Chitosan gold nanoparticles for detection of amplified nucleic acids isolated from sputum.
A platform for nucleic acid detection employing chitosan and chitosan coated gold nanoparticles (AuNPs) was developed. Mycobacterium tuberculosis (MTB) was used as a model target. MTB DNA was extracted from sputum using simple total nucleic acid extraction. Following amplification of MTB DNA, chitosan and AuNPs were added to samples. Free chitosan conjugated non-target DNA in negative samples, avoiding AuNP-DNA interaction and hence negative samples remained red. In positive samples, amplified DNA was capable of saturating free chitosan leading to AuNP aggregation where positive samples turned blue. Via visual color detection 15/16 MTB positive samples and 3/3 negative samples were correctly identified. This test is a 1-tube, 1-step assay reducing the risk of contamination in molecular laboratories and is a proof of concept on how chitosan; a cheap polymer could increase the sensitivity of AuNPs towards specific detection of nucleic acids without using target specific oligotargeters or expensive extraction kits.
Department of Chemistry, School of Sciences & Engineering, The American University in Cairo, New Cairo, Egypt. Electronic address: Salma.tammam@gmail.com.
Salma N
SN
Tammam
Department of Chemistry, School of Sciences & Engineering, The American University in Cairo, New Cairo, Egypt; Department of Microbiology & Immunology, Faculty of Pharmacy, Misr University for Science and Technology, 6th October City, Egypt. Electronic address: mahmouadfouad@gmail.com.
Mahmoud A F
MA
Khalil
Department of Chemistry, School of Sciences & Engineering, The American University in Cairo, New Cairo, Egypt. Electronic address: eman.bahaaeldin.90@gmail.com.
Eman
E
Abdul Gawad
Health Sciences Department, College of Arts and Sciences, Qatar University, Doha, Qatar. Electronic address: aaja@qu.edu.qa.
Asma
A
Althani
Faculty of Medicine, Mansoura University, Mansoura, Egypt. Electronic address: hosam_z@yahoo.com.
Hosam
H
Zaghloul
Department of Chemistry, School of Sciences & Engineering, The American University in Cairo, New Cairo, Egypt. Electronic address: hazzazy@aucegypt.edu.
Hassan M E
HM
Azzazy
D048271:Chitosan; D004269:DNA, Bacterial / Q000302:isolation & purification*; D006046:Gold; D006801:Humans; D053768:Metal Nanoparticles; D009169:Mycobacterium tuberculosis; D012680:Sensitivity and Specificity; D013183:Sputum / Q000737:chemistry*; D014376:Tuberculosis / Q000175:diagnosis
D004269:DNA, Bacterial; D006046:Gold; D048271:Chitosan
Chitosan; Gold nanoparticles; Mycobacterium tuberculosis; Nucleic acid detection; Sputum samples