Multi-Omics for biomedical applications.
J. Appl. Bioanal. 22 April 2020. Sharif Khan M and Azmir Jannatul. JAB-2020-2-3/R1 |Download PDF | Special Issue “Omics and Multi-Omics for biomedical applications“.
Multi-omics is a rising filed in –omics science. Despite progress in the multiple single –omics platform, the holistic look at the complex nature of the human cell, disease, and other biochemical pathways remain undiscovered. The multi-omics is considered the most integrated system currently available to obtain and measure the biochemical data-driven information for biomedical problems. The current review will look at the factors that play important roles in the rise of the multi-omics field and its application in biomedical studies.
An LC-MS/MS assay for the simultaneous quantitation of thromboxane B2 and prostaglandin E2 to evaluate cyclooxygenase inhibition in human whole blood
J. Appl. Bioanal. 16 June 2020. Shi Y, Murrey HE, Ahn K, Weng N, Patel S. JAB-2020-5-1/R1 |Download PDF | Regular Article
Objectives: A high-throughput LC-MS method for TXB2 and PGE2 was developed for human whole blood assay for COX inhibition. Methods: A surrogate analyte approach was used for the quantitation of TXB2 and PGE2 by LC-MS. Fifty microliters plasma was processed using solid-phase extraction. TXB2-d4 and PGE2-d4 were used as surrogate analytes. The calibration curves were established for TXB2 from 0.1 to 500 ng/mL and for PGE2 from 0.05 to 500 ng/mL. TXB1 was used as internal standard. Results: The response factor and parallelism between surrogate and authentic analyte were verified. Heparinized whole blood assay for COX inhibition was optimized for sample pretreatment, stimulant concentration and incubation time. Conclusion: The LC-MS assay was successfully used to analyze inhibitory activity of four commercially available COX inhibitors. The presented method offers a sensitive, high throughput and low-cost alternative to ELISA for human whole blood assay for COX inhibition.
Clinical Applications of Circulating Tumor DNA, Circulating Tumor Cells, and Exosomes as Liquid Biopsy-Based Tumor Biomarkers
J. Appl. Bioanal. 27 June 2020. Yan A, Yeh C, Zou L. JAB-2020-4-1/R1
Download PDF | Review
Along with improved knowledge of cancer biology and biotechnical progress, the diagnostic approaches have evolved from tissue biopsies to liquid biopsies. As they provide a minimally invasive tumor detection, liquid biopsies allow early diagnosis and serial assessments of tumor progression. Discovery and use of circulating tumor markers circulating tumor DNA (ctDNA), circulating tumor cells (CTC), and exosomes have largely expanded the possibility of early diagnosis of cancer, patient stratification, as well as developing a personalized treatment. Based on these circulomes, liquid biopsies can be developed, but each type of liquid biopsies has its own merits and limitations. While ctDNA-based methods represent the most advanced techniques, sensitivity improvement is expected given the rarity of ctDNA in circulation. As intact cancer cells, CTC provide information on cancer cells. However, current CTC capturing procedures are still lack of efficiency. Exosomes are abundant, but they are highly heterogeneous and there is a lack of specific markers for identification. Future efforts are needed to improve operational parameters and clinical performance of each method. Prior to a broad use in clinical settings, it is crucial to standardize the procedure for the specific liquid biopsy method and validate the test with adequate specificity and sensitivity for clinical applications
Liquid Chromatography and Tandem Mass Spectrometry Method for the Quantitative Determination of Tanespimycin and its Active Metabolite in Human Plasma: Method Validation and Overcoming an Insidious APCI Source Phenomenon
J. Appl. Bioanal. 31 July 2020. Faria M et al. JAB-2020-2-1/R2
Download PDF | Original Research
A sensitive method was developed and validated for the measurement of tanespimycin (17-(allylamino)-17-demethoxygeldanamycin, BMS-722782, 17-AAG) and its active metabolite 17-(amino)-17-demethoxygeldanamycin (17-AG) in human plasmausing tanespimycin –13C3,15N as an internal standard. The assay was validated over the concentration range of 10.0 to 2500 ng/mL for tanespimycin and 5.00 to 1250 ng/mL for 17-AG. The samples were extracted by protein precipitation and analyzed on an LC-MS/MS system using reversed phase chromatography. Ionization was carried out using an APCI source. During method development, an internal standard variability due to an in-source reduction of the quinone moiety during ionization was observed. This paper describes various approaches to mitigate the impact of in-source reduction: selection of appropriate mobile phases, internal standard concentration, injection volume, source temperature, and continuous maintenance of the source between runs.
A simplified interface for handling microtitre plate assays with the Hamilton Microlab STAR
J. Appl. Bioanal. 02 August 2020. Ng N et al. JAB-2020-6-2/R1
Download PDF | Application Note
Automated liquid handling stations such as the Hamilton Microlab range can be implemented to greatly enhance throughput of cell-based and cell-free assays. To facilitate utilisation past the comprehensive programming interface of the Hamilton Method Editor this paper presents a user interface (UI) that runs within Hamilton Venus and allows for a user to control and store programs for plate-to-plate transfers and serial dilutions in 96 well plate format. The interface allows rapid control of aspiration and dispensing height, trituration, control of tip rack selection, and includes a tip washing program that can reduce the number of disposable tips utilised. The simple program interface allows the Hamilton Microlab to be used as a readily deployable microtitre plate handler, particularly for applications such as aliquoting cells for seeding, diluting a number of plates in medium, or transferring drug dilution arrays to multiple plates. This paper also discusses various optimisations to increase accuracy and rate of low volume liquid transfer. While complex liquid handling tasks such as high-throughput drug screening requires established core facilities, standalone liquid handlers with simplified interfaces can be utilised for smaller-scale research applications and educational purposes.