Rolling circle amplification-Induced Self-Assembly of gold nanorods to form One-Dimensional arrays Equipped ‘Multi-Locator’ for fluorescence imaging and enhancement photothermal tumor therapy

Abstract

An imperative issue for achieving good photothermal therapy is to strengthen the photothermal effect of the photosensitizer. Therefore, the rolling circle amplification (RCA) chain generated by the rolling circle amplification reaction was used to induce the self-assembly of gold nanorods (AuNRs) after attaching multiple AS1411 aptamers to form one-dimensional arrays of AuNRs. Due to the presence of multivalent aptamers and AuNRs, RCsL₁Au can be utilized for fluorescent imaging and photothermal therapy specifically targeting cancer cells. Due to plasma-plasma interactions between AuNRs, the absorption peak of one-dimensional (1D) self-assembled RCsL₁Au at a wavelength of 808 nm is increased compared to AuNRs and L₁-AuNRs, and the temperature is nearly 10℃ higher. The maximum temperature increase in the RCsL₁Au system corresponded to the highest yield achieved at this specific ratio (1:10). Compared to monovalent aptamers, RCsL₁Au with multivalent aptamers exhibits an approximately 57-fold enhancement in its cancer cell targeting efficacy. Additionally, the study demonstrated that incorporating doxorubicin (DOX) into RCsL₁Au to create RCsL₁Au@DOX has a more pronounced impact on synergistic therapy, resulting in a cancer cell killing rate of up to 70 %. This combined therapeutic platform of enhanced photothermal therapy with precise targeting provides new ideas for cancer detection and photothermal therapy.

Novelty Statement

In this study, we designed a multivalent spatially activatable nanoplatform (MA-NV@DOX-Cas13a) based on rolling circle reactions (RCA) for and imaging and treatment of melanoma cells. The nanoplatform not only has good specificity and sensitivity in recognizing target cells but also can inhibit and kill target cancer cells. It has application value in cancer cell detection and treatment.