Acid pH-activated glycol chitosan/fullerene nanogels for efficient tumor therapy

Shrimp Waste Upcycling: Unveiling the Potential of Polysaccharides, Proteins, Carotenoids, and Fatty Acids with Emphasis on Extraction Techniques and Bioactive Properties

Shrimp processing generates substantial waste, which is rich in valuable components such as polysaccharides, proteins, carotenoids, and fatty acids. This review provides a comprehensive overview of the valorization of shrimp waste, mainly shrimp shells, focusing on extraction methods, bioactivities, and potential applications of these bioactive compounds. Various extraction techniques, including chemical extraction, microbial fermentation, enzyme-assisted extraction, microwave-assisted extraction, ultrasound-assisted extraction, and pressurized techniques are discussed, highlighting their efficacy in isolating polysaccharides, proteins, carotenoids, and fatty acids from shrimp waste. Additionally, the bioactivities associated with these compounds, such as antioxidant, antimicrobial, anti-inflammatory, and antitumor properties, among others, are elucidated, underscoring their potential in pharmaceutical, nutraceutical, and cosmeceutical applications. Furthermore, the review explores current and potential utilization avenues for these bioactive compounds, emphasizing the importance of sustainable resource management and circular economy principles in maximizing the value of shrimp waste. Overall, this review paper aims to provide insights into the multifaceted aspects of shrimp waste valorization, offering valuable information for researchers, industries, and policymakers interested in sustainable resource utilization and waste-management strategies.

Exploring the current landscape of chitosan-based hybrid nanoplatforms as cancer theragnostic

In the last decade, investigators have put significant efforts to develop several diagnostic and therapeutic strategies against cancer. Many novel nanoplatforms, including lipidic, metallic, and inorganic nanocarriers, have shown massive potential at preclinical and clinical stages for cancer diagnosis and treatment. Each of these nano-systems is distinct with its own benefits and limitations. The need to overcome the limitations of single-component nano-systems, improve their morphological and biological features, and achieve multiple functionalities has resulted in the emergence of hybrid nanoparticles (HNPs). These HNPs integrate multicomponent nano-systems with diagnostic and therapeutic functions into a single nano-system serving as promising nanotools for cancer theragnostic applications. Chitosan (CS) being a mucoadhesive, biodegradable, and biocompatible biopolymer, has emerged as an essential element for the development of HNPs offering several advantages over conventional nanoparticles including pH-dependent drug delivery, sustained drug release, and enhanced nanoparticle stability. In addition, the free protonable amino groups in the CS backbone offer flexibility to its structure, making it easy for the modification and functionalization of CS, resulting in better drug targetability and cell uptake. This review discusses in detail the existing different oncology-directed CS-based HNPs including their morphological characteristics, in-vitro/in-vivo outcomes, toxicity concerns, hurdles in clinical translation, and future prospects.

Recent advances in chitosan-based materials; The synthesis, modifications and biomedical applications

The attention to polymer-based biomaterials, for instance, chitosan and its derivatives, as well as the techniques for using them in numerous scientific domains, is continuously rising. Chitosan is a decomposable naturally occurring polymeric material that is mostly obtained from seafood waste. Because of its special ecofriendly, biocompatible, non- toxic nature as well as antimicrobial properties, chitosan-based materials have received a lot of interest in the field of biomedical applications. The reactivity of chitosan is mainly because of the amino and hydroxyl groups in its composition, which makes it further fascinating for various uses, including biosensing, textile finishing, antimicrobial wound dressing, tissue engineering, bioimaging, gene, DNA and drug delivery and as a coating material for medical implants. This study is an overview of the different types of chitosan-based materials which now a days have been fabricated by applying different techniques and modifications that include etherification, esterification, crosslinking, graft copolymerization and o-acetylation etc. for hydroxyl groups' processes and acetylation, quaternization, Schiff's base reaction, and grafting for amino groups' reactions. Furthermore, this overview summarizes the literature from recent years related to the important applications of chitosan-based materials (i.e., thin films, nanocomposites or nanoparticles, sponges and hydrogels) in different biomedical applications.

An endophytic fungus, Penicillium simplicissimum conjugated with C60 fullerene for its potential antimitotic, anti-inflammatory, anticancer and photodegradation activities

In the present study, endophytic fungus, Penicillium simplicissimum isolated from Loranthus micranthus was used to analyze phytochemical studies by qualitative and GC-MS methods. The endophytic fungus P. simplicissimum yielded novel compound penisimplicissin identified through GC-MS studies. Further, P. simplicissimum was conjugated with C60 fullerene nanoparticles (Ps-FNPs) were verified using UV-vis spectra, XRD, FTIR, DLS, EDX and SEM. Ps-FNPs was confirmed using UV-visible spectra with a peak at 260 nm. The IR bands were recorded at 2085, 1428, 1181, 661, 652, 644, 628, and 604 cm-1. The Ps-FNPs treated cells showed a nucleolar shrinkage and cell arrest atprophase, binuclear and multinucleolar cells, a chromosomal bridge and diversion at anaphase was observed, whereas, chromosomal fragment and abnormal distribution at metaphase stage. The Ps-FNPs exhibited a noteworthy anticancer activity on lung cancer cell line H1975 through cytotoxicity. The cytotoxicity was induced by increasing caspase-3, 7, and 9 activities and also showed highest inhibition in xanthine oxidase and COX-II assay proved good anti-inflammatory activity. Ps-FNPs have been extensively studied for photocatalytic activity test against Rhodamine B, Methylene blue and nigrosine showed potential dye degradation in the presence of sunlight proved to be novel photocatalysts. With all the results recorded, Ps-FNPs also have a synergetic effect having on anti-mitotic, anticancer, anti-inflammation potential and photocatalytic degradation of dyes. Hence, the conjugated Ps-FNPs could be one of the potent nano-drug formulations in future. Thus, the present study gives a clear idea of the multifaceted therapeutic and photocatalytic applications.

Development of novel polymeric nanoagents and their potential in cancer diagnosis and therapy runing title: Polymeric nanoagents for cancer theranostics

Cancer has been one of the leading factors of death around the world. Cancer patients usually have low 5-year survival rates and poor life quality requiring substantial improvement. In clinic, the presenting diagnostic strategies lack sensitivity with only a small proportion of patients can be accurately identified. For diagnosed patients, most of them are at the advanced stages thus being delayed to receive treatment. Therefore, it is eager to investigate and develop highly effective and accurate techniques for cancer early diagnosis and individualized therapy. Various nanoplatforms are emerging as imaging agents and drug carriers for cancer theranostics recently. Novel polymeric nanoagents, as a potent exemplar, have extraordinary merits, such as good stability, high biosafety and high drug loading efficacy, showing the great prospect for cancer early diagnosis and precise treatment. Herein, we review the recent advances in novel polymeric nanoagents and elucidate their synthesis procedures. We further introduce the applications of novel polymeric nanoagents in cancer diagnosis, treatment, and theranostics, as well as associated challenges and prospects in this field.

Multifunctional stimuli-responsive hybrid nanogels for cancer therapy: Current status and challenges

With cancer research shifting focus to achieving multifunctionality in cancer treatment strategies, hybrid nanogels are making a rapid rise to the spotlight as novel, multifunctional, stimuli-responsive, and biocompatible cancer therapeutic strategies. They can possess cancer cell-specific cytotoxic effects themselves, carry drugs or enzymes that can produce cytotoxic effects, improve imaging modalities, and target tumor cells over normal cells. Hybrid nanogels bring together a wide range of desirable properties for cancer treatment such as stimuli-responsiveness, efficient loading and protection of molecules such as drugs or enzymes, and effective crossing of cellular barriers among other properties. Despite their promising abilities, hybrid nanogels are still far from being used in the clinic, and their available data remains relatively limited. However, many studies can be done to facilitate this clinical transition. This review is critically summarizing and analyzing the recent information and progress on the use of hybrid nanogels particularly inorganic nanoparticle-based and organic nanoparticle-based hybrid nanogels in the field of oncology and future directions to aid in transferring those results to the clinic. This work concludes that the future of hybrid nanogels is greatly impacted by therapeutic and non-therapeutic factors. Therapeutic factors include the lack of hemocompatibility studies, acute and chronic toxicological studies, and information on agglomeration capability and extent, tumor heterogeneity, interaction with proteins in physiological fluids, endocytosis-exocytosis, and toxicity of the nanogels' breakdown products. Non-therapeutic factors include the lack of clear regulatory guidelines and standardized assays, limitations of animal models, and difficulties associated with good manufacture practices (GMP).

Chemical Modification of Chitosan for Developing Cancer Nanotheranostics

Cancer is a worldwide public health issue that has not been conquered. Theranostics, the combination of a therapeutic drug and imaging agent in one formulation using nanomaterials, has been developed to better cure cancer in recent years. Although diverse biomaterials have been applied in cancer theranostics, chitosan (CS), a natural polysaccharide bearing easy modification sites with excellent biocompatibility and biodegradability, shows great potential for developing cancer nanotheranostics. In this review, we seek to describe the chemical functionalities of CS used in cancer theranostics and their synthesis methods. We also present recent discoveries and research progresses on how the CS functionalization could improve the delivery efficiency of CS-based nanotheranostics. Finally, we report several case studies about the application of CS-based nanotheranostics. This paper focuses on the strategies to construct CS-based theranostics systems via chemical routes and highlights their applications in cancer treatment, which can provide useful references for further studies.

Stimuli-responsive drug delivery systems for head and neck cancer therapy

Head and neck cancer (HNC) is among the most common malignancy that has a profound impact on human health and life quality. The treatment for HNC, especially for the advanced cancer is stage-dependent and in need of combined therapies. Various forms of adjuvant treatments such as chemotherapy, phototherapy, hyperthermia, gene therapy have been included in the HNC therapy. However, there are still restrictions with traditional administration such as limited in situ therapeutic effect, systemic toxicity, drug resistance, etc. In recent years, stimuli-responsive drug delivery systems (DDSs) have attracted the great attention in HNC therapy. These intelligent DDSs could respond to unique tumor microenvironment, external triggers or dual/multi stimulus with more specific drug delivery and release, leading to enhanced treatment efficiency and less reduced side effects. In this article, recent studies on stimuli-responsive DDSs for HNC therapy were summarized, which could respond to endogenous and exogenous triggers including pH, matrix metalloproteinases (MMPs), reactive oxygen species (ROS), redox condition, light, magnetic field and multi stimuli. Their therapeutic remarks, current limits and future prospect for these intelligent DDSs were discussed. Furthermore, multifunctional stimuli-responsive DDSs have also been reviewed. With the modification of drug carriers or co-loading with therapeutic agents. Those intelligent DDSs showed more biofunctions such as combined therapeutic effects or integration of diagnosis and treatment for HNC. It is believed that stimuli-responsive drug delivery systems showed great potential for future clinic translation and application for the treatment of HNC.

Recent Applications of Dual-Stimuli Responsive Chitosan Hydrogel Nanocomposites as Drug Delivery Tools

Polysaccharides are a versatile class of macromolecules that are involved in many biological interactions critical to life. They can be further modified for added functionality. Once derivatized, these polymers can exhibit new chemical properties that can be further optimized for applications in drug delivery, wound healing, sensor development and others. Chitosan, derived from the N-deacetylation of chitin, is one example of a polysaccharide that has been functionalized and used as a major component of polysaccharide biomaterials. In this brief review, we focus on one aspect of chitosan's utility, namely we discuss recent advances in dual-responsive chitosan hydrogel nanomaterials.

Recent advances of emerging green chitosan-based biomaterials with potential biomedical applications: A review

Chitosan is the most abundant natural biopolymer, after cellulose. It is mainly derived from the fungi, shrimp's shells, and exoskeleton of crustaceans, through the deacetylation of chitin. The ecological sustainability associated with its exercise and the flexibility of chitosan owing to its active functional hydroxyl and amino groups makes it a promising candidate for a wide range of applications through a variety of modifications. The biodegradability and biocompatibility of chitosan and its derivatives along with their various chemical functionalities make them promising carriers for pharmaceutical, nutritional, medicinal, environmental, agriculture, drug delivery, and biotechnology applications. The present work aims to provide a detailed and organized description of modified chitosan and its derivatives-based nanomaterials for biomedical applications. We addressed the biological and physicochemical benefits of nanocomposite materials made up of chitosan and its derivatives in various formulations, including improved physicochemical stability and cells/tissue interaction, controlled drug release, and increased bioavailability and efficacy in clinical practice. Moreover, several modification techniques and their effective utilization are also reviewed and collected in this review.

Tumor-Targeting Glycol Chitosan Nanoparticles for Cancer Heterogeneity

Nanomedicine is extensively employed for cancer treatment owing to its unique advantages over conventional drugs and imaging agents. This increased attention to nanomedicine, however, has not fully translated into clinical utilization and patient benefits due to issues associated with reticuloendothelial system clearance, tumor heterogeneity, and complexity of the tumor microenvironment. To address these challenges, efforts are being made to modify the design of nanomedicines, including optimization of their physiochemical properties, active targeting, and response to stimuli, but these studies are often performed independently. Combining favorable nanomedicine designs from individual studies may improve therapeutic outcomes, but, this is difficult to achieve as the effects of different designs are interconnected and often conflicting. Glycol chitosan nanoparticles (CNPs) are shown to accumulate in tumors, suggesting that this type of nanoparticle may constitute a good basis for the additional modification of nanoparticles. Here, multifunctional glycol CNPs designed to overcome multiple obstacles to their use are described and key factors influencing in vivo targeted delivery, targeting strategies, and interesting stimulus-responsive designs for improving cancer nanomedicine are discussed.

Natural Hydrogels Applied in Photodynamic Therapy

Natural hydrogels are three-dimensional (3D) water-retaining materials with a skeleton consisting of natural polymers, their derivatives or mixtures. Natural hydrogels can provide sustained or controlled drug release and possess some unique properties of natural polymers, such as biodegradability, biocompatibility and some additional functions, such as CD44 targeting of hyaluronic acid. Natural hydrogels can be used with photosensitizers (PSs) in photodynamic therapy (PDT) to increase the range of applications. In the current review, the pertinent design variables are discussed along with a description of the categories of natural hydrogels available for PDT.

Molecular Interpretation of Pharmaceuticals’ Adsorption on Carbon Nanomaterials: Theory Meets Experiments

The ability of carbon-based nanomaterials (CNM) to interact with a variety of pharmaceutical drugs can be exploited in many applications. In particular, they have been studied both as carriers for in vivo drug delivery and as sorbents for the treatment of water polluted by pharmaceuticals. In recent years, the large number of experimental studies was also assisted by computational work as a tool to provide understanding at molecular level of structural and thermodynamic aspects of adsorption processes. Quantum mechanical methods, especially based on density functional theory (DFT) and classical molecular dynamics (MD) simulations were mainly applied to study adsorption/release of various drugs. This review aims to compare results obtained by theory and experiments, focusing on the adsorption of three classes of compounds: (i) simple organic model molecules; (ii) antimicrobials; (iii) cytostatics. Generally, a good agreement between experimental data (e.g. energies of adsorption, spectroscopic properties, adsorption isotherms, type of interactions, emerged from this review) and theoretical results can be reached, provided that a selection of the correct level of theory is performed. Computational studies are shown to be a valuable tool for investigating such systems and ultimately provide useful insights to guide CNMs materials development and design.

Glycol Chitosan: A Water-Soluble Polymer for Cell Imaging and Drug Delivery

Glycol chitosan (GC), a water-soluble chitosan derivative with hydrophilic ethylene glycol branches, has both hydrophobic segments for the encapsulation of various drugs and reactive functional groups for facile chemical modifications. Over the past two decades, a variety of molecules have been physically encapsulated within or chemically conjugated with GC and its derivatives to construct a wide range of functional biomaterials. This review summarizes the recent advances of GC-based materials in cell surface labeling, multimodal tumor imaging, and encapsulation and delivery of drugs (including chemotherapeutics, photosensitizers, nucleic acids, and antimicrobial agents) for combating cancers and microbial infections. Besides, different strategies for GC modifications are also highlighted with the aim to shed light on how to endow GC and its derivatives with desirable properties for therapeutic purposes. In addition, we discuss both the promises and challenges of the GC-derived biomaterials.

Effect of pH-Responsive Charge-Conversional Polymer Coating to Cationic Reduced Graphene Oxide Nanostructures for Tumor Microenvironment-Targeted Drug Delivery Systems

Tumor tissue represents a slightly acidic pH condition compared to normal tissue due to the accumulation of lactic acids via anaerobic metabolism. In this work, pH-responsive charge-conversional polymer (poly(ethylene imine)-poly(l-lysine)-poly(l-glutamic acid), PKE polymer) was employed for endowing charge-conversional property and serum stability to poly(ethylene imine) conjugated reduced graphene oxide-based drug delivery system (PEI-rGO). Zeta-potential value of PEI-rGO coated with PK5E7 polymer (PK5E7(PEI-rGO)) was -10.9 mV at pH 7.4 and converted to 29.2 mV at pH 6.0, showing pH-responsive charge-conversional property. Sharp-edged plate morphology of PEI-rGO was transformed to spherical nanostructures with vague edges by PK5E7 coating. Size of PK5E7(PEI-rGO) was found to be smaller than that of PEI-rGO in the serum condition, showing its increased serum stability. Loaded doxorubicin (DOX) in PK5E7(PEI-rGO) could be released rapidly in lysosomal condition (pH 5.0, 5 mM glutathione). Furthermore, DOX-loaded PK5E7(PEI-rGO) showed enhanced anticancer activity in HeLa and A549 cells in the tumor microenvironment-mimicking condition (pH 6.0, serum), which would be mediated by non-specific cellular interaction with decorated serum proteins. These results indicate that the pH-responsive charge-conversional PKE polymer coating strategy of cationic rGO nanostructures possesses a potential for acidic tumor microenvironment-targeted drug delivery systems.

Smart Organic-Inorganic Nanogels for Activatable Theranostics

Intelligent polymeric nanogels, with the rationally designed stimuli-responsive drug delivery and controlled drug release, have attracted considerable attention as an ideal nanoplatform for activatable therapy. On the other hand, functional inorganic nanomaterials are widely used as medical imaging agents due to their unique magnetic or optical properties. The construction of stimuli-responsive polymeric nanogels incorporating with functional inorganic nanomaterials inherits the excellent properties of both polymers and inorganic nanomaterials, consequently, the resulted organic-inorganic hybrid nanogels naturally exhibit stimuli-responsive multi-functionalities for both imaging and therapy. In this review, we summarize the recent advances of stimuli-responsive organic-inorganic hybrid nanogels. Firstly, we discuss the physical and chemical methods thus far developed for the integration of polymeric nanogels and inorganic nanomaterials, and then we show the typical examples of activatable theranostic applications using organic-inorganic hybrid nanogels. In the end, the existing challenges and future directions are briefly discussed.

Microgels in biomaterials and nanomedicines

Microgels are colloidal particles with crosslinked polymer networks and dimensions ranging from tens of nanometers to micrometers. Specifically, smart microgels are fascinating capable of responding to biological signals in vivo or remote triggers and making the possible for applications in biomaterials and biomedicines. Therefore, how to fundamentally design microgels is an urgent problem to be solved. In this review, we put forward our important fundamental opinions on how to devise the intelligent microgels for cancer therapy, biosensing and biological lubrication. We focus on the design ideas instead of specific implementation process by employing reverse synthesis analysis to programme the microgels at the original stage. Moreover, special insights will be, for the first time, as far as we know, dedicated to the particles completely composed of DNA or proteins into microgel systems. These are discussed in detail in this review. We expect to give readers a broad overview of the design criteria and practical methodologies of microgels according to the application fields, as well as to propel the further developments of highly interesting concepts and materials.

Carbon-based hybrid nanogels: a synergistic nanoplatform for combined biosensing, bioimaging, and responsive drug delivery

Nanosized crosslinked polymer networks, named as nanogels, are playing an increasingly important role in a diverse range of applications by virtue of their porous structures, large surface area, good biocompatibility and responsiveness to internal and/or external chemico-physical stimuli. Recently, a variety of carbon nanomaterials, such as carbon quantum dots, graphene/graphene oxide nanosheets, fullerenes, carbon nanotubes, and nanodiamonds, have been embedded into responsive polymer nanogels, in order to integrate the unique electro-optical properties of carbon nanomaterials with the merits of nanogels into a single hybrid nanogel system for improvement of their applications in nanomedicine. A vast number of studies have been pursued to explore the applications of carbon-based hybrid nanogels in biomedical areas for biosensing, bioimaging, and smart drug carriers with combinatorial therapies and/or theranostic ability. New synthetic methods and structures have been developed to prepare carbon-based hybrid nanogels with versatile properties and functions. In this review, we summarize the latest developments and applications and address the future perspectives of these carbon-based hybrid nanogels in the biomedical field.

Hypocrellin B-loaded, folate-conjugated polymeric micelle for intraperitoneal targeting of ovarian cancer in vitro and in vivo

Photodynamic therapy (PDT) is considered an innovative and attractive modality to treat ovarian cancer. In the present study, a biodegradable polymer poly (ethylene glycol) (PEG)‐poly (lactic acid)(PLA)‐folate (FA‐PEG‐PLA) was prepared in order to synthesize an active‐targeting, water‐soluble and pharmacomodulated photosensitizer nanocarrier. Drug‐loading content, encapsulation efficiency, in vitro and in vivo release were characterized, in which hypocrellin B (HB)/FA‐PEG‐PLA micelles had a high encapsulation efficiency and much slower control release for drugs compared to free drugs (P < .05). To evaluate the targeting ability of the HB/FA‐PEG‐PLA micelles, a cellular uptake study in vitro was carried out, which showed significantly enhanced uptake of HB/FA‐PEG‐PLA micelles in SKOV3 (FR+) compared to A2780 cancer cells (FR−). The enhanced uptake of HB/FA‐PEG‐PLA micelles to cancer cells resulted in a more effective post‐PDT killing of SKOV3 cells compared to plain micelles and free drugs. Binding and uptake of HB/FA‐PEG‐PLA micelles by SKOV3 cells were also observed in vivo after ip injection of folate‐targeted micelles in tumor‐bearing ascitic ovarian cancer animals. Drug levels in ascitic tumor tissues were increased 20‐fold (P < .001), which underscored the effect of a regional therapy approach with folate targeting. Furthermore, the HB‐loaded micelles were mainly distributed in kidney and liver (the main clearance organs) in biodistribution. These results showed that our newly developed PDT photosensitizer HB/FA‐PEG‐PLA micelles have a high drug‐loading capacity, good biocompatibility, controlled drug release, and enhanced targeting and antitumor effect, which is a potential approach to future targeting ovarian cancer therapy.

Versatile Chemical Derivatizations to Design Glycol Chitosan-Based Drug Carriers

Glycol chitosan (GC) and its derivatives have been extensively investigated as safe and effective drug delivery carriers because of their unique physiochemical and biological properties. The reactive functional groups such as the amine and hydroxyl groups on the GC backbone allow for easy chemical modification with various chemical compounds (e.g., hydrophobic molecules, crosslinkers, and acid-sensitive and labile molecules), and the versatility in chemical modifications enables production of a wide range of GC-based drug carriers. This review summarizes the versatile chemical modification methods that can be used to design GC-based drug carriers and describes their recent applications in disease therapy.

Fullerenes in Biology and Medicine

Fullerenes and related carbon based derivatives have shown a growing relevance in biology and medicine, mainly due to the unique electronic and structural properties that make them excellent candidates for multiple functionalization. This review focuses on the most recent developments of fullerene derivatives for different biological applications.

The Potential of Stimuli-Responsive Nanogels in Drug and Active Molecule Delivery for Targeted Therapy

Nanogels (NGs) are currently under extensive investigation due to their unique properties, such as small particle size, high encapsulation efficiency and protection of active agents from degradation, which make them ideal candidates as drug delivery systems (DDS). Stimuli-responsive NGs are cross-linked nanoparticles (NPs), composed of polymers, natural, synthetic, or a combination thereof that can swell by absorption (uptake) of large amounts of solvent, but not dissolve due to the constituent structure of the polymeric network. NGs can undergo change from a polymeric solution (swell form) to a hard particle (collapsed form) in response to (i) physical stimuli such as temperature, ionic strength, magnetic or electric fields; (ii) chemical stimuli such as pH, ions, specific molecules or (iii) biochemical stimuli such as enzymatic substrates or affinity ligands. The interest in NGs comes from their multi-stimuli nature involving reversible phase transitions in response to changes in the external media in a faster way than macroscopic gels or hydrogels due to their nanometric size. NGs have a porous structure able to encapsulate small molecules such as drugs and genes, then releasing them by changing their volume when external stimuli are applied.

Recent advances in engineered chitosan-based nanogels for biomedical applications

Recent progress in the preparation and biomedical applications of engineered chitosan-based nanogels has been comprehensively reviewed.

C60@lysozyme: a new photosensitizing agent for photodynamic therapy

C₆₀@lysozyme showed significant visible light-induced singlet oxygen generation in a physiological environment, indicating the potential of this hybrid as an agent for photodynamic therapy.

Stimuli-responsive nanogel composites and their application in nanomedicine

Nanogels are nanosized crosslinked polymer networks capable of absorbing large quantities of water. Specifically, smart nanogels are interesting because of their ability to respond to biomedically relevant changes like pH, temperature, etc. In the last few decades, hybrid nanogels or composites have been developed to overcome the ever increasing demand for new materials in this field. In this context, a hybrid refers to nanogels combined with different polymers and/or with nanoparticles such as plasmonic, magnetic, and carbonaceous nanoparticles, among others. Research activities are focused nowadays on using multifunctional hybrid nanogels in nanomedicine, not only as drug carriers but also as imaging and theranostic agents. In this review, we will describe nanogels, particularly in the form of composites or hybrids applied in nanomedicine.

Composites of Polymer Hydrogels and Nanoparticulate Systems for Biomedical and Pharmaceutical Applications

Due to their unique structures and properties, three-dimensional hydrogels and nanostructured particles have been widely studied and shown a very high potential for medical, therapeutic and diagnostic applications. However, hydrogels and nanoparticulate systems have respective disadvantages that limit their widespread applications. Recently, the incorporation of nanostructured fillers into hydrogels has been developed as an innovative means for the creation of novel materials with diverse functionality in order to meet new challenges. In this review, the fundamentals of hydrogels and nanoparticles (NPs) were briefly discussed, and then we comprehensively summarized recent advances in the design, synthesis, functionalization and application of nanocomposite hydrogels with enhanced mechanical, biological and physicochemical properties. Moreover, the current challenges and future opportunities for the use of these promising materials in the biomedical sector, especially the nanocomposite hydrogels produced from hydrogels and polymeric NPs, are discussed.

Novel delivery approaches for cancer therapeutics

Currently, a majority of cancer treatment strategies are based on the removal of tumor mass mainly by surgery. Chemical and physical treatments such as chemo- and radiotherapies have also made a major contribution in inhibiting rapid growth of malignant cells. Furthermore, these approaches are often combined to enhance therapeutic indices. It is widely known that surgery, chemo- and radiotherapy also inhibit normal cells growth. In addition, these treatment modalities are associated with severe side effects and high toxicity which in turn lead to low quality of life. This review encompasses novel strategies for more effective chemotherapeutic delivery aiming to generate better prognosis. Currently, cancer treatment is a highly dynamic field and significant advances are being made in the development of novel cancer treatment strategies. In contrast to conventional cancer therapeutics, novel approaches such as ligand or receptor based targeting, triggered release, intracellular drug targeting, gene delivery, cancer stem cell therapy, magnetic drug targeting and ultrasound-mediated drug delivery, have added new modalities for cancer treatment. These approaches have led to selective detection of malignant cells leading to their eradication with minimal side effects. Lowering multi-drug resistance and involving influx transportation in targeted drug delivery to cancer cells can also contribute significantly in the therapeutic interventions in cancer.

IR 820 dye encapsulated in polycaprolactone glycol chitosan: Poloxamer blend nanoparticles for photo immunotherapy for breast cancer

In the present study, we have fabricated biocompatible and biodegradable monodisperse IR 820 encapsulated polycaprolactone (PCL) glycol chitosan (GC): Poloxamer blend nanoparticles (PP-IR NPs) for imaging and effective photo-immunotherapy. IR 820 has been used as an imaging and photothermal agent whereas glycol chitosan (GC) as an immunostimulatory agent. The combination of IR 820, poloxamer, and GC can be used effectively for photoimmunotherapy for cancer, drug-resistant and TNF-α resistant estrogen positive breast cancer. PP-IR NPs are stable in aqueous solution. The uniform size of 100-220 nm with a high zeta value of +38 ± 2 mV led them to accumulate in cancer cells. Laser treatment did not affect the morphology of PP-IR NPs as observed under the transmission electron microscope (TEM). In vitro cytotoxicity studies on MCF-7 cells showed enhanced toxicity upon laser treatment. Further, we validated the cell death by reactive oxygen species (ROS) production. Our studies thus showed that PP-IR NPs are effective in suppressing metastatic cancer as the combinational therapy leads to the formation of apoptotic bodies in MCF-7 cells.

Hoechst 33258–conjugated hyaluronated fullerene for efficient photodynamic tumor therapy and necrotic tumor targeting

In this study, we synthesized a Hoechst 33258–conjugated hyaluronated fullerene consisting of Hoechst 33258 (as a target moiety to detect necrotic tumor cells), hyaluronic acid (as a target polymer to bind the CD44 receptor overexpressed on the surface of tumor cells), and fullerene (as a photosensitizing agent). This conjugate self-assembled to form nanoparticles consisting of a hydrophilic block (Hoechst 33258 and hyaluronic acid) and a lipophilic block (fullerene). We utilized these nanoparticles to improve the antitumor efficacy via photodynamic tumor therapy. The HCT-116 cells that were damaged after the first photodynamic tumor therapy (using hyaluronated fullerene nanoparticles) were again targeted using Hoechst 33258–conjugated hyaluronated fullerene nanoparticles (detecting necrotic tissues). The experimental results revealed that the second photodynamic tumor therapy using Hoechst 33258–conjugated hyaluronated fullerene nanoparticles caused significant increases in the in vitro phototoxicity and the in vivo tumor inhibition, thereby suggesting their pharmaceutical potential for designing effective multiple photodynamic tumor therapy treatments.

IR 820 stabilized multifunctional polycaprolactone glycol chitosan composite nanoparticles for cancer therapy

Photothermal therapy has gained worldwide attention for its less painful, non invasive/minimally invasive, effective thermal ablation based therapy for cancer.

Glycol chitosan-based fluorescent theranostic nanoagents for cancer therapy

Theranostics is an integrated nanosystem that combines therapeutics with diagnostics in attempt to develop new personalized treatments with enhanced therapeutic efficacy and safety. As a promising therapeutic paradigm with cutting-edge technologies, theranostic agents are able to simultaneously deliver therapeutic drugs and diagnostic imaging agents and also monitor the response to therapy. Polymeric nanosystems have been intensively explored for biomedical applications to diagnose and treat various cancers. In recent years, glycol chitosan-based nanoagents have been developed as dual-purpose materials for simultaneous diagnosis and therapy. They have shown great potential in cancer therapies, such as chemotherapeutics and nucleic acid and photodynamic therapies. In this review, we summarize the recent progress and potential applications of glycol chitosan-based fluorescent theranostic nanoagents for cancer treatments and discuss their possible underlying mechanisms.

Tumor-targeting glycol chitosan nanoparticles as a platform delivery carrier in cancer diagnosis and therapy

A natural based polymer, chitosan has received widespread attention in drug delivery systems due to its valuable physicochemical and biological characteristics. In particular, hydrophobic moiety-conjugated glycol chitosan can form amphiphilic self-assembled glycol chitosan nanoparticles (GCNPs) and simultaneously encapsulate hydrophobic drug molecules inside their hydrophobic core. This GCNP-based drug delivery systems exhibit excellent tumor-homing efficacy, attributed to the long blood circulation and the enhanced permeability and retention effect; this tumor-targeting drug delivery results in improved therapeutic efficiency. In this review, we describe the requisite properties of GCNPs for cancer therapy as well as imaging for diagnosis, such as their basic characteristics, in vitro delivery efficiency and in vivo tumor-targeting ability.

The effect of amphiphilic polymers on the association, morphology and photophysical properties of hypocrellin coordination polymer/fullerene assemblies

Y³⁺–PyrHA/fullerene can form nanoparticles in the size range of 10–60 nm and exhibits a higher singlet oxygen quantum yield than Y³⁺–PyrHA and the corresponding fullerene in 1% P123 solution.