Scientist in analytical and bioanalytical chemistry. Her research is focused on the development of novel analytical hyphenated methodologies for environmental and bioclinical applications, food and protein chemistry, cultural heritage. Co-author of more than 123 refereed papers in international journals, 3 PCT patents, she has a long time experience in consulting/research projects with SME, teaching, tutoring, training. Currently she is involved in 5 European Projects Life+.
"....and the dust of your wings was lost in the inconscious breath of the wind"
A novel method for the determination of salivary thiocyanate is presented. Thiocyanate was conver... more A novel method for the determination of salivary thiocyanate is presented. Thiocyanate was converted into ethyl thiocyanate by single-step aqueous derivatization based on triethyloxonium tetrafluorobo-rate and measured by gas chromatography-mass spectrometry (15 min runtime). The ethyl thiocyanate derivative is volatile and can be sampled from the headspace. The derivatization chemistry proposed allows for separation of the analyte from saliva matrix whose introduction in the measurement system is avoided. Quantitation of the analyte was obtained by isotope dilution, employing a 13 C-enriched thio-cyanate as internal standard. Technical details and fundamental aspects of derivatization chemistry and calibration strategy are presented. The method was validated by comparison with a standard method based on ion chromatography. The two independent methodologies produced results in agreement within 3%. Also a three level spike recovery test was carried out for validation purpose and quantitative recoveries were attained. The method is fast, simple, safe, and sensitive. Measurement of a 1 mL volume 50 ng/g of thiocyanate standard produced a signal-to-noise ratio of 250 for the analytical peak. This method is therefore suitable for ultra-trace determination of thiocyanate (low part-per-billion range). For the application described the full detection potential of the method was not required and the sample preparation presented has been designed for quantitation of saliva samples containing 1–400 g/g of thiocyanate with a combined standard uncertainty of 2% relative for saliva samples containing 25 g/g of thiocyanate. This method was applied for the determination of thiocyanate in human saliva samples. Crown
Plant hormones play a crucial role in controlling plant growth and development. These groups of n... more Plant hormones play a crucial role in controlling plant growth and development. These groups of naturally occurring substances trigger physiological processes at very low concentrations, which require sensitive techniques for their quantitation. This study reports on the development of a newly synthesized polymer sorbent for the analysis of indole-3-acetic acid (IAA), which is the most important auxin in plants, from complex raw matrices, such as plant extracts. IAA was determined by high-performance liquid chromatography (HPLC) coupled with fluorescence detection (FD). The polymer developed was able to bind about 94% of IAA with a reproducible manner. The release of IAA in methanol was more than 70% for both of them. Non-specific hydrophobic interactions are, likely, the dominant driving force of the binding between IAA and the polymer. This methodology was applied for the determination of IAA in raw lemon leaves. The detection and quantification limits for IAA in real samples were 0.50 ± 0.08 ng/g and 2.64 ± 0.09 ng/g (n = 3, α = 0.05), respectively. As expected , the IAA concentration in uninfected lemon sample was significantly lower respect to the concentration found in infected sample.
A geological study evidenced the presence of thallium (Tl) at concentrations of concern in ground... more A geological study evidenced the presence of thallium (Tl) at concentrations of concern in groundwaters near Valdicastello Carducci (Tuscany, Italy). The source of contamination has been identified in the Tl-bearing pyrite ores occurring in the abandoned mining sites of the area. The strongly acidic internal waters flowing in the mining tunnels can reach exceptional Tl concentrations, up to 9000μg/L. In September 2014 Tl contamination was also found in the tap water distributed in the same area (from 2 to 10μg/L). On October 3, 2014 the local authorities imposed a Do Not Drink order to the population. Here we report the results of the exposure study carried out from October 2014 to October 2015, and aimed at quantifying Tl levels in 150 urine and 318 hair samples from the population of Valdicastello Carducci and Pietrasanta. Thallium was quantified by inductively coupled plasma - mass spectrometry (ICP-MS). Urine and hair were chosen as model matrices indicative of different time periods of exposure (short-term and long-term, respectively). Thallium values found in biological samples were correlated with Tl concentrations found in tap water in the living area of each citizen, and with his/her habits. Thallium concentration range found in hair and urine was 1-498ng/g (values in unexposed subjects 0.1-6ng/g) and 0.046-5.44μg/L (reference value for the European population 0.006μg/L), respectively. Results show that Tl levels in biological samples were significantly associated with residency in zones containing elevated water Tl levels. The kinetics of decay of Tl concentration in urine samples was also investigated. At the best of our knowledge, this is the first study on human contamination by Tl through water involving such a high number of samples.
Despite the considerable number of published studies in the field of S-nitrosothiols (RSNO), the ... more Despite the considerable number of published studies in the field of S-nitrosothiols (RSNO), the determination of these compounds in biological samples still represents an analytical challenge, due to several technical obstacles and often long sample preparation procedures. Other problems derive from the intrinsic lability of RSNO and the absence of certified reference material, analytically validated methods or suitable internal standards. Also, thiols and nitrites are usually present at high concentrations in biological matrices, and all precautions must be adopted in order to prevent artifactual formation of RSNO. Preanalytical steps (sampling, preservation and pre-treatment of samples) are particularly critical for the obtainment of reliable measurements. Three main mechanisms have been identified capable of compromising the assays: metal-catalyzed RSNO decomposition, reduction of the S-NO bond by thiols (transnitrosylation reactions) and enzymatic degradation of S-nitroso-gluta...
... SPECTROSCOPIC CHARACTERIZATION OF QUANTUM DOT-ENHANCED SOLAR CELLS J. Gardner, E. Albers, CG ... more ... SPECTROSCOPIC CHARACTERIZATION OF QUANTUM DOT-ENHANCED SOLAR CELLS J. Gardner, E. Albers, CG Bailey, S. Hubbard, and R ... Sample temperature was varied between 278K and 358K using a variable temperature chuck with measurements taken every 10 ...
ABSTRACT The naturalized dyes (ND) and the traditional acid dyes (ADs) were compared by studying ... more ABSTRACT The naturalized dyes (ND) and the traditional acid dyes (ADs) were compared by studying the different behavior during the leather dyeing process. NDs are glyconjugated compounds synthesized by the covalent union of a dye species with a natural sugar (e.g. lactose) able to confer water-soluble properties to the dye molecule as a whole. The interactions between the dyes and the leather proteins were studied by FT-IR spectroscopy and thermogravimetric (TG) analyses. The protein cross-linking of the dyed leather samples was investigated by studying the 1654/1690 cm−1 peak height ratio and a deconvolution procedure of the amide I peak. The helix secondary structure was the predominant component of the leather proteins of the samples dyed with low concentrations of NDs (2%), while the β-sheets prevailed when leather samples were dyed with the traditional ADs and high concentrations of NDs (>5%). The data were discussed with respect to TG results.
L'S-nitrosilazione e' un processo di comunicazione cellulare ubiquitario nei sistemi biol... more L'S-nitrosilazione e' un processo di comunicazione cellulare ubiquitario nei sistemi biologici. Tuttavia, la ricerca sul signaling richiede metodi analitici per la determinazione delle specie dell'ossido nitrico (RSNOs) sensibili e specifici. La determinazione diretta delle RSNOs (metodi UV ed elettrochimici) e' limitata a concentrazioni micromolari. Approcci alternativi non rivelano RSNOs nella loro forma intatta, ma si basano sulla rivelazione indiretta dei
In a recent study made on cultures of human leukaemic cells (FLG 29.1 cell line) we were able to ... more In a recent study made on cultures of human leukaemic cells (FLG 29.1 cell line) we were able to detect, by IR microspectroscopy, some significant IR spectroscopic variations following differentiation of cells towards osteoclastic-like behavior. The present study was undertaken on the same cell line in order to monitor biochemical structure variations following fusion induced by polyetilenglycole (PEG), using FTIR
A novel method for the determination of salivary thiocyanate is presented. Thiocyanate was conver... more A novel method for the determination of salivary thiocyanate is presented. Thiocyanate was converted into ethyl thiocyanate by single-step aqueous derivatization based on triethyloxonium tetrafluorobo-rate and measured by gas chromatography-mass spectrometry (15 min runtime). The ethyl thiocyanate derivative is volatile and can be sampled from the headspace. The derivatization chemistry proposed allows for separation of the analyte from saliva matrix whose introduction in the measurement system is avoided. Quantitation of the analyte was obtained by isotope dilution, employing a 13 C-enriched thio-cyanate as internal standard. Technical details and fundamental aspects of derivatization chemistry and calibration strategy are presented. The method was validated by comparison with a standard method based on ion chromatography. The two independent methodologies produced results in agreement within 3%. Also a three level spike recovery test was carried out for validation purpose and quantitative recoveries were attained. The method is fast, simple, safe, and sensitive. Measurement of a 1 mL volume 50 ng/g of thiocyanate standard produced a signal-to-noise ratio of 250 for the analytical peak. This method is therefore suitable for ultra-trace determination of thiocyanate (low part-per-billion range). For the application described the full detection potential of the method was not required and the sample preparation presented has been designed for quantitation of saliva samples containing 1–400 g/g of thiocyanate with a combined standard uncertainty of 2% relative for saliva samples containing 25 g/g of thiocyanate. This method was applied for the determination of thiocyanate in human saliva samples. Crown
Plant hormones play a crucial role in controlling plant growth and development. These groups of n... more Plant hormones play a crucial role in controlling plant growth and development. These groups of naturally occurring substances trigger physiological processes at very low concentrations, which require sensitive techniques for their quantitation. This study reports on the development of a newly synthesized polymer sorbent for the analysis of indole-3-acetic acid (IAA), which is the most important auxin in plants, from complex raw matrices, such as plant extracts. IAA was determined by high-performance liquid chromatography (HPLC) coupled with fluorescence detection (FD). The polymer developed was able to bind about 94% of IAA with a reproducible manner. The release of IAA in methanol was more than 70% for both of them. Non-specific hydrophobic interactions are, likely, the dominant driving force of the binding between IAA and the polymer. This methodology was applied for the determination of IAA in raw lemon leaves. The detection and quantification limits for IAA in real samples were 0.50 ± 0.08 ng/g and 2.64 ± 0.09 ng/g (n = 3, α = 0.05), respectively. As expected , the IAA concentration in uninfected lemon sample was significantly lower respect to the concentration found in infected sample.
A geological study evidenced the presence of thallium (Tl) at concentrations of concern in ground... more A geological study evidenced the presence of thallium (Tl) at concentrations of concern in groundwaters near Valdicastello Carducci (Tuscany, Italy). The source of contamination has been identified in the Tl-bearing pyrite ores occurring in the abandoned mining sites of the area. The strongly acidic internal waters flowing in the mining tunnels can reach exceptional Tl concentrations, up to 9000μg/L. In September 2014 Tl contamination was also found in the tap water distributed in the same area (from 2 to 10μg/L). On October 3, 2014 the local authorities imposed a Do Not Drink order to the population. Here we report the results of the exposure study carried out from October 2014 to October 2015, and aimed at quantifying Tl levels in 150 urine and 318 hair samples from the population of Valdicastello Carducci and Pietrasanta. Thallium was quantified by inductively coupled plasma - mass spectrometry (ICP-MS). Urine and hair were chosen as model matrices indicative of different time periods of exposure (short-term and long-term, respectively). Thallium values found in biological samples were correlated with Tl concentrations found in tap water in the living area of each citizen, and with his/her habits. Thallium concentration range found in hair and urine was 1-498ng/g (values in unexposed subjects 0.1-6ng/g) and 0.046-5.44μg/L (reference value for the European population 0.006μg/L), respectively. Results show that Tl levels in biological samples were significantly associated with residency in zones containing elevated water Tl levels. The kinetics of decay of Tl concentration in urine samples was also investigated. At the best of our knowledge, this is the first study on human contamination by Tl through water involving such a high number of samples.
Despite the considerable number of published studies in the field of S-nitrosothiols (RSNO), the ... more Despite the considerable number of published studies in the field of S-nitrosothiols (RSNO), the determination of these compounds in biological samples still represents an analytical challenge, due to several technical obstacles and often long sample preparation procedures. Other problems derive from the intrinsic lability of RSNO and the absence of certified reference material, analytically validated methods or suitable internal standards. Also, thiols and nitrites are usually present at high concentrations in biological matrices, and all precautions must be adopted in order to prevent artifactual formation of RSNO. Preanalytical steps (sampling, preservation and pre-treatment of samples) are particularly critical for the obtainment of reliable measurements. Three main mechanisms have been identified capable of compromising the assays: metal-catalyzed RSNO decomposition, reduction of the S-NO bond by thiols (transnitrosylation reactions) and enzymatic degradation of S-nitroso-gluta...
... SPECTROSCOPIC CHARACTERIZATION OF QUANTUM DOT-ENHANCED SOLAR CELLS J. Gardner, E. Albers, CG ... more ... SPECTROSCOPIC CHARACTERIZATION OF QUANTUM DOT-ENHANCED SOLAR CELLS J. Gardner, E. Albers, CG Bailey, S. Hubbard, and R ... Sample temperature was varied between 278K and 358K using a variable temperature chuck with measurements taken every 10 ...
ABSTRACT The naturalized dyes (ND) and the traditional acid dyes (ADs) were compared by studying ... more ABSTRACT The naturalized dyes (ND) and the traditional acid dyes (ADs) were compared by studying the different behavior during the leather dyeing process. NDs are glyconjugated compounds synthesized by the covalent union of a dye species with a natural sugar (e.g. lactose) able to confer water-soluble properties to the dye molecule as a whole. The interactions between the dyes and the leather proteins were studied by FT-IR spectroscopy and thermogravimetric (TG) analyses. The protein cross-linking of the dyed leather samples was investigated by studying the 1654/1690 cm−1 peak height ratio and a deconvolution procedure of the amide I peak. The helix secondary structure was the predominant component of the leather proteins of the samples dyed with low concentrations of NDs (2%), while the β-sheets prevailed when leather samples were dyed with the traditional ADs and high concentrations of NDs (>5%). The data were discussed with respect to TG results.
L'S-nitrosilazione e' un processo di comunicazione cellulare ubiquitario nei sistemi biol... more L'S-nitrosilazione e' un processo di comunicazione cellulare ubiquitario nei sistemi biologici. Tuttavia, la ricerca sul signaling richiede metodi analitici per la determinazione delle specie dell'ossido nitrico (RSNOs) sensibili e specifici. La determinazione diretta delle RSNOs (metodi UV ed elettrochimici) e' limitata a concentrazioni micromolari. Approcci alternativi non rivelano RSNOs nella loro forma intatta, ma si basano sulla rivelazione indiretta dei
In a recent study made on cultures of human leukaemic cells (FLG 29.1 cell line) we were able to ... more In a recent study made on cultures of human leukaemic cells (FLG 29.1 cell line) we were able to detect, by IR microspectroscopy, some significant IR spectroscopic variations following differentiation of cells towards osteoclastic-like behavior. The present study was undertaken on the same cell line in order to monitor biochemical structure variations following fusion induced by polyetilenglycole (PEG), using FTIR
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Papers by Emilia Bramanti