Aptamer-conjugated gold nanorods (AuNRs) are excellent candidates for targeted hyperthermia therapy of cancer cells. However, in high concentrations of AuNRs, aptamer conjugation alone fails to ...result in highly cell-specific AuNRs due to the presence of positively charged cetyltrimethylammonium bromide (CTAB) as a templating surfactant. Besides causing nonspecific electrostatic interactions with the cell surfaces, CTAB can also be cytotoxic, leading to uncontrolled cell death. To avoid the nonspecific interactions and cytotoxicity triggered by CTAB, we report the further biologically inspired modification of aptamer-conjugated AuNRs with bovine serum albumin (BSA) protein. Following this modification, interaction between CTAB and the cell surface was efficiently blocked, thereby dramatically reducing the side effects of CTAB. This approach may provide a general and simple method to avoid one of the most serious issues in biomedical applications of nanomaterials: nonspecific binding of the nanomaterials with biological cells.
In this aritcle, we have developed an interesting imaging method for intracellular ATP molecules with semiquantitation. While there has been a lot of work in understanding intracellular events, very ...few can come close to quantitation or semiquantitation in living cells. In this work, we made an effective use of nanomaterials, graphene oxides, both as a quencher and a carrier for intracellular delivery. In addition, this graphene oxide also serves as the carrier for reference probes for fluorescent imaging. An ATP aptamer molecular beacon (AAMB) is adsorbed on graphene oxide (GO) to form a double quenching platform. The AAMB/GO spontaneously enters cells, and then AAMB is released and opened by intracellular ATP. The resulting fluorescence recovery is used to perform ATP live-cell imaging with greatly improved background and signaling. Moreover, a control ssDNA, which is released nonspecifically from GO by nontarget cellular proteins, can serve as an internal reference for ATP semiquantification inside living cells using the intensity ratio of the AAMB and control. This approach can serve as a way for intracellular delivery and quantitative analysis.
Hollow particles have been extensively used in bioanalytical and biomedical applications for almost two decades due to their unique and tunable optoelectronic properties as well as their ...significantly high loading capacities. These intrinsic properties led them to be used in various bioimaging applications as contrast agents, controlled delivery (i.e. drugs, nucleic acids and other biomolecules) platforms and photon-triggered therapies (e.g. photothermal and photodynamic therapies). Since recent studies showed that imaging-guided targeted therapeutics have higher success rates, multimodal theranostic platforms (combination of one or more therapy and diagnosis modality) have been employed more often and hollow particles (i.e. nanoshells) have been one of the most efficient candidates to be used in multiple-purpose platforms, owing to their intrinsic properties that enable synergistic multimodal performance. In this review, recent advances in the applications of such hollow particles fabricated with various routes (either inorganic or organic based) were summarized to delineate strategies for tuning their properties for more efficient biomedical performance by overcoming common biological barriers. This review will pave the ways for expedited progress in design of next generation of hollow particles for clinical applications.
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•Hollow particles have unique and tunable optoelectronic properties with high loading capacities for multimodal therapeutics.•Their tunable physical structures and so their optoelectronic properties are suitable for different bioimaging modalities.•Imaging-guided targeted therapeutics demonstrated higher success rates so multimodal theranostic platforms are desired are amore.•The theranostic applications and surface modifications of hollow particles fabricated with various routes were summarized.
Plasmonic near-field coupling can induce the enhancement of photoresponsive processes by metal nanoparticles. Advances in nanostructured metal synthesis and theoretical modeling have kept surface ...plasmons in the spotlight. Previous efforts have resulted in significant intensity enhancement of organic dyes and quantum dots and increased absorption efficiency of optical materials used in solar cells. Here, we report that silver nanostructures can enhance the conversion efficiency of an interesting type of photosensitive DNA nanomotor through coupling with incorporated azobenzene moieties. Spectral overlap between the azobenzene absorption band and plasmonic resonances of silver nanowires increases light absorption of photon-sensitive DNA motor molecules, leading to 85% close-open conversion efficiency. The experimental results are consistent with our theoretical calculations of the electric field distribution. This enhanced conversion of DNA nanomotors holds promise for the development of new types of molecular nanodevices for light manipulative processes and solar energy harvesting.
Recent studies showed that imaging-guided cancer therapeutics have higher success rates so instead of using a single modality, the combination of diagnosis and therapy (theranostic) modalities have ...simultaneously been employed more often for the cancer treatments. Also, instead of employing single modality, combination of more than one modality for each cancer diagnosis and therapy becomes to be the route for the scientists study in the field of theranostics and applied nanotechnology due to the improved theranostic efficiency. Purpose-oriented fabricated nanoparticles are usually chosen as carriers and contrast agents for those multimodal theranostic systems owing to their unique optoelectronic (optical-electronic) and physical properties. This is a mini review as a general synopsis of the recent applications of nanoparticles as one of the most efficient cancer theranostic agents and future insights for theranostics.
Through the developments in controlling the shape of gold nanoparticles, synthesis of gold nanorods (AuNRs) can be considered as a milestone discovery in the area of nanomaterial-based cancer ...treatments. Besides having tuneable absorption maxima at near infrared (NIR) range, AuNRs have superior absorption cross section at NIR frequencies compared with other gold nanoparticles. When this unique optical property is combined with the specificity against cancer cells used by affinity tag conjugations, AuNRs become one of the most important nanoparticles used in both cancer cell sensing and in therapy. In this review, the impact of size and shape control of nanoparticles, especially AuNRs, on cancer cell treatments and a range of aptamer-conjugated AuNR applications in this regard are reviewed.
The development of multidrug resistance (MDR) has become an increasingly serious problem in cancer therapy. The cell-membrane overexpression of P-glycoprotein (P-gp), which can actively efflux ...various anticancer drugs from the cell, is a major mechanism of MDR. Nuclear-uptake nanodrug delivery systems, which enable intranuclear release of anticancer drugs, are expected to address this challenge by bypassing P-gp. However, before entering the nucleus, the nanocarrier must pass through the cell membrane, necessitating coordination between intracellular and intranuclear delivery. To accommodate this requirement, we have used DNA self-assembly to develop a nuclear-uptake nanodrug system carried by a cell-targeted near-infrared (NIR)-responsive nanotruck for drug-resistant cancer therapy. Via DNA hybridization, small drug-loaded gold nanoparticles (termed nanodrugs) can self-assemble onto the side face of a silver–gold nanorod (NR, termed nanotruck) whose end faces were modified with a cell type-specific internalizing aptamer. By using this size-photocontrollable nanodrug delivery system, anticancer drugs can be efficiently accumulated in the nuclei to effectively kill the cancer cells.
The development of nanomaterials that combine diagnostic and therapeutic functions within a single nanoplatform is extremely important for molecular medicine. Molecular imaging with simultaneous ...diagnosis and therapy will provide the multimodality needed for accurate diagnosis and targeted therapy. Here, gold‐coated iron oxide (Fe3O4@Au) nanoroses with five distinct functions are demonstrated, integrating aptamer‐based targeting, magnetic resonance imaging (MRI), optical imaging, photothermal therapy. and chemotherapy into one single probe. The inner Fe3O4 core functions as an MRI agent, while the photothermal effect is achieved through near‐infrared absorption by the gold shell, causing a rapid rise in temperature and also resulting in a facilitated release of the anticancer drug doxorubicin carried by the nanoroses. Where the doxorubicin is released, it is monitored by its fluorescence. Aptamers immobilized on the surfaces of the nanoroses enable efficient and selective drug delivery, imaging, and photothermal effect with high specificity. The five‐function‐embedded nanoroses show great advantages in multimodality.
Five functions in one probe: A gold‐coated iron oxide (Fe3O4@Au) nanorose with five distinct functions, which integrate aptamer‐based targeting, magnetic resonance imaging (MRI), optical imaging, photothermal and chemotherapy into one single probe is developed. This multifunctional nanoplatform is used for cancer cell targeting, dual molecular imaging, and dual therapy, with enhanced specific binding, improved cellular uptake, minimum nonspecific toxicity, and side effects.
The development of nanomaterials that combine diagnostic and therapeutic functions within a single nanoplatform is extremely important for molecular medicine. Molecular imaging with simultaneous ...diagnosis and therapy will provide the multimodality needed for accurate diagnosis and targeted therapy. Here, we demonstrate gold-coated iron oxide (Fe
O
@Au) nanoroses with five distinct functions, which integrate aptamer-based targeting, magnetic resonance imaging (MRI), optical imaging, photothermal therapy and chemotherapy into one single probe. The inner Fe
O
core functions as an MRI agent, while the photothermal effect is achieved through near-infrared absorption by the gold shell, causing a rapid rise in temperature and also resulting in a facilitated release of the anticancer drug doxorubicin carried by the nanoroses. Where the doxorubicin is released is monitored by its fluorescent. Aptamers immobilized on the surfaces of the nanoroses enable efficient and selective drug delivery, imaging and photothermal effect with high specificity. The five-function-embedded nanoroses show great advantages in multimodality.
This study demonstrates the use of aptamer-conjugated graphene oxide as an affinity extraction and detection platform for analytes from complex biological media. We have shown that cocaine and ...adenosine can be selectively enriched from plasma samples and that direct mass spectrometric readouts can be obtained without a matrix and with greatly improved signal-to-noise ratios. Aptamer-conjugated graphene oxide has clear advantages in target enrichment and in generating highly efficient ionization of target molecules for mass spectrometry. These results demonstrate the utility of the approach for analysis of small molecules in real biological samples.
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