition on α-amylase (IC50 = 23.9 ± 1.2 µg/mL for concentrated extract obtained after ASE, and 26.8 ± 1.1), while S. virgaurea had the highest α-glucosidase inhibition (9.3 ± 0.9 µg/mL for concentrated extract obtained after ASE, and 8.6 ± 0.7 µg/mL for concentrated extract obtained after laser extraction). The obtained results after evaluating in vitro the antidiabetic activity showed that the treatment with M. sativa and S. virgaurea polyphenolic-rich extracts stimulated the insulin secretion of β-TC-6 cells, both under normal conditions and under hyperglycemic conditions as well. This paper argues that M. sativa and S. virgaurea polyphenolic-rich extracts could be excellent natural sources with promising antidiabetic potential.
Elena Neagu, Gabriela Paun, Camelia Albu, Oana Teodora Apreutesei, and Gabriel Lucian Radu
MDPI AG
Recently, there has been increased interest in the discovery of new natural herbal remedies for treating diabetes and inflammatory diseases. In this context, this work analyzed the antidiabetic and anti-inflammatory potential of Artemisia absinthium, Artemisia vulgaris and Trigonella foenum-graecum herbs, which have been studied less from this point of view. Therefore, extracts were prepared and processed using membrane technologies, micro- and ultrafiltration, to concentrate the biologically active principles. The polyphenol and flavone contents in the extracts were analyzed. The qualitative analysis of the polyphenolic compounds was performed via HPLC, identifying chlorogenic acid, rosmarinic acid and rutin in A. absinthium; chlorogenic acid, luteolin and rutin in A. vulgaris; and genistin in T. foenum-graecum. The antidiabetic activity of the extracts was analyzed by testing their ability to inhibit α-amylase and α-glucosidase, and the anti-inflammatory activity was analyzed by testing their ability to inhibit hyaluronidase and lipoxygenase. Thus, the concentrated extracts of T. foenum-graecum showed high inhibitory activity on a-amylase—IC50 = 3.22 ± 0.3 μg/mL—(compared with acarbose—IC50 = 3.5 ± 0.18 μg/mL) and high inhibitory activity on LOX—IC50 = 19.69 ± 0.52 μg/mL (compared with all standards used). The concentrated extract of A. vulgaris showed increased α-amylase inhibition activity—IC50 = 8.57 ± 2.31 μg/mL—compared to acarbose IC50 = 3.5 ± 0.18 μg/mL. The concentrated extract of A. absinthium showed pronounced LOX inhibition activity—IC50 = 19.71 ± 0.79 μg/mL—compared to ibuprofen—IC50 = 20.19 ± 1.25 μg/mL.
Alexandra-Gabriela Oancea, Catalin Dragomir, Arabela Untea, Mihaela Saracila, Raluca Turcu, Ana Cismileanu, Ioana Boldea, and Gabriel Lucian Radu
MDPI AG
Brewer’s spent yeast (BSY) is a byproduct of the beer industry, rich in proteins and bioactive compounds. The effects of BSY were investigated through a 6-week feeding trial on 30 lactating dairy Blackhead sheep (54.7 ± 5.66 kg, 177.34 days in milk) distributed under a completely randomised design in two groups: a control group (with soybean meal and sunflower meal as protein sources), and a BSY group, where soybean meal was totally replaced by BSY (5.4% inclusion, DM basis). The inclusion of BSY led to a 25% decrease in ruminal propionate and in the acetate/propionate ratio. BSY influenced the milk fatty acid profile by significantly decreasing the omega 6: omega 3 ratio and increasing the contents of caproic, capric, and lauric acids. Also, the inclusion of BSY was associated with an increase in the milk’s total polyphenols. Consistently, determinations of the parameters of the milk fat’s oxidative stability revealed a decrease in conjugated diene contents. Moreover, the mineral contents of milk were influenced, with an increase in Ca content noted. Overall, these results indicate that BSY represents an alternative feedstuff for ruminants’ nutrition, which could have the potential to induce changes in ruminal fermentation and milk composition that are beneficial for consumers.
Daniel Preda, Maria Lorena Jinga, Iulia Gabriela David, and Gabriel Lucian Radu
MDPI AG
A new method for the determination of the antiplatelet drug dipyridamole (DIP) in pharmaceuticals using a molecularly imprinted polymer (MIP)-modified pencil graphite electrode (PGE) is proposed. The modified electrode was prepared simply and rapidly by electropolymerization of caffeic acid (CA) in the presence of DIP and subsequent DIP extraction with ethanol, resulting in a cost-effective, eco-friendly disposable modified electrode (MIP_PGE). Several working conditions (monomer and template concentration, number of voltametric cycles, scan rate extraction time, and solvent) for the MIP_PGE preparation were optimized. The differential pulse voltammetric (DPV) oxidation signal of DIP obtained at MIP_PGE was 28% higher than that recorded at bare PGE. Cyclic voltammetry emphasized DIP irreversible, pH-dependent, diffusion-controlled oxidation at MIP_PGE. Differential pulse and adsorptive stripping voltammetry at MIP_PGE in phosphate buffer solution pH = 7.00 were applied for the drug quantitative determination in the range of 1.00 × 10−7–1.00 × 10−5 and 1.00 × 10−8–5.00 × 10−7 mol/L DIP, respectively. The obtained limits of detection were at the tens nanomolar level.
Gabriel-Lucian Radu, Simona Carmen Lițescu, Alin Enache, Camelia Albu, and Sandra A. V. Eremia
MDPI AG
In recent years, new sensor-based technologies have been developed to meet the demand for rapid and accurate analysis of food and environment, as food safety and environmental monitoring are very important concerns nowadays. In this context, considerable attention has been paid to the development and design of electrochemical sensors, as these offer a number of advantages, such as portability, ease of use, low costs and fast response times. Molecularly imprinted polymers (MIPs) are robust synthetic polymers with special cavities designed for a target molecule, and they are used as selective tools through a mechanism of molecular recognition. Graphene is a 2D crystalline carbon that forms either a single or a coupled layer of hexagonally arranged carbon atoms and is referred to as a “wonder material”. The use of these two structures in the development of electrochemical sensors gives the newly created analytical tool enhanced properties, such as improved sensitivity and selectivity, low detection limit, good stability and reusability. This review presents an overview of the recent research regarding the use of MIPs and graphene in the development of electrochemical sensors for food and environmental analyses, critically discusses the pros and cons, and gives perspectives for further developments in this field.
Madalina-Petruta Bucur, Maria-Cristina Radulescu, Gabriel Lucian Radu, and Bogdan Bucur
MDPI AG
Ultrasound generates cavities in liquids with high-energy behaviour due to large pressure variations, leading to (bio)chemical effects and material modification. Numerous cavity-based treatments in food processes have been reported, but the transition from research to industrial applications is hampered by specific engineering factors, such as the combination of several ultrasound sources, more powerful wave generators or tank geometry. The challenges and development of cavity-based treatments developed for the food industry are reviewed with examples limited to two representative raw materials (fruit and milk) with significantly different properties. Both active compound extraction and food processing techniques based on ultrasound are taken into consideration.
Sandra A. V. Eremia, Camelia Albu, Gabriel-Lucian Radu, Andreia Alecu, and Elena Brinduse
MDPI AG
Until recently, the main antioxidant role among wine constituents was attributed to polyphenolic compounds, but once the presence of melatonin in wines was confirmed, an interesting new field of research opened up due to its possible synergistic effects with other antioxidants in the winemaking process, which may lead to a change in the profile of polyphenolic compounds and antioxidant activity. In order to investigate the evolution of active principles from the phenylpropanoid metabolism associated with the synergistic effects of melatonin, for the first time, a melatonin treatment was performed in the pre-stage of the different winemaking processes of Feteasca Neagra and Cabernet Sauvignon wines with different melatonin concentrations. After comparing the acquired results for the evolution of the polyphenolic compound profile and antioxidant activity of treated wines, we ascertained an increase in the antioxidant compound concentrations, especially in resveratrol, quercetin, and cyanidin-3-glucoside, directly proportional to the used melatonin concentration; an intensification in activity of PAL and C4H enzymes; and the modification in the expression of specific anthocyanin biosynthesis genes, especially UDP-D-glucose-flavonoid-3-O-glycosyltransferase. It was also shown that the application of melatonin in the pre-stage of the winemaking process can be successfully used to obtain red wines with increased antioxidant activity (almost 14%).
Elena Neagu, Gabriela Paun, Camelia Albu, Sandra Ana-Maria Victoria Eremia, and Gabriel Lucian Radu
MDPI AG
Lately, there has been increased interest in the development of phytochemical alternatives for the prevention and treatment of type 2 diabetes, the alternatives that are able to reduce or prevent glucose absorption by inhibiting digestive enzymes. In this context, this study aims to analyze the inhibitory α-amylase and α-glucosidase activities of Artemisia abrotanum and Symphytum officinale polyphenolic compound-rich extracts obtained by membrane technologies (micro- and ultrafiltration). Polyphenols and flavones content, HPLC-MS polyphenolic compounds profiling, antioxidant activity, and cytotoxic potential of these herbs were determined. Major phenolic acid compounds were chlorogenic acid, ellagic acid, caffeic acid, and rosmarinic acid. The flavone content was higher in the case of A. abrotanum extracts, and the major compounds were rutin and umbelliferone. The polyphenolic-rich extract of A. abrotanum had the highest quantities of polyphenols, 977.75 µg/mL, and flavones, 552.85 µg/mL, as well as a pronounced α-amylase inhibitory activity (IC50 1881.21 ± 1.8 mg/mL), a value close to acarbose inhibitory activity (IC50 1110.25 ± 8.82 mg/mL) that was used as the control for both enzymes. The α-glucosidase inhibitory activity was higher for both herb extracts, more pronounced for S. officinale polyphenolic-rich extract (IC50 291.56 ± 2.1 mg/mL), a value higher than that of acarbose (IC50 372.35 ± 3.2 mg/mL). These plants show potential as a complementary therapy for type 2 diabetes management.
Sandra A. V. Eremia, Camelia Albu, Gabriel L. Radu, and Marian Ion
MDPI AG
In recent years, the wine industry has shown a considerable degree of interest in the occurrence of melatonin in wines. Sample pretreatment may be the most important step in trace analysis. Since wine is a complex matrix and melatonin is present in low amounts (ppb), an adequate extraction technique is required. In this study, the effect of several extraction methods, such as solid phase extraction (SPE), Quick, Easy, Cheap, Effective, Rugged, and Safe extraction (QuEChERS), and dispersive liquid–liquid micro-extraction (DLLME) was studied and the variable parameters that can arise throughout the extraction process were optimized to obtain the best results. A high-performance liquid chromatography with fluorescence detector (HPLC-FL) method was adapted and validated, including measurement uncertainty, for the analysis of melatonin in wines and to assess the efficiency of the extraction yield. After comparing the acquired results, the DLLME method was optimized. Extraction recoveries values ranging from 95 to 104% demonstrated that the approach may be successfully applied for the extraction and concentration (enrichment factor of almost eight) of melatonin in wine samples prior to HPLC-FL analysis. The first report of melatonin levels in Feteasca Neagra wines has been made. The data obtained for Cabernet Sauvignon revealed that the final levels of melatonin in the wines are dependent on the winemaking process.
Emanuel Vamanu, Florentina Gatea, Ionela Avram, Gabriel Lucian Radu, and Sandeep Kumar Singh
MDPI AG
The administration of chokeberry extract in vitro in the GIS1 system was evaluated for the modulation capacity of the dysbiotic pattern resulting from the consumption of stevia. The microbial pattern determined by molecular method, the metabolomic one (fatty acids), the evolution of the antioxidant status, and the cytotoxic effect were determined comparatively for six months. This study presented for the first time that Aronia extract has a strong antimicrobial effect but also a presence of new organic acids that can be used as a biomarker. The functional supplement had the impact of a gradual increase in antioxidant status (DPPH scavenging activity) for up to three months and a subsequent decrease correlated with the reduction of the microbial load (especially for Enterobacteriaceae). The effect on metabolomic activity was specific, with butyric acid being generally unaffected (0.6–0.8 mg/mL) by the antimicrobial effect manifested after three months of administration. The pH was strongly acidic, corresponding to the constant presence of maximum values for acetic and lactic acid. The non-selective elimination of a part of the microbiota could also be correlated with a decrease in metabolomic efficiency. The results in the GIS1 system indicated for the first time that the controlled use of this extract had a pronounced antimicrobial and cytotoxic effect. This has helped to correct the dysbiotic pattern that results after the long-term use of sweeteners based on an increase of 0.2 log UFC/mL for favorable strains.
Maria-Cristina Radulescu, Madalina-Petruta Bucur, Bogdan Bucur, and Gabriel Lucian Radu
The Electrochemical Society
Sensitive and stable electrodes modified with 4-aminothiophenol were developed for heavy metal detection based on coordination bonds between thiol moieties and analyte. The electrodes were modified using diazonium chemistry in one step modification protocol. The presence of 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) in the electrodeposition media avoids the formation of multilayers and improves the performances due to low surface passivation and good electrochemical transfer at the interface with the solution. Electrodeposition of the organic layer on the electrode surface by chronopotentiometry allowed a good control of the electrode modification process, avoids passivation, and leads to reproducible layers with improved characteristics in comparison with modifications carried out by cyclic voltammetry or chronoamperometry. The electrode was able to detect Pb(II) by differential pulse voltammetry with a linear range of 2.5–400 μg l−1 and the detection limit of 1.2 μg l−1 and Cd(II) with the calibration line in the range of 2.5–400 μg l−1 and a detection limit of 1.5 μg l−1. Low interferences were observed and the electrodes were applied for analysis of real samples: fruits pomace and waters.
Madalina-Petruta Bucur, Bogdan Bucur, Elena Bacalum, Victor David, and Gabriel Lucian Radu
Elsevier BV
Gabriela Paun, Elena Neagu, Viorica Parvulescu, Mihai Anastasescu, Simona Petrescu, Camelia Albu, Gheorghe Nechifor, and Gabriel Lucian Radu
MDPI AG
This study presents the preparation of hybrid nanofiltration membranes based on poly(1,4-phenylene ether ether sulfone), polyacrylonitrile, poly(vinyl pyrrolidone), and SBA-15 mesoporous silica. Laser treatment of polymeric solutions to enhance the hydrophilicity and performance of membranes was investigated. The membranes’ structure was characterized using scanning electron (SEM) and atomic force (AFM) microscopy and contact angle measurements. The addition of PAN in the casting solution produced significant changes in the membrane structure, from finger-like porous structures to sponge-like porous structures. Increased PAN concentration in the membrane composition enhanced the hydrophilicity of the membrane surface, which also accounted for the improvement in the antifouling capabilities. The permeation of apple pomace extract and the content of polyphenols and flavonoids were used to evaluate the efficacy of the hybrid membranes created. The results showed that the hybrid nanofiltration membranes based on PPEES/PAN/PVP/SBA-15: 15/5/1/1 and 17/3/1/1 exposed to laser for 5 min present a higher rejection coefficient to total polyphenols (78.6 ± 0.7% and 97.8 ± 0.9%, respectively) and flavonoids (28.7 ± 0.2% and 50.3 ± 0.4%, respectively) and are substantially better than a commercial membrane with MWCO 1000 Da or PPEES-PVP-based membrane.
Alexandra-Gabriela Oancea, Arabela Elena Untea, Catalin Dragomir, and Gabriel Lucian Radu
MDPI AG
Having a complex fatty acid profile, milk is the subject of several oxidation processes that are different to those in other food matrices. Considering this, is important to appreciate the degradation status of milk using rapid and simple methods to quantify the main degradation products. The aim of this study was to adapt a simple and rapid method for determination of milk oxidative stability and to quantify malondialdehyde, one of the lipid oxidation products. Four parameters (trichloroacetic acid concentration—TCA, antioxidant type, incubation time, and thiobarbituric acid—TBA concentration) were modified to establish the best experimental sequence. It was concluded that the relevant results were obtained by precipitating milk proteins using 20% TCA; incubating samples for 90 min with 0.8% TBA, without adding antioxidant; and registering absorbance at three different wavelengths (450, 495, and 532 nm). This method was successfully applied to cow and sheep milk samples and the absorbance values obtained provided information about degradation of fatty acids for both milk types. The Pearson correlation showed a positive relationship between the fatty acid profiles of milk samples and the absorbance values that characterized their oxidation pattern during storage.
Daniel Preda, Iulia Gabriela David, Dana-Elena Popa, Mihaela Buleandra, and Gabriel Lucian Radu
MDPI AG
Antibiotics are antibacterial agents applied in human and veterinary medicine. They are also employed to stimulate the growth of food-producing animals. Despite their benefits, the uncontrolled use of antibiotics results in serious problems, and therefore their concentration levels in different foods as well as in environmental samples were regulated. As a consequence, there is an increasing demand for the development of sensitive and selective analytical tools for antibiotic reliable and rapid detection. These requirements are accomplished by the combination of simple, cost-effective and affordable electroanalytical methods with molecularly imprinted polymers (MIPs) with high recognition specificity, based on their “lock and key” working principle, used to modify the electrode surface, which is the “heart” of any electrochemical device. This review presents a comprehensive overview of MIP-modified carbon-based electrodes developed in recent years for antibiotic detection. The MIP preparation and electrode modification procedures, along with the performance characteristics of sensors and analytical methods, as well as the applications for the antibiotics’ quantification from different matrices (pharmaceutical, biological, food and environmental samples), are discussed. The information provided by this review can inspire researchers to go deeper into the field of MIP-modified sensors and to develop efficient means for reliable antibiotic determination.
Elena-Cornelia Tanasescu, Mihaela-Cristina Lite, Elena Perdum, Lucia Oana Secăreanu, Ovidiu Iordache, Irina-Mariana Sandulache, and Lucian Gabriel Radu
INCDTP - Leather and Footwear Research Institute (ICPI), Bucharest, Romania
Fabric phase sorptive extraction (FPSE) is a new-generation of sample preparation technique that effectively combines representative characteristics of solid-phase microextraction – SPME (equilibrium-based extraction) and solid phase extraction – SPE (exhaustive extraction). FPSE was introduced in 2014 by Kabir A. and Furon K.G. FPSE utilizes a fabric substrate (natural or synthetic such as cotton or polyester) that is chemically coated with a hybrid sorbent (organic-inorganic sol-gel). The entire assembly (fabric substrate coated with the sol-gel polymer) results in a fast and sensitive micro-extraction device. The FPSE development process can be described in 3 main steps: (1) Preparation of the fabric substrate for sol-gel coating, (2) preparation of the sol-solution for coating the substrate, and (3) formation of sol-gel coatings on the fabric substrate. Using this technique can be ensured a faster, cleaner, and with a high concentration of analyte solution. FPSE is a method that can be easily modified and used in different types of applications. For this reason, FPSE is increasingly used in the scientific community dealing with sample pretreatment. By using this technique, promising results have been obtained both for the extraction and determination of certain analytes from environmental samples, as well as from other types of samples, with complex matrices (food and biological samples). This study aims to summarize the existing data on FPSE and to briefly present this innovative method.
Laurentiu Mihai Palade, Constantin Croitoru, Camelia Albu, Gabriel Lucian Radu, and Mona Elena Popa
MDPI AG
This study investigated the potential of using the changes in polyphenol composition of red wine to enable a more comprehensive chemometric differentiation and suitable identification of authentication markers. Based on high performance liquid chromatography-mass spectrometry (HPLC-MS) data collected from Feteasca Neagra, Merlot, and Cabernet Sauvignon finished wines, phenolic profiles of relevant classes were investigated immediately after vinification (Stage 1), after three months (Stage 2) and six months (Stage 3) of storage, respectively. The data were subjected to multivariate analysis, and resulted in an initial vintage differentiation by principal component analysis (PCA), and variety grouping by canonical discriminant analysis (CDA). Based on polyphenol common biosynthesis route and on the PCA correlation matrix, additional descriptors were investigated. We observed that the inclusion of specific compositional ratios into the data matrix allowed for improved sample differentiation. We obtained simultaneous discrimination according to the considered oenological factors (variety, vintage, and geographical origin) as well as the respective clustering applied during the storage period. Subsequently, further discriminatory investigations to assign wine samples to their corresponding classes relied on partial least squares-discriminant analysis (PLS-DA); the classification models confirmed the clustering initially obtained by PCA. The benefits of the presented fingerprinting approach might justify its selection and warrant its potential as an applicable tool with improved authentication capabilities in red wines.
Gabriela Paun, Viorica Parvulescu, Elena Neagu, Camelia Albu, Larisa Ionita, Monica Elisabeta Maxim, Andrei Munteanu, Madalina Ciobanu, and Gabriel Lucian Radu
MDPI AG
The nanofiltration composite membranes were obtained by incorporation of KIT-6 ordered mesoporous silica, before and after its functionalization with amine groups, into polyphenylene-ether-ether-sulfone (PPEES) matrix. The incorporation of silica nanoparticles into PPEES polymer matrix was evidenced by FTIR and UV–VIS spectroscopy. SEM images of the membranes cross-section and their surface topology, evidenced by AFM, showed a low effect of KIT-6 silica nanoparticles loading and functionalization. The performances of the obtained membranes were appraised in permeation of Chaenomeles japonica fruit extracts and the selective separation of phenolic acids and flavonoids. The obtained results proved that the PPEES with functionalized KIT-6 nanofiltration membrane, we have prepared, is suitable for the polyphenolic compound’s concentration from the natural extracts.
Eugenia D. Teodor, Oana Ungureanu, Veronica Moroeanu, and Gabriel L. Radu
Bentham Science Publishers Ltd.
There is an emerging interest in plant polyphenols as dietary ingredients, particularly for digestive disorders and/or as antitumor agents. The plant compounds or extracts continue to be an alternative to drug use, and many studies aim to find natural substances with selective cytotoxicity on abnormal cells. Phenolic compounds, as important secondary metabolites from plants, are intensively studied as a substitute for drugs. In this review, the recent literature data from the past five years about the potential anticancer/antitumor effect of some categories of phenolics such as stilbenes and xanthones extracted from medicinal plants were surveyed. The most important results concerning the effectiveness of these active compounds as antitumor/anticancer agents, isolated compounds or as plant extracts, some bioavailability aspects and their mechanism of action in vitro and in vivo, were considered.
Elena-Cornelia Mitran, Irina-Mariana Sandulache, Cristina-Mihaela Lite, and Lucian Gabriel Radu
Revista de Chimie SRL
In time the environmental conditions could damage textiles (materials/ artifacts) causing the need to develop better non-destructive or at least micro-destructive analysis techniques of the samples. There are ethnographic textile artifacts that were treated in the past with various pesticides, that have not been mentioned in any document. These are often re-treated with chemicals by museum staff as a method of preventing pest infestation. Due to the progressive use of many pesticides, this paper was focused on the detection and quantification of three pesticides: malathion, methoxychlor, and permethrin (cis- and trans- isomers). Gas chromatography is one of the most widely used analytical techniques for characterizing volatile organic compounds and therefore was the analytical method of choice for the present study. Because these analytes are found at trace levels, the detection and quantification limits of analytes are very small and it is necessary to optimize and validate a SIM method - that allows the mass spectrometer to detect specific compounds with high sensitivity. In SIM mode, the instrument is set to collect data at selected masses of interest, thus increasing the accuracy and precision of the quantitative results. The present paper is aimed to develop this type of method with specificity and selectivity, high precision (expressed in terms of repeatability and intermediate accuracy), accuracy, suitable working range and linearity, and high degree of series� homogenity.
Eugenia Dumitra Teodor and Gabriel Lucian Radu
Bentham Science Publishers Ltd.
Background:: Phyto, or plant-derived metal nanoparticles, are an interesting and intensive studied group of green synthesized nanoparticles. In the last decade, numerous medicinal plant extracts were used for the synthesis of stable gold or silver nanoparticles with diverse biological effects, such as antioxidant activity, antimicrobial activity, anti-inflammatory activity, hypoglycemic effect, antitumor activity and catalytic activity. Results:: This review has systematized and discussed information from the last 5 years about the research regarding antitumor/anticancer potential of gold nanoparticles obtained via medicinal plant extracts, with special attention on their selective cytotoxicity on tumor cells and on their mechanism of action, in vitro and in vivo assessments. Conclusion:: Much more in vivo and clinical studies are needed before considering phyto-synthesized gold nanoparticles as significant for future medicine.