Mesoporous Silica Nanoparticles Capped with Graphene Quantum Dots for Potential Chemo-Photothermal Synergistic Cancer Therapy

A comprehensive review on overcoming the multifaceted challenge of cancer multidrug resistance: The emerging role of mesoporous silica nanoparticles

Multidrug resistance (MDR) is a significant challenge in tumor treatment, severely reducing the effectiveness of anticancer drugs and contributing to high mortality rates. This article overviews the various factors involved in the development of MDR, such as changes in drug targets, increased DNA repair mechanisms, and the impact of the tumor microenvironment. It also emphasizes the potential of mesoporous silica nanoparticles (MSNs) as a drug delivery system to combat MDR. With their unique characteristics-such as a high surface area, adjustable pore sizes, and the ability to be functionalized for targeted delivery-MSNs serve as excellent carriers for the simultaneous delivery of chemotherapeutics and siRNAs aimed at reversing resistance pathways. The paper focuses on innovative methods using MSNs for direct intranuclear delivery of their cargos to overcome efflux barrier and improve the effectiveness of combination therapies. This review highlights a promising approach for enhancing cancer treatment outcomes by integrating advanced nanotechnology with traditional therapies, addressing the ongoing challenge of MDR in oncology.

Progress on Carbon Dots with Intrinsic Bioactivities for Multimodal Theranostics

Carbon dots (CDs) with intrinsic bioactivities are candidates for bioimaging and disease therapy due to their diverse bioactivities, high biocompatibility, and multiple functionalities in multimodal theranostics. It is a multidisciplinary research hotspot that includes biology, physics, materials science, and chemistry. This progress report discusses the CDs with intrinsic bioactivities and their applications in multimodal theranostics. The relationship between the synthesis and structure of CDs is summarized and analyzed from a material and chemical perspective. The bioactivities of CDs including anti-tumor, antibacterial, anti-inflammatory etc. are discussed from biological points of view. Subsequently, the optical and electronic properties of CDs that can be applied in the biomedical field are summarized from a physical perspective. Based on the functional review of CDs, their applications in the biomedical field are reviewed, including optical diagnosis and treatment, biological activity, etc. Unlike previous reviews, this review combines multiple disciplines to gain a more comprehensive understanding of the mechanisms, functions, and applications of CDs with intrinsic bioactivities.

Nano-therapeutics: The upcoming nanomedicine to treat cancer

Nanotechnology is considered a successful approach for cancer diagnosis and treatment. Preferentially, cancer cell recognition and drug targeting via nano-delivery system include the penetration of anticancer agents into the cell membrane to damage the cancer cell by protein modification, DNA oxidation, or mitochondrial dysfunction. The past research on nano-delivery systems and their target has proven the beneficial achievement in a malignant tumor. Modern perceptions using inventive nanomaterials for cancer management have been offered by a multifunctional platform based on various nano-carriers with the probability of imaging and cancer therapy simultaneously. Emerging nano-delivery systems in cancer therapy still lack knowledge of the biological functions behind the interaction between nanoparticles and cancer cells. Since the potential of engineered nanoparticles addresses the various challenges, limiting the success of cancer therapy subsequently, it is a must to review the molecular targeting of a nano-delivery system to enhance the therapeutic efficacy of cancer. This review focuses on using a nano-delivery system, an imaging system, and encapsulated nanoparticles for cancer therapy.

Innovative approaches for cancer treatment: graphene quantum dots for photodynamic and photothermal therapies

Graphene quantum dots (GQDs) hold great promise for photodynamic and photothermal cancer therapies. Their unique properties, such as exceptional photoluminescence, photothermal conversion efficiency, and surface functionalization capabilities, make them attractive candidates for targeted cancer treatment. GQDs have a high photothermal conversion efficiency, meaning they can efficiently convert light energy into heat, leading to localized hyperthermia in tumors. By targeting the tumor site with laser irradiation, GQD-based nanosystems can induce selective cancer cell destruction while sparing healthy tissues. In photodynamic therapy, light-sensitive compounds known as photosensitizers are activated by light of specific wavelengths, generating reactive oxygen species that induce cancer cell death. GQD-based nanosystems can act as excellent photosensitizers due to their ability to absorb light across a broad spectrum; their nanoscale size allows for deeper tissue penetration, enhancing the therapeutic effect. The combination of photothermal and photodynamic therapies using GQDs holds immense potential in cancer treatment. By integrating GQDs into this combination therapy approach, researchers aim to achieve enhanced therapeutic efficacy through synergistic effects. However, biodistribution and biodegradation of GQDs within the body present a significant hurdle to overcome, as ensuring their effective delivery to the tumor site and stability during treatment is crucial for therapeutic efficacy. In addition, achieving precise targeting specificity of GQDs to cancer cells is a challenging task that requires further exploration. Moreover, improving the photothermal conversion efficiency of GQDs, controlling reactive oxygen species generation for photodynamic therapy, and evaluating their long-term biocompatibility are all areas that demand attention. Scalability and cost-effectiveness of GQD synthesis methods, as well as obtaining regulatory approval for clinical applications, are also hurdles that need to be addressed. Further exploration of GQDs in photothermal and photodynamic cancer therapies holds promise for advancements in targeted drug delivery, personalized medicine approaches, and the development of innovative combination therapies. The purpose of this review is to critically examine the current trends and advancements in the application of GQDs in photothermal and photodynamic cancer therapies, highlighting their potential benefits, advantages, and future perspectives as well as addressing the crucial challenges that need to be overcome for their practical application in targeted cancer therapy.

Inorganic nanoparticles for photothermal treatment of cancer

In recent years, inorganic nanoparticles (NPs) have attracted increasing attention as potential theranostic agents in the field of oncology. Photothermal therapy (PTT) is a minimally invasive technique that uses nanoparticles to produce heat from light to kill cancer cells. PTT requires two essential elements: a photothermal agent (PTA) and near-infrared (NIR) radiation. The role of PTAs is to absorb NIR, which subsequently triggers hyperthermia within cancer cells. By raising the temperature in the tumor microenvironment (TME), PTT causes damage to the cancer cells. Nanoparticles (NPs) are instrumental in PTT given that they facilitate the passive and active targeting of the PTA to the TME, making them crucial for the effectiveness of the treatment. In addition, specific targeting can be achieved through their enhanced permeation and retention effect. Thus, owing to their significant advantages, such as altering the morphology and surface characteristics of nanocarriers comprised of PTA, NPs have been exploited to facilitate tumor regression significantly. This review highlights the properties of PTAs, the mechanism of PTT, and the results obtained from the improved curative efficacy of PTT by utilizing NPs platforms.

Photothermal therapy using graphene quantum dots

The rapid development of powerful anti-oncology medicines have been possible because of advances in nanomedicine. Photothermal therapy (PTT) is a type of treatment wherein nanomaterials absorb the laser energy and convert it into localized heat, thereby causing apoptosis and tumor eradication. PTT is more precise, less hazardous, and easy-to-control in comparison to other interventions such as chemotherapy, photodynamic therapy, and radiation therapy. Over the past decade, various nanomaterials for PTT applications have been reviewed; however, a comprehensive study of graphene quantum dots (GQDs) has been scantly reported. GQDs have received huge attention in healthcare technologies owing to their various excellent properties, such as high water solubility, chemical stability, good biocompatibility, and low toxicity. Motivated by the fascinating scientific discoveries and promising contributions of GQDs to the field of biomedicine, we present a comprehensive overview of recent progress in GQDs for PTT. This review summarizes the properties and synthesis strategies of GQDs including top-down and bottom-up approaches followed by their applications in PTT (alone and in combination with other treatment modalities such as chemotherapy, photodynamic therapy, immunotherapy, and radiotherapy). Furthermore, we also focus on the systematic study of in vitro and in vivo toxicities of GQDs triggered by PTT. Moreover, an overview of PTT along with the synergetic application used with GQDs for tumor eradication are discussed in detail. Finally, directions, possibilities, and limitations are described to encourage more research, which will lead to new treatments and better health care and bring people closer to the peak of human well-being.

Synergistic effect of polymer functionalized graphene oxide system for breast cancer treatment

The multifaceted drug carrier system is an emerging trend in delivering chemotherapeutic drugs and photosensitizers for the synergistic effect. In this work, we have designed a functionalized graphene oxide (GO) based carrier system for combined chemo-photodynamic therapeutic effects. Doxorubicin (DOX) and rose bengal (RB) were entrapped on the surface of GO via hydrophobic and π-π stacking interactions. The functional group determination, crystalline properties, surface morphology, and hydrodynamic size were evaluated using FT-IR, XRD, SEM, TEM, AFM, and DLS analysis. At 24 h, the entrapment efficiency was 65 % DOX and 40.92 % RB, and the loading capacities were 16.9 % DOX and 5.68 % RB observed at 30 min. The drug release percentage was higher in pH-2.6 rather than in pH-5.5, 6.8, and 7.4 pH environments. The in-vitro toxicity analysis using the LDH assay reveals that the DOX and RB co-loaded carriers had a significant cytotoxic effect on MCF-7 cells, indicating that the carrier could improve the therapeutic efficacy of DOX. Morphological changes were studied using inverted light microscopy; the cells were irradiated with a laser 525 nm 10 J/cm² for 2 min 51 sec, and it was observed that the DOX and RB co-loaded carrier with laser-irradiated cells exposed the high-level morphological changes with the occurrence of apoptotic cell death. Compared to free DOX, the DOX/RB co-loaded carrier + laser had an efficient anticancer activity, as confirmed by DAPI staining cell uptake, flow cytometry, and intracellular ROS generation analysis. The DOX and RB co-loaded carrier clearly exhibits the RB-mediated photodynamic action on MCF-7 cells in response to external laser light irradiation. It permits an on-demand dual-payload release to trigger an instantaneous photodynamic and chemo treatment for cancer cell eradication. Finally, the ensuing dual-agent release is probable to successfully fight cancer via a synergistic effect.

Recent Advances in Mesoporous Silica Nanoparticle-Mediated Drug Delivery for Breast Cancer Treatment

Breast cancer (BC) currently occupies the second rank in cancer-related global female deaths. Although consistent awareness and improved diagnosis have reduced mortality in recent years, late diagnosis and resistant response still limit the therapeutic efficacy of chemotherapeutic drugs (CDs), leading to relapse with consequent invasion and metastasis. Treatment with CDs is indeed well-versed but it is badly curtailed with accompanying side effects and inadequacies of site-specific drug delivery. As a result, drug carriers ensuring stealth delivery and sustained drug release with improved pharmacokinetics and biodistribution are urgently needed. Core-shell mesoporous silica nanoparticles (MSNPs) have recently been a cornerstone in this context, attributed to their high surface area, low density, robust functionalization, high drug loading capacity, size-shape-controlled functioning, and homogeneous shell architecture, enabling stealth drug delivery. Recent interest in using MSNPs as drug delivery vehicles has been due to their functionalization and size-shape-driven versatilities. With such insights, this article focuses on the preparation methods and drug delivery mechanisms of MSNPs, before discussing their emerging utility in BC treatment. The information compiled herein could consolidate the database for using inorganic nanoparticles (NPs) as BC drug delivery vehicles in terms of design, application and resolving post-therapy complications.

Ultrasmall porphyrin-silica core-shell dots for enhanced fluorescence imaging-guided cancer photodynamic therapy

Clinically used small-molecular photosensitizers (PSs) for photodynamic therapy (PDT) share similar disadvantages, such as the lack of selectivity towards cancer cells, short blood circulation time, life-threatening phototoxicity, and low physiological solubility. To overcome such limitations, the present study capitalizes on the synthesis of ultra-small hydrophilic porphyrin-based silica nanoparticles (core-shell porphyrin-silica dots; PSDs) to enhance the treatment outcomes of cancer via PDT. These ultra-small PSDs, with a hydrodynamic diameter less than 7 nm, have an excellent aqueous solubility in water (porphyrin; TPPS3-NH2) and enhanced tumor accumulation therefore exhibiting enhanced fluorescence imaging-guided PDT in breast cancer cells. Besides ultra-small size, such PSDs also displayed an excellent biocompatibility and negligible dark cytotoxicity in vitro. Moreover, PSDs were also found to be stable in other physiological solutions as a function of time. The fluorescence imaging of porphyrin revealed a prolonged residence time of PSDs in tumor regions, reduced accumulation in vital organs, and rapid renal clearance upon intravenous injection. The in vivo study further revealed reduced tumor growth in 4T1 tumor-bearing bulb mice after laser irradiation explaining the excellent photodynamic therapeutic efficacy of ultra-small PSDs. Thus, ultrasmall hydrophilic PSDs combined with excellent imaging-guided therapeutic abilities and renal clearance behavior represent a promising platform for cancer imaging and therapy.

Development of Biodegradable GQDs-hMSNs for Fluorescence Imaging and Dual Cancer Treatment via Photodynamic Therapy and Drug Delivery

Recently, nano-based cancer therapeutics have been researched and developed, with some nanomaterials showing anticancer properties. When it comes to cancer treatment, graphene quantum dots (GQDs) contain the ability to generate ¹O₂, a reactive oxidative species (ROS), allowing for the synergistic imaging and photodynamic therapy (PDT) of cancer. However, due to their small particle size, GQDs struggle to remain in the target area for long periods of time in addition to being poor drug carriers. To address this limitation of GQDs, hollow mesoporous silica nanoparticles (hMSNs) have been extensively researched for drug delivery applications. This project investigates the utilization and combination of biomass-derived GQDs and Stöber silica hMSNs to make graphene quantum dots-hollow mesoporous silica nanoparticles (GQDs-hMSNs) for fluorescent imaging and dual treatment of cancer via drug delivery and photodynamic therapy (PDT). Although the addition of hMSNs made the newly synthesized nanoparticles slightly more toxic at higher concentrations, the GQDs-hMSNs displayed excellent drug delivery using fluorescein (FITC) as a mock drug, and PDT treatment by using the GQDs as a photosensitizer (PS). Additionally, the GQDs retained their fluorescence through the surface binding to hMSNs, allowing them to still be used for cell-labeling applications.

Research Progress of Photothermal Nanomaterials in Multimodal Tumor Therapy

The aggressive growth of cancer cells brings extreme challenges to cancer therapy while triggering the exploration of the application of multimodal therapy methods. Multimodal tumor therapy based on photothermal nanomaterials is a new technology to realize tumor cell thermal ablation through near-infrared light irradiation with a specific wavelength, which has the advantages of high efficiency, less adverse reactions, and effective inhibition of tumor metastasis compared with traditional treatment methods such as surgical resection, chemotherapy, and radiotherapy. Photothermal nanomaterials have gained increasing interest due to their potential applications, remarkable properties, and advantages for tumor therapy. In this review, recent advances and the common applications of photothermal nanomaterials in multimodal tumor therapy are summarized, with a focus on the different types of photothermal nanomaterials and their application in multimodal tumor therapy. Moreover, the challenges and future applications have also been speculated.

Organic quantum dots: An ultrasmall nanoplatform for cancer theranostics

Tumours are the second leading cause of death globally, generating alterations in biological interactions and, as a result, malfunctioning of crucial genetic traits. Technological advancements have made it possible to identify tumours at the cellular level, making transcriptional gene variations and other genetic variables more easily investigated. Standard chemotherapy is seen as a non-specific treatment that has the potential to destroy healthy cells while also causing systemic toxicity in individuals. As a result, developing new technologies has become a pressing necessity. QDs are semiconductor particles with diameters ranging from 2 to 10 nanometers. QDs have grabbed the interest of many researchers due to their unique characteristics, including compact size, large surface area, surface charges, and precise targeting. QD-based drug carriers are well known among the many nanocarriers. Using QDs as a delivery approach enhances solubility, lengthens retention time, and reduces the harmful effects of loaded medicines. Several varieties of quantum dots used in drug administration are discussed in this article, along with their chemical and physical characteristics and manufacturing methods. Furthermore, it discusses the role of QDs in biological, medicinal, and theranostic applications.

Graphene quantum dots: A review on the effect of synthesis parameters and theranostic applications

The rising demand for early-stage diagnosis of diseases such as cancer, diabetes, neurodegenerative can be met with the development of materials offering high sensitivity and specificity. Graphene quantum dots (GQDs) have been investigated extensively for theranostic applications owing to their superior photostability and high aqueous dispersibility. These are attractive for a range of biomedical applications as their physicochemical and optoelectronic properties can be tuned precisely. However, many aspects of these properties remain to be explored. In the present review, we have discussed the effect of synthetic parameters upon their physicochemical characteristics relevant to bioimaging. We have highlighted the effect of particle properties upon sensing of biological molecules through 'turn-on' and 'turn-off' fluorescence and generation of electrochemical signals. After describing the effect of surface chemistry and solution pH on optical properties, an inclusive view on application of GQDs in drug delivery and radiation therapy has been given. Finally, a brief overview on their application in gene therapy has also been included.

Functionalization of Nanoparticulate Drug Delivery Systems and Its Influence in Cancer Therapy

Research into the application of nanocarriers in the delivery of cancer-fighting drugs has been a promising research area for decades. On the other hand, their cytotoxic effects on cells, low uptake efficiency, and therapeutic resistance have limited their therapeutic use. However, the urgency of pressing healthcare needs has resulted in the functionalization of nanoparticles' (NPs) physicochemical properties to improve clinical outcomes of new, old, and repurposed drugs. This article reviews recent research on methods for targeting functionalized nanoparticles to the tumor microenvironment (TME). Additionally, the use of relevant engineering techniques for surface functionalization of nanocarriers (liposomes, dendrimers, and mesoporous silica) and their critical roles in overcoming the current limitations in cancer therapy-targeting ligands used for targeted delivery, stimuli strategies, and multifunctional nanoparticles-were all reviewed. The limitations and future perspectives of functionalized nanoparticles were also finally discussed. Using relevant keywords, published scientific literature from all credible sources was retrieved. A quick search of the literature yielded almost 400 publications. The subject matter of this review was addressed adequately using an inclusion/exclusion criterion. The content of this review provides a reasonable basis for further studies to fully exploit the potential of these nanoparticles in cancer therapy.

Application of Quercetin in the Treatment of Gastrointestinal Cancers

Many cellular signaling pathways contribute to the regulation of cell proliferation, division, motility, and apoptosis. Deregulation of these pathways contributes to tumor cell initiation and tumor progression. Lately, significant attention has been focused on the use of natural products as a promising strategy in cancer treatment. Quercetin is a natural flavonol compound widely present in commonly consumed foods. Quercetin has shown significant inhibitory effects on tumor progression via various mechanisms of action. These include stimulating cell cycle arrest or/and apoptosis as well as its antioxidant properties. Herein, we summarize the therapeutic effects of quercetin in gastrointestinal cancers (pancreatic, gastric, colorectal, esophageal, hepatocellular, and oral).

Advances in preparation, mechanism and applications of graphene quantum dots/semiconductor composite photocatalysts: A review

Due to the low efficiency of single-component nano materials, there are more and more studies on high-efficiency composites. As zero dimensional (0D) non-metallic semiconductor material, the emergence of graphene quantum dots (GQDs) overcomes the shortcomings of traditional photocatalysts (rapid rate of electron-hole recombination and narrow range of optical response). Their uniqueness is that they can combine the advantages of quantum dots (rich functional groups at edge) and sp² carbon materials (large specific surface area). The inherent inert carbon stabilizes chemical and physical properties, and brings new breakthroughs to the development of benchmark photocatalysts. The photocatalytic efficiency of GQDs composite with semiconductor materials (SCs) can be improved by the following three points: (1) accelerating charge transfer, (2) extending light absorption range, (3) increasing active sites. The methods of preparation (bottom-up and top-down), types of heterojunctions, mechanisms of photocatalysis, and applications of GQDs/SCs (wastewater treatment, energy storage, gas sensing, UV detection, antibiosis and biomedicine) are comprehensively discussed. And it is hoped that this review can provide some guidance for the future research on of GQDs/SCs on photocatalysis.

Bioactive Graphene Quantum Dots Based Polymer Composite for Biomedical Applications

Today, nanomedicine seeks to develop new polymer composites to overcome current problems in diagnosing and treating common diseases, especially cancer. To achieve this goal, research on polymer composites has expanded so that, in recent years, interdisciplinary collaborations between scientists have been expanding day by day. The synthesis and applications of bioactive GQD-based polymer composites have been investigated in medicine and biomedicine. Bioactive GQD-based polymer composites have a special role as drug delivery carriers. Bioactive GQDs are one of the newcomers to the list of carbon-based nanomaterials. In addition, the antibacterial and anti-diabetic potentials of bioactive GQDs are already known. Due to their highly specific surface properties, π-π aggregation, and hydrophobic interactions, bioactive GQD-based polymer composites have a high drug loading capacity, and, in case of proper correction, can be used as an excellent option for the release of anticancer drugs, gene carriers, biosensors, bioimaging, antibacterial applications, cell culture, and tissue engineering. In this paper, we summarize recent advances in using bioactive GQD-based polymer composites in drug delivery, gene delivery, thermal therapy, thermodynamic therapy, bioimaging, tissue engineering, bioactive GQD synthesis, and GQD green resuscitation, in addition to examining GQD-based polymer composites.

Smart Nanocarriers as an Emerging Platform for Cancer Therapy: A Review

Cancer is a group of disorders characterized by uncontrolled cell growth that affects around 11 million people each year globally. Nanocarrier-based systems are extensively used in cancer imaging, diagnostics as well as therapeutics; owing to their promising features and potential to augment therapeutic efficacy. The focal point of research remains to develop new-fangled smart nanocarriers that can selectively respond to cancer-specific conditions and deliver medications to target cells efficiently. Nanocarriers deliver loaded therapeutic cargos to the tumour site either in a passive or active mode, with the least drug elimination from the drug delivery systems. This review chiefly focuses on current advances allied to smart nanocarriers such as dendrimers, liposomes, mesoporous silica nanoparticles, quantum dots, micelles, superparamagnetic iron-oxide nanoparticles, gold nanoparticles and carbon nanotubes, to list a few. Exhaustive discussion on crucial topics like drug targeting, surface decorated smart-nanocarriers and stimuli-responsive cancer nanotherapeutics responding to temperature, enzyme, pH and redox stimuli have been covered.

Current trends in smart mesoporous silica-based nanovehicles for photoactivated cancer therapy

Photoactivated therapeutic strategies (photothermal therapy and photodynamic therapy), due to the adjusted therapeutic area, time and light dosage, have prevailed for the fight against tumors. Currently, the monotherapy with limited treatment effect and undesired side effects is gradually replaced by multimodal and multifunctional nanosystems. Mesoporous silica nanoparticles (MSNs) with unique physicochemical advantages, such as huge specific surface area, controllable pore size and morphology, functionalized modification, satisfying biocompatibility and biodegradability, are considered as promising candidates for multimodal photoactivated cancer therapy. Excitingly, the innovative nanoplatforms based on the mesoporous silica nanoparticles provide more and more effective treatment strategies and display excellent antitumor potential. Given the rapid development of antitumor strategies based on MSNs, this review summarizes the current progress in MSNs-based photoactivated cancer therapy, mainly consists of (1) photothermal therapy-related theranostics; (2) photodynamic therapy-related theranostics; (3) multimodal synergistic therapy, such as chemo-photothermal-photodynamic therapy, phototherapy-immunotherapy and phototherapy-radio therapy. Based on the limited penetration of irradiation light in photoactivated therapy, the challenges faced by deep-seated tumor therapy are fully discussed, and future clinical translation of MSNs-based photoactivated cancer therapy are highlighted.

Enhanced Photothermal Performance by Carbon Dot-Chelated Polydopamine Nanoparticles

Polydopamine (PDA) has been widely used in biomedical applications including imaging contrast agents, antioxidants, UV protection, and photothermal therapy due to its biocompatibility, metal-ion chelation, free-radical scavenging, and wideband absorption, but its low photothermal efficiency still needs to be improved. In this study, we chelated near-infrared (NIR) sensitive carbon quantum dots on the surface of polydopamine (PDA-PEI@N,S-CQDs) to increase its near-infrared absorption. Surprisingly, although only 4% (w/w) of carbon quantum dots was conjugated on the PDA surface, it still increased the photothermal efficiency by 30%. Moreover, PDA-PEI@N,S-CQDs could also be used as the drug carrier for loading 60% (w/w) of the DOX and achieved stimuli-responsive drug release under lysosomal pH (pH 5.0) and 808 nm laser illumination. For in vitro therapeutic experiment, PDA-PEI@N,S-CQDs showed the remarkable therapeutic performance under 808 nm laser irradiation for killing 90% of cancer cells compared with 50% by pure PDA nanoparticles, and the efficacy was even higher after loading DOX owing to the synergistic effect by photothermal therapy and chemotherapy. This intelligent and effective therapeutic nanosystem based on PDA-PEI@N,S-CQDs showed enhanced photothermal behavior after chelating carbon dots and promoted the future development of a nanoplatform for stimuli-responsive photothermal/chemo therapy.

Graphene and its derivatives: understanding the main chemical and medicinal chemistry roles for biomedical applications

Over the past few years, there has been a growing potential use of graphene and its derivatives in several biomedical areas, such as drug delivery systems, biosensors, and imaging systems, especially for having excellent optical, electronic, thermal, and mechanical properties. Therefore, nanomaterials in the graphene family have shown promising results in several areas of science. The different physicochemical properties of graphene and its derivatives guide its biocompatibility and toxicity. Hence, further studies to explain the interactions of these nanomaterials with biological systems are fundamental. This review has shown the applicability of the graphene family in several biomedical modalities, with particular attention for cancer therapy and diagnosis, as a potent theranostic. This ability is derivative from the considerable number of forms that the graphene family can assume. The graphene-based materials biodistribution profile, clearance, toxicity, and cytotoxicity, interacting with biological systems, are discussed here, focusing on its synthesis methodology, physicochemical properties, and production quality. Despite the growing increase in the bioavailability and toxicity studies of graphene and its derivatives, there is still much to be unveiled to develop safe and effective formulations.

Graphic abstract

Enhanced Photocatalytic Degradation of Methylene Blue by WO3 Nanoparticles Under NIR Light Irradiation

Photocatalysts have been paid great attention owing to their excellent performance in the degradation of dangerous organic pollutants. Herein, a novel longitudinally grown WO₃ photocatalyst was prepared by using a hydrothermal process, which had strong ultraviolet, visible light absorption, and weak near-infrared (NIR) absorption. The WO₃ photocatalyst exhibited excellent performance in the rapid degradation of methylene blue (MB) in industry. The photothermal effect is mainly responsible for the rapid degradation of MB under NIR laser irradiation. Besides, different morphologies and structures affect the degradation of MB. The longitudinally grown enlarged the contact area between photocatalyst and MB, and expanded the scope of the absorption wavelength of light, enhancing the stability of photocatalytic materials. So this unique transverse longitudinal structure exhibited a potential capability for degrading organic pollutants.

Fluorescence resonance energy transfer monitoring of pH-responsive doxorubicin release from carbon dots/aptamer functionalized magnetic mesoporous silica

Aim: To develop a novel theranostic nanoplatform for simultaneous fluorescent monitoring and stimuli-triggered drug delivery. Materials & methods: Different microscopic and spectroscopic techniques were used for the characterization of nanocarriers. MCF-7 and human umbilical vein endothelial cell lines were cultured and treated with different doses of doxorubicin-loaded nanocarriers. The cell viability and drug release were studied using MTT assay and fluorescence microscopy. Results: Biocompatible and mono-disperse nanocarriers represent hollow and mesoporous structures with the calculated surface area of 552.83 m².g^-1, high magnetic activity (12.6 emu.g^-1), appropriate colloidal stability and high drug loading capacity (up to 61%). Conclusion: Taxane-based carbon dots act as the pH-responsive gatekeepers for the controlled release of doxorubicin into cancer cells and provide a fluorescence resonance energy transfer system for real-time monitoring of drug delivery.

Ultrahigh Penetration and Retention of Graphene Quantum Dot Mesoporous Silica Nanohybrids for Image Guided Tumor Regression

So far, near-infrared (NIR) light responsive nanostructures have been well-defined in cancer nanomedicine. However, poor penetration and retention in tumors are the limiting factors. Here, we report the ultrahigh penetration and retention of carbanosilica (graphene quantum dots, GQDs embedded mesoporous silica) in solid tumors. After NIR light exposure, quick (0.5 h) emission from the tumor area is observed that is further retained up to a week (tested up to 10 days) with a single dose administration of nanohybrids. Emissive and photothermally active GQDs and porous silica shell (about 31% drug loading) make carbanosilica a promising nanotheranostic agent exhibiting 68.75% tumor shrinking compared to without NIR light exposure (34.48%). Generated heat (∼52 °C) alters the permeability of tumor enhancing the accumulation of nanotheranostics into the tumor environment. Successive tumor imaging ensures the prolonged follow-up of image guided tumor regression due to synergistic therapeutic effect of nanohybrids.

Theranostic Prospects of Graphene Quantum Dots in Breast Cancer

Breast cancer (BC) is increasing as a significant cause of mortality among women. In this context, early diagnosis and treatment strategies for BC are being developed by researchers at the cellular level using advanced nanomaterials. However, immaculate etiquette is the prerequisite for their implementation in clinical practice. Considering the stolid nature of cancer, combining diagnosis and therapy (theranostics) using graphene quantum dots (GQDs) is a prime focus and challenge for researchers. In a nutshell, GQDs is a new shining star among various fluorescent materials, which has acclaimed fame in a short duration in materials science and the biomedical field as well. From this perspective, we review various strategies in BC treatment using GQDs alone or in combination. In addition, the photophysical properties of GQDs explored in photothermal therapy, hyperthermia therapy, and photodynamic therapy are also discussed. Moreover, we also focus on the strategic use of GQDs both as drug carriers and as combinatorial-guided drug delivery motifs. This Review provides an update for the scientific community to plan and expand advanced theranostic horizons in BC using GQDs.

Mesoporous silica nanoparticles: synthesis methods and their therapeutic use-recent advances

Mesoporous silica nanoparticles (MSNPs) are a particular example of innovative nanomaterials for the development of drug delivery systems. MSNPs have recently received more attention for biological and pharmaceutical applications due to their capability to deliver therapeutic agents. Due to their unique structure, they can function as an effective carrier for the delivery of therapeutic agents to mitigate diseases progress, reduce inflammatory responses and consequently improve cancer treatment. The potency of MSNPs for the diagnosis and management of various diseases has been studied. This literature review will take an in-depth look into the properties of various types of MSNPs (e.g. shape, particle and pore size, surface area, pore volume and surface functionalisation), and discuss their characteristics, in terms of cellular uptake, drug delivery and release. MSNPs will then be discussed in terms of their therapeutic applications (passive and active tumour targeting, theranostics, biosensing and immunostimulative), biocompatibility and safety issues. Also, emerging trends and expected future advancements of this carrier will be provided.

Photo-responsive degradable hollow mesoporous organosilica nanoplatforms for drug delivery

BACKGROUND

Stimulus-responsive degradable mesoporous organosilica nanoparticles (MONs) have shown great promise as drug carriers via enhancing the efficiency of drug delivery and accelerating the degradation of nanocarriers. However, it remains a great challenge to develop novel light-enabled spatial and temporal degradable MONs with both superior responsiveness for efficient anti-cancer drug delivery and safe exocytosis.

RESULTS

We report a novel photo-responsive degradable hollow mesoporous organosilica nanoplatform (HMONs@GOQD). The platform is based on organosilica nanoparticles (HMONs) containing singlet oxygen (¹O₂)-responsive bridged organoalkoxysilanes and wrapped graphene oxide quantum dots (GOQDs). The unique hollow mesoporous structure of the HMONs guarantees an excellent drug loading and release profile. During light irradiation, ¹O₂ produced by the GOQDs leads to the degradation of the organosilica nanoparticles, resulting in enhanced local drug release.

CONCLUSIONS

We carried out in vitro and in vivo experiments using DOX as a model drug; DOX-HMONs@GOQDs exhibited high biocompatibility, accelerated degradation, and superior therapeutic efficacy during light irradiation, indicating a promising platform for clinical cancer therapy.

Synthesis of carbon-dots@SiO2@TiO2 nanoplatform for photothermal imaging induced multimodal synergistic antitumor

For facilitating theranostic nanoplatform with multimodal therapeutic ability, we develop the core-shell structured CDs@SiO2@TiO2 nanoplatforms (CST NPs). The designed CST NPs possess excellent photothermal effect and fluorescence resonance energy transfer (FRET) induced photodynamic property, which could achieve synergistic photothermal and photodynamic therapy. Meanwhile, the photothermal ability of CST NPs acts as a key role in the application of real-time photothermal imaging, benefitting for the diagnosis of tumor accurately. Moreover, the obtained CST NPs also exhibit outstanding sonodynamic effect with huge potential for sonodynamic therapy. Under the 650 nm laser irradiation, the synthesized CST NPs not only inhibit the growth of cancer cells in vitro, but also display precise photothermal imaging and photo-induced ablation to tumor in vivo. As a result, the prepared CST NPs may potentially serve as multifunctional nanoplatform for theranostic antitumor and pave the avenue for clinic cancer therapy.

Phototherapy with layered materials derived quantum dots

Quantum dots (QDs) originating from two-dimensional (2D) sheets of graphitic carbon nitride (g-C₃N₄), graphene, hexagonal boron nitride (h-BN), monoatomic buckled crystals (phosphorene), germanene, silicene and transition metal dichalcogenides (TMDCs) are emerging zero-dimensional materials. These QDs possess diverse optical properties, are chemically stable, have surprisingly excellent biocompatibility and are relatively amenable to surface modifications. It is therefore not difficult to see that these QDs have potential in a variety of bioapplications, including biosensing, bioimaging and anticancer and antimicrobial therapy. In this review, we briefly summarize the recent progress of these exciting QD based nanoagents and strategies for phototherapy. In addition, we will discuss about the current limitations, challenges and future prospects of QDs in biomedical applications.

A review of applications of principles of quantum physics in oncology: do quantum physics principles have any role in oncology research and applications?

Background:

Research in the applications of the principles of quantum physics in oncology has progressed significantly over the past decades; and several research groups with professionals from diverse scientific background, including electrical engineers, mathematicians, biologists, atomic physicists, computer programmers, and biochemists, are working collaboratively in an unprecedented and pioneering economic, organisational and human effort searching for a wider and more effective, potentially definitive, understanding of the cancers. It is hypothesised that the principles of quantum physics could open new and broader understanding of the cancers and the development of new effective, targeted, accurate, personalised and possibly definitive cancer treatment.

Materials and methods:

This paper reports on a review of recent studies in the field of the applications of the principles of quantum physics in biology, chemistry, biochemistry and quantum physics in cancer research, including quantum physics principles and cancer, quantum modelling techniques, quantum dots and its applications in oncology, quantum cascade laser histopathology and quantum computing applications.

Conclusions:

The applications of the principles of quantum physics in oncology, chemistry and biology are providing new perspectives and greater insights into a long-studied disease, which could result in a greater understanding of the cancers and the potential for personalised and definitive treatment methods.

Interfacial interaction of anesthetic lidocaine and mesoporous silica nanoparticles in aqueous solutions and its release properties

Lidocaine has been used as a local anesthetic by injection. The controlled release of lidocaine loaded into nanospheres is necessary to reduce the onset time of the anesthetic effect or increase the anesthetic analgesia duration. In this study, mesoporous silica nanoparticles (MSNs) with a large specific surface area were prepared by a sol-gel method, and the interfacial interaction between MSNs and lidocaine positively charged in aqueous solutions at different concentrations was investigated by adsorption tests, Fourier-transformed infrared spectroscopy, thermogravimetry-differential thermal analysis, and Brunauer-Emmett-Teller (BET) measurements. The electrostatic interaction between Si-OH on MSNs and lidocaine-NH⁺ was of importance for the adsorption phenomenon in aqueous solutions, indicating the monolayer adsorption of lidocaine. BET measurements also supported the decrease of pore volumes, and the hysteresis loop of the isotherm curve was not closed since the condensation of lidocaine in the mesopores formed micropores of less than 1.5 nm in size. The release profiles in phosphate buffered saline containing calcium and magnesium ions showed a rapid and higher release of lidocaine compared with that in phosphate buffered saline without divalent cations. The released lidocaine concentrations were sufficient for the expression of the anesthetic effect in dental anesthesia.

A near-infrared light-controlled smart nanocarrier with reversible polypeptide-engineered valve for targeted fluorescence-photoacoustic bimodal imaging-guided chemo-photothermal therapy

Despite burgeoning development of nanoplatform made in the past few years, it remains a challenge to produce drug nanocarrier that enables requested on/off drug release. Thus, this study aimed to develop an ideal near-infrared light-triggered smart nanocarrier for targeted imaging-guided treatment of cancer that tactfully integrated photothermal therapy with chemotherapy to accurately control drug release time and dosage. Methods: This delivery system was composed of Ag₂S QD coating with dendritic mesoporous silica (DMSN), which acted as nanocarrier of doxorubicin localized inside pores. To provide the nanocarrier with controlled release capability, a polypeptide-engineered that structure was reversible to photothermal effect of Ag₂S QD, was covalently grafted to the external surface of drug-loaded DMSN. Results: This nanocarrier with the size of 40~60 nm had satisfactory biocompatibility and photothermal conversion efficiency up to 28.35%. Due to acidity-triggered charge reversal of polypeptide, which significantly extended circulation time and improved targeting ability, fluorescence and photoacoustic signals were still obvious at tumor site post-24 h by tail vein injection and chemo-photothermal synergistic therapy obviously enhanced antitumor efficacy. Mild PTT with multiple short-term exposures not only reduced the side effect of overdose drug but also avoided skin damage caused by long-term irradiation. Conclusion: By adjusting irradiation time and on/off cycle, multiple small amount local drug release reduced the side effect of overdose drug and skin damage. This novel approach provided an ideal near-infrared light-triggered nanocarrier with accurate control of area, time, and especially dosage.

Hyaluronic Acid-Modified Porous Carbon-Coated Fe3O4 Nanoparticles for Magnetic Resonance Imaging-Guided Photothermal/Chemotherapy of Tumors

Chemotherapy is an effective method for treating cancer, clinically. However, side effects of drug and multidrug resistance restrict its application. In recent years, the combined treatment of chemotherapy and photothermal therapy (PTT) is becoming a promising method for treating cancer. PTT utilizes nanomaterials absorbing near-infrared light and producing heat to acquire advanced hyperthermia strategy for cancer treatment. Carbon nanomaterials with good biocompatibility, high surface area, and excellent photothermal properties are an excellent nanoplatform for drug delivery and PTT. Herein, porous carbon-coated magnetite nanoparticles (PCCMNs) were successfully synthesized by a one-pot solvothermal method. Magnetite, a contrast agent, can be used for magnetic resonance imaging. Hyaluronic acid was used to modify the PCCMNs to achieve targeted therapy. The obtained nanohybrid with a good photothermal effect can realize combined PTT/chemotherapy and will be a promising nanoplatform for high efficacy theranostics.

H2O2/near-infrared light-responsive nanotheronostics for MRI-guided synergistic chemo/photothermal cancer therapy

Aim: To develop a H₂O₂/near-infrared (NIR) laser light-responsive nanoplatform (manganese-doped Prussian blue@polypyrrole [MnPB@PPy]) for synergistic chemo/photothermal cancer theranostics. Materials & methods: Doxorubicin (DOX) was loaded onto the surface of polypyrrole shells. The in vitro and in vivo MRI performance and anticancer effects of these nanoparticles (NPs) were evaluated. Results: The MnPB@PPy NPs could not only generate heat under NIR laser irradiation for cancer photothermal therapy but also act as an excellent MRI contrast agent. The loaded DOX could be triggered to release by both NIR light and H₂O₂ to enhance synergistic therapeutic efficacy. The antitumor effects were confirmed by in vitro cellular cytotoxicity assays and in vivo treatment in a xenograft tumor model. Conclusion: The designed H₂O₂/NIR light-responsive MnPB@PPy-DOX NPs hold great potential for future biomedical applications.

Graphene quantum dots (GQDs)-based nanomaterials for improving photodynamic therapy in cancer treatment

Graphene quantum dots (GQDs) as novel nanomaterials, have received significant interest in the field of biomedical applications. It is worth noting that a large amount of research is devoted to GQDs-based nanocomposites for cancer treatment, especially for photodynamic therapy (PDT), in that they can act not only as more favorable photosensitizers (PSs) but also nanoplatforms for delivering PSs. In this review, the biological behavior and physicochemical properties of GQDs for PDT are described in detail, and the application of GQDs-based nanocomposites in improved PDT and PDT-based combination therapies is analyzed, which may provide a new strategy for designing efficient PDT systems for cancer treatment.

Quantum dot therapeutics: a new class of radical therapies

Traditional therapeutics and vaccines represent the bedrock of modern medicine, where isolated biochemical molecules or designed proteins have led to success in treating and preventing diseases. However, several adaptive pathogens, such as multidrug-resistant (MDR) superbugs, and rapidly evolving diseases, such as cancer, can evade such molecules very effectively. This poses an important problem since the rapid emergence of multidrug-resistance among microbes is one of the most pressing public health crises of our time-one that could claim more than 10 million lives and 100 trillion dollars annually by 2050. Several non-traditional antibiotics are now being developed that can survive in the face of adaptive drug resistance. One such versatile strategy is redox perturbation using quantum dot (QD) therapeutics. While redox molecules are nominally used by cells for intracellular signaling and other functions, specific generation of such species exogenously, using an electromagnetic stimulus (light, sound, magnetic field), can specifically kill the cells most vulnerable to such species. For example, recently QD therapeutics have shown tremendous promise by specifically generating superoxide intracellularly (using light as a trigger) to selectively eliminate a wide range of MDR pathogens. While the efficacy of such QD therapeutics was shown using in vitro studies, several apparent contradictions exist regarding QD safety and potential for clinical applications. In this review, we outline the design rules for creating specific QD therapies for redox perturbation; summarize the parameters for choosing appropriate materials, size, and capping ligands to ensure their facile clearance; and highlight a potential path forward towards developing this new class of radical QD therapeutics.