Strategic Project - UI 674 - 2014

Funder

Organizational Unit

Publications

Exploring the potential of NTME/GC-MS, in the establishment of urinary volatomic profiles. Lung cancer patients as case study

Publication . Porto-Figueira, Priscilla; Pereira, Jorge; Miekisch, Wolfram; Câmara, José S.

The growing cancer incidence and mortality worldwide claims for the development of novel diagnostic strategies. In this study we aimed to explore the potential of an innovative methodology, based on a needle trap microextraction (NTME), combined with gas chromatography-mass spectrometry (GC-MS), as new approach to isolate and profile urinary volatile organic metabolites (VOMs) from lung cancer (LC) patients and healthy individuals (CTRL). In this context, different experimental parameters with influence of NTME extraction efficiency including, temperature, equilibration time, headspace volume, ionic strength, pH, effects of sample volume and stirring, were investigated and optimized. For the DVB/CarX/Car1000 needle trap device (NTD), the best results were obtained using 40 mL headspace of a 4-mL acidified (pH = 2) urine sample with 20% NaCl and an extraction temperature of 50 °C for 40 min of equilibration time. The stability of the isolated VOMs was investigated up to 72 h after extraction. From the VOMs identified, belonging namely to ketones, sulphur and benzene derivatives, 98 presented a frequency of occurrence above 90%. Data were processed by discriminant analysis, retrieving differentiated clusters for LC and CTRL groups. As far we are aware, this is the first study using NTME/GC-MS to establish urinary volatomic profiles. Preliminary results are very promising, as broad and comprehensive volatile profiles were obtained. Moreover, the extended storage stability of the NTD devices opens new opportunities for sampling other matrices in a wide range of applications.

2018Journal article

Open access

Development of new nanocomposites for waste water cleaning

Publication . Vatansever, Sabriie; Cuniberti, Gianaurelio; Rodrigues, João Manuel Cunha; Licciardello, Nadia

Dyes are one of the most common pollutants in water. In particular, azo dyes are highly toxic, have a complex structure and are particularly hard to degrade because they contain nitrogen nitrogen double bonds. In addition, in waste water differently charged dyes can be present. Removing these pollutants with a single method or material is hard by using traditional treatment techniques. In this thesis, new nanocomposites were prepared by combining Fe3O4/P(NIPAM-co-MAA) polymeric microspheres and different generations of Polyamidoamine (PAMAM) dendrimers. The prepared nanocomposites are able to remove differently charged dyes, including the very resistant azo-dye methyl orange, and can also be recycled thanks to their magnetic properties. Different generations (3rd, 4th and 5th) of PAMAM dendrimers and Fe3O4/P(NIPAM-co-MAA) microspheres have been used in order to synthesize the nanocomposites. The most promising nanocomposites were synthesized by also using a different molar ratio of polymer/dendrimer. All the obtained nanocomposites were tested to adsorb differently charged dyes and, in particular, the positively charged dye basic fuchsin (BF) and the negatively charged azo-dye methyl orange (MO). According to the results, the nanocomposite containing the 5th generation of PAMAM showed the maximum adsorption capacity in the removal of both BF and MO. The adsorption capacity of this nanocomposite towards MO is better than the not grafted polymeric microspheres that can adsorb perfectly BF but cannot adsorb MO. Due to their magnetic properties, the nanocomposites can also be removed by applying an external magnetic field.

2019-10-11Master thesis

Open access

Rapid spectrophotometric methods as a tool to assess the total phenolics and antioxidant potential over grape ripening: a case study of Madeira grapes

Publication . Perestrelo, Rosa; Suilva, Catarina; Silva, Pedro; Câmara, José Sousa

The aim of this study was to improve the knowledge of phenolic content and antioxidant potential during ripening of different grape varieties (Malvasia, Sercial and Tinta Negra) used to produce Madeira wine. Rapid spectrophotometric methods were selected to obtain this information, since these methods could be used as a routine analytical procedure, being easy, simple, rapid, and cost-effective. A significant correlation was observed between total phenolic content and antioxidant capacity for all grape varieties under study, which suggests that phenolics either alone or in combination are responsible for the grapes antioxidant capacity. Our findings showed significant differences (p < 0.05) for phenolic content and antioxidant capacity for all the studied grape varieties. Sercial grapes showed the highest values of phenolics and antioxidant capacity. Moreover, grape ripening stages revealed a significant impact on grapes phenolic content and antioxidant capacity. This information could be used by viticulturists and winemakers to improve and define Vitis vinifera L. grapes harvest management in order to maximize its bioactive potential.

2018Journal article

Restricted access

Exploring the potential of needle trap microextraction combined with chromatographic and statistical data to discriminate different types of cancer based on urinary volatomic biosignature

Publication . Porto-Figueira, Priscilla; Pereira, Jorge A. M.; Câmara, José S.

The worldwide high cancer incidence and mortality demands for more effective and specific diagnostic strategies. In this study, we evaluated the efficiency of an innovative methodology, Needle Trap Microextraction (NTME), combined with gas chromatography-mass spectrometry (GC-MS), for the establishment of the urinary volatomic biosignature from breast (BC), and colon (CC) cancer patients as well as healthy individuals (CTL). To achieve this, 40 mL of the headspace of acidified urine (4 mL, 20% NaCl, pH = 2), equilibrated at 50 °C during 40 min, were loaded through the DVB/Car1000/CarX sorbent inside the NTD, and subjected to a GC-MS analysis. This allowed the identification of 130 VOMs from different chemical families that were further processed using discriminant analysis through the partial least squares method (PLS-DA). Several pathways are over activated in cancer patients, being phenylalanine pathway in BC and limonene and pinene degradation pathway in CC the most relevant. Butanoate metabolism is also highly activated in both cancers, as well as tyrosine metabolism in a lesser extension. In BC the xenobiotics metabolism by cytochrome P450 and fatty acid biosynthesis are also differentially activated. Different clusters corresponding to the groups recruited allowed to define sets of volatile organic metabolites (VOMs fingerprints) that exhibit high classification rates, sensitivity and specificity in the discrimination of the selected cancers. As far as we are aware, this is the first time that NTME is used for isolation urinary volatile metabolites, being the obtained results very promising.

2018Journal article

Restricted access

Volatilomic insight of head and neck cancer via the effects observed on saliva metabolites

Publication . Taware, Ravindra; Taunk, Khushman; Pereira, Jorge A. M.; Shirolkar, Amey; Soneji, Dharmesh; Câmara, José S.; Nagarajaram, H. A.; Rapole, Srikanth

Head and neck cancer (HNC) is a heterogeneous malignant disease with distinct global distribution. Metabolic adaptations of HNC are significantly gaining clinical interests nowadays. Here, we investigated effects of HNC on differential expression of volatile metabolites in human saliva. We applied headspace solid phase microextraction coupled with gas chromatography-mass spectrometry analysis of saliva samples collected from 59 human subjects (HNC - 32, Control - 27). We identified and quantified 48 volatile organic metabolites (VOMs) and observed profound effects of HNC on these metabolites. These effects were VOM specific and significantly differed in the biologically comparable healthy controls. HNC induced changes in salivary VOM composition were well attributed to in vivo metabolic effects. A panel of 15 VOMs with variable importance in projection (VIP) score >1, false discovery rate (FDR) corrected p-value < 0.05 and log2 fold change (log2 FC) value of ≥0.58/≤-0.58 were regarded as discriminatory metabolites of pathophysiological importance. Afterwards, receiver operator characteristic curve (ROC) projected certain VOMs viz., 1,4-dichlorobenzene, 1,2-decanediol, 2,5-bis1,1-dimethylethylphenol and E-3-decen-2-ol with profound metabolic effects of HNC and highest class segregation potential. Moreover, metabolic pathways analysis portrayed several dysregulated pathways in HNC, which enhanced our basic understanding on salivary VOM changes. Our observations could redefine several known/already investigated systemic phenomenons (e.g. biochemical pathways). These findings will inspire further research in this direction and may open unconventional avenues for non-invasive monitoring of HNC and its therapy in the future.

2018Journal article

Open access