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1.
Anal Chem ; 90(15): 9006-9015, 2018 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-29943976

RESUMO

Single-use technologies (SUTs) are widely used during biopharmaceutical manufacture as disposable bioreactors or media and buffer storage bags. Despite their advantages, the risk of release of extractable and leachable (E&Ls) substances is considered an important drawback in adopting disposables in the biomanufacturing process. E&Ls may detrimentally affect cell viability or productivity or may persist during purification and present a risk to the patient if remaining in the final drug product. In this study, 34 plastic films from single-use bags (SUBs) for cell cultivation were extracted with selected solvents that represent reasonable worst-case conditions for most typical biomanufacturing applications. SUBs were incubated at small-scale under accelerated-aging conditions that represented standard operational conditions of use. Leachables analysis was performed following dispersive liquid-liquid microextraction (DLLME) for analyte preconcentration and removal of matrix interference. Resulting extracts were characterized by GC-headspace for volatiles, high resolution GC-Orbitrap-MS/MS for semivolatiles, high resolution LC-Orbitrap-MS/MS for nonvolatiles, and ICP-MS for trace elemental analysis. Multivariate statistical analysis of the analytical data revealed significant correlations between the type and concentration of compounds and bags features including brand, manufacturing date and polymer type. The analytical data demonstrates that, over recent years, the nature of E&Ls has been altered due to the implementation of manufacturing changes and new types of polymers and may change further with the future advent of regulations that will limit or ban the use of certain raw materials and additives. The broad E&L database generated herein facilitates toxicological assessments from a biomanufacturing standpoint and provides practical guidelines for confident determination of E&Ls to enable screening and elimination of nonsatisfactory films for single use bioprocessing.


Assuntos
Contaminação de Medicamentos , Embalagem de Medicamentos/métodos , Espectrometria de Massas/métodos , Plásticos/análise , Solventes/análise , Compostos Orgânicos Voláteis/análise , Produtos Biológicos/química , Cromatografia Líquida/instrumentação , Cromatografia Líquida/métodos , Contaminação de Medicamentos/prevenção & controle , Embalagem de Medicamentos/instrumentação , Desenho de Equipamento , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Microextração em Fase Líquida/instrumentação , Microextração em Fase Líquida/métodos , Espectrometria de Massas/instrumentação , Espectrometria de Massas em Tandem/instrumentação , Espectrometria de Massas em Tandem/métodos
2.
Anal Bioanal Chem ; 407(7): 1871-83, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25600687

RESUMO

The high resolution, accurate mass, and fast scanning features of the Orbitrap(TM) mass spectrometer, combined with the separation power of ultrahigh-performance liquid chromatography were applied for the first time to study the metabolic profiles of several organic flame retardants (FRs) present in indoor dust. To mimic real-life exposure, in vitro cultured HepG2 human hepatocyte cell lines were exposed simultaneously to various FRs in an indoor dust extract for 24 h. Target parent FRs, hexabromocyclododecanes (α-, ß-, and γ-HBCDs), tris-2-chloroethyl phosphate (TCEP), tris(1-chloro-2-propyl) phosphate (TCIPP), and tris(1,3-dichloro-2-propyl) phosphate (TDCIPP), were separated in a single run for the first time using alternating positive and negative heated ESI source. Further metabolite separation and identification was achieved using full scan (70,000 full width at half maximum (FWHM)), accurate mass (up to 1 ppm) spectrometry. Structural confirmation was performed via all ion fragmentation (AIF) spectra using the optional higher collisional dissociation (HCD) cell and MS/MS analysis. First insights into human metabolism of HBCDs revealed several hydroxylated and debrominated phase I metabolites, in addition to conjugated phase II glucuronides. Furthermore, various hydroxylated, oxidized, and conjugated metabolites of chlorinated phosphorous FRs were identified, leading to the suggestion of α-oxidation as a significant metabolic pathway for these compounds.


Assuntos
Bromo/metabolismo , Retardadores de Chama/metabolismo , Espectrometria de Massas/métodos , Compostos Organofosforados/metabolismo , Animais , Células Hep G2 , Humanos , Ratos
3.
Talanta ; 219: 121198, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32887108

RESUMO

Single-use technologies are increasingly used in biopharmaceutical manufacturing. Despite their advantages, these plastic assemblies draw concern because they are a potential source of contamination due to extractable and leachable compounds (E&Ls). Characterising E&Ls from such materials is a necessary step in establishing their suitability for use. Therefore, there is an urgent need for sensitive methods to identify and quantitatively assess compounds in plastic materials. Accelerated solvent extraction (ASE) is a powerful technique that can be reliably used for this purpose. In this study, ASE followed by liquid chromatography and Orbitrap-based High Resolution Accurate Mass (HRAM) mass analysis was found to be an efficient and versatile method for the determination of additives in different multilayer polymer systems from single-use bags. ASE optimisation was performed using a design of experiments approach. The type of solvent, temperature, swelling agent addition, static time and number of cycles were the selected variables. Optimum conditions were dependent on the type of plastic film. Ethyl acetate and cyclohexane were selected individually as optimum solvents. Optimum temperatures were 90-100 °C. Pressure was set at 1500 psi and extraction time was 30 min in 2 cycles. Swelling agent addition was necessary with polar extraction solvents. More than 100 additives and degradation products were confidently identified by HRAM MS. Correlations between the type and levels of identified additives and the type of polymer system were established. In addition, degradation behaviour and pathways for some additives can be addressed.


Assuntos
Polímeros , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Espectrometria de Massas , Solventes
4.
Talanta ; 63(5): 1147-55, 2004 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-18969544

RESUMO

Established and comprehensively validated methodology for the analysis of PCDDs, PCDFs and polychlorinated biphenyls (PCBs) in food, animal feed and other matrices is presented. The method achieves the analytical standards of EU protocols (2002/69/EC and 2002/70/EC) that are used to determine the compliance of food and animal feed to maximum permissible levels of chlorinated dioxins in these commodities. The methodology provides WHO-TEQ data for dioxins and PCBs as well as individual concentrations for toxic PCDD/F congeners and >50 commonly occurring PCBs. In addition, the methodology allows the simultaneous determination of individual polybrominated diphenylether (PBDE) congeners. A wide range of (13)Carbon -labelled surrogates allow accurate internal standardisation, and measurements are carried out using high resolution GC coupled to high resolution mass spectrometry except for mono-, tetra, ortho-substituted PCBs where unit resolution mass spectrometry can be used instead. Evidence of internal as well as external validation through the frequent use of reference materials, and successful participation in international inter-comparison exercises over many years is presented. A large number of different food types have been analysed for dioxins and PCBs using this methodology over several years and typical congener profiles for various food matrices are discussed.

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