Current approaches for the purification of antibody-drug conjugates.

In the past two decades, antibody-drug conjugates have gained increasing attention because they expand the therapeutic index when compared with that of traditional chemotherapies. Antibody-drug conjugates are highly complex structures consisting of antibodies covalently conjugated with small-molecule cytotoxic drugs. The complex structure of antibody-drug conjugates makes chemistry, manufacturing, and control difficult. In contrast to antibody production, distinct purification methods following conjugation of antibodies with drug-linkers are required for the manufacturing. For process development of antibody drug conjugates, the drug-to-antibody ratio, free drug-linkers, and aggregates are critical quality attributes that must be strictly controlled and removed by appropriate purification techniques. In this review, features of various purification methods used to purify antibody drug conjugates are described and evaluated. The future landscape of the antibody-conjugates field is also discussed briefly.

Recent advances in protein chromatography with polymer-grafted media.

The strategy of using polymer-grafted media is effective to create protein chromatography of high capacity and uptake rate, giving rise to an excellent performance in high-throughput protein separation due to its high dynamic binding capacity. Taking the scientific development and technological innovation of protein chromatography as the objective, this review is devoted to an overview of polymer-grafted media reported in the last five years, including their fabrication routes, protein adsorption and chromatography, mechanisms behind the adsorption behaviors, limitations of polymer-grafted media and chromatographic operation strategies. Particular emphasis is placed on the elaboration and discussion on the behaviors of ion-exchange chromatography (IEC) with polymer-grafted media because IEC is the most suitable chromatographic mode for this kind of media. Recent advances in both the theoretical and experimental investigations on polymer-grafted media are discussed by focusing on their implications to the rational design of novel chromatographic media and mobile phase conditions for the development of high-performance protein chromatography. It is concluded that polymer-grafted media are suitable for development of IEC and mixed-mode chromatography with charged and low hydrophobic ligands, but not for hydrophobic interaction chromatography with high hydrophobic ligands and affinity chromatography with ligands that have single binding site on the protein.

Chiral chromatography method screening strategies: Past, present and future.

Method screening is an integral part of chromatographic method development for the separation of racemates. Due to the highly complex retention mechanism of a chiral stationary-phase, it is often difficult, if not impossible, to device predefined method-development steps that can be successfully applied to a wide group of molecules. The standard approach is to evaluate or screen a series of stationary and mobile-phase combinations to increase the chances of detecting a suitable separation condition. Such a process is often the rate-limiting step for high-throughput analyses and purification workflows. To address the problem, several solutions and strategies have been proposed over the years for reduction of net method-screening time. Some of the strategies have been adopted in practice while others remained confined in the literature. The main objective of this review is to revisit, critically discuss and compile the solutions published over the last two decades. We expect that making the diverse set of solutions available in a single document will help assessing the adequacy of existing screening protocols in laboratories conducting chiral separation.

Recent developments in chromatographic purification of biopharmaceuticals.

Over the last several decades, researchers have time and again proposed use of non-chromatographic methods for processing of biotherapeutic products. However, chromatography continues to be the backbone of downstream processing, particularly at process scale. There are many reasons for this, critical ones being the unparalleled scalability, robustness, and selectivity that process chromatography offers over its peers. It is no surprise then that process chromatography has been a topic of major developments in resin matrix, ligand chemistry, modalities, high throughput process development, process modelling, and approaches for control. In this review, we attempt to summarize major developments in the above-mentioned areas. Greater significance has been given to advancements in the last 5 years (2013-2017).

Protein behavior at surfaces: orientation, conformational transitions and transport.

Chromatography is the key technology in protein purification as well as in protein refolding. Taking the scientific development and technological innovation of protein chromatography as the objective, this article is devoted to an overview of protein behavior at chromatographic surfaces, including protein orientation, conformational transitions (unfolding and refolding), and protein transport. Recent advances achieved by using molecular simulations as well as theoretical and experimental investigations are elaborated and discussed with emphasis on their implications to the rational design of novel chromatographic surfaces or materials and mobile phase conditions for the development of high-performance protein chromatography.

New trends in beer flavour compound analysis.

As the beer market is steadily expanding, it is important for the brewing industry to offer consumers a product with the best organoleptic characteristics, flavour being one of the key characteristics of beer. New trends in instrumental methods of beer flavour analysis are described. In addition to successfully applied methods in beer analysis such as chromatography, spectroscopy, nuclear magnetic resonance, mass spectrometry or electronic nose and tongue techniques, among others, sample extraction and preparation such as derivatization or microextraction methods are also reviewed.

The green fields of chromatography.

Researchers are finding that chromatographic separations that use less solvent and stationary phase provide cheaper, more efficient, and more sensitive results. Sarah Webb explores how these changes are leading to the "greening" of chromatography.

Functionalized ceramics for biomedical, biotechnological and environmental applications.

Surface functionalization has become of paramount importance and is considered a fundamental tool for the development and design of countless devices and engineered systems for key technological areas in biomedical, biotechnological and environmental applications. In this review, surface functionalization strategies for alumina, zirconia, titania, silica, iron oxide and calcium phosphate are presented and discussed. These materials have become particularly important concerning the aforementioned applications, being not only of great academic, but also of steadily increasing human and commercial, interest. In this review, special emphasis is given to their use as biomaterials, biosensors, biological targets, drug delivery systems, implants, chromatographic supports for biomolecule purification and analysis, and adsorbents for toxic substances and pollutants. The objective of this review is to provide a broad picture of the enormous possibilities offered by surface functionalization and to identify particular challenges regarding surface analysis and characterization.

Preparative purification of recombinant proteins: current status and future trends.

Advances in fermentation technologies have resulted in the production of increased yields of proteins of economic, biopharmaceutical, and medicinal importance. Consequently, there is an absolute requirement for the development of rapid, cost-effective methodologies which facilitate the purification of such products in the absence of contaminants, such as superfluous proteins and endotoxins. Here, we provide a comprehensive overview of a selection of key purification methodologies currently being applied in both academic and industrial settings and discuss how innovative and effective protocols such as aqueous two-phase partitioning, membrane chromatography, and high-performance tangential flow filtration may be applied independently of or in conjunction with more traditional protocols for downstream processing applications.

Recent developments in the detection of melamine.

In recent years, there were two reported outbreaks of food borne illness associated with melamine. The presence of melamine and its related compounds in milk, feed, and other foods has resulted in the need for reliable methods for the detection and accurate quantification of this class of contaminants. The sample pretreatment for melamine in a complex matrix usually involves a liquid extraction by a polar solvent, followed by a further clean-up with solid phase extraction. Analyses of melamine and related compounds are commonly carried out by liquid or gas chromatographic methods conjugated with mass spectrometry. Other innovative screening methods, which use antibodies, molecularly imprinted polymers, capillary electrophoresis, and gold nanoparticles, are also used to develop assays and biosensors to melamine. However, many of these methods have been hindered by matrix effects, the solubility of melamine-cyanuric acid complex, and background contamination. This article reviews recent developments for detecting melamine and discusses future directions.

Recent advances of chromatography and mass spectrometry in lipidomics.

Lipidomics, as a novel branch of metabolomics, which is aimed at comprehensive analysis of lipids and their biological roles with respect to health and diseases, has attracted increased attention from biological and analytical scientists. As a result of the complexity and diversity of lipids, accurate identification and efficient separation are required for lipidomics analysis. Mass spectrometry (MS) and chromatography have been extensively developed in the past few decades and hold a distinguished position in qualification and separation science. They are powerful and indispensable tools for lipidomics. Herein, we present the recent advancement of MS, chromatography, and their hyphenation technologies in lipidomics.

Impacto de una TAC en inspiración adicional al protocolo convencional de la PET-TAC con 18F-FDG en la detección de nódulos pulmonares de pequeño tamaño / Impact of an additional inspiration CT scan on the conventional protocol of the 18F-FDG PET-CT in the detection of small pulmonary nodes

Objetivo. Determinar el impacto de una TAC en inspiración adicional al protocolo convencional de la PET-TAC con 18F-FDG en la detección de nódulos pulmonares de pequeño tamaño. Método. Hemos estudiado consecutivamente 100 pacientes que presentaban uno o varios nódulos pulmonares radiológicos. A todos los pacientes se les practicó un PET/TAC (Gemini, Philips). Los parámetros de adquisición fueron los mismos para la TAC no inspiratoria/fusión y la TAC en inspiración: 120kV, 25mAs. Resultados. Un total de 188 nódulos fueron detectados en la TAC inspiratoria, con tamaño entre 0,3 y 3cm. Resultados. La TAC no inspiratoria no evidenció 20/188 nódulos (10,6%) con tamaño entre 0,3 y 1cm: correspondiendo a 17 pacientes. La localización más frecuente en la que no se evidenciaron nódulos en la TAC fue en lóbulos inferiores. Resultados. La PET visualizó hipercaptación de 18F-FDG en el 83,9% y el 72% de los nódulos >1cm y entre 0,7 y 1cm, respectivamente. Sin embargo, únicamente el 10,5% de los nódulos <0,7cm mostraron aumento de actividad metabólica. Conclusiones. En pacientes seleccionados, la práctica de una TAC inspiratoria adicional al estudio PET/TAC aumenta de forma significativa la detección de pequeños nódulos pulmonares (10,6%), especialmente de los localizados en lóbulos inferiores, debido a los movimientos respiratorios y puede tener un impacto en el manejo del paciente(AU)

Aim. To determine the impact of an additional inspiration CT scan on the conventional 18F-FDG PET-CT protocol in the detection of small pulmonary nodules. Method. One hundred consecutive patients who presented with one or various nodules were studied. Whole-body PET-CT was performed using Gemini (Philips). CT acquisition parameters were 120Kv/25mAs, the same as those for the transmission/fusion CT (mild expiration) and inspiratory CT. Results. A total of 188 nodules were detected in the inspiratory CT with sizes between 0.3–3cm. Non-inspiratory CT did not show 20/188 nodules (10.6%) with sizes between 0.3–1cm, this corresponding to 17 patients. The most frequent localization of non-detectable nodules in non-inspiratory CT was the lower lobes.18F-FDG uptake was detected by the PET in 83.9% and 72% of nodules with >1cm and between 0.7 and 1cm, respectively. However, only 10.5% of nodules <0.7cm showed increased metabolic activity. Conclusion. In selected patients, inspiratory CT added to conventional PET-CT significantly improves the detection of small nodules (10.6%), especially in those lesions located in the lower lobes, due to respiratory movements, and may have an impact on patient management(AU)

Recent developments in chromatographic fingerprints from herbal products: set-up and data analysis.

The use of chromatographic fingerprints from herbal products where the whole chromatographic profile is applied to evaluate the quality of the investigated product. In this paper, recent developments in the set-up and data analysis of chromatographic fingerprints for herbal products are discussed. First different set-ups for fingerprint development are reviewed. Prior to fingerprint development, a suitable sample preparation, e.g. extraction, should be considered. In a second instance, this review focuses on the data analysis with regards to the different applications of fingerprints. Usually, chemometric data pretreatment is necessary. This is discussed first, followed by a short overview of the data handling techniques used in the two main application areas of herbal fingerprints, i.e. quality assurance and classification or calibration. The quality assurance, which involves the identification and quality control of the herbal products, is reviewed, followed by the use of fingerprints in classification or modelling. The different application areas are illustrated and discussed with several case studies.

Advances in shotgun proteomics and the analysis of membrane proteomes.

The emergence of shotgun proteomics has facilitated the numerous biological discoveries made by proteomic studies. However, comprehensive proteomic analysis remains challenging and shotgun proteomics is a continually changing field. This review details the recent developments in shotgun proteomics and describes emerging technologies that will influence shotgun proteomics going forward. In addition, proteomic studies of integral membrane proteins remain challenging due to the hydrophobic nature in integral membrane proteins and their general low abundance levels. However, there have been many strategies developed for enriching, isolating and separating membrane proteins for proteomic analysis that have moved this field forward. In summary, while shotgun proteomics is a widely used and mature technology, the continued pace of improvements in mass spectrometry and proteomic technology and methods indicate that future studies will have an even greater impact on biological discovery.

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