These theranostic techniques rely on the successful delivery and detection of nanoparticles at the diseased sites. In particular, nanotechnology can be used to tailor treatment to individual patients by integrating diagnostic and therapeutic capabilities into a single entity. One advantage of nanoparticles over small molecular compounds is their ability to perform multiple functions simultaneously.

Aptamer is a promising ligand for image-guided delivery of nanoparticles for treatment of tumor cells overexpressing EGFR.

μSPECT/CT imaging confirmed that there was more tumor uptake of apt-HAuNS than C225-HAuNS. In vitro cell binding and in vivo biodistribution showed selective binding of the apt-HAuNS to EGFR. The number of aptamers/particle was ∼250. The surface charge became more negative upon conjugation of the aptamer (−51.4 vs −19.0 for PEG-HAuNS and −25.0 for C225-HAuNS). Apt-HAuNS did not have an altered absorbance profile or size (λ max = 800 nm diameter = 55 nm) compared to C225-HAuNS or PEG-HAuNS. 111In-labeled PEG-HAuNS was used as a control ( n = 5/group). The in vivo pharmacokinetics, in vivo biodistribution, and micro-SPECT/CT imaging of 111In-labeled apt-HAuNS and anti-EGFR antibody (C225)-conjugated HAuNS were evaluated in nude mice bearing highly malignant human OSC-19 oral tumors. Apt-HAuNS was characterized in terms of size, surface charge, absorption, and number of aptamers per particle. EGFR-targeting aptamers were conjugated to HAuNS (apt-HAuNS) by attaching a thiol-terminated single-stranded DNA to the HAuNS and then adding the complementary RNA targeted to EGFR. The purpose of this study was to compare the binding affinity and selective targeting of aptamer- and antibody-coated hollow gold nanospheres (HAuNS) targeted to epidermal growth factor receptors (EGFR).

Dark injection mod spore