Milk-derived multi-fluorescent graphene quantum dot-based cancer theranostic system

Electrochemical synthesis of multicolor fluorescent N-doped graphene quantum dots as a ferric ion sensor and their application in bioimaging

A novel electrochemical strategy for simple and facile synthesis of semicarbazide functionalized nitrogen-doped graphene quantum dots (N-GQDs) was reported, based on direct exfoliation and oxidation from graphite rods.

A Systematic Review and Critical Analysis of the Role of Graphene-Based Nanomaterialsin Cancer Theranostics

Many graphene-based materials (GBNs) applied to therapy and diagnostics (theranostics) in cancer have been developed. Most of them are hybrid combinations of graphene with other components (e.g, drugs or other bioactives, polymers, and nanoparticles) aiming toward a synergic theranostic effect. However, the role of graphene in each of these hybrids is sometimes not clear enough and the synergic graphene effect is not proven. The objective of this review is to elaborate on the role of GBNs in the studies evaluated and to compare the nanoformulations in terms of some of their characteristics, such as therapeutic outcomes and toxicity, which are essential features for their potential use as bionanosystems. A systematic review was carried out using the following databases: PubMed, Scopus, and ISI Web of Science (2013⁻2018). Additional studies were identified manually by consulting the references list of relevant reviews. Only English papers presenting at least one strategy for cancer therapy and one strategy for cancer diagnostics, and that clearly show the role of graphene in theranostics, were included. Data extraction and quality assessment was made by reviewer pairings. Fifty-five studies met the inclusion criteria, but they were too heterogeneous to combine in statistical meta-analysis. Critical analysis and discussion of the selected papers are presented.

Tailoring Blue-Green Double Emissions in Carbon Quantum Dots via Co-Doping Engineering by Competition Mechanism between Chlorine-Related States and Conjugated π-Domains

Representing single-layer to tens of layers of graphene in a size less than 30 nm, carbon quantum dots (CQDs) is becoming an advanced multifunctional material for its unique optical, electronic, spin and photoelectric properties induced by the quantum confinement effect and edge effect. In present work, upon co-doping engineering, nitrogen and chlorine co-doped CQDs with uniquely strong blue-green double emissions are developed via a facile and one-pot hydrothermal method. The crystalline and optical properties of CQDs have been well manipulated by tuning the mole ratio of nitrogen/chlorine and the reaction time. The characteristic green emission centered at 512 nm has been verified, originating from the chlorine-related states, the other blue emissions centered at 460 nm are attributed to the conjugated π-domain. Increasing the proportion of 1,2,4-benzentriamine dihydrochloride can effectively adjust the bandgap of CQDs, mainly caused by the synergy and competition of chlorine-related states and the conjugated π-domain. Prolonging the reaction time promotes more nitrogen and chlorine dopants incorporate into CQDs, which inhibits the growth of CQDs to reduce the average size of CQDs down to 1.5 nm, so that the quantum confinement effect dominates into play. This work not only provides a candidate with excellent optical properties for heteroatoms-doped carbon materials but also benefits to stimulate the intensive studies for co-doped carbon with chlorine as one of new dopants paradigm.

Facile Synthesis of Fluorescent Hyper-Cross-Linked β-Cyclodextrin-Carbon Quantum Dot Hybrid Nanosponges for Tumor Theranostic Application with Enhanced Antitumor Efficacy

Fluorescent hyper-cross-linked β-cyclodextrin-carbon quantum dot (β-CD-CQD) hybrid nanosponges of about 200 nm with excellent biocompatibility and strong bright blue fluorescence excited at 365 nm with a high photoluminescence quantum yield (PLQY) of 38.0% were synthesized for tumor theranostic application by facile condensation polymerization of carbon quantum dots (CQDs) with β-cyclodextrin (β-CD) at a feeding ratio of 1:5. The DOX@β-CD-CQD theranostic nanomedicine, around 300 nm with DOX-loading capacity of 39.5% by loading doxorubicin (DOX) via host-guest complexation, showed a pH responsive controlled release and released DOX in the simulated tumor microenvironment in a sustained release mode, owing to the formation constant in the supramolecular complexation of DOX with the β-CD units in the β-CD-CQD nanosponges. The proposed DOX@β-CD-CQD theranostic nanomedicine could be internalized into HepG2 cells, and the released DOX was accumulated into the cell nuclei, demonstrating an antitumor efficacy more enhanced than that of the free drug.

Tuning Optoelectronic Properties of the Graphene-Based Quantum Dots C16- xSi xH10 Family

The electronic and optical properties of graphene-based quantum dots (QDs) are investigated using DFT and many-body perturbation theory. Formation energy, hardeness and electrophilicity show that all structures, from pyrene to silicene QD passing through 15 CSi QD configurations, are energetically and chemically stable. It is also found that they are reactive which implies their favorable character for the possible electronic transport and conductivity. The electronic and optical properties are very sensitive to the number and position of the substituted silicon atoms as well as the directions of the light polarization. Moreover, quantum confinement effects make the exciton binding energy of CSi quantum dots larger than those of their higher dimensional allotropes such as silicene, graphene, and SiC sheet and nanotube. It is also higher those of other shapes of quantum dots like hexagonal graphene QDs and can be tailored from the ultraviolet region to the visible one. The values of the singlet-triplet splitting determined for the X- and Y-light polarized indicate that all configurations have a high fluorescence quantum yield compared to the yield of typical semiconductors, which makes them very promising for various applications such as the light-emitting diode material and nanomedicine.

Big Potential from Small Agents: Nanoparticles for Imaging-Based Companion Diagnostics

The importance of medical imaging in the diagnosis and monitoring of cancer cannot be overstated. As personalized cancer treatments are gaining popularity, a need for more advanced imaging techniques has grown significantly. Nanoparticles are uniquely suited to fill this void, not only as imaging contrast agents but also as companion diagnostics. This review provides an overview of many ways nanoparticle imaging agents have contributed to cancer imaging, both preclinically and in the clinic, as well as charting future directions in companion diagnostics. We conclude that, while nanoparticle-based imaging agents are not without considerable scientific and developmental challenges, they enable enhanced imaging in nearly every modality, hold potential as in vivo companion diagnostics, and offer precise cancer treatment and maximize intervention efficacy.

Graphene Quantum Dots for Cell Proliferation, Nucleus Imaging, and Photoluminescent Sensing Applications

We report a simple one-pot microwave assisted "green synthesis" of Graphene Quantum Dots (GQDs) using grape seed extract as a green therapeutic carbon source. These GQDs readily self-assemble, hereafter referred to as "self-assembled" GQDs (sGQDs) in the aqueous medium. The sGQDs enter via caveolae and clathrin-mediated endocytosis and target themselves into cell nucleus within 6-8 h without additional assistance of external capping/targeting agent. The tendency to self-localize themselves into cell nucleus also remains consistent in different cell lines such as L929, HT-1080, MIA PaCa-2, HeLa, and MG-63 cells, thereby serving as a nucleus labelling agent. Furthermore, the sGQDs are highly biocompatible and act as an enhancer in cell proliferation in mouse fibroblasts as confirmed by in vitro wound scratch assay and cell cycle analysis. Also, photoluminescence property of sGQDs (lifetime circa (ca.) 10 ns) was used for optical pH sensing application. The sGQDs show linear, cyclic and reversible trend in its fluorescence intensity between pH 3 and pH 10 (response time: ~1 min, sensitivity -49.96 ± 3.5 mV/pH) thereby serving as a good pH sensing agent. A simple, cost-effective, scalable and green synthetic approach based sGQDs can be used to develop selective organelle labelling, nucleus targeting in theranostics, and optical sensing probes.

Nanoparticles as Theranostic Vehicles in Experimental and Clinical Applications-Focus on Prostate and Breast Cancer

Prostate and breast cancer are the second most and most commonly diagnosed cancer in men and women worldwide, respectively. The American Cancer Society estimates that during 2016 in the USA around 430,000 individuals were diagnosed with one of these two types of cancers, and approximately 15% of them will die from the disease. In Europe, the rate of incidences and deaths are similar to those in the USA. Several different more or less successful diagnostic and therapeutic approaches have been developed and evaluated in order to tackle this issue and thereby decrease the death rates. By using nanoparticles as vehicles carrying both diagnostic and therapeutic molecular entities, individualized targeted theranostic nanomedicine has emerged as a promising option to increase the sensitivity and the specificity during diagnosis, as well as the likelihood of survival or prolonged survival after therapy. This article presents and discusses important and promising different kinds of nanoparticles, as well as imaging and therapy options, suitable for theranostic applications. The presentation of different nanoparticles and theranostic applications is quite general, but there is a special focus on prostate cancer. Some references and aspects regarding breast cancer are however also presented and discussed. Finally, the prostate cancer case is presented in more detail regarding diagnosis, staging, recurrence, metastases, and treatment options available today, followed by possible ways to move forward applying theranostics for both prostate and breast cancer based on promising experiments performed until today.

Methotrexate-loaded nitrogen-doped graphene quantum dots nanocarriers as an efficient anticancer drug delivery system

Graphene quantum dots (GQDs) are new efficient nanomaterials used in therapeutic applications. In this study, blue fluorescent nitrogen-doped GQDs (N-GQDs) were synthesized by a hydrothermal method via pyrolisis of citric acid as the carbon source and urea as the nitrogen source. The existence of doped nitrogen in GQDs was confirmed by FTIR characterization. Here, for the first time, the N-GQDs were loaded with the anticancer drug, methotrexate (MTX), to prepare MTX-(N-GQDs) as an efficient drug delivery system. The establishment of the strong π-π stacking interaction between MTX and N-GQDs was confirmed by FTIR and UV-vis spectroscopies indicating successful loading of MTX to N-GQDs. The in-vitro cytotoxicity of MTX-(N-GQDs) on human breast cancer cells investigated through MTT assay suggested that the drug-free N-GQDs nanocarriers are highly biocompatible, whereas the MTX-loaded ones are more cytotoxic than the free MTX.

Chronic exposure to graphene-based nanomaterials induces behavioral deficits and neural damage in Caenorhabditis elegans

Nanomaterials of graphene and its derivatives have been widely applied in recent years, but whose impacts on the environment and health are still not well understood. In the present study, the potential adverse effects of graphite (G), graphite oxide nanoplatelets (GO) and graphene quantum dots (GQDs) on the motor nervous system were investigated using nematode Caenorhabditis elegans as the assay system. After being characterized using TEM, SEM, XPS and PLE, three nanomaterials were chronically exposed to C. elegans for 6 days. In total, 50-100 mg l^-1 GO caused a significant reduction in the survival rate, but G and GDDs showed low lethality on nematodes. After chronic exposure of sub-lethal dosages, three nanomaterials were observed to distribute primarily in the pharynx and intestine; but GQDs were widespread in nematode body. Three graphene-based nanomaterials resulted in significant declines in locomotor frequency of body bending, head thrashing and pharynx pumping. In addition, mean speed, bending angle-frequency and wavelength of the crawling movement were significantly reduced after exposure. Using transgenic nematodes, we found high concentrations of graphene-based nanomaterials induced down-expression of dat-1::GFP and eat-4::GFP, but no significant changes in unc-47::GFP. This indicates that graphene-based nanomaterials can lead to damages in the dopaminergic and glutamatergic neurons. The present data suggest that chronic exposure of graphene-based nanomaterials may cause neurotoxicity risks of inducing behavioral deficits and neural damage. These findings provide useful information to understand the toxicity and safe application of graphene-based nanomaterials. Copyright © 2017 John Wiley & Sons, Ltd.

Li+ activated nanohydroxyapatite doped with Eu3+ ions enhances proliferative activity and viability of human stem progenitor cells of adipose tissue and olfactory ensheathing cells. Further perspective of nHAP:Li+, Eu3+ application in theranostics

Spinal cord injuries (SCI) often require simultaneous regeneration of nerve tissue and bone. Hydroxyapatites are described as bioresorbable materials with proper biocompatibility and osteoconductivity, therefore its application for spinal surgery is considered. In this paper, we present repeatable method for developing nanocrystalline calcium hydroxyapatites structurally modified with Li⁺ ions (nHAP:Li⁺). Obtained biomaterials were profoundly characterized in terms of their physicochemical properties. Moreover, we have shown that nHAP:Li⁺ doped with europium (Eu³⁺) may serve as a theranostic agent, what additionally extend its potential usage for SCI treatment. The biocompatibility of nHAP:Li⁺ was determined using human olfactory ensheathing cells (hOECs) and adipose tissue-derived multipotent stromal cells (hASCs). Both population of cells are eagerly applied for cell-based therapies in SCI, mainly due to their paracrine activity. The extensive in vitro studies showed that nHAP:Li⁺ promotes the cells proliferation, viability and cell-cell interactions. Obtained results provides encouraging approach that may have potential application in regenerative medicine and that could fulfil the promise of personalized medicine - important in SCI treatment.

Bio-synthesis of peppermint leaf extract polyphenols capped nano-platinum and their in-vitro cytotoxicity towards colon cancer cell lines (HCT 116)

Bio-synthesis of Platinum nanoparticles (Pt NPs) was achieved using Mentha piperita (Peppermint) aqueous leaf extract. Further the ecofriendly synthesized Pt NPs were subjected for various characterization techniques. The characterization results inferred that the green synthesized Pt NPs were said to be in average particle size of 54.3nm. The particles are in spherical shape and it has been entrapped with secondary metabolites (Polyphenols). The polyphenols capped Pt NPs were screened for cytotoxicity against human colon cancer cell line (HCT 116). The results inferred that the ecofriendly synthesized Pt NPs decrease the viability of cancer cells at lower concentrations with IC₅₀ value of 20μg/mL.

Indocyanine Green Loaded Magnetic Carbon Nanoparticles for Near Infrared Fluorescence/Magnetic Resonance Dual-Modal Imaging and Photothermal Therapy of Tumor

Malignant tumor incidences have been rapidly rising recently and are becoming a serious threat to human health. Herein, a multifunctional cancer targeted theranostic nanoplatform is developed by in situ growth of iron oxide magnetic nanoparticles on carbon nanoparticles, and then loaded with fluorescent dye indocyanine green (ICG@MCNPs). The loading of ICG on the nanoplatform significantly improves its photostability, and hence facilitates long-term near-infrared fluorescence (NIRF) imaging and efficient photothermal therapy (PTT) of tumor. The in vivo NIRF imaging reveals that ICG@MCNPs can be targeted to the tumor site. Moreover, in vivo magnetic resonance imaging also confirmed the efficient accumulation of ICG@MCNPs in the tumor site. Inspiringly, the subsequent PTT of tumor-bearing mice is achieved, as evidenced by the complete ablation of the tumor and the recovery of the physiological indexes to normal levels. Benefitting from its low-cost, simple preparation, and excellent dual-modal imaging and therapy, the ICG@MCNPs-based theranostic nanoplatform holds great promise in tumor-targeted nanomedicine.

Recent advances in carbon based nanosystems for cancer theranostics

This review deals with four different types of carbon allotrope based nanosystems and summarizes the results of recent studies that are likely to have applications in cancer theranostics. We discuss the applications of these nanosystems for cancer imaging, drug delivery, hyperthermia, and PDT/TA/PA.

Multifunctional graphene quantum dots for combined photothermal and photodynamic therapy coupled with cancer cell tracking applications

An Indian fig tree serves as a green factory by providing withered leaves as a carbon source for graphene quantum dots synthesis. The quantum dots are multi-functional and have tremendous theranostic biomedical applications.

Optical techniques for cervical neoplasia detection

This paper provides an overview of the current research in the field of optical techniques for cervical neoplasia detection and covers a wide range of the existing and emerging technologies. Using colposcopy, a visual inspection of the uterine cervix with a colposcope (a binocular microscope with 3- to 15-fold magnification), has proven to be an efficient approach for the detection of invasive cancer. Nevertheless, the development of a reliable and cost-effective technique for the identification of precancerous lesions, confined to the epithelium (cervical intraepithelial neoplasia) still remains a challenging problem. It is known that even at early stages the neoplastic transformations of cervical tissue induce complex changes and modify both structural and biochemical properties of tissues. The different methods, including spectroscopic (diffuse reflectance spectroscopy, induced fluorescence and autofluorescence spectroscopy, Raman spectroscopy) and imaging techniques (confocal microscopy, optical coherence tomography, Mueller matrix imaging polarimetry, photoacoustic imaging), probe different tissue properties that may serve as optical biomarkers for diagnosis. Both the advantages and drawbacks of these techniques for the diagnosis of cervical precancerous lesions are discussed and compared.

Multifunctional theranostic Pluronic mixed micelles improve targeted photoactivity of Verteporfin in cancer cells

Nanotechnology development provides new strategies to treat cancer by integration of different treatment modalities in a single multifunctional nanoparticle. In this scenario, we applied the multifunctional Pluronic P123/F127 mixed micelles for Verteporfin-mediated photodynamic therapy in PC3 and MCF-7 cancer cells. Micelles functionalization aimed the targeted delivery by the insertion of biotin moiety on micelle surface and fluorescence image-based through rhodamine-B dye conjugation in the polymer chains. Multifunctional Pluronics formed spherical nanoparticulated micelles that efficiently encapsulated the photosensitizer Verteporfin maintaining its favorable photophysical properties. Lyophilized formulations were stable at least for 6months and readily reconstituted in aqueous media. The multifunctional micelles were stable in protein-rich media due to the dual Pluronic mixed micelles characteristic: high drug loading capacity provided by its micellar core and high kinetic stability due its biocompatible shell. Biotin surface functionalized micelles showed higher internalization rates due biotin-mediated endocytosis, as demonstrated by competitive cellular uptake studies. Rhodamine B-tagged micelles allowed monitoring cellular uptake and intracellular distribution of the formulations. Confocal microscopy studies demonstrated a larger intracellular distribution of the formulation and photosensitizer, which could drive Verteporfin to act on multiple cell sites. Formulations were not toxic in the dark condition, but showed high Verteporfin-induced phototoxicity against both cancer cell lines at low drug and light doses. These results point Verteporfin-loaded multifunctional micelles as a promising tool to further developments in photodynamic therapy of cancer.