Intraperitoneal Administration of a Cisplatin-Loaded Nanogel through a Hybrid System Containing an Alginic Acid-Based Nanogel and an In Situ Cross-Linkable Hydrogel for Peritoneal Dissemination of Ovarian Cancer

Innovative landscapes in intraperitoneal therapy of ovarian cancer

Epithelial ovarian cancer is the most prevalent gynecological malignancy, characterized by high mortality rates due to its late-stage diagnosis and frequent recurrence. The current standard of care for ovarian cancer is a combination of debulking surgery followed by the conventional mode of chemotherapy. Despite significant advances in therapeutic modalities, the overall survival rate of EOC continues to be poor, mainly because low concentrations of the chemotherapeutics reach the peritoneum, which is the primary site of ovarian cancer, leading to disease relapse. Here, intraperitoneal chemotherapy gains advantage due to its ability to deliver the drug molecules directly to the peritoneal cavity and provide localized and sustained effects. This is facilitated by the use of diverse kinds of nano or micron sized delivery systems, which help in transporting drugs, vaccines, antibodies and genes appropriately to the peritoneum for its desired function. This review article delves on how intraperitoneal delivery impacts the therapy of epithelial ovarian cancer spanning the conventional therapeutic modes to the recent nanoinnovations in chemotherapy, immunotherapy and gene therapy.

Biomedical Application of Nanogels: From Cancer to Wound Healing

Nanogels are polymer-based, crosslinked hydrogel particles on the nanometer scale. Nanogels developed from synthetic and natural polymers have gathered a great deal of attention in industry and scientific society due to having an increased surface area, softness, flexibility, absorption, and drug loading ability, as well as their mimicking the environment of a tissue. Nanogels having biocompatibility, nontoxic and biodegradable properties with exceptional design, fabrication, and coating facilities may be used for a variety of different biomedical applications, such as drug delivery and therapy, tissue engineering, and bioimaging. Nanogels fabricated by chemical crosslinking and physical self-assembly displayed the ability to encapsulate therapeutics, including hydrophobic, hydrophilic, and small molecules, proteins, peptides, RNA and DNA sequences, and even ultrasmall nanoparticles within their three-dimensional polymer networks. One of the many drug delivery methods being investigated as a practical option for targeted delivery of drugs for cancer treatment is nanogels. The delivery of DNA and anticancer drugs like doxorubicin, epirubicin, and paclitaxel has been eased by polymeric nanogels. Stimuli-responsive PEGylated nanogels have been reported as smart nanomedicines for cancer diagnostics and therapy. Another promising biomedical application of nanogels is wound healing. Wounds are injuries to living tissue caused by a cut, blow, or other impact. There are numerous nanogels having different polymer compositions that have been reported to enhance the wound healing process, such as hyaluronan, poly-L-lysine, and berberine. When antimicrobial resistance is present, wound healing becomes a complicated process. Researchers are looking for novel alternative approaches, as foreign microorganisms in wounds are becoming resistant to antibiotics. Silver nanogels have been reported as a popular antimicrobial choice, as silver has been used as an antimicrobial throughout a prolonged period. Lignin-incorporated nanogels and lidocaine nanogels have also been reported as an antioxidant wound-dressing material that can aid in wound healing. In this review, we will summarize recent progress in biomedical applications for various nanogels, with a prime focus on cancer and wound healing.

Anionic polysaccharides as delivery carriers for cancer therapy and theranostics: An overview of significance

Recently, cancer therapy has witnessed remarkable advancements with a growing focus on precision medicine and targeted drug delivery strategies. The application of anionic polysaccharides has gained traction in various drug delivery systems. Anionic polysaccharides have emerged as promising delivery carriers in cancer therapy and theranostics, offering numerous advantages such as biocompatibility, low toxicity, and the ability to encapsulate and deliver therapeutic agents to tumor sites with high specificity. This review underscores the significance of anionic polysaccharides as essential components of the evolving landscape of cancer therapy and theranostics. These polymers can be tailored to carry a wide range of therapeutic cargo, including chemotherapeutic agents, nucleic acids, and imaging agents. Their negative charge enables electrostatic interactions with positively charged drugs and facilitates the formation of stable nanoparticles, liposomes, or hydrogels for controlled drug release. Additionally, their hydrophilic nature aids in prolonging circulation time, reducing drug degradation, and minimizing off-target effects. Besides, some of them could act as targeting agents or therapeutic compounds that lead to improved therapeutic performance. This review offers valuable information for researchers, clinicians, and biomedical engineers. It provides insights into the recent progress in the applications of anionic polysaccharide-based delivery platforms in cancer theranostics to transform patient outcomes.

Advancements in Hydrogel-Based Therapies for Ovarian Cancer: A Review

Ovarian cancer, the most deadly gynecologic malignancy, is often resistant to conventional antitumor therapy due to various factors such as severe side effects, unexpected recurrence, and significant tissue damage. The limitations of current treatments and the resistance of invasive tumor cells contribute to these challenges. Hydrogel therapy has recently emerged as a potential treatment option for ovarian cancer, offering advantages such as controllability, biocompatibility, high drug loading capacity, prolonged drug release, and responsiveness to specific stimuli. Hence, the utilization of biodegradable hydrogels as carriers for chemotherapeutic agents has emerged as a significant concern in the field. Injectable hydrogel-based drug delivery systems, in particular, have demonstrated superior efficacy compared to traditional systemic chemotherapy for cancer treatment. The pliability of hydrogel therapy allows for access to anatomical regions that may be challenging for surgical intervention. This review article examines recent advancements in the application of hydrogels for diagnosing and treating ovarian cancer, while also proposing a novel direction for the use of hydrogel technology in this context. The objective of this article is to offer a novel point of reference and serve as a source of inspiration for the advancement of more precise and individualized cancer therapies.

Ovarian cancer and its management through advanced drug delivery system

Ovarian cancer is the deadliest gynecological cancer, often being diagnosed at a late-stage when the disease is already advanced. This makes it known as the ''silent killer'' due to its high mortality rate among women. The ovary itself is composed of three main types of cells epithelial cells, germ cells, and stromal cells. Over 90% of all occurrences of ovarian cancer are epithelial ovarian carcinoma. Ovarian cancer is responsible for 2.5% of cancer in women. The primary signs include stomach bloating, trouble eating or feeling full rapidly, fatigue, and discomfort during intercourse. The management of ovarian cancer is improved by advanced drug delivery systems because they increase therapeutic targeting, reduce side effects, and overcome drug resistance. Accurate distribution to cancer cells is made possible by methods such as ligand-functionalized nanomedicines, dual-targeted nano-drugs, drug conjugates, antibody-drug conjugates and peptide/folate drug conjugates. These technologies enhance individualized and successful ovarian cancer treatment outcomes by maximizing chemotherapy efficacy, extending drug release, and lowering toxicity.

Nanogels-Innovative Drug Carriers for Overcoming Biological Membranes

Nanogels are promising drug delivery systems since they possess undeniable advantages such as high loading capacity for hydrophilic and hydrophobic drugs, stabilization of sensitive drugs, biocompatibility, and biodegradability. The present review summarizes experimental studies related to carriers, drug loading, and membrane transport of nanogels. In particular, the review discusses the properties, advantages, and limitations of polymeric carriers with respect to the behavior of the prepared nanogels in in vivo conditions. The potential of nanogel systems for encapsulation of hydrophilic or hydrophobic drugs and the mechanisms of loading and drug release are also emphasized. Moreover, the challenges related to nanogel transport through the barriers presented in parenteral, oral, ocular, nasal, and dermal routes of administration are also considered.

Peritoneal chemotherapy delivery systems for ovarian cancer treatment: systematic review of animal models

Introduction

Intraperitoneal chemotherapy for ovarian cancer treatment has controversial benefits as most methodologies are associated with significant morbidity. We carried out a systematic review to compare tumor response, measured by tumor weight and volume, between intraperitoneal chemotherapy delivered via drug delivery systems (DDSs) and free intraperitoneal chemotherapy in animal models of ovarian cancer. The secondary aim was to assess the toxicity of DDS-delivered chemotherapy, based on changes in animal body weight.

Methods

Based on PRISMA and SYRCLE guidelines, we identified 38 studies for review, of which 20, were used in the meta-analysis. We evaluated outcome, through tumor volume and tumor weight and, toxicity, through animal weight. Analysis was based on drugs employed and treatment duration.

Results

Most studies were performed on mice. Ovarian cancer cell lines most commonly used to induce xenografts were SKOV3 (19 studies) and A2780 (6 studies). Intraperitoneal device, also known as drug delivery systems (DDS), consisted in nanoparticles, hydrogels, lipid polymer and others. The most commonly used drugs were paclitaxel and cisplatin. Most studies used as the control treatment the same chemotherapy applied free intraperitoneally and tumor response/animal weight were evaluated weekly. There was a small benefit in overall tumor reduction in animals treated with intraperitoneal chemotherapy applied through the slow release device compared with animals treated with intraperitoneal free chemotherapy, as evaluated through tumor weight - results in standardized mean difference. (-1.06; 95% CI: -1.34, -0.78) and tumor volume (-3.72; 95% CI: -4.47, -2.97), a benefit that was seen in most weekly evaluations and for most chemotherapy drugs, such as carboplatin (tumor weight: -5.60; 95% CI: -7.83, -3.37), paclitaxel (tumor weight: -1.18; 95% CI: -1.52, -0.83), and cisplatin (tumor volume: -2.85; 95% CI: -3.66, -2.04) carboplatin (tumor volume: -12.71; 95% CI: -17.35, -8.07); cisplatin (tumor volume: -7.76; 95% CI: -9.88, -5.65); paclitaxel (tumor volume: -2.85; 95% CI: -3.66, -2.04). Regarding animal weight, there was no weight reduction in animals treated with intraperitoneal chemotherapy applied through the slow-release device compared with animals treated with intraperitoneal free chemotherapy. However, significant heterogeneity was observed in some comparisons.

Conclusion

slow-release devices are overall safe and effective in animal models of ovarian cancer. It was not possible to evaluate which one is the most promising device to treat ovarian cancer, because many different types were used to apply chemotherapy intraperitoneally.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42021224573.

The journey of nanoparticles in the abdominal cavity: Exploring their in vivo fate and impact factors

Peritoneal carcinomatosis (PC) is caused by metastasis of primary tumor cells from intra-abdominal organs to the peritoneal surface. Intraperitoneal (IP) chemotherapy allows close contact of high concentrations of therapeutic agents with cancer cells in the peritoneal cavity to prolong patient survival. However, conventional IP chemotherapy is prone to rapid elimination from the peritoneal cavity and lacks specificity towards cancer cells. To address these challenges, there is an imperative demand for exploiting novel drug delivery systems to enhance drug retention in the peritoneal cavity and target PC cells. Therefore, in this review, we first recapitulate the physiological structures and barriers associated with IP drug delivery, highlighting the in vivo fate of nanoparticles (NPs) after IP administration. Furthermore, the influence of physicochemical properties (particle size, charge, surface modification, and carrier composition) on the in vivo fate of NPs is discussed. Perspectives on the rational design of NPs for IP therapy and recent clinical progress are also provided.

Remodeling the tumor immune microenvironment through hydrogel encapsulated G-Rh2 in situ vaccine and systemic immunotherapy

Ginsenoside Rh2 (G-Rh2) is a vital bioactive compound in Traditional Chinese Medicine, celebrated for its strong pharmacological properties, particularly its potent antitumor effects. However, its poor water solubility and limited bioavailability have necessitated the development of a novel drug delivery method. In this study, we utilized an indocyanine green carboxylic acid-hydroxypropyl cellulose-abietic acid-bovine serum albumin hydrogel (ICG-HPC-AA/BSA hydrogel) as a tumor in situ vaccine to enhance the permeability, retention, and tumor-targeted therapeutic efficacy of G-Rh2. We examined the therapeutic impact of a G-Rh2-loaded hydrogel combined with systemic PD-1 antibody treatment in murine models of H22 liver cancer and CT26 colon cancer. Additionally, we explored the immune microenvironment of the tumors influenced by this in situ vaccination strategy.

Construction and performance evaluation of polyguluronic acid polysaccharides-based drug delivery systems

Polysaccharides have garnered significant attention as potential nanoparticle carriers for targeted tumor therapy due to their excellent biodegradability and biocompatibility. Polyguluronic acid (PG) is a homogeneous acidic polysaccharide fragment derived from alginate, which is found in brown algae, possesses excellent bioactivities, unique properties. This study explored the immunomodulatory activity of PG and developed PG-based nanogels through modified disulfide bonds and Ca2+ dual crosslinking. We characterized their structure, assessed their drug-loading and release properties, and ultimately validated both the safety of the nanocarrier and the in vitro anti-tumor efficacy of the encapsulated drug. Results indicated that PG significantly enhanced the proliferative activity and phagocytosis of RAW264.7 cells while promoting reactive oxygen species (ROS) production and cytokine secretion. The study identified TLR4 as the primary receptor for PG recognition in RAW264.7 cells. Furthermore, PG-based drug-carrying nanogels were prepared, exhibiting uniform sizes of about 184 nm and demonstrating exceptional encapsulation efficiency (82.15 ± 0.82 %) and drug loading capacity (8.12 ± 0.08 %). In vitro release experiments showed that these nanogels could responsively release drugs under conditions of high glutathione (GSH) reduction, facilitating drug accumulation at tumor sites and enhancing therapeutic efficacy. This research not only expands the application of PG in drug delivery systems but also provides valuable insights into leveraging natural immunomodulatory polysaccharides as carriers for targeted drug delivery.

Intraperitoneal drug delivery systems for peritoneal carcinomatosis: Bridging the gap between research and clinical implementation

Several abdominal-located cancers develop metastasis within the peritoneum, what is called peritoneal carcinomatosis (PC), constituting a clinical challenge in their therapeutical management, often leading to poor prognoses. Current multidisciplinary strategies, including cytoreductive surgery (CRS), hyperthermic intraperitoneal chemotherapy (HIPEC), and pressurized intraperitoneal aerosol chemotherapy (PIPAC), demonstrate efficacy but have limitations. In response, alternative strategies are explored in the drug delivery field for intraperitoneal chemotherapy. Controlled drug delivery offers a promising avenue, maintaining localized drug concentrations for optimal PC management. Drug delivery systems (DDS), including hydrogels, implants, nanoparticles, and hybrid systems, show potential for sustained and region-specific drug release. The present review aims to offer an overview of the advances and current designs of DDS for PC chemotherapy administration, focusing on their composition, main characteristics, and principal experimental outcomes, highlighting the importance of biomaterial rationale design and in vitro/vivo models for their testing. Moreover, since clinical data for human subjects are scarce, we offer a critical discussion of the gap between bench and bedside in DDS translation, emphasizing the need for further research.

Hybrid Nanoparticle-Hydrogel Systems for Drug Delivery Depots and Other Biomedical Applications

Hydrogel-based depots typically tend to remain where injected and have excellent biocompatibility but are relatively poor at controlling drug release. Nanoparticles (NPs) typically have the opposite properties. The smaller the NPs are, the more likely they are to leave the site of injection. Their biocompatibility is variable depending on the material but can be poor. However, NPs can be good at controlling drug release. In these and other properties, combining NPs and hydrogels can leverage their advantages and negate their disadvantages. This review highlights the rationale for hybrid NP-hydrogel systems in drug delivery, the basic methods of producing them, and examples where combining the two systems addressed specific problems.

3D bioprinting cowpea mosaic virus as an immunotherapy depot for ovarian cancer prevention in a preclinical mouse model

Implantable polymeric hydrogels loaded with immunostimulatory cowpea mosaic virus (CPMV) were fabricated using digital light processing (DLP) printing technology. The CPMV-laden hydrogels were surgically implanted into the peritoneal cavity to serve as depots for cancer slow-release immunotherapy. Sustained release of CPMV within the intraperitoneal space alleviates the need for repeated dosing and we demonstrated efficacy against ovarian cancer in a metastatic mouse model.

Fabrication of Drug-Loaded Torus-Shaped Alginate Microparticles and Kinetic Analysis of Their Drug Release

We fabricated drug-loaded, microsized, and torus-shaped alginate microparticles (TSMs) by vortex-ring freezing (VRF), utilizing vortex ring formation and ionic cross-linking. The equivalent outer diameter of the TSMs was ca. 200 μm. Several model drugs, such as doxorubicin, heparin, lysozyme, and several dextran derivatives, have been successfully loaded into TSMs. Because the TSMs were fragile due to the limitation of the process conditions of the VRF, drug-loaded TSMs were subsequently cross-linked via "post-cross-linking" with CaCl2, SrCl2, or BaCl2 to increase the cross-linking density of the alginate matrix, thereby enhancing the stability of dextran (Dex)-loaded TSMs (Dex-TSMs) and enabling the sustained release of natural Dex of 10, 70, or 150 kDa and cationic or anionic Dex at a physiological pH. The release kinetics of Dexs showed molecular weight and charge dependence; a relatively dense network of the alginate matrix of post-cross-linked TSMs resulted in the sustained release of Dexs with high molecular weights, heparin, and lysozyme for up to 7 days in the release test. Furthermore, the solute diffusivities of the dextran derivatives in the bulk alginate matrix were measured by using fluorescence correlation spectroscopy, which supported the release kinetics of TSMs. Drug-loaded TSMs have potential as drug carriers for biopharmaceuticals, such as proteins.

Development of a Supramolecular Hydrogel for Intraperitoneal Injections

Local intraperitoneal drug administration is considered a challenging drug delivery route. The therapeutic efficiency is low, mainly due to rapid clearance of drugs. To increase the intraperitoneal retention time of specific drugs, a pH-sensitive supramolecular hydrogel that can act as a drug delivery vehicle is developed. To establish the optimal formulation of the hydrogel and to study its feasibility, safety, and tissue compatibility, in vitro, postmortem, and in vivo experiments are performed. In vitro tests reveal that a hydrogelator formulation with pH ≥ 9 results in a constant viscosity of 0.1 Pa·s. After administration postmortem, the hydrogel covers the parietal and visceral peritoneum with a thin, soft layer. In the subsequent in vivo experiments, 14 healthy rats are subjected to intraperitoneal injection with the hydrogel. Fourteen and 28 days after implantation, the animals are euthanized. Intraperitoneal exposure to the hydrogel is not resulted in significant weight loss or discomfort. Moreover, no macroscopic adverse effects or signs of organ damage are detected. In several intra-abdominal tissues, vacuolated macrophages are found indicating a physiological degradation of the synthetic hydrogel. This study demonstrates that the supramolecular hydrogel is safe for intraperitoneal application and that the hydrogel shows good tissue compatibility in rats.

An updated landscape on nanotechnology-based drug delivery, immunotherapy, vaccinations, imaging, and biomarker detections for cancers: recent trends and future directions with clinical success

The recent development of nanotechnology-based formulations improved the diagnostics and therapies for various diseases including cancer where lack of specificity, high cytotoxicity with various side effects, poor biocompatibility, and increasing cases of multi-drug resistance are the major limitations of existing chemotherapy. Nanoparticle-based drug delivery enhances the stability and bioavailability of many drugs, thereby increasing tissue penetration and targeted delivery with improved efficacy against the tumour cells. Easy surface functionalization and encapsulation properties allow various antigens and tumour cell lysates to be delivered in the form of nanovaccines with improved immune response. The nanoparticles (NPs) due to their smaller size and associated optical, physical, and mechanical properties have evolved as biosensors with high sensitivity and specificity for the detection of various markers including nucleic acids, protein/antigens, small metabolites, etc. This review gives, initially, a concise update on drug delivery using different nanoscale platforms like liposomes, dendrimers, polymeric & various metallic NPs, hydrogels, microneedles, nanofibres, nanoemulsions, etc. Drug delivery with recent technologies like quantum dots (QDs), carbon nanotubes (CNTs), protein, and upconverting NPs was updated, thereafter. We also summarized the recent progress in vaccination strategy, immunotherapy involving immune checkpoint inhibitors, and biomarker detection for various cancers based on nanoplatforms. At last, we gave a detailed picture of the current nanomedicines in clinical trials and their possible success along with the existing approved ones. In short, this review provides an updated complete landscape of applications of wide NP-based drug delivery, vaccinations, immunotherapy, biomarker detection & imaging for various cancers with a predicted future of nanomedicines that are in clinical trials.

Platinum-based drugs and hydrogel: a promising anti-tumor combination

Platinum-based drugs are widely used as first-line anti-tumor chemotherapy agents. However, they also have nonnegligible side effects due to the free drugs in circulation. Therefore, it is necessary to develop efficient and safe delivery systems for better tumor cell targeting. Hydrogel is a promising anti-tumor drug carrier that can form a platinum/hydrogel combination system for drug release, which has shown better anti-tumor effects in some studies. However, there is a lack of systematic summary in this field. This review aims to provide a comprehensive overview of the platinum/hydrogel combination system with the following sections: firstly, an introduction of platinum-based drugs; secondly, an analysis of the platinum/hydrogel combination system; and thirdly, a discussion of the advantages of the hydrogel-based delivery system. We hope this review can offer some insights for the development of the platinum/hydrogel combination system for better cancer therapy.

Localized chemotherapy approaches and advanced drug delivery strategies: a step forward in the treatment of peritoneal carcinomatosis from ovarian cancer

Peritoneal carcinomatosis (PC) is a common outcome of epithelial ovarian carcinoma and is the leading cause of death for these patients. Tumor location, extent, peculiarities of the microenvironment, and the development of drug resistance are the main challenges that need to be addressed to improve therapeutic outcome. The development of new procedures such as HIPEC (Hyperthermic Intraperitoneal Chemotherapy) and PIPAC (Pressurized Intraperitoneal Aerosol Chemotherapy) have enabled locoregional delivery of chemotherapeutics, while the increasingly efficient design and development of advanced drug delivery micro and nanosystems are helping to promote tumor targeting and penetration and to reduce the side effects associated with systemic chemotherapy administration. The possibility of combining drug-loaded carriers with delivery via HIPEC and PIPAC represents a powerful tool to improve treatment efficacy, and this possibility has recently begun to be explored. This review will discuss the latest advances in the treatment of PC derived from ovarian cancer, with a focus on the potential of PIPAC and nanoparticles in terms of their application to develop new therapeutic strategies and future prospects.

Nanotechnology-integrated ovarian cancer metastasis therapy: Insights from the metastatic mechanisms into administration routes and therapy strategies

Ovarian cancer is a kind of malignant tumour which locates in the pelvic cavity without typical clinical symptoms in the early stages. Most patients are diagnosed in the late stage while about 60 % of them have suffered from the cancer cells spreading in the abdominal cavity. The high recurrence rate and mortality seriously damage the reproductive needs and health of women. Although recent advances in therapeutic regimes and other adjuvant therapies improved the overall survival of ovarian cancer, overcoming metastasis has still been a challenge and is necessary for achieving cure of ovarian cancer. To present potential targets and new strategies for curbing the occurrence of ovarian metastasis and the treatment of ovarian cancer after metastasis, the first section of this paper explained the metastatic mechanisms of ovarian cancer comprehensively. Nanomedicine, not limited to drug delivery, offers opportunities for metastatic ovarian cancer therapy. The second section of this paper emphasized the advantages of various administration routes of nanodrugs in metastatic ovarian cancer therapy. Furthermore, the third section of this paper focused on advances in nanotechnology-integrated strategies for targeting metastatic ovarian cancer based on the metastatic mechanisms of ovarian cancer. Finally, the challenges and prospects of nanotherapeutics for ovarian cancer metastasis therapy were evaluated. In general, the greatest emphasis on using nanotechnology-based strategies provides avenues for improving metastatic ovarian cancer outcomes in the future.

Alginate-Based Hydrogels and Scaffolds for Biomedical Applications

Alginate is a natural polymer of marine origin and, due to its exceptional properties, has great importance as an essential component for the preparation of hydrogels and scaffolds for biomedical applications. The design of biologically interactive hydrogels and scaffolds with advanced, expected and required properties are one of the key issues for successful outcomes in the healing of injured tissues. This review paper presents the multifunctional biomedical applications of alginate-based hydrogels and scaffolds in selected areas, highlighting the key effect of alginate and its influence on the essential properties of the selected biomedical applications. The first part covers scientific achievements for alginate in dermal tissue regeneration, drug delivery systems, cancer treatment, and antimicrobials. The second part is dedicated to our scientific results obtained for the research opus of hydrogel materials for scaffolds based on alginate in synergy with different materials (polymers and bioactive agents). Alginate has proved to be an exceptional polymer for combining with other naturally occurring and synthetic polymers, as well as loading bioactive therapeutic agents to achieve dermal, controlled drug delivery, cancer treatment, and antimicrobial purposes. Our research was based on combinations of alginate with gelatin, 2-hydroxyethyl methacrylate, apatite, graphene oxide and iron(III) oxide, as well as curcumin and resveratrol as bioactive agents. Important features of the prepared scaffolds, such as morphology, porosity, absorption capacity, hydrophilicity, mechanical properties, in vitro degradation, and in vitro and in vivo biocompatibility, have shown favorable properties for the aforementioned applications, and alginate has been an important link in achieving these properties. Alginate, as a component of these systems, proved to be an indispensable factor and played an excellent “role” in the optimal adjustment of the tested properties. This study provides valuable data and information for researchers and demonstrates the importance of the role of alginate as a biomaterial in the design of hydrogels and scaffolds that are powerful medical “tools” for biomedical applications.

Advances in Algin and Alginate-Hybrid Materials for Drug Delivery and Tissue Engineering

In this review, we aim to provide a summary of recent research advancements and applications of algin (i.e., alginic acid) and alginate-hybrid materials (AHMs) in medical fields. Algin/alginate are abundant natural products that are chemically inert and biocompatible, and they have superior gelation properties, good mechanical strengths, and biodegradability. The AHMs have been widely applied in wound dressing, cell culture, tissue engineering, and drug delivery. However, medical applications in different fields require different properties in the AHMs. The drug delivery application requires AHMs to provide optimal drug loading, controlled and targeted drug-releasing, and/or visually guided drug delivery. AHMs for wound dressing application need to have improved mechanical properties, hydrophilicity, cell adhesion, and antibacterial properties. AHMs for tissue engineering need improved mechanical properties that match the target organs, superior cell affinity, and cell loading capacity. Various methods to produce AHMs that meet different needs were summarized. Formulations to form AHMs with improved stability, drug/cell-loading capacity, cell adhesion, and mechanical properties are active research areas. This review serves as a road map to provide insights into the strategies to develop AHMs in medical applications.

A Simple Preparation Method of Gelatin Hydrogels Incorporating Cisplatin for Sustained Release

The objective of this study was to develop a new preparation method for cisplatin (CDDP)-incorporated gelatin hydrogels without using chemical crosslinking nor a vacuum heating instrument for dehydrothermal crosslinking. By simply mixing CDDP and gelatin, CDDP-crosslinked gelatin hydrogels (CCGH) were prepared. CDDP functions as a crosslinking agent of gelatin to form the gelatin hydrogel. Simultaneously, CDDP is incorporated into the gelatin hydrogel as a controlled release carrier. CDDP's in vitro and in vivo anticancer efficacy after incorporation into CCGH was evaluated. In the in vitro system, the CDDP was released gradually due to CCGH degradation with an initial burst release of approximately 16%. CDDP metal-coordinated with the degraded fragment of gelatin was released from CCGH with maintaining the anticancer activity. After intraperitoneal administration of CCGH, CDDP was detected in the blood circulation while its toxicity was low. Following intraperitoneal administration of CCGH in a murine peritoneal dissemination model of human gastric cancer MKN45-Luc cell line, the survival time was significantly prolonged compared with free CDDP solution. It is concluded that CCGH prepared by the CDDP-based crosslinking of gelatin is an excellent sustained release system of CDDP to achieve superior anticancer effects with minimal side effects compared with free CDDP solution.

Nanogels as target drug delivery systems in cancer therapy: A review of the last decade

Cancer is an important cause of morbidity and mortality worldwide, irrespective of the level of human development. Globally, it was estimated that there were 19.3 million new cases of cancer and almost 10 million deaths from cancer in 2020. The importance of prevention, early detection as well as effective cancer therapies cannot be over-emphasized. One of the important strategies in cancer therapy is targeted drug delivery to the specific tumor sites. Nanogels are among the several drug delivery systems (DDS) being explored as potential candidates for targeted drug delivery in cancer therapy. Nanogels, which are new generation, versatile DDS with the possession of dual characteristics of hydrogels and nanoparticles have shown great potential as targeted DDS in cancer therapy. Nanogels are hydrogels with a three-dimensional (3D) tunable porous structure and a particle size in the nanometre range, from 20 to 200 nm. They have been visualized as ideal DDS with enormous drug loading capacity, and high stability. Nanogels can be modified to achieve active targeting and enhance drug accumulation in disease sites. They can be designed to be stimulus-responsive, and react to internal or external stimuli such as pH, temperature, light, redox, thus resulting in the controlled release of loaded drug. This prevents drug accumulation in non-target tissues and minimizes the side effects of the drug. Drugs with severe adverse effects, short circulation half-life, and easy degradability by enzymes, such as anti-cancer drugs, and proteins, are suitable for delivery by chemically cross-linked or physically assembled nanogel systems. This systematic review summarizes the evolution of nanogels for targeted drug delivery for cancer therapy over the last decade. On-going clinical trials and recent applications of nanogels as targeted DDS for cancer therapy will be discussed in detail. The review will be concluded with discussions on safety and regulatory considerations as well as future research prospects of nanogel-targeted drug delivery for cancer therapy.