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Rapid Detection of Carbapenemase-Producing Enterobacteriacae Based on Surface-Enhanced Raman Spectroscopy with Gold Nanostars
journal contribution
posted on 2020-03-26, 19:36 authored by Yen Lynn Wong, Wei Cherng Malvin Kang, Miguel Reyes, Jeanette Woon Pei Teo, James Chen Yong KahThe
emergence and rapid spread of antibiotic resistance poses a serious
threat to healthcare systems across the globe. The existence of carbapenemase-producing
Enterobacteriaceae (CPE) such as Klebsiella pneumoniae renders the use of carbapenems, the last-resort class of β-lactam
antibiotics, ineffective against bacterial infections, often leading
to CPE-associated mortalities. Current methods of detection such as
the Carba NP test and modified Hodge’s test require hours to
days to detect, which delays the response to isolate patients for
rapid intervention. Here, we developed a surface-enhanced Raman scattering
(SERS)-based detection scheme which utilizes gold nanostars conjugated
to a β-lactam antibiotic ceftriaxone (CRO) as a beacon for rapid
detection of bacterial β-lactamase secreted by Delhi metalloproteinase
(NDM)-producing Escherichia coli as our CPE model
with carbapenemase activity. The cleavage of β-lactam ring in
CRO by NDM (Class B β-lactamase) caused a detectable reduction
in SERS intensities at 722, 1358, and 1495 cm–1 within
25 min. Ratiometric analysis of the SERS peaks at 722, 1358, and 1495
cm–1 normalized against the Raman peak of polystyrene
cuvette at 620 cm–1 showed the peak at 1358 cm–1 having the most significant change in intensity upon
CPE detection. This reduced detection time has not been reported to
date for CPE detection, and our novel approach using SERS could be
extended to detect the activity of other classes of β-lactamases
to broaden its clinical utility.