A Review on GC-MS Hyphenated Technique

The hyphenated technique is developed from the coupling of a separation technique and an on-line spectroscopic detection technology, GCMS, LC-MS, LC-FTIR, LC-NMR, and CE-MS. Gas chromatography combined with mass spectrometry is an important technique for identification and quantification of analytes in multifactor systems. GC-MS is highly effective and versatile analytical techniques with numerous scientific applications to cater the field of applied Sciences and Technology. This review elaborates the significant uses of this technique. It includes a brief discussion of the instrumental set-up and theory for the comprehensive GC × GC hyphenated with different detection techniques. It is fast and sensitive, provides a high peak capacity, and allows determination of thermally stable and volatile compounds.

A Universal Positioning System for Coupling Characterization of SEM and AFM

Hyphenated techniques, providing comprehensive information in various aspects such as constituent, structure, functional group, and morphology, play an important role in scientific research. Nowadays, coupling characterization of the same position in microscale is in great need in the field of nanomaterial research and exploration. In this article, a new hyphenated technique was developed to facilitate the coupling characterization of atomic force microscope (AFM) and scanning electron microscope (SEM) by designing a universal positioning system. The system consisted of a specimen holder with coordinate grids and a software for converting the coordinate values of the same point to fit SEM, specimen holder, and AFM system. In working condition, the coordinates of the labeled points and target position were firstly extracted from the SEM operation software, then converted into the numerical values adapted to the specimen holder itself, and finally transformed into the coordinates matching the AFM system. The experimental result showed that a retrieving rate of 96% was achieved for a spherical target with a diameter of 1 μm in a 30 μ m × 30 μ m square. The hyphenated technique is a universal, accurate, efficient, and financially feasible method in microanalysis field and has great application potential.

A Tapered Capillary-Based Contactless Atmospheric Pressure Ionization Mass Spectrometry for On-Line Preconcentration and Separation of Small Organics

Capillary electrophoresis (CE) is an effective technique for the separation of different analytes. Moreover, online preconcentration of trace analytes in the capillary for CE analysis has been demonstrated. CE and capillary electrochromatography (CEC) are suitable for the separation of analytes with similar polarities. Given that CE and CEC are only used to separate small-volume samples, sensitive mass spectrometry (MS) is a suitable detection tool for CE and CEC. Contactless atmospheric pressure ionization (C-API) is a continuous flow ion source that only uses a short capillary as the ionization emitter operated at atmospheric pressure for MS analysis. In this study, we demonstrated the feasibility of hyphenating CE/CEC with C-API-MS by using a short and tapered capillary as the interface. The short capillary (a few centimeters) can function as the separation/preconcentration tube and the ionization emitter. This hyphenated technique can be used to analyze small organics within a few minutes. The suitability of using the hyphenated technique for online preconcentration, separation, and quantitative analysis for small organics is demonstrated in this study.

Qualitative Analysis of Post-blast Residue using the Double Hyphenated UHPLC-(HESI)-MS/MS Technique

The thriving terror activity is a menace to our society. To mitigate this, there is a dire need of upgraded and innovative analytical techniques for forensic analysis of explosives. The complexity in the matrix, restrictions in the sample quantity and ambiguity in the data interpretation are the different challenges that a forensic scientist face. The solution to these problems lies in upgradation of extraction technique, screening technique & confirmatory techniques. In this paper, the identification and forensic analysis of post blast residues recovered from controlled blast site has been presented. The targeted sample was extracted from soil by using Accelerated Solvent Extraction technique. The target compound was primarily identified to be PETN (PentaErythritol TetraNitrate) by color test and TLC (Thin Layer Chromatography). The confirmatory test for the target analyte was done by using a hyphenated technique LC-MS/MS (Liquid Chromatography Mass Spectrometer with tandem Mass). This manuscript demonstrates the viability of LC-MS/MS in Forensic Science for a fast, accurate and quality-assured analysis of post-blast residue.

A Review on Analytical Methods for estimation of Apremelast in Bulk, Pharmaceutical Formulation and in Biological Samples

Apremilast is approved by USFDA in 2014. It is used in treatment of psoriatic arthritis and other conditions like atopic dermatitis and plaque psoriasis. It is act as an anti-inflammatory agent. It is phthalimide derivative and belongs to class 4 category of BCS system. It is a phosphodiesterase-4 (PDE-4) inhibitor. Analytical methods plays an important role to describe physico-chemical properties of drug. Due to low solubility and low permeability analytical method development and formulation becomes challenging. Till date, there are no standard test methods available to analyze Apremilast. So, a review of the analytical methods for apremilast is carried out. Here we discussed latest analytical methods for estimation of apremilast in bulk, Pharmaceuticals dosage form and in biological samples. In that we study methods like HPLC, UV-Visible spectroscopy, HPTLC, UPLC and mostly used hyphenated technique LC-MS. This review will be helpful for the researcher who is working on apremilast.

Development of bimetal-organic frameworks-polypyrrole composite as a novel fiber coating for direct immersion solid phase microextraction in-situ supercritical fluid extraction coupled to gas chromatography for simultaneous determination of furfurals in dates

A new, simple, hyphenated technique couples supercritical fluid extraction and direct immersion SPME to GC-FID (SFE–DI-SPME–GC–FID) for the determination of 2-furaldehyde (2-F) and 5-hydroxymethylfurfural (5-HMF) in solid foods. A bimetal-organic...

Corncob Waste Based Adsorbent for Solid Phase Extraction of Tartrazine in Carbonated Drinks and Analytical Method using Ultra Performance Liquid Chromatography-Mass Spectrometry

Background : A new method has been developed for the determination of food dye tartrazine in soft drinks. Tartrazine is determined by hyphenated technique Ultra Performance Liquid Chromatography coupled with Mass spectrometry. The solid-phase extraction was used for the extraction of tartrazine. Methods: For the LC-MS analysis of tartrazine acetonitrile, water (80:20) was used as a mobile phase whereas, the C-18 column was selected as the stationary phase. The chromatographic run was allowed for 1 min. The adsorbent of the solid-phase extraction was synthesized from the waste corn cob. Results: Method found to be linear in the range of 0.1 mg L-1 - 10 mg L-1, limits of detection and quantitation were found to be 0.0165 mgL-1 and 0.055 mgL-1, respectively. Tartrazine, in the real sample, was found to be 20.39 mgL-1 and 83.26 mgL-1. Conclusion: The developed UPLC-MS method is rapid, simple, precise and can be used for the quantitative analysis of tartrazine. The solid-phase extraction also involves a cost-effective procedure for extraction as it does not involve the commercial cartridge.

IMPURITY PROFILING IMPURITY PROFILING OF THIAMINE HYDROCHLORIDE INJECTION BY RP-HPLC AND CHARACTERIZATION OF DEGRADATION PRODUCT BY LC-MS/MS/QTOF

Objective: To propose a comprehensive, simple, and affordable RP-HPLC method for impurity profiling and characterization of unknown degradation products of thiamine hydrochloride injectable formulation. Methods: The chromatographic separation employs gradient mode using the octadecyl silane column using a mobile phase consisting of phosphate buffer with ion pair reagent, acetonitrile, and methanol delivered flow rate at 1.2 ml/min. The detection was carried out at 248 nm using empower software. LC-MS/MS/QTOF hyphenated technique was used for isolation and characterization of unknown degradation impurity. The performance of the method was systematically validated as per ICH Q2 (R1) guidelines. Results: Degradation product observed in accelerated stability was characterized by LC-MS/MS/QTOF hyphenated technique and found m/z value 351.1604 and postulated as an oxidative degradation product of thiamine due to excipient interaction. The validated method was sensitive, selective, and specific data proves the method is precise and accurate from LOQ to 150% level and results are within 95-108% and less than 4.5% RSD. The developed method is linear from 0.03-58.83 µg/ml with a correlation coefficient of more than 0.990 and LOD and LOQ value ranged from 0.03 to1.51 μg/ml. Conclusion: An efficient RP-HPLC method for impurity profiling of thiamine injectable formulation was successfully developed and unknown degradation product observed instability condition samples characterized by LC-MS/MS/QTOF technique. The validated method can be successfully employed for the impurity profiling of thiamine injectable in the quality control department.

TLC Bioautography on Screening of Bioactive Natural Products: An Update Review

Background: TLC bioautography is a hyphenated technique combining planar chromatographic separation and in situ biological activity detection. This coupled method has been receiving much attention in screening bio-active natural products because of its properties of being simple, rapid, inexpensive, and effective. Methods: The recent progress in the development of method of TLC bioautography for detecting antimicrobial and enzyme inhibitory activities dating between 2012 and early 2018 has been reviewed. The applications of this method in biological screening of natural products were also presented. Results: Some anaerobic and microaerophilic bacteria and a causative bacterium of tuberculosis have been adopted to TLC direct bioautography. Seven types of enzymes including acetylcholinesterase, glucosidase, lipase, xanthine oxidase, tyrosinase, monoamine oxidase, and dipeptidyl peptidase IV have so far been adopted on TLC bioautography. Its new application in screening antiurolithiatic agents was included. Conclusion: The standard experimental procedures are required for TLC antioxidant and antimicrobial assays. Some new enzymes should be attempted and adopted on TLC bioautography. The existing TLC methods for enzyme inhibition need more application studies to assess their screening capacity in the discovery of active compounds. The GC-MS or LC-MS approaches have gradually been coupled to TLC bioautography for fast structural characterization of active compounds.