title: Detection of unamplified HCV RNA in serum using a novel two metallic nanoparticle platform.
abstract: BACKGROUND
  The unique properties of metallic nanoparticles have enabled their utilization in biosensing applications. A novel assay for the detection of hepatitis C virus (HCV) RNA in serum specimens has been developed using magnetic nanoparticles and unmodified cationic gold nanoparticles (AuNPs).
  
  
  METHODS
  HCV RNA was extracted using magnetic nanoparticles functionalized with an oligonucleotide specific to HCV RNA. Extracted RNA is reacted with oligonucleotide sequence specific for HCV RNA in presence of unmodified cationic AuNPs. In positive samples, AuNPs are aligned onto the phosphate backbone of the RNA and their aggregation changes the solution color from red to blue. In the absence of target, solution color remains red. The assay has been tested on 50 serum clinical samples (25 HCV positive and 25 controls).
  
  
  RESULTS
  The dual nanoparticles assay detected HCV RNA in serum and generated comparable results to real-time PCR. The assay had specificity and a sensitivity of 96% and 96.5%, respectively, and a detection limit of 15 IU/mL.
  
  
  CONCLUSIONS
  The developed colorimetric dual nanoparticles HCV RNA assay is simple and inexpensive and can be used for rapid detection of unamplified HCV RNA in serum. Similar sensing platforms can be developed to detect other nucleic acid targets.
authors.forename: Sherif M
authors.initials: SM
authors.lastname: Shawky
authors.forename: Bassem S
authors.initials: BS
authors.lastname: Guirgis
authors.forename: Hassan M E
authors.initials: HM
authors.lastname: Azzazy
mesh_terms: D003124:Colorimetry; D006526:Hepatitis C / Q000097:blood* / Q000821:virology*; D006801:Humans; D053768:Metal Nanoparticles / Q000737:chemistry*; D012367:RNA, Viral / Q000097:blood* / Q000302:isolation & purification; D060888:Real-Time Polymerase Chain Reaction; D012680:Sensitivity and Specificity
chemical_list: D012367:RNA, Viral