Mesoporous titania based yolk–shell nanoparticles as multifunctional theranostic platforms for SERS imaging and chemo-photothermal treatment

Wang

et al. 2015

Chemistry A European J

We have rationally designed a new theranostic agent by coating near-infrared (NIR) light-absorbing polypyrrole (PPY) with poly(acrylic acid) (PAA), in which PAA acts as a nanoreactor and template, followed by growing small fluorescent silica nanoparticles (fSiO2 NPs) inside the PAA networks, resulting in the formation of polypyrrole@polyacrylic acid/fluorescent mesoporous silica (PPY@PAA/fmSiO2 ) core-shell NPs. Meanwhile, DOX-loaded PPY@PAA/fmSiO2 NPs as pH and NIR dual-sensitive drug delivery vehicles were employed for fluorescence imaging and chemo-photothermal synergetic therapy in vitro and in vivo. The results demonstrate that the PPY@PAA/fmSiO2 NPs show high in vivo tumor uptake by the enhanced permeability and retention (EPR) effect after intravenous injection as revealed by in vivo fluorescence imaging, which is very helpful for visualizing the location of the tumor. Moreover, the obtained NPs inhibit tumor growth (95.6 % of tumors were eliminated) because of the combination of chemo-photothermal therapy, which offers a synergistically improved therapeutic outcome compared with the use of either therapy alone. Therefore, the present study provides new insights into developing NIR and pH-stimuli responsive PPY-based multifunctional platform for cancer theranostics.

Section: Resultsmentioning

confidence: 88%

Section: Introductionmentioning

confidence: 99%

Near‐Infrared Light and pH‐Responsive Polypyrrole@Polyacrylic acid/Fluorescent Mesoporous Silica Nanoparticles for Imaging and Chemo‐Photothermal Cancer Therapy

Wang

et al. 2015

Chemistry A European J

ACS Appl. Mater. Interfaces

“…To verify the elastic property of the mSiO 2 shell, H 2 O 2 was used for selective dissolution of the Ag coating. Au@ AgNR@mSiO 2 NPs prepared with 150 μL of AgNO 3 were dispersed in 1 mL of water, followed by the addition of different volumes (20,50, and 100 μL) of H 2 O 2 solution (30%, v/v). The reaction was allowed to proceed at room temperature, and the reaction rate was evaluated by monitoring the absorption spectra evolution of the solutions.…”

Section: ■ Experimental Sectionmentioning

confidence: 99%

“Elastic” Property of Mesoporous Silica Shell: For Dynamic Surface Enhanced Raman Scattering Ability Monitoring of Growing Noble Metal Nanostructures via a Simplified Spatially Confined Growth Method

Lin

Wang

Sun

et al. 2015

Self Cite

ABSTRACT:The Raman enhancing ability of noble metal nanoparticles (NPs) is an important factor for surface enhanced Raman scattering (SERS) substrate screening, which is generally evaluated by simply mixing as-prepared NPs with Raman reporters for Raman signal measurements. This method usually leads to incredible results because of the NP surface coverage nonuniformity and reporter-induced NP aggregation. Moreover, it cannot realize in situ, continuous SERS characterization. Herein, we proposed a dynamic SERS monitoring strategy for NPs with precisely tuned structures based on a simplified spatially confined NP growth method. Gold nanorod (AuNR) seed NPs were coated with a mesoporous silica (mSiO 2 ) shell. The permeability of mSiO 2 for both reactive species and Raman reporters rendered the silver overcoating reaction and SERS indication of NP growth. Additionally, the mSiO 2 coating ensured monodisperse NP growth in a Raman reporter-rich reaction system. Moreover, "elastic" features of mSiO 2 were observed for the first time, which is crucial for holding the growing NP without breakage. This feature makes the mSiO 2 coating adhere to metal NPs throughout the growing process, providing a stable Raman reporter distribution microenvironment near the NPs and ensuring that the substrate's SERS ability comparison is accurate. Three types of NPs, i.e., core−shell Au@AgNR@mSiO 2 , Au@AuNR@mSiO 2 , and yolk−shell Au@void@AuNR@mSiO 2 NPs, were synthesized via core−shell overgrowth and galvanic replacement methods, showing the versatility of the approach. The living cell SERS labeling ability of Au@AgNR@mSiO 2 -based tags was also demonstrated. This strategy addresses the problems of multiple batch NP preparation, aggregation, and surface adsorption differentiation, which is a breakthrough for the dynamic comparison of SERS ability of metal NPs with precisely tuned structures and optical properties.

“…The new nano-carriers that have rapidly emerged as drug delivery systems may overcome these limitations. [30][31][32][33][34][35][36][37][38] The drug delivery mechanism of nano-carriers depends on enhanced permeability and retention (EPR) effects. The anticancer drugs are either conjugated to the nano-carriers or packaged as nanocapsules.…”

Section: Jaebum Choomentioning

confidence: 99%

Fluorescent chemical probes for accurate tumor diagnosis and targeting therapy

et al. 2017

Self Cite

Surgical resection of solid tumors is currently the gold standard and preferred therapeutic strategy for cancer. Chemotherapy drugs also make a significant contribution by inhibiting the rapid growth of tumor cells and these two approaches are often combined to enhance treatment efficacy. However, surgery and chemotherapy inevitably lead to severe side effects and high systemic toxicity, which in turn results in poor prognosis. Precision medicine has promoted the development of treatment modalities that are developed to specifically target and kill tumor cells. Advances in in vivo medical imaging for visualizing tumor lesions can aid diagnosis, facilitate surgical resection, investigate therapeutic efficacy, and improve prognosis. In particular, the modality of fluorescence imaging has high specificity and sensitivity and has been utilized for medical imaging. Therefore, there are great opportunities for chemists and physicians to conceive, synthesize, and exploit new chemical probes that can image tumors and release chemotherapy drugs in vivo. This review focuses on small molecular ligand-targeted fluorescent imaging probes and fluorescent theranostics, including their design strategies and applications in clinical tumor treatment. The progress in chemical probes described here suggests that fluorescence imaging is a vital and rapidly developing field for interventional surgical imaging, as well as tumor diagnosis and therapy.