Evaluation of fluorochromes for flow cytometric detection of Cryptosporidium parvum oocysts labelled by fluorescent in situ hybridization.
Oligonucleotide probes specific to Cryptosporidium parvum (CRY1) were conjugated with a range of fluorochromes. The fluorescence after in situ hybridization (FISH) labelling of oocysts and controls was assessed. The objective was to determine the most suitable conjugate for FISH labelling, followed by analysis with a 488 nm laser flow cytometer. The most promising candidate was fluorescein isothiocyanate but only when linked to the CRY1 probe via an 18-carbon spacer arm consisting of six ethylene glycol moieties. The use of the spacer increased fluorescent signals fivefold compared with an equivalent probe in which the FITC was linked directly to the 5'-amino group of the DNA.
Deere
D
D
Macquarie University Centre for Analytical Biotechnology, School of Biological Sciences, Macquarie University, Sydney, Australia.
Vesey
G
G
Ashbolt
N
N
Davies
K A
KA
Williams
K L
KL
Veal
D
D
D000818:Animals; D016785:Cryptosporidium parvum / Q000302:isolation & purification*; D005434:Flow Cytometry; D005456:Fluorescent Dyes; D017404:In Situ Hybridization, Fluorescence
D005456:Fluorescent Dyes