Development of a solventless method for the pesticides analysis.

This paper represents the results of a case study investigating the development of a novel, simple, cost-effective, solventless and sensitive chromatographic method for the determination of volatile pesticides in aqueous samples by an electrothermally prepared pencil graphite (PG). In this study, PG were conditioned by passing a suitable direct current to activate PG by Joule effect. Conditioned PG was used for the extraction of Chlorpyrifos (CP), which is used as case study. The method was also found successful in the determination of CP in real water samples, providing acceptable recovery values (82-111%).

Development of a new needle trap-based method for the determination of some volatile organic compounds in the indoor environment.

Volatile Organic Compounds (VOCs) are a large group of chemicals mostly found in indoor environments such as homes and workplaces. Long term exposure to certain VOCs can cause symptoms in some individuals and therefore, monitoring and controlling air quality can help better manage chronic respiratory diseases. In this study, we aimed to develop an easy-to-use, economical, in house needle trap-based methodology to detect certain VOCs to be used for public and occupational health. For this purpose, a multi-bed (packed with PDMS/Carbopack-X/Carboxen-1000) needle trap device (NTD) was utilized for sampling, enrichment, and injection of the VOCs into the gas chromatography. The performance of the developed method was investigated for the analysis of the group known as BTEX (benzene, toluene, ethylbenzene and xylene). Operational and instrumental parameters such as sampling flow rate and relative humidity, desorption time and temperature were optimized, and the analytical figures of merit of the proposed method have indicated that very low levels of BTEX in air samples can be easily determined by this new method. Overall results have shown that multi-bed NTD offers a high sensitive procedure for sampling and analysis of BTEX in concentration range of 0.002-0.298 mg/m3 in indoor air.

Concordance in molecular genetic analysis of tumour tissue, plasma, and exhaled breath condensate samples from lung cancer patients.

AIM: Lung adenocarcinoma is characterized by poor prognosis and short survival rates. Therefore, tools to identify the tumoural molecular structure and guide effective diagnosis and therapy decisions are essential. Surgical biopsies are highly invasive and not conducive for patient follow-up. To better understand disease prognosis, novel non-invasive analytic methods are needed. The aim of the present study is to identify the genetic mutations in formalin-fixed paraffin-embedded (FFPE) tissue, plasma, and exhaled breath condensate (EBC) samples by next-generation sequencing and evaluate their utility in the diagnosis and follow-up of patients with lung adenocarcinoma. METHOD: FFPE, plasma, and EBC samples were collected from 12 lung adenocarcinoma patients before treatment. DNA was extracted from the specimens using an Invitrogen PureLink Genomic DNA Kit according to the manufacturer's instructions. Amplicon-based sequencing was performed using Ion AmpliSeq Colon and Lung Cancer Research Panel v2. RESULTS: Genetic alterations were detected in all FFPE, plasma, and EBC specimens. The mutations in PIK3CA, MET, PTEN, SMAD4, and FGFR2 genes were highly correlated in six patients. Somatic and novel mutations detected in tissue and EBC samples were highly correlated in one additional patient. The EGFR p.L858R and KRAS p.G12C driver mutations were found in both the FFPE tissue specimens and the corresponding EBC samples of the lung adenocarcinoma patients. CONCLUSION: The driver mutations were detected in EBC samples from lung adenocarcinoma patients. The analysis of EBC samples represents a promising non-invasive method to detect mutations in lung cancer and guide diagnosis and follow-up.