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1.
Chimia (Aarau) ; 72(3): 146-150, 2018 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-29631666

RESUMEN

The pharmaceutical industry is one of the most regulated industries in Switzerland. Though the concept of good manufacturing practises (GMP) was implemented for chemical production in the early 1990s, the rules and regulations for our industry are in constant evolution. In this article we will highlight the impact of these changes to the industry using three recent guideline up-dates as examples: the implementation of ICH Q3D 'Guideline for elemental impurities', the EU-GMP Guideline Part III Chapter 'Guideline on setting health based exposure limits for use in risk identification in the manufacture of different medicinal products in shared facilities' from 01. June 2015, and the new guidelines to data integrity such as 'PIC/S 041-1 Good Practices for Data Management and Integrity in regulated GMP/GDP environments'. These examples show how scientific approaches help to modernize the control strategies for our products and increase product quality for a better patient safety. The requirements of data integrity regulations are also of interest to industries and universities not working under GxP requirements as they also support the business to improve data quality (traceability) for patent applications, and reduce risk of data falsification.


Asunto(s)
Contaminación de Medicamentos/legislación & jurisprudencia , Industria Farmacéutica/legislación & jurisprudencia , Legislación de Medicamentos/tendencias , Contaminación de Medicamentos/prevención & control , Industria Farmacéutica/organización & administración , Industria Farmacéutica/normas , Regulación Gubernamental , Guías como Asunto , Control de Calidad , Suiza
2.
Rapid Commun Mass Spectrom ; 17(20): 2303-9, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14558130

RESUMEN

In this work, a high repetition rate laser matrix-assisted laser desorption/ionization (MALDI) source is studied on a quadrupole-time-of-flight (QqTOF) and a triple quadrupole (QqQ) mass spectrometer for rapid quantification of small pharmaceutical drugs. The high repetition rate laser allows an up to 100-fold higher pulse frequency as compared with regular MALDI lasers, resulting in much larger sample throughput and number of accumulated spectra. This increases the reproducibility of signal intensities considerably, with average values being around 5% relative standard deviation after taking into account the area ratio of the analyte to an internal standard. Experiments were conducted in MS/MS mode to circumvent the large chemical background due to MALDI matrix ions in the low mass range. The dynamic range of calibration curves on the QqTOF mass spectrometer extended over at least two orders of magnitude, whereas on the QqQ it extended over at least three orders of magnitude. Detection limits ranged from 60-400 pg/microL on the QqTOF and from 6-70 pg/microL on the QqQ for a series of benzodiazepines. The benzodiazepine content of commercial pill formulations was quantified, and less than 5% error was obtained between the present method and the manufacturer's certified values. Furthermore, a high sample throughput was achieved with this method, so that a single MALDI spot could be quantitatively scanned in as little as 15 s, and an entire 96-well MALDI plate in 24 min.


Asunto(s)
Benzodiazepinas/análisis , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Calibración , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrometría de Masa por Ionización de Electrospray , Comprimidos/química
3.
Rapid Commun Mass Spectrom ; 17(21): 2439-49, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14587091

RESUMEN

Spot size reduction and increased detection sensitivity in matrix-assisted laser desorption/ionisation (MALDI) of small molecules are accomplished by using an inexpensive and removable hydrophobic coating for MALDI targets, based on 3M Scotch Gard surface treatment. Several variations in sample preparation were explored, such as surface coating technique, identity of the matrix, solvent composition, and the type of metal support plate used. These were investigated on both uncoated and coated surfaces and their impact on spot size, crystal coverage, and sensitivity is presented here. Additionally, crystallisation behaviour obtained on coated plates is compared with that on uncoated plates using scanning electron microscope analysis. To demonstrate the potential of the new coating technique, erythromycin A and valinomycin are studied to determine the increase in detection sensitivity of coated plates in comparison to uncoated plates, and to reveal the suitability of the plates for application in combined high-performance liquid chromatography/MALDI (HPLC/MALDI), where widely varying solvent compositions and droplet volumes are observed. It is shown that enhancements in detection sensitivities correlate very well with the achieved spot size reduction. The versatility of the coated plates is also exhibited by the ease of removing the surface layer, after which the plates can be rigorously cleaned without worry about damaging the hydrophobic surface, followed by a quick reapplication of new hydrophobic coating material. This makes the non-polar coating superior to more expensive commercial hydrophobic-coated targets, which are much more delicate to clean. Furthermore, cleaning and reapplication eliminate potential carry-over effects and the easy application procedure also makes the fabrication of inexpensive, disposable MALDI targets readily possible.


Asunto(s)
Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/economía , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/instrumentación , Eritromicina/análisis , Interacciones Hidrofóbicas e Hidrofílicas , Sensibilidad y Especificidad , Solventes/química , Valinomicina/análisis
4.
Rapid Commun Mass Spectrom ; 17(18): 2153-9, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12955747

RESUMEN

Azaspiracids are neurotoxins produced by marine algae that have been detected in harvested mussels since 1995. They pose a significant threat to human health through the consumption of contaminated shellfish, and negatively impact the economy of areas where shellfish are harvested and processed. Regulatory agencies are beginning to advocate instrumental assays over traditional mouse bioassay methods. The development and validation of an assay method for AZA 1, the predominant azaspiracid toxin, and the production of a calibration standard and reference material will therefore be vital for quality control in monitoring laboratories worldwide. This report demonstrates a rapid and reproducible liquid chromatography/mass spectrometry (LC/MS) method for separation of all twelve known azaspiracids. Using a triple-quadrupole mass spectrometer, ultra-high sensitivity was obtained at the low-femtogram level injected on-column. At the same time, a linear response of three orders of magnitude was observed. We compared the results with those measured on an ion-trap mass spectrometer. The triple-quadrupole instrument was more sensitive, reliable and reproducible than the ion-trap instrument. The detection limit obtained on the ion-trap mass spectrometer was ten times higher than that obtained on the triple quadrupole. During the study, a new azaspiracid analog (AZA 7c) was discovered.


Asunto(s)
Toxinas Marinas/análisis , Espectrometría de Masas/métodos , Compuestos de Espiro/análisis , Animales , Bivalvos/química , Calibración , Cromatografía Líquida de Alta Presión/métodos , Eucariontes/química , Toxinas Marinas/química , Control de Calidad , Estándares de Referencia , Reproducibilidad de los Resultados , Compuestos de Espiro/química
6.
Anal Bioanal Chem ; 376(6): 773-9, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12802557

RESUMEN

This study describes the application of a novel, reactive matrix for the mass spectral analysis of steroids by capillary-high performance liquid chromatography (capillary-HPLC) coupled to matrix-assisted laser desorption/ionization (MALDI). The mass spectral analysis of steroids was accomplished after fully automated peak deposition of chromatographic peaks onto MALDI targets. The seven corticosteroids used as test compounds were: triamcinolone, prednisone, cortisone, fludrocortisone, dexamethasone, deoxycorticosterone, and budesonide. They were separated using a PepMap C(18) (3 microm particle size, 100 A pore width) column at five different concentration levels of 25, 15, 7.5, 2.5 and 1 ng/microL, and the peaks were detected at a wavelength of 237 nm. The column effluent was mixed with 2,4-dinitrophenylhydrazine (DNPH) directly following the UV detector. The chromatographic peaks were then deposited onto the MALDI target with a robotic micro-fraction collector triggered by the UV detector signals. A special hydrophobic surface coating allowed the deposition of up to 4 microL (up to 90 % of the chromatographic peak volume) onto one sample spot. The compounds were then identified by MALDI mass spectrometry. Depending on the nature of the analyte, radical cations ([M](+.)) and sodium adduct ions ([M+Na](+)) of the steroids as well as protonated steroid-dinitrophenylhydrazone derivatives ([M(D)+H](+)) were detected in positive ion mode. The detection limits were between 0.5 and 15 ng injected with capillary-HPLC-MALDI-TOF-MS and between 0.3 and 3 ng on target with MALDI-TOF when deposited manually.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Electroforesis Capilar/métodos , Preparaciones Farmacéuticas/análisis , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Cortisona/análisis , Cortisona/química , Desoxicorticosterona/análisis , Desoxicorticosterona/química , Dexametasona/análisis , Dexametasona/química , Fludrocortisona/análisis , Fludrocortisona/química , Estructura Molecular , Tamaño de la Partícula , Preparaciones Farmacéuticas/química , Prednisona/análisis , Prednisona/química , Triamcinolona/análisis , Triamcinolona/química
7.
Rapid Commun Mass Spectrom ; 16(24): 2298-305, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12478575

RESUMEN

In this study, the performance of monolithic columns was evaluated for ultrafast liquid chromatography/mass spectrometry (LC/MS) analyses and for high-resolution separations of several azaspiracid biotoxin analogs. Because of their high permeability, monolithic columns offer a number of advantages over conventional packed columns; viz., very low backpressures and relatively flat van Deemter curves at high flow rates. That is, very high flow rates can be used for ultrafast analyses or, by using longer than normal columns, high-resolution separations are possible. In a series of experiments, we varied the mobile phase flow rates between 1 and 8 mL/min, and studied their impact on chromatographic parameters such as retention time, resolution, number of plates and pressure. The chromatographic run times could be reduced to ca. 30 s without a significant change in the separation efficiency. A signal intensity comparison revealed interesting differences between atmospheric-pressure chemical ionization (APCI) and electrospray ionization (ESI) in their flow-rate dependency. An explanation with respect to the behavior as of a mass-flow or a concentration-dependent device is given in the paper. Additionally, the column length was varied between 10 and 70 cm. As a result, the number of theoretical plates increased substantially. In the example shown in the report, an increase from 13 000 plates for a 10-cm column to 80 000 for a 70-cm column is demonstrated. In addition, the potential of the monolithic columns for high-resolution LC/MS separations is shown for a complex biotoxin mixture, which was separated on a 40-cm-long column.


Asunto(s)
Cromatografía Liquida/instrumentación , Cromatografía Liquida/métodos , Toxinas Marinas/química , Espectrometría de Masas/instrumentación , Espectrometría de Masas/métodos , Compuestos de Espiro/química , Animales , Bivalvos/química , Estructura Molecular , Sensibilidad y Especificidad , Extractos de Tejidos/química
8.
Rapid Commun Mass Spectrom ; 16(24): 2306-16, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12478576

RESUMEN

In this report, the mass spectral analysis of azaspiracid biotoxins is described. Specifically, the collision-induced dissociation (CID) behavior and differences between CID spectra obtained on a triple-quadrupole, a quadrupole time-of-flight, and an ion-trap mass spectrometer are addressed here. The CID spectra obtained on the triple-quadrupole mass spectrometer allowed the classification of the major product ions of the five investigated compounds (AZA 1-5) into five distinct fragment ion groups, according to the backbone cleavage positions. Although the identification of unknown azaspiracids was difficult based on CID alone, the spectra provided sufficient structural information to allow confirmation of known azaspiracids in marine samples. Furthermore, we were able to detect two new azaspiracid analogs (AZA 1b and 6) in our samples and provide a preliminary structural analysis. The proposed dissociation pathways under tandem mass spectrometry (MS/MS) conditions were confirmed by a comparison with accurate mass data from electrospray quadrupole time-of-flight MS/MS experiments. Regular sequential MS(n) analysis on an ion-trap mass spectrometer was more restricted in comparison to the triple-quadrupole mass spectrometer, because the azaspiracids underwent multiple [M + H - nH(2)O](+) (n = 1-6) losses from the precursor ion under CID. Thus, the structural information obtained from MS(n) experiments was somewhat limited. To overcome this limitation, we developed a wide-range excitation technique using a 180-u window that provided results comparable to the triple-quadrupole instrument. To demonstrate the potential of the method, we applied it to the analysis of degraded azaspiracids from mussel tissue extracts.


Asunto(s)
Bivalvos/química , Toxinas Marinas/química , Espectrometría de Masas/métodos , Compuestos de Espiro/química , Animales , Estructura Molecular , Extractos de Tejidos/química
9.
Anal Bioanal Chem ; 372(5-6): 622-9, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11941430

RESUMEN

The suitability of HPLC combined with ion-trap mass spectrometry was studied for the determination of carbonyl-2,4-dintrophenylhydrazones in ambient air. MS quantification was based on two internal standards and atmospheric pressure chemical ionization in the negative-ion mode. Limits of detection for air samples of 750 L in the full-scan mode varied between 1 and 15 ng x m(-3) expressed as carbonyl. Limits of quantification were approximately a factor of three higher. This is sufficient for background regions. For sample volumes of 750 L air the instrument response was linear from 10 ng x m(-3) to 800 microg x m(-3) for carbonyls and from 3 ng x m(-3) to 250 ng x m(-3) for dicarbonyls. Besides complete method validation, quantitative results for six air samples from four background sampling sites in North and Central Europe were compared with those obtained by use of HPLC-UV. Thirty-six carbonyl compounds could be identified and twenty-four were quantified. Values for major compounds, i.e. those present at levels well above the UV detection limits (9 to 18 ng x m(-3)), deviated by less than 20%.

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