Highly specific plasmonic biosensors for ultrasensitive microRNA detection in plasma from pancreatic cancer patients.
MicroRNAs (miRs) are small noncoding RNAs that regulate mRNA stability and/or translation. Because of their release into the circulation and their remarkable stability, miR levels in plasma and other biological fluids can serve as diagnostic and prognostic disease biomarkers. However, quantifying miRs in the circulation is challenging due to issues with sensitivity and specificity. This Letter describes for the first time the design and characterization of a regenerative, solid-state localized surface plasmon resonance (LSPR) sensor based on highly sensitive nanostructures (gold nanoprisms) that obviates the need for labels or amplification of the miRs. Our direct hybridization approach has enabled the detection of subfemtomolar concentration of miR-X (X = 21 and 10b) in human plasma in pancreatic cancer patients. Our LSPR-based measurements showed that the miR levels measured directly in patient plasma were at least 2-fold higher than following RNA extraction and quantification by reverse transcriptase-polymerase chain reaction. Through LSPR-based measurements we have shown nearly 4-fold higher concentrations of miR-10b than miR-21 in plasma of pancreatic cancer patients. We propose that our highly sensitive and selective detection approach for assaying miRs in plasma can be applied to many cancer types and disease states and should allow a rational approach for testing the utility of miRs as markers for early disease diagnosis and prognosis, which could allow for the design of effective individualized therapeutic approaches.
Department of Chemistry and Chemical Biology, Indiana University-Purdue University Indianapolis , 402 N. Blackford Street, LD 326, Indianapolis, Indiana 46202, United States.
Gayatri K
GK
Joshi
Samantha
S
Deitz-McElyea
Merrell
M
Johnson
Sonali
S
Mali
Murray
M
Korc
Rajesh
R
Sardar
D014408:Biomarkers, Tumor / Q000097:blood*; D015374:Biosensing Techniques / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006046:Gold / Q000737:chemistry; D006801:Humans; D053768:Metal Nanoparticles / Q000737:chemistry / Q000648:ultrastructure; D035683:MicroRNAs / Q000097:blood*; D008832:Microchemistry / Q000295:instrumentation; D010190:Pancreatic Neoplasms / Q000097:blood* / Q000235:genetics / Q000378:metabolism*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D020349:Surface Plasmon Resonance / Q000295:instrumentation*
D014408:Biomarkers, Tumor; D035683:MicroRNAs; D006046:Gold
Nanoprisms; label-free detection; localized surface plasmon resonance; microRNAs; pancreatic cancer; patient plasma