Carbon dots are a carbonaceous nanomaterial that were discovered accidentally and are now drawing significant attention as a new quantum-sized fluorescent nanoparticle. Carbon dots are biocompatible, non-toxic, photostable, and easily functionalized with good photoluminescence and water solubility. Due to these unique properties, they are used broadly in live cell imaging, catalysis, electronics, biosensing, power, targeted drug delivery, and other biomedical applications. Here, we review the recent development of carbon dots in nanomedicine from their use in drug carriers to imaging agents to multifunctional theranostic systems. Finally, we discuss the challenges and views on next-generation carbon dot-based theranostics for clinical applications.

The quest for an ideal cancer treatment has led to the exploration of a variety of platforms to facilitate highly desirable and efficient drug delivery. As most anticancer drugs possess therapeutic potency to destroy tumor cells, there is a need to steer the compounds to their required sites using site-specific drug delivery vehicles. This has inspired the investigation of various natural particulates and biomaterials for the purpose. Bio-inspired platforms that directly mimic natural components in the body have demonstrated their ability to serve as one of the most versatile and innovative drug delivery systems in cancer therapy and diagnosis. The primary advantage of this innovation lies in the fundamental changes in systemic biodistribution that non-native drug delivery does not possess. This review will try to provide a comprehensive understanding and a succinct evaluation of various intelligent bio-inspired delivery platforms, which have become prominent in recent studies. Recent innovative examples and their advantages and limitations as well as future clinical potential will also be thoroughly discussed.

Mesoporous silica nanomaterials (MSNs) have made remarkable achievements and are being thought of by researchers as materials that can be used to effect great change in cancer therapies, gene delivery, and drug delivery because of their optically transparent properties, flexible size, functional surface, low toxicity profile, and very good drug loading competence. Mesoporous silica nanoparticles (MSNPs) show a very high loading capacity for therapeutic agents. It is well known that cancer is one of the most severe known medical conditions, characterized by cells that grow and spread rapidly. Thus, curtailing cancer is one of the greatest current challenges for scientists. Nanotechnology is an evolving field of study, encompassing medicine, engineering, and science, and it has evolved over the years with respect to cancer therapy. This review outlines the applications of mesoporous nanomaterials in the field of cancer theranostics, as well as drug and gene delivery. MSNs employed as therapeutic agents, as well as their importance and future prospects in the ensuing generation of cancer theranostics and drug and therapeutic gene delivery, are discussed herein. Thus, the use of mesoporous silica nanomaterials can be seen as using one stone to kill three birds.

The relevance of personalized medicine has inspired research for individually concerted diagnosis and therapy. Numerous efforts are devoted to designing drug particulates with capabilities of tumor penetrating and subcellular trafficking to concurrently discharge theranostics in response to multistimulations. In this study, a bioinspired particulate, formulated with whole components of native high-density lipoproteins (HDLs) and decorated with the tumor-penetrating peptide iRGD, is proposed to promote tumor penetration of HDLs (pHDLs) together with payloads. Specifically, paclitaxel (PTX), and the NIR fluorescent probe indocyanine green (ICG) are integrated into pHDLs (pHDL/PTX-ICG) for synergetic chemo-phototherapy. Inspired by lipoproteins, pHDLs are not only restored from naturally occurring materials but also possessed artificially endowed functions, leading to an enhanced cellular uptake, higher accumulation, and deep penetration into tumors without causing appreciable adverse effects, compared to reconstituted HDLs or lipid-based nanoparticles. After intravenous administration, pHDL/PTX-ICG performs a burst of intracellular drug release and imaging-guided precision chemo-phototherapy upon NIR irradiation that completely eradicates xenograft tumors. Neither recurrence nor significant toxicity is observed due to maneuvered regional photodynamic and photothermal therapy. Taken together, pHDL/PTX-ICG is proven to be a promising platform to achieve deep tumor penetration and imaging-guided chemo-phototherapy.

No abstract

The relevance of personalized medicine, aimed at a more individualized drug therapy, has inspired research into nano-based concerted diagnosis and therapeutics (theranostics). As the intention is to "kill two birds with one stone", scientists have already described the emerging concept as a treasured tailor for the future of cancer therapy, wherein the main idea is to design "smart" nanosystems to concurrently discharge both therapeutic and diagnostic roles. These nanosystems are expected to offer a relatively clearer view of the ingenious cellular trafficking pathway, in-situ diagnosis, and therapeutic efficacy. We herein present a detailed review of versatile nanosystems, with prominent examples of recently developed intelligent delivery strategies which have gained attention in the field of theranostics. These nanotheranostics include various mechanisms programmed in novel platforms to enable predetermined delivery of cargo to specific sites, as well as techniques to overcome the notable challenges involved in the efficacy of theranostics.

PurposeNimodipine (NMP) is a clinical dihydropyridine calcium antagonist. However, the clinical application of NMP is limited by poor water solubility and low oral bioavailability. To overcome these drawbacks, this study designed optimal NMP-incorporated nanostructured lipid carriers (NLCs).MethodsHigh-pressure homogenization was successfully applied to prepare NMP-NLC, and the nanoparticle morphology was observed by a transmission electron microscope. The existence form of NMP in NMP-NLC was investigated by powder X-ray diffraction, differential scanning calorimetry, and Fourier transform infrared spectroscopy, respectively. The in vitro release study was performed by the dialysis method, and in vivo studies including in situ intestinal perfusion and pharmacokinetics were investigated in rats with NMP detected by high-performance liquid chromatography.ResultsThe obtained NMP-NLC shared a spherical shape of ~70 nm with a smooth surface and high encapsulation efficiency of 86.8%±2.1%. Spectroscopy indicated that the drug was in an amorphous state. The NMP-NLC exhibited a sustained release and diverse release profiles under different release medium, which mimicked the physiological environment. Moreover, an in situ intestinal perfusion experiment revealed that NMP-NLC could be mainly absorbed by the small intestine. Remarkable improvements in Cmax and AUC0–∞ from NMP-NLC were obtained from pharmacokinetic experiments, and the relative bioavailability of NMP-loaded nanostructured lipid systems was 160.96% relative to NMP suspensions.ConclusionCollectively, the NLCs significantly enhanced the oral bioavailability of NMP and might provide a promising nanoplatform for hydrophobic drug delivery.

Nanoparticle‐based drug delivery has become one of the most popular approaches for maximising drug therapeutic potentials. With the notable improvements, a greater challenge hinges on the formulation of gasotransmitters with unique challenges that are not met in liquid and solid active ingredients. Gas molecules upon release from formulations for therapeutic purposes have not really been discussed extensively. Herein, we take a critical look at four key gasotransmitters, that is, carbon monoxide (CO), nitric oxide (NO), hydrogen sulphide (H2S) and sulphur dioxide (SO2), their possible modification into prodrugs known as gas‐releasing molecules (GRMs), and their release from GRMs. Different nanosystems and their mediatory roles for efficient shuttling, targeting and release of these therapeutic gases are also reviewed extensively. This review thoroughly looks at the diverse ways in which these GRM prodrugs in delivery nanosystems are designed to respond to intrinsic and extrinsic stimuli for sustained release. In this review, we seek to provide a succinct summary for the development of therapeutic gases into potent prodrugs that can be adapted in nanomedicine for potential clinical use.