A screening and confirmation method for veterinary drugs and additives in animal-derived food, including: preparation of standard working solution, pretreatment of samples to be tested, establishment of database, sample detection, compound screening and compound confirmation. The disclosure employs ultra high performance liquid chromatography-quadrupole/electrostatic field orbitrap high resolution mass spectrometry, and enables the simultaneous detection of 207 veterinary drugs and additives in animal-derived food within 22 min.

Disclosed are a size exclusion chromatography-combined nitrogen detector and an application method thereof, which belong to the field of detection and analysis of water quality. The detector comprises an oxidation system (1), a nitrate detection system (2), a power supply system (3), and a signal processing and control system (4), wherein after being separated by size exclusion chromatography, a sample to be detected enters into the oxidation system (1) to undergo oxidation treatment, and after nitrogenous compound in the sample is converted into nitrate, the sample is detected in the nitrate detection system (2) by ultraviolet (UV) absorbance method. The power supply system (3) supplies power to the detector, and the signal processing and control system (4) is responsible for processing and controlling signals of the oxidation system (1) and the nitrate detection system (2). The detector can achieve quantitative analyses of total nitrogen, organic nitrogen, nitrate nitrogen, and ammonia nitrogen, has the advantages of easiness in operation, being rich in information, etc. and thereby effectively prevents the problems of relatively large error and negative value resulting from the subtraction calculation in conventional organic nitrogen analysis methods.

An odor analysis system is provided to analyze odors present at a particular location and perform a preliminary identification of the odors while still at the location. The odor analysis system can have an odor processing device that collects samples of the odors and provides a series of odor notes to a user. The odor notes can be based on the separated and concentrated molecules in the collected sample. The odor analysis system can also include a hand-held computing device with a user interface that permits the user to enter information, both verbally and through touch input, about the series of odor notes provided by the odor processing device. The information entered by the user about the series of odor notes along with retention index information about the series of odor notes can be to perform a preliminarily identification of the molecules associated with the odors present at the location.

A method for reducing the variability, as measured by relative standard deviation (RSD), of an analytical testing technique is provided. This improvement in RSD improves the confidence in the values obtained during field testing. The method includes incorporating a focusing agent into the sampling media, which permits providing sampling media such as thermal desorption tubes preloaded with the focusing agent.

To enable appropriate analysis to easily be performed in accordance with an object to be analyzed, provided is an apparatus for determining a chromatograph analysis method includes: an input portion (220) configured to receive input of a sample name of a sample to be analyzed and a component name; a storage (230) configured to store an analysis method for a component corresponding to the component name in the sample corresponding to the sample name so that the analysis method is associated with the sample name and the component name; and a controller (210) configured to search the storage for the analysis method, which corresponds to the sample name and the component name input to the input portion, to read the analysis method from the storage, and present the analysis method to a user.

An alternating flow column chromatography apparatus comprising a U shaped or T shaped separation column including at least one loading port for loading of components for separation, a first purification column in fluid communication with one end of the separation column and a second purification column in fluid communication with another end of the separation column, at least one eluent input port, an eluate output port and an alternating flow valve in fluid communication with the primary eluent input port, the eluate output port, the first purification column and the second purification column wherein, when operated, the alternating flow valve reverses the flow of eluent through the purification columns and the separation column. Also a method of using the apparatus. A benefit of the apparatus and method is more efficient operation compared to existing direct flow column chromatography apparatuses.

A high performance liquid chromatography method used for dexrazoxane-related substances is provided, and in the method, a low-density bonding reversed-phase C18 chromatographic column resistant to pure water is employed; a gradient elution is carried out with mobile phase A and mobile phase B as eluents, the mobile phase A being a buffer, and the mobile phase B being an organic solvent; the volume percent of mobile phase A in eluents in a first stage of the gradient elution is not lower than 90%, and the duration of the first stage of the gradient elution ranges from 1530 minutes. By means of the analytical method, dexrazoxane is effectively separated from main impurities, and the qualities of the active pharmaceutical ingredients of dexrazoxane and the preparations thereof could be better controlled.

In one aspect, a method for detecting the labelling state of unknown species of molecules M contained in a sample exposed to a non-changing isotope labelling process using mass spectrometry is described.

A method of ionizing a sample is disclosed comprising performing an initial experiment comprising: (i) adding one or more reagents to an analyte sample; (ii) varying the composition and/or concentration of the one or more reagents; (iii) ionizing the analyte sample including the one or more reagents; (iv) determining the composition and/or concentration of the one or more reagents which results in a desired, improved or optimized ionization or other condition or parameter for one or more analytes of interest; and (v) determining one or more first retention times or one or more first retention time windows for the one or more analytes of interest. The method then further comprises separating an analyte sample using a first separation device and during the course of a single experimental run or acquisition varying the composition and/or concentration of one or more reagents which are added to an eluent which emerges from the first separation device. The composition and/or concentration of the one or more reagents which are added to the eluent is varied at the one or more the first retention times or during the one or more the first retention time windows so that an ionization or other condition or parameter for the one or more analytes of interest is as desired or is improved or optimized.

A distributable sampling and sensing instrument for chemical analysis of consumable foods and other agricultural products. The distributable sampling system is used to separate and concentrate the chemicals of interest obtained from samples at remote locations via thermal desorption onto a detachable target substrate that can be analyzed on-site or off-site. The volatile components adsorbed onto the target substrate can be analyzed with specific sensors (e.g., electrochemical sensors) or the assembly can be sent to a central lab and analyzed with conventional chemical instrumentation (e.g., GC-MS). This instrument provides the capability to enable chemical analysis of a wide range of chemical species of interest in a wide range of environments and conditions.