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Start Over Topic beta lactam antibiotics Publication Year Range Last 10 years
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1. Phenotypically distinguishing ESBL-producing pathogens using paper-based surface enhanced Raman sensors.

Author

Hilton, Shannon H., Hall, Connor, Nguyen, Hieu T., Everitt, Micaela L., DeShong, Philip, and White, Ian M.

Subjects
*SERS spectroscopy, *LACTAMS, *BETA lactam antibiotics, *MEDICAL microbiology, *MULTIDRUG resistance, *DETECTORS, *CHEMICAL synthesis
Abstract

Antimicrobial stewardship practices are critical in preventing the further erosion of treatment options for bacterial infections. Yet, at the same time, determination of an infection's antimicrobial susceptibility requires multiple rounds of culture and expensive lab automation systems. In this work, we report the use of paper-based surface enhanced Raman spectroscopy (SERS) sensors and portable instrumentation to phenotypically discriminate multi-drug resistance with fewer culture steps than conventional clinical microbiology. Specifically, we demonstrate the identification of resistance to varying generations of β -lactam antibiotics by detecting the activity of particular β -lactamase enzymes in a multiplexed assay. The method utilizes molecular reporters that consist of β -lactams with SERS barcodes. Hydrolysis of the β -lactam by β -lactamase enzymes in the sample expels the barcode; the released sulfur-containing barcode is then detected via SERS. Using this approach, we demonstrate the differentiation of E. coli strains with (1) extended spectrum β -lactamase (ESBL), (2) narrow-spectrum β -lactamase, and (3) no resistance, using only a single measurement on a single sample. In addition, we experimentally validate an approach to expand the library of reporters through the simple chemical synthesis of new barcoded β -lactams. Importantly, the reported method determines the susceptibility based on phenotypic β -lactamase activity, which is aligned with current microbiology lab standards. This new method will enable the precise selection of effective β -lactam antibiotics (as opposed to defaulting to drugs of last resort) faster than current methods while using simple steps and low-cost portable instrumentation. Image 1 • We demonstrate phenotypic detection of β-lactamase activity using paper SERS sensors and portable instrumentation. • We show discrimination of β -lactamases with different degrees of resistance in a single sample on a single sensor. • We demonstrate a simple synthesis method to expand the library of SERS-based β -lactamase reporters. • We accomplish β-lactamase discrimination in significantly less time than conventional microbiology. [ABSTRACT FROM AUTHOR]

Published
2020
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2. Paper-Based Enzyme Competition Assay for Detecting Falsified β-Lactam Antibiotics

Author

Joseph Caraway, Cody S. Carrell, Katherine E. Boehle, and Charles S. Henry

Subjects
Paper, medicine.drug_class, Antibiotics, Bioengineering, beta-Lactams, 01 natural sciences, beta-Lactamases, Antibiotic resistance, medicine, Nitrocefin, Instrumentation, Enzyme Assays, Fluid Flow and Transfer Processes, Active ingredient, chemistry.chemical_classification, 010405 organic chemistry, Chromogenic, Process Chemistry and Technology, 010401 analytical chemistry, Paper based, Equipment Design, Microfluidic Analytical Techniques, 0104 chemical sciences, Anti-Bacterial Agents, Cephalosporins, Enzyme, Biochemistry, chemistry, Counterfeit Drugs, Business, Beta lactam antibiotics, Tablets
Abstract

Falsified and substandard antibiotics are a growing worldwide problem that leads to increased patient mortality and decreased trust in healthcare, and contributes to antimicrobial resistance. Monitoring falsified antibiotics is difficult because most falsified pharmaceuticals are most commonly found in developing countries, where detecting the active ingredient is difficult due to lack of access to complex instrumentation. Herein, we describe the development and optimization of a microfluidic paper-based analytical device (μPAD) to detect the active ingredient in the most falsified class of antibiotics, β-lactams. The assay is based on enzyme competition, making it the first demonstrated competitive enzyme assay reported in paper-based devices. The assay uses nitrocefin, a chromogenic substrate, to compete with β-lactam antibiotics in a reaction with β-lactamase. A yellow color indicates legitimate drugs, while a color change from yellow to red indicates falsified drugs. In addition to testing for the active ingredient, another section of the device was added to test the sample pH to further verify results and identify common falsified ingredients like aspirin or baking soda. Calibration curves for four different antibiotics, including cefazolin, have been generated making it the first paper-based device capable of detecting both cephalosporin and penicillin antibiotics. The μPAD has also been tested with common falsified ingredients and four antibiotics in tablet or injectable form, demonstrating its potential for in-field falsified antibiotic testing.

Published
2018