Maltotriose-based probes for fluorescence and photoacoustic imaging of bacterial infections
Aimen Zlitni, Gayatri Gowrishankar, Idan Steinberg, Tom Haywood, Sanjiv Sam GambhirNature Communications2020
Currently, there are no non-invasive tools to accurately diagnose wound and surgical site infections before they become systemic or cause signiﬁcant anatomical damage. Fluorescence and photoacoustic imaging are cost-effective imaging modalities that can be used to noninvasively diagnose bacterial infections when paired with a molecularly targeted infection imaging agent. Here, we develop a ﬂuorescent derivative of maltotriose (Cy7-1-maltotriose), which is shown to be taken up in a variety of gram-positive and gram-negative bacterial strains in vitro. In vivo ﬂuorescence and photoacoustic imaging studies highlight the ability of this probe to detect infection, assess infection burden, and visualize the effectiveness of antibiotic treatment in E. coli-induced myositis and a clinically relevant S. aureus wound infection murine model. In addition, we show that maltotriose is an ideal scaffold for infection imaging agents encompassing better pharmacokinetic properties and in vivo stability than other maltodextrins (e.g. maltohexose).