We have a series of "Shodex Technical Articles" available for your reference.
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No.	Title
1	Analysis of Aggregates and Additives in Antibody Drugs
	This article introduces analysis of antibody drug dimers and aggregates using a silica-based aqueous size exclusion chromatography (SEC) column, Shodex PROTEIN LW-803, and rapid LC/MS analysis of polysorbate using a polymer-based reversed-phase column, Shodex ODP2 HP-2D. It is known that antibody drugs may aggregate to form dimers and other larger aggregates during manufacturing process and/or during storage period. There are concerns that those larger aggregates may become immunogenic conjugates and lead to cause side effects, and thus monitoring of such aggregates is an important quality control (QC) criterion. Additionally, during the production of antibody drugs, small amounts of surfactants (e.g., polysorbate (Tween)) may be added to solubilize or stabilize IgG. Therefore, management of surfactants’ concentrations is also an important QC criterion.
2	Simultaneous LC/MS Analysis of Glyphosate and Its Related Compound
	This article introduces a highly-sensitive simultaneous LC/MS/MS analysis of glyphosate and its related compounds without the use of pre-column derivatization nor ion-pair reagents. The column used was Shodex HILICpak VT-50 2D, a Hydrophilic Interaction Liquid Chromatography (HILIC) column modified with quaternary ammonium functional group. Organophosphate herbicides such as glyphosate and glufosinate are globally used. Most countries have regulations for organophosphate herbicide usage due to concerns on their toxicity to humans. Since those compounds are highly hydrophilic, pre-column derivertization or ion-pair reagents are required if analyzed with a reversed phase column.
3	LC/MS Analysis of Various Hydrophilic Compounds Using HILIC Mode and Alkaline Eluent
	This article introduces simultaneous LC/ MS analyses of saccharides, organic acids, and amino acids using a semi-micro size Shodex HILICpak VG-50 2D column. Components of pharmaceutical and food products often include high polar compounds. Those compounds are hardly retained under reversed phase mode. To overcome the problem, precolumn derivertization or ion-pair reagents are often used. Shodex HILICpak VG-50 series is a set of polymer-based amino columns which effectively separate various saccharides. The packing material consists of a polyvinyl alcohol base with a hydrophilic functional group, a modified tertiary amine. Column bleeding is rarely found with this column. Another advantage of this column is that it can be used under alkaline conditions.
4	LC/MS Analysis of Oligonucleotides
	This articles introduces LC/MS analysis of oligonucleotide using a semi-micro size Shodex HILICpak VN-50 2D column. HILICpak VN-50 2D is packed with multi-porous polyvinyl alcohol polymers modified with diol functional groups. Oligonucleotide therapeutics have high expectations in the areas of genetic and metabolic treatments, but also for anti-cancer drugs and vaccines of various diseases. The development and quality control of the oligonucleotide therapeutics often require highly selective and sensitive analytical methods. The method with an LC/MS system is one of them. The most often used method for the oligonucleotide analyses have been reversed phase chromatography with the use of an ion-pair reagent. The application developed here did not require an ion-pair reagent. Instead, a gradient elution method employing a volatile basic solvent and acetonitrile was used.
5	LC/MS Analysis of Various Low-Molecular Weight Cationic Compounds Using HILIC Mode
	This article introduces simply and highly sensitive LC/MS analyses of various low-molecular weight cationic compounds using a semi-micro size Shodex HILICpak VC-50 2D column. HILICpak VC-50 2D is packed with multi-porous polyvinyl alcohol polymers modified with carboxyl functional groups. The compounds analyzed were choline and acetylcholine, neurotransmitters, oral antidiabetic drugs, salacinol related compounds, and amminoglycoside antibiotics. Most low-molecular weight cationic compounds are hydrophilic and hardly retained under reversed phase mode, and thus pre-column derivertization or ion-pair reagents are often required. However, the application developed here did not require them.
7	Analysis of Various Oligosaccharides Using HILIC Mode
	This article introduces analyses of various oligosaccharides including nonionic oligosaccharides (dextrin, chitooligosaccharides and xylooligosaccharides),  cationic oligosaccharides (chitosan oligosaccharides), and anionic oligosaccharides (oligogalacturonic acids) using Shodex HILICpak VN-50 4D. An oligosaccharide is a polysaccharide containing at least two monosaccharides bonded by glycosidic linkages. It is known that the oligosaccharides are utilized by gut bacteria, and increasing the bacteria number is beneficial for the digestive health. Thus, functionality benefits of the oligosaccharides have been focused in some industries. Size Exclusion Chromatography (SEC) is one of the known methods for oligosaccharide analysis. On the other hand, Hydrophilic Interaction Liquid Chromatography (HILIC) can provide better separation for the larger oligomers than the SEC mode does. Thus, the methods using the HILIC mode are also commonly used these days. HILICpak VN-50 series columns are packed with multi-porous polyvinyl alcohol polymers modified with diol functional groups. The columns are durable to the high pH conditions, and feasible for analyzing various oligosaccharides since the modified diol functional group is nonionic.
8	Ultra-Rapid Analysis of High Molecular Weight Compounds Using SEC Mode
	This article introduces Shodex GPC HK series columns with their characteristics and applications. Size Exclusion Chromatography (SEC) is one of the separation modes where analytes are separated based on their sizes. The technique is frequently used to analyze high molecular weight compounds, as SEC mode is effective evaluating their physical properties. However, the longer analysis time of SEC is a drawback. Consequently, the eluent consumption of a SEC analysis increases. Since organic eluents used for Gel Permeation Chromatography (GPC) are expensive and cause environmental concerns, the use of organic solvents is a GPC related problem. Therefore, we have worked on the development of novel, ultra-rapid analysis GPC columns. This newly developed GPC HK series columns successfully reduced the analysis time and the eluent consumption.
9	Ultra-Rapid Analysis of Proteins by Cation Exchange Chromatography
	This article introduces Shodex IEC SP-FT 4A with their characteristics and applications. HPLC takes an important role in pharmaceutical and biotech industry for the analysis of biological components such as proteins, peptides, and nucleic acids. Since biological components often carry ionic charges, ion-exchange mode chromatography is an effective method for separating those components. IEC SP-FT 4A is a cation exchange chromatography column, and an improved version of a conventional rapid analysis column. The analysis time of IEC SP-FT 4A is one-third of our conventional column, and this benefit helps a large number of samples to be analyzed at once.
10	Analysis of Functional Sugars in Foods Using HILIC Mode
	This article introduces analysis of functional sugars in foods using Shodex HILICpak VG-50 4E including sample preparation methods for actual food products. Recently, the effects of functional sugars in foods are gaining scientists’ interests, and thus their analytical methods are called for. HILICpak VG-50 series is a set of polymer-based amino columns which effectively separate various saccharides and hydrophilic compounds. The packing material consists of a polyvinyl alcohol base with a hydrophilic functional group, a modified tertiary amine. With some columns, reducing sugars form a Schiff base with the packing material and are retained in the column. This does not occur with the HILICpak VG-50 series columns, leading to the series’ ability to achieve a high recovery rate. Their other advantages include a very little column bleeding and that they can be used under alkaline conditions.
11	HPLC Analysis of Antidiabetic Drugs
	This article introduces analyses of four antidiabetic drugs using Shodex columns: such as an oral antidiabetic drug (metformin), a conventional antidiabetic drug (insulin), and type 2 diabetes drugs (liraglutide and exenatide). Antidiabetic drugs may contain peptides, sugars, and low-molecular weight compounds of different properties. This makes it difficult for an HPLC method to simultaneously analyze all components. Thus, analysis of each component groups require a specific method with an appropriate column and optimized analytical conditions.
12	Simultaneous LC/MS Analyses of Phosphorylated Saccharides
	This article introduces simple and highly sensitive LC/MS analyses of various phosphorylated saccharides using Shodex HILICpak series columns. Phosphorylated saccharides take important roles as intermediates in various metabolic pathways of animals. High sensitive analysis of phosphorylated saccharides in vivo is important for understanding the biological phenomena and early detection and treatment of the related diseases. However, phosphorylated saccharides generally have low UV absorbance, and thus high-sensitive detection of them using conventional detectors is difficult. Additionally, phosphorylated saccharides are highly hydrophilic, so pre-column derivertization or ion-pair reagents are often used in their reversed phase mode analysis. However, the application developed here did not require them.
13	GPC/MS Analysis of Polymer Additives
	This article introduces highly sensitive and selective rapid MS analyses of various polymer additives using Shodex GPC HK-400 series columns. Polymers contain various additives for the additional functionality and stabilization of the product. Analysis of such additives is important for the quality control purposes in the polymer production. Those additives are typically analyzed by liquid chromatography and gas chromatography after pretreating the sample by extraction and concentration. The treatment steps are often complex and time consuming. On the other hand, by using the gel permeation chromatography (GPC), a polymer sample dissolved in an appropriate solvent can directly be analyzed. It separates the additives from polymers, and thus a simple and rapid detection can be expected.
14	Analysis of Functional Ingredients in Dietary Supplements
	This article introduces analyses of functional food ingredients in commercial dietary supplement. In April 2015, Japan started the “Foods with Functional Claims (FFC)” system. FFC product producers obtain the FFC by submitting necessary documents to the Consumer Affairs Agency. The submission does not require any national examination to prove ingredient’s safety nor functionality. This FFC market is keep expanding. The number of the submitted FFC is more than the approved “Food for Specified Health Uses (FOSHU)”, which requires governmental approval before they can qualify for labeling.
15	Purification and SEC/MS Analysis of Norovirus Virus-Like Particles
	This article introduces the effectiveness of Size Exclusion Chromatography (SEC) for the analysis of bionanoparticles. Applied researches on “bionanoparticles” are rapidly expanding in the fields of gene therapy drugs, virus vector, new vaccine, and drug delivery etc. Virus-like particles (VLPs) are typical bionanoparticles, and R&D for its commercialization especially for vaccine is in progress. Due to their complex structures and distinct sizes, production and quality evaluation of their biological processes require integrated and multifaceted analytical techniques, even more than that of conventional biopharmaceutical compounds. As a proof of concept, method development for a chromatographic purification of norovirus cell surface layer binding protein originated VLP (NVLP) is discussed. This article also includes the evaluation of an effective method development using an SEC column with different analytical devices and a summary of how to select a suitable column for the monitoring of purification procedures.
16	Evaluating the Freshness of Fish Flesh Using the K Value
	This article introduces analysis of six ATP related substances in fish flesh for the calculation of K value using Shodex Asahipak GS-320 HQ. The K value is an index for estimating the freshness of fish flesh. The amount of adenosine 5’-triphosphate (ATP) in fish flesh is calculated from a method developed in the 1950s. Since endogenous enzymes degrade ATP in dead seafoods rapidly, the K value can be a quantitative measurement of seafoods’ freshness. Shodex Asahipak GS-320 HQ is a multimode column that provides combinations of several separation modes such as size exclusion, reversed phase, and ion exchange modes.
17	Rapid Analysis of Sugars, Organic Acids, and Alcohols
	This article introduces analysis of  bioethanol by-products using Shodex SUGAR SH1011 8C. In bioethanol production, it is extremely important to constantly check the progress of ethanol fermentation. Especially, there are seven main target analytes: maltooligosaccharide, glucose, ethanol, lactic acid, acetic acid, and glycerol. SUGAR SH1011 8C is a 10-cm rapid analysis column filled with rigid styrene-divinylbenzene copolymer base material. The strong cation exchange gel works to provide a mixed mode of size exclusion and ion exclusion chromatography, which is suitable for a simultaneous analysis of various sugars and organic acids. The analysis time of SUGAR SH1011 8C is one thirds of our regular 30-cm analysis column, SUGAR SH1011.
18	Analysis of Functional Ingredients (Anit-Obesity Agents) in Beverages and Foods
	This article introduces analyses of functional food ingredients, especially focusing on anti-obesity agents in commercial beverages and foods. In April 2015, Japan started the “Foods with Functional Claims (FFC)” system. FFC product producers obtain the FFC by submitting necessary documents to the Consumer Affairs Agency. The submission does not require any national examination to prove ingredient’s safety nor functionality. The number of the submitted FFC is rapidly increasing and the market is keep expanding.
19	LC/MS Analysis of Various Oligonucleic Acids with/without Modifications
	This article introduces LC/MS analyses of modified oligonucleotides such as phosphorothioated oligonucleic acids and oligonucleic acids with chemically modified ribose sugars on nucleic acid. The column used was Shodex HILICpak VN-50 2D (2.0 mm I.D. column), a Hydrophilic Interaction Liquid Chromatography (HILIC) column which is packed with multi-porous polyvinyl alcohol polymers modified with diol functional groups. This article also includes higher sensitivity analysis using HILICpak VN-50 1D (1.0 mm I.D. column). Oligonucleotide therapeutics, such as antisense nucleic acid drugs, are promising candidates for genetic and metabolic, and cancer treatments. Oligonucleic acids (Oligo-DNAs and Oligo-RNAs) of about 20mer sizes are generally used in approved nucleic acid drugs. Most oligonucleic acids are chemically modified. For example, there are phosphorothioated oligonucleotides modified at its phosphate linkage and oligonucleic acids at both ends of ribose sugars modified with 2'-MOE (2’-Methoxyethyl) or 2’-OMe (2’-O-Methyl). The development and quality control of oligonucleotide therapeutics often require highly selective and sensitive analytical methods. The method utilizing an LC/MS system is one of them. The most often used method for the analysis of oligonucleotides have been reversed phase chromatography with the use of an ion-pair reagent. However, the ion-pair reagents have a tendency to remain on the LC system and lowers the MS sensitivity. The application developed here did not require the use of ion-pair reagents.
20	SEC Multi-Faceted Analysis of Exosome (EV) Combination of UV, Florescence, and Light Scattering Detectors
	This article introduces an example of multi-faceted analysis and monitoring of an EV sample purification process using a SEC column, Shodex OHpak SB-806 HQ, with 3 different detectors. OHpak SB-806 HQ is a SEC column which has sufficient pore size to hold and separate EV-class nanoscale objects of 50 - 200 nm. Exosome, an extracellular vesicle (EV), is responsible for transmitting various information and substances in living organisms. EVs have high expectations used as highly sensitive diagnostic markers and therapeutic applications. Among cell-originated components, the size of EVs are relatively large with diameters around 100 nm. Size exclusion chromatography (SEC) are promising candidate for the separation and analysis of EVs. However, the amount of final EV produced is very small and the majority of its component is lipid membrane. This makes it difficult to be detected by a UV detector. Moreover, the cultured sample contains a large amount of biological impurities, which has high UV absorbance. And thus, this makes the monitoring and identification of EVs difficult. Cultured samples are also known to contain impurities of other nano-scale size components such as dead-cell genome-originated chromatin aggregates. Thus, separation and monitoring using only size exclusion method will not be sufficient in the process development and quality control.
21	Analysis of Indigestible Dextrin
	This article introduces analysis of indigestible dextrin in food following the Japanese Food for Specified Health Uses (FOSHU) standards method. Dietary fiber is an indigestible food component that is difficult to digest by human digestive enzymes. Dietary fiber has preventive effects on dyslipidemia, constipation, obesity, and diabetes, as well as on arteriosclerosis by regulating lipid metabolism. Its many physiological functions have been attracting people’s interests. There are two types of dietary fibers: insoluble and water soluble. Water-soluble dietary fibers are further categorized into two types: high-molecular-weight water-soluble dietary fibers and low-molecular-weight water-soluble dietary fibers. Indigestible dextrin is a low-molecular-weight water-soluble dietary fiber and approved to label as a FOSHU. For nutritional labeling of dietary fiber, the enzyme gravimetric method (Prosky method) has been used. With this method, samples are treated by enzymatic reaction, precipitated using about 80v/v% methanol, and filtered. The residual part contains the dietary fiber, protein, and ash. Prosky method works well for the measurement of high-molecular-weight water-soluble dietary fiber. While it is not suitable for the low-molecular-weight water-soluble dietary fiber measurement as it does not precipitate in about 80 v/v % methanol. An alternative is to use enzyme-HPLC method as developed in this application.
22	Analysis of PFAS Including Ultra Short-Chain PFASNEW
	Per- and polyfluoroalkyl substances, generally known as PFAS are organic compounds that contain fluorine in their structures. Many studies have been conducted on their environmental behavior, toxicity evaluation, and removal, disposal, and analysis methods. Since PFAS are often required to be analyzed at low concentration levels, high-performance mass spectrometers are generally used. Even if the selected eluent achieves good separations of target substances, if it is not suitable for mass spectrometry ionization, the sensitivity will be low. PFAS with carbon number of eight, such as PFOS and PFOA, and PFAS with even longer chains are generally analyzed using reverse-phase columns. However, short-chain PFAS are weakly retained on reverse-phase columns, and thus it is not suitable. In this application, we optimized LC separation conditions to achieve both good sensitivity and separation for short-chain PFAS, PFOS and PFOA, using a Shodex HILICpak VT-50 2D column; which is a polymer-based column modified with a quaternary ammonium functional group.