Immunotherapies for locally aggressive cancers

Improving surgical resection outcomes for locally aggressive tumors is key to inducing durable locoregional disease control and preventing progression to metastatic disease. Macroscopically complete resection of the tumor is the standard of care for many cancers, including breast, ovarian, lung, sarcoma, and mesothelioma. Advancements in cancer diagnostics are increasing the number of surgically eligible cases through early detection. Thus, a unique opportunity arises to improve patient outcomes with decreased recurrence rates via intraoperative delivery treatments using local drug delivery strategies after the tumor has been resected. Of the current systemic treatments (e.g., chemotherapy, targeted therapies, and immunotherapies), immunotherapies are the latest approach to offer significant benefits. Intraoperative strategies benefit from direct access to the tumor microenvironment which improves drug uptake to the tumor and simultaneously minimizes the risk of drug entering healthy tissues thereby resulting in fewer or less toxic adverse events. We review the current state of immunotherapy development and discuss the opportunities that intraoperative treatment provides. We conclude by summarizing progress in current research, identifying areas for exploration, and discussing future prospects in sustained remission.

Therapeutic potential of Phycocyanin in gastrointestinal cancers and related disorders

Gastrointestinal cancer is the most fatal cancer worldwide. The etiology of gastrointestinal cancer has yet to be fully characterized. Alcohol consumption, obesity, tobacco, Helicobacter pylori and gastrointestinal disorders, including gastroesophageal reflux disease, gastric ulcer, colon polyps and non-alcoholic fatty liver disease are among the several risks factors for gastrointestinal cancers. Phycocyanin which is abundant in Spirulina. Phycocyanin, a member of phycobiliprotein family with intense blue color, is an anti-diabetic, neuroprotective, anti-oxidative, anti-inflammatory, and anticancer compound. Evidence exists supporting that phycocyanin has antitumor effects, exerting its pharmacological effects by targeting a variety of cellular and molecular processes, i.e., apoptosis, cell-cycle arrest, migration and Wnt/β-catenin signaling. Phycocyanin has also been applied in treatment of several gastrointestinal disorders such as, gastric ulcer, ulcerative colitis and fatty liver that is known as a risk factor for progression to cancer. Herein, we summarize various cellular and molecular pathways that are affected by phycocyanin, its efficacy upon combined drug treatment, and the potential for nanotechnology in its gastrointestinal cancer therapy.

Dendronized Ag/Au Nanomats: Antimicrobial Scaffold for Wound Healing Bandages

Electrospun polymer nanofibers, due to high surface area-to-volume ratio, high porosity, good mechanical strength, and ease of functionalization, appear as promising multifunctional materials for biomedical applications. Thanks to their unidirectional structure, imitating the extracellular matrix (ECM), they can be used as scaffolds for cell adhesion and proliferation. In addition, the incorporation of active groups inside nanofiber can give properties for bactericides. The proposed nanomats incorporate nanoparticles templated within the electrospun nanofibers that prevent infections and stimulate tissue regeneration. The generated hybrid electrospun nanofibers are composed of a copolymer of L-lactide-block-ε-caprolactone (PL-b-CL), 70:30, blended with homopolymer polyvinylpyrrolidone (PVP) and gold (Au) nanoparticles. A low cytotoxicity and slightly increased immunoreactivity, stimulated by the nanomat, are observed. Moreover, the decoration of the hybrid nanomat with dendronized silver nanoparticles (Dend-Ag) improves their antibacterial activity against antibiotic-resistant Pseudomonas aeruginosa. The use of Dend-Ag for decorating offers several functional effects; namely, it enhances the antibacterial properties of the produced nanomats and induces a significant increase within macrophages' cytotoxicity. The unidirectional nanostructures of the generated hybrid nanomats demonstrate unique collective physio-chemical and biological properties suitable for a wide range of biomedical applications. Here, the antibacterial properties facilitate an optimal environment, contributing to accelerated wound healing.

Boosting antitumor efficacy using docetaxel-loaded nanoplatforms: from cancer therapy to regenerative medicine approaches

The intersection of nanotechnology and pharmacology has revolutionized the delivery and efficacy of chemotherapeutic agents, notably docetaxel, a key drug in cancer treatment. Traditionally limited by poor solubility and significant side effects, docetaxel's therapeutic potential has been significantly enhanced through its incorporation into nanoplatforms, such as nanofibers and nanoparticles. This advancement offers targeted delivery, controlled release, and improved bioavailability, dramatically reducing systemic toxicity and enhancing patient outcomes. Nanofibers provide a versatile scaffold for the controlled release of docetaxel, utilizing techniques like electrospinning to tailor drug release profiles. Nanoparticles, on the other hand, enable precise drug delivery to tumor cells, minimizing damage to healthy tissues through sophisticated encapsulation methods such as nanoprecipitation and emulsion. These nanotechnologies not only improve the pharmacokinetic properties of docetaxel but also open new avenues in regenerative medicine by facilitating targeted therapy and cellular regeneration. This narrative review highlights the transformative impact of docetaxel-loaded nanoplatforms in oncology and beyond, showcasing the potential of nanotechnology to overcome the limitations of traditional chemotherapy and pave the way for future innovations in drug delivery and regenerative therapies. Through these advancements, nanotechnology promises a new era of precision medicine, enhancing the efficacy of cancer treatments while minimizing adverse effects.

Novel Drug Delivery Approaches for the Localized Treatment of Cervical Cancer

Cervical cancer (CC) is the fourth leading cancer type in females globally. Being an ailment of the birth canal, primitive treatment strategies, including surgery, radiation, or laser therapy, bring along the risk of infertility, neonate mortality, premature parturition, etc. Systemic chemotherapy led to systemic toxicity. Therefore, delivering a smaller cargo of therapeutics to the local site is more beneficial in terms of efficacy as well as safety. Due to the regeneration of cervicovaginal mucus, conventional dosage forms come with the limitations of leaking, the requirement of repeated administration, and compromised vaginal retention. Therefore, these days novel strategies are being investigated with the ability to combat the limitations of conventional formulations. Novel carriers can be engineered to manipulate bioadhesive properties and sustained release patterns can be obtained thus leading to the maintenance of actives at therapeutic level locally for a longer period. Other than the purpose of CC treatment, these delivery systems also have been designed as postoperative care where a certain dose of antitumor agent will be maintained in the cervix postsurgical removal of the tumor. Herein, the most explored localized delivery systems for the treatment of CC, namely, nanofibers, nanoparticles, in situ gel, liposome, and hydrogel, have been discussed in detail. These carriers have exceptional properties that have been further modified with the aid of a wide range of polymers in order to serve the required purpose of therapeutic effect, safety, and stability. Further, the safety of these delivery systems toward vital organs has also been discussed.

Tissue Engineering Scaffolds Loaded With a Variety of Plant Extracts: Novel Model in Breast Cancer Therapy

Despite recent improvements in detecting and managing breast cancer (BC), it continues to be a major worldwide health concern that annually affects millions of people. Exploring the anti-BC potentials of natural compounds has received a lot of scientific attention due to their multi-target mode of action and good safety profiles because of these unmet needs. Drugs made from herbs are secure and have a lot fewer negative effects than those made from synthetic materials. Early stage patients benefit from breast-conserving surgery, but the risk of local recurrence remains, necessitating implanted scaffolds. These scaffolds provide residual cancer cell killing and tailored drug delivery. This review looks at plant extract-infused tissue engineering scaffolds, which provide a novel approach to treating BC. By offering patient individualized, safer treatments, these scaffolds could completely change how BC is treated.

Integration of polysaccharide electrospun nanofibers with microneedle arrays promotes wound regeneration: A review

Utilizing electrospun nanofibers and microneedle arrays in wound regeneration has been practiced for several years. Researchers have recently asserted that using multiple methods concurrently might enhance efficiency, despite the inherent strengths and weaknesses of each individual approach. The combination of microneedle arrays with electrospun nanofibers has the potential to create a drug delivery system and wound healing method that offer improved efficiency and accuracy in targeting. The use of microneedles with nanofibers allows for precise administration of pharmaceuticals due to the microneedles' capacity to pierce the skin and the nanofibers' role as a drug reservoir, resulting in a progressive release of drugs over a certain period of time. Electrospun nanofibers have the ability to imitate the extracellular matrix and provide a framework for cellular growth and tissue rejuvenation, while microneedle arrays show potential for enhancing tissue regeneration and enhancing the efficacy of wound healing. The integration of electrospun nanofibers with microneedle arrays may be customized to effectively tackle particular obstacles in the fields of wound healing and drug delivery. However, some issues must be addressed before this paradigm may be fully integrated into clinical settings, including but not limited to ensuring the safety and sterilization of these products for transdermal use, optimizing manufacturing methods and characterization of developed products, larger-scale production, optimizing storage conditions, and evaluating the inclusion of multiple therapeutic and antimicrobial agents to increase the synergistic effects in the wound healing process. This research examines the combination of microneedle arrays with electrospun nanofibers to enhance the delivery of drugs and promote wound healing. It explores various kinds of microneedle arrays, the materials and processes used, and current developments in their integration with electrospun nanofibers.

Exploring the vast potentials and probable limitations of novel and nanostructured implantable drug delivery systems for cancer treatment

Conventional cancer chemotherapy regimens, albeit successful to some extent, suffer from some significant drawbacks, such as high-dose requirements, limited bioavailability, low therapeutic indices, emergence of multiple drug resistance, off-target distribution, and adverse effects. The main goal of developing implantable drug delivery systems (IDDS) is to address these challenges and maintain anti-cancer drugs directly at the intended sites of therapeutic action while minimizing inevitable side effects. IDDS possess numerous advantages over conventional drug delivery, including controlled drug release patterns, one-time drug administration, as well as loading and stabilizing poorly water-soluble chemotherapy drugs. Here, we summarized conventional and novel (three-dimensional (3D) printing and microfluidic) preparation techniques of different IDDS, including nanofibers, films, hydrogels, wafers, sponges, and osmotic pumps. These systems could be designed with high biocompatibility and biodegradability features using a wide variety of natural and synthetic polymers. We also reviewed the published data on these systems in cancer therapy with a particular focus on their release behavior. Various release profiles could be attained in IDDS, which enable predictable, adjustable, and sustained drug releases. Furthermore, multi-step or stimuli-responsive drug release could be obtained in these systems. The studies mentioned in this article have proven the effectiveness of IDDS for treating different cancer types with high prevalence, including breast cancer, and aggressive cancer types, such as glioblastoma and liver cancer. Additionally, the challenges in applying IDDS for efficacious cancer therapy and their potential future developments are also discussed. Considering the high potential of IDDS for further advancements, such as programmable release and degradation features, further clinical trials are needed to ensure their efficiency. The overall goal of this review is to expand our understanding of the behavior of commonly investigated IDDS and to identify the barriers that should be addressed in the pursuit of more efficient therapies for cancer. See also the graphical abstract(Fig. 1).

Incorporation of doxorubicin and CoFe2O4 nanoparticles into the cellulose acetate phthalate / polyvinyl alcohol (core)/ polyurethane (shell) nanofibers against A549 human lung cancer during chemotherapy/hyperthermia combined method

Cellulose acetate phthalate (CAP)/polyvinyl alcohol (PVA)/polyurethane (PU) nanofibers were synthesized by simple and coaxial electrospinning (ES) processes. Doxorubicin (DOX) and the CoFe2O4 nanoparticles were loaded into the nanofibers. The performance of the prepared nanofibers was investigated for the sustained release of DOX against A541 lung cancer cells under chemotherapy/external magnetic field (EMF) and alternating magnetic field (AMF, hyperthermia treatment) combined methods in both the in vitro and in vivo conditions. The sustained release of DOX from core-shell nanofibers containing 5 wt% cobalt ferrite was obtained within 300, 600 h, at pH of 5.5 and 7.4 without AMF and 168, 360 h, under an alternating magnetic field (AMF). More than 98.3 ± 0.2 % of A549 cancer cells were killed in the presence of core-shell nanofibers containing 100 μg DOX and 5 % cobalt ferrite nanoparticles in the presence of AMF. The flowcytometric results indicated that only 19.1 and 8.85 % cancer cells remained alive under EMF and AMF, respectively. The in vivo results revealed in stopping the growth of tumor volume and decrease in the relative tumor volume up to 0.5 were obtained using magnetic core-shell nanofibers containing 100 μg DOX and 5 % cobalt ferrite nanoparticles in the presence of EMF and AMF, respectively.

Epidural Administration of Curcumin-Loaded Polycaprolactone/Gelatin Electrospun Nanofibers for Extended Analgesia After Laminectomy in Rats

Several clinical studies have reported the analgesic effect of curcumin (Curc) in various situations such as rheumatoid arthritis, osteoarthritis, and postsurgical pain. Therefore, in this work, Curc-loaded electrospun nanofibers (NFs) are designed to evaluate their sustained release on analgesic effect duration in rats after epidural placement via repeated formalin and tail-flick tests. The Curc-loaded polycaprolactone/gelatin NFs (Curc-PCL/GEL NFs) are prepared through an electrospinning technique and introduced to the rat's epidural space after laminectomy. The physicochemical and morphology features of the prepared Curc-PCL/GEL NFs were characterized via FE-SEM, FTIR, and degradation assay. The in vitro and in vivo concentrations of Curc were measured to evaluate the analgesic efficacy of the drug-loaded NFs. Rat nociceptive responses are investigated through repeated formalin and tail-flick tests for 5 weeks after the placement of NFs. Curc had a sustained release from the NFs for 5 weeks, and its local pharmaceutical concentrations were much greater than plasma concentrations. Rat's pain scores in both early and late phases of the formalin test were remarkably decreased in the experimental period. Rat's tail-flick latency was remarkably enhanced and remained constant for up to 4 weeks. Our findings show that the Curc-PCL/GEL NFs can supply controlled release of Curc to induce extended analgesia after laminectomy.

Implantable smart hyperthermia nanofibers for cancer therapy: Challenges and opportunities

Nanofibers (NFs) with practical drug-loading capacities, high stability, and controllable release have caught the attention of investigators due to their potential applications in on-demand drug delivery devices. Developing novel and efficient multidisciplinary management of locoregional cancer treatment through the design of smart NF-based systems integrated with combined chemotherapy and hyperthermia could provide stronger therapeutic advantages. On the other hand, implanting directly at the tumor area is a remarkable benefit of hyperthermia NF-based drug delivery approaches. Hence, implantable smart hyperthermia NFs might be very hopeful for tumor treatment in the future and provide new avenues for developing highly efficient localized drug delivery systems. Indeed, features of the smart NFs lead to the construction of a reversibly flexible nanostructure that enables hyperthermia and facile switchable release of antitumor agents to eradicate cancer cells. Accordingly, this study covers recent updates on applications of implantable smart hyperthermia NFs regarding their current scope and future outlook. This article is categorized under: Implantable Materials and Surgical Technologies > Nanomaterials and Implants.

Nanoparticles in Medicine: Current Status in Cancer Treatment

Cancer is still a leading cause of deaths worldwide, especially due to those cases diagnosed at late stages with metastases that are still considered untreatable and are managed in such a way that a lengthy chronic state is achieved. Nanotechnology has been acknowledged as one possible solution to improve existing cancer treatments, but also as an innovative approach to developing new therapeutic solutions that will lower systemic toxicity and increase targeted action on tumors and metastatic tumor cells. In particular, the nanoparticles studied in the context of cancer treatment include organic and inorganic particles whose role may often be expanded into diagnostic applications. Some of the best studied nanoparticles include metallic gold and silver nanoparticles, quantum dots, polymeric nanoparticles, carbon nanotubes and graphene, with diverse mechanisms of action such as, for example, the increased induction of reactive oxygen species, increased cellular uptake and functionalization properties for improved targeted delivery. Recently, novel nanoparticles for improved cancer cell targeting also include nanobubbles, which have already demonstrated increased localization of anticancer molecules in tumor tissues. In this review, we will accordingly present and discuss state-of-the-art nanoparticles and nano-formulations for cancer treatment and limitations for their application in a clinical setting.

Curcumin-loaded mesoporous silica nanoparticles for drug delivery: synthesis, biological assays and therapeutic potential - a review

Curcumin-loaded mesoporous silica nanoparticles (MSNs) have shown promise as drug delivery systems to address the limited pharmacokinetic characteristics of curcumin. Functionalization with folic acid and PEGylation enhance anticancer activity, biocompatibility, stability, and permeability. Co-delivery with other drugs results in synergistically enhanced cytotoxic activity. Environment-responsive MSNs prevent undesirable drug leakage and increase selectivity towards target tissues. This review summarizes the methods of Cur-loaded MSN synthesis and functionalization and their application in various diseases, and also highlights the potential of Cur-loaded MSNs as a promising drug delivery system.

Electrospun Drug-Loaded and Gene-Loaded Nanofibres: The Holy Grail of Glioblastoma Therapy?

To date, GBM remains highly resistant to therapies that have shown promising effects in other cancers. Therefore, the goal is to take down the shield that these tumours are using to protect themselves and proliferate unchecked, regardless of the advent of diverse therapies. To overcome the limitations of conventional therapy, the use of electrospun nanofibres encapsulated with either a drug or gene has been extensively researched. The aim of this intelligent biomaterial is to achieve a timely release of encapsulated therapy to exert the maximal therapeutic effect simultaneously eliminating dose-limiting toxicities and activating the innate immune response to prevent tumour recurrence. This review article is focused on the developing field of electrospinning and aims to describe the different types of electrospinning techniques in biomedical applications. Each technique describes how not all drugs or genes can be electrospun with any method; their physico-chemical properties, site of action, polymer characteristics and the desired drug or gene release rate determine the strategy used. Finally, we discuss the challenges and future perspectives associated with GBM therapy.

Novel long-acting brimonidine tartrate loaded-PCL/PVP nanofibers for versatile biomedical applications: fabrication, characterization and antimicrobial evaluation

The global state of antibiotic resistance highlights the necessity for new drugs that can treat a wide range of microbial infections. Drug repurposing has several advantages, including lower costs and improved safety compared to developing a new compound. The aim of the current study is to evaluate the repurposed antimicrobial activity of Brimonidine tartrate (BT), a well-known antiglaucoma drug, and to potentiate its antimicrobial effect by using electrospun nanofibrous scaffolds. BT-loaded nanofibers were fabricated in different drug concentrations (1.5, 3, 6, and 9%) via the electrospinning technique using two biopolymers (PCL and PVP). Then, the prepared nanofibers were characterized by SEM, XRD, FTIR, swelling ratio, and in vitro drug release. Afterward, the antimicrobial activities of the prepared nanofibers were investigated in vitro using different methods against several human pathogens and compared to the free BT. The results showed that all nanofibers were prepared successfully with a smooth surface. The diameters of nanofibers were reduced after loading of BT compared to the unloaded ones. In addition, scaffolds showed controlled-drug release profiles that were maintained for more than 7 days. The in vitro antimicrobial assessments revealed good activities for all scaffolds against most of the investigated human pathogens, particularly the one prepared with 9% BT which showed superiority in the antimicrobial effect over other scaffolds. To conclude, our findings proved the capability of nanofibers in loading BT and improving its repurposed antimicrobial efficacy. Therefore, it could be a promising carrier for BT to be used in combating numerous human pathogens.

Anisotropic 3D scaffolds for spinal cord guided repair: Current concepts

A spinal cord injury (SCI) can be caused by unforeseen events such as a fall, a vehicle accident, a gunshot, or a malignant illness, which has a significant impact on the quality of life of the patient. Due to the limited regenerative potential of the central nervous system (CNS), SCI is one of the most daunting medical challenges of modern medicine. Great advances have been made in tissue engineering and regenerative medicine, which include the transition from two-dimensional (2D) to three-dimensional (3D) biomaterials. Combinatory treatments that use 3D scaffolds may significantly enhance the repair and regeneration of functional neural tissue. In an effort to mimic the chemical and physical properties of neural tissue, scientists are researching the development of the ideal scaffold made of synthetic and/or natural polymers. Moreover, in order to restore the architecture and function of neural networks, 3D scaffolds with anisotropic properties that replicate the native longitudinal orientation of spinal cord nerve fibres are being designed. In an effort to determine if scaffold anisotropy is a crucial property for neural tissue regeneration, this review focuses on the most current technological developments relevant to anisotropic scaffolds for SCI. Special consideration is given to the architectural characteristics of scaffolds containing axially oriented fibres, channels, and pores. By analysing neural cell behaviour in vitro and tissue integration and functional recovery in animal models of SCI, the therapeutic efficacy is evaluated for its successes and limitations.

Optimistic and possible contribution of nanomaterial on biomedical applications: A review

Nanomaterials have many advantages over bulk materials, including enhanced surface-to-volume proportion as well as magnetic traits. It has been a steady rise in research with using nanomaterials in various biomedical fields in the past few decades. Constructing nanomaterials has emerged as a leading research primary concern in order to discover specialized biomedical applications. Since, their advantageous properties including chemical stability, non-toxicity, bio - compatibility, relatively high magnetization, and strong magnetic vulnerability, nanoparticles of iron oxide had already influenced implementations in different biomedical fields. Nanomaterials can be divided up into four nanomaterials such as metallic nanomaterials, bimetallic or alloy nanomaterials, metal oxide nanomaterials, as well as magnetic nanomaterials. Hence, the purpose of this review is to conduct such in discussion on emerging advancements in nanomaterials for biomedical, with such a special emphasis upon those options of nanomaterials including metallic nanomaterials: Au and Ag, bimetallic nanomaterials: Fe-Co and Fe-Pt, and metal oxides: TiO₂ and CeO₂. Securing this information gap will result in a better comprehension of the contribution of nanomaterial type and subsequent huge-scale applications in aspects of both their potential and challenges.

Hybrid Systems of Nanofibers and Polymeric Nanoparticles for Biological Application and Delivery Systems

Nanomedicine is a new discipline resulting from the combination of nanotechnology and biomedicine. Nanomedicine has contributed to the development of new and improved treatments, diagnoses, and therapies. In this field, nanoparticles have notable importance due to their unique properties and characteristics, which are useful in different applications, including tissue engineering, biomarkers, and drug delivery systems. Electrospinning is a versatile technique used to produce fibrous mats. The high surface area of the electrospun mats makes them suitable for applications in fields using nanoparticles. Electrospun mats are used for tissue engineering, wound dressing, water-treatment filters, biosensors, nanocomposites, medical implants, protective clothing materials, cosmetics, and drug delivery systems. The combination of nanoparticles with nanofibers creates hybrid systems that acquire properties that differ from their components' characteristics. By utilizing nanoparticles and nanofibers composed of dissimilar polymers, the two synergize to improve the overall performance of electrospinning mats and nanoparticles. This review summarizes the hybrid systems of polymeric nanoparticles and polymeric nanofibers, critically analyzing how the combination improves the properties of the materials and contributes to the reduction of some disadvantages found in nanometric devices and systems.

Doxorubicin-Loaded Multivesicular Liposomes (DepoFoam) as a Sustained Release Carrier Intended for Locoregional Delivery in Cancer Treatment: Development, Characterization, and Cytotoxicity Evaluation

Background

Despite the advantages of direct intratumoral (IT) injection, the relatively rapid withdrawal of most anti-cancer drugs from the tumor due to their small molecular size limits the effectiveness of this method of administration. To address these limitations, recently, increasing attention has been directed to using slow-release biodegradable delivery systems for IT injection.

Objectives

This study aimed to develop and characterize a doxorubicin-loaded DepoFoam system as an efficient controlled-release carrier to be employed for locoregional drug delivery in cancer treatment.

Methods

Major formulation parameters, including the molar ratio of cholesterol to the main lipid [Chol/egg phosphatidylcholine (EPC)], triolein (TO) content, and lipid-to-drug molar ratio (L/D), were optimized using a two-level factorial design approach. The prepared batches were evaluated for encapsulation efficiency (EE) and percentage of drug release (DR) after 6 and 72 hours as dependent variables. The optimum formulation (named DepoDOX) was further evaluated in terms of particle size, morphology, zeta potential, stability, Fourier-transform infrared spectroscopy, in vitro cytotoxicity, and hemolysis.

Results

The analysis of factorial design indicated that TO content and L/D ratio had a negative effect on EE; between these two, TO content had the greatest effect. The TO content was also the most significant component, with a negative effect on the release rate. The ratio of Chol/EPC showed a dual effect on the DR rate. Using a higher percentage of Chol slowed down the initial release phase of the drug; nevertheless, it accelerated the DR rate in the later slow phase. DepoDOX were spherical and honeycomb-like structures (≈ 9.81 μm) with a desired sustained release profile, as DR lasted 11 days. Its biocompatibility was confirmed by the results of cytotoxicity and hemolysis assays.

Conclusions

The in vitro characterization of optimized DepoFoam formulation demonstrated its suitability for direct locoregional delivery. DepoDOX, as a biocompatible lipid-based formulation, showed appropriate particle size, high capability for encapsulating doxorubicin, superior physical stability, and a markedly prolonged DR rate. Therefore, this formulation could be considered a promising candidate for locoregional drug delivery in cancer treatment.

An injectable hyperthermic nanofiber mesh with switchable drug release to stimulate chemotherapy potency

We developed a smart nanofiber mesh (SNM) with anticancer abilities as well as injectability and fast recovery from irregular to non-compressible shapes. The mesh can be injected at the tumor site to modulate and control anticancer effects by loading the chemotherapeutic drug, paclitaxel (PTX), as well as magnetic nanoparticles (MNPs). The storage modulus of the mesh decreases when applied with a certain shear strain, and the mesh can pass through a 14-gauge needle. Moreover, the fibrous morphology is maintained even after injection. In heat-generation measurements, the mesh achieved an effective temperature of mild hyperthermia (41-43°C) within 5 min of exposure to alternating magnetic field (AMF) irradiation. An electrospinning method was employed to fabricate the mesh using a copolymer of N-isopropylacrylamide (NIPAAm) and N-hydroxyethyl acrylamide (HMAAm), whose phase transition temperature was adjusted to a mildly hyperthermic temperature range. Pplyvinyl alcohol (PVA) was also incorporated to add shear-thinning property to the interactions between polymer chains derived from hydrogen bonding, The "on-off" switchable release of PTX from the mesh was detected by the drug release test. Approximately 73% of loaded PTX was released from the mesh after eight cycles, whereas only a tiny amount of PTX was released during the cooling phase. Furthermore, hyperthermia combined with chemotherapy after exposure to an AMF showed significantly reduced cancer cell survival compared to the control group. Subsequent investigations have proven that a new injectable local hyperthermia chemotherapy platform could be developed for cancer treatment using this SNM.

Electrospun Fibers: Versatile Approaches for Controlled Release Applications

Electrospinning has been one of the most attractive methods of fiber fabrication in the last century. A lot of studies have been conducted, especially in tissue engineering and drug delivery using electrospun fibers. Loading many different drugs and bioactive agents on or within these fibers potentiates the efficacy of such systems; however, there are still no commercial products with this technology available in the market. Various methods have been developed to improve the mechanical and physicochemical behavior of structures toward more controllable delivery systems in terms of time, place, or quantity of release. In this study, most frequent methods used for the fabrication of controlled release electrospun fibers have been reviewed. Although there are a lot of achievements in the fabrication of controlled release fibers, there are still many challenges to be solved to reach a qualified, reproducible system applicable in the pharmaceutical industry.

Cellular landscaping of cisplatin resistance in cervical cancer

Cervical cancer (CC) caused by human papillomavirus (HPV) is one of the largest causes of malignancies in women worldwide. Cisplatin is one of the widely used drugs for the treatment of CC is rendered ineffective owing to drug resistance. This review highlights the cause of resistance and the mechanism of cisplatin resistance cells in CC to develop therapeutic ventures and strategies that could be utilized to overcome the aforementioned issue. These strategies would include the application of nanocarries, miRNA, CRIPSR/Cas system, and chemotherapeutics in synergy with cisplatin to not only overcome the issues of drug resistance but also enhance its anti-cancer efficiency. Moreover, we have also discussed the signaling network of cisplatin resistance cells in CC that would provide insights to develop therapeutic target sites and inhibitors. Furthermore, we have discussed the role of CC metabolism on cisplatin resistance cells and the physical and biological factors affecting the tumor microenvironments.

Impact of cancer on mortality rates in patients with sepsis: A meta-analysis and meta-regression of current studies

BACKGROUND

Research suggests that approximately 6% of adult patients admitted to hospitals in the United States present with sepsis and there has been a minimal change in the incidence of this condition in the last decade. Furthermore, patients with cancer generally have a higher incidence of sepsis due to immunosuppression caused by cancer or its treatment.

AIM

To assess if cancer increases the mortality rates in sepsis patients by pooling evidence from contemporary studies.

METHODS

PubMed, Embase, and Google Scholar databases were searched from January 1, 2001 to December 15, 2021 for studies comparing outcomes of sepsis patients based on the presence of active cancer. Mortality data were pooled using a random-effects model, with the odds ratio (OR) and 95% confidence interval (CI) calculated. Meta-regression was conducted to assess the influence of confounders on mortality rates.

RESULTS

Nine studies were included. The meta-analysis demonstrated a non-significant tendency towards increased risk of early mortality (OR = 2.77, 95%CI: 0.88-8.66, I² = 99%) and a statistically significantly increased risk of late mortality amongst sepsis patients with cancer as compared to non-cancer sepsis patients (OR = 2.46, 95%CI: 1.42-4.25, I² = 99%). Overall, cancer was found to significantly increase the risk of mortality in sepsis patients (OR = 2.7, 95%CI: 1.07-6.84, I² = 99%). Meta-analysis indicated a statistically significantly increased risk of mortality in patients with solid tumors as well as hematological malignancies. Meta-regression indicated that an increase in the prevalence of comorbid pulmonary and renal diseases increased the risk of mortality in cancer patients with sepsis. Mortality rates increased with an increase in the percentage of patients with urinary tract infections while an inverse relationship was seen for infections of cutaneous origin.

CONCLUSION

Contemporary evidence indicates that the presence of any cancer in sepsis patients significantly increases the risk of mortality. Scarce data suggest that mortality is equally increased for both solid and hematological cancers. Current evidence is limited by high heterogeneity and there is a need for further studies taking into account several confounding variables to present better evidence.

Formulation of Levocetirizine-Loaded Core–Shell Type Nanofibrous Orally Dissolving Webs as a Potential Alternative for Immediate Release Dosage Forms

Several applications of nanofiber-based systems are based on their corresponding functionality-related properties, which often cannot be satisfied by a fiber web with a monolithic structure because of the various physicochemical properties and amounts of embedded compounds. Therefore, one of the main directions in the development of fiber systems is creating core–shell type complex fiber structures that can provide application-specific properties to the fiber matrix. The present study aimed to formulate levocetirizine-loaded core–shell type hydrophilic polymer-based fibrous systems. The core phase contained the antihistamine levocetirizine, while the permeation enhancer (Na-taurocholate), the local pH regulator (citric acid), and the cyclodextrin used as a taste masking agent were included in the shell phase of the fibrous formulation. Scanning electron microscopy images indicated that a randomly oriented homogeneous fibrous structure was obtained, while the Raman mapping and chemometric analysis confirmed the partially formed core–shell structure. A fast release rate of the antihistamine drug from the complex structural fibrous system was obtained (within 1 min complete dissolution can be observed) due to its increased surface area to volume ratio and its more favorable wettability properties, which consequently allows for more erosion. The masking properties against the unpleasant bitter taste of API of the formulated complex nanostructure were confirmed by the results of the electronic tongue. The formulated complex nanostructure enabled fast and complete release of the API, providing a potential enhancement in the rate and extent of absorption while masking the unpleasant taste of levocetirizine, which has a high impact on the patient adherence. All in all, the results show that the developed orally dissolving fibrous web formulation can be a potential alternative to the commercially available orally disintegrating tablets.

Development of stimulus-sensitive electrospun membranes based on novel biodegradable segmented polyurethane as triggered delivery system for doxorubicin

In this work, redox-sensitive polyurethane urea (PUU) based electrospun membranes have been exploited to chemically tether a pH-sensitive doxorubicin derivative achieved by linking a lipoyl hydrazide to the drug via a hydrazone linkage. First, the lipoyl-hydrazone-doxorubicin derivative labelled as LA-Hy-Doxo has been synthesized and characterized. Then, the molecule has been tethered, via a thiol-disulfide exchange reaction, to the redox-sensitive PUU (PolyCEGS) electrospun membrane. The redox-sensitive PolyCEGS PUU has been produced by using PCL-PEG-PCL polyol and glutathione-tetramethyl ester (GSSG-OMe)₄ as a chain extender. The LA-Hy-Doxo tethered electrospun membrane has showed a dually controlled release triggered by acidic and reducing conditions, producing a significant cytotoxic effect in human breast cancer cell lines (MCF-7) which has validated the system for the post-surgical treatment of solid tumors to contrast recurrence.

Drug Delivery Applications of Coaxial Electrospun Nanofibres in Cancer Therapy

Cancer is one of the most serious health problems and the second leading cause of death worldwide, and with an ageing and growing population, problems related to cancer will continue. In the battle against cancer, many therapies and anticancer drugs have been developed. Chemotherapy and relevant drugs are widely used in clinical practice; however, their applications are always accompanied by severe side effects. In recent years, the drug delivery system has been improved by nanotechnology to reduce the adverse effects of the delivered drugs. Among the different candidates, core-sheath nanofibres prepared by coaxial electrospinning are outstanding due to their unique properties, including their large surface area, high encapsulation efficiency, good mechanical property, multidrug loading capacity, and ability to govern drug release kinetics. Therefore, encapsulating drugs in coaxial electrospun nanofibres is a desirable method for controlled and sustained drug release. This review summarises the drug delivery applications of coaxial electrospun nanofibres with different structures and drugs for various cancer treatments.

Drug Delivery Systems for Photodynamic Therapy: The Potentiality and Versatility of Electrospun Nanofibers

Recently, photodynamic therapy (PDT) has become a promising approach for the treatment of a broad range of diseases, including oncological and infectious diseases. This minimally invasive and localized therapy is based on the production of reactive oxygen species (ROS) able to destroy cancer cells and inactivate pathogens by combining the use of photosensitizers (PSs), light and molecular oxygen. To overcome the drawbacks of drug systemic administration, drug delivery systems (DDS) can be used to carrier the PSs, allowing higher therapeutic efficacy and minimal toxicological effects. Polymeric nanofibers produced by electrospinning emerged as powerful platforms for drug delivery applications. Electrospun nanofibers exhibit outstanding characteristics, such as large surface area to volume ratio associated with high drug loading, high porosity, flexibility, ability to incorporate and release a wide variety of therapeutic agents, biocompatibility and biodegradability. Due to the versatility of this technique, fibers with different morphologies and functionalities, including drug release profile can be produced. The possibility of scalability makes electrospinning even more attractive for the development of DDS. This review aims to explore and show an up to date of the huge potential of electrospun nanofibers as DDS for different PDT applications and discuss the opportunities and challenges in this field. This article is protected by copyright. All rights reserved.

Electrospun Nanofibers Revisited: An Update on the Emerging Applications in Nanomedicine

Electrospinning (ES) has become a straightforward and customizable drug delivery technique for fabricating drug-loaded nanofibers (NFs) using various biodegradable and non-biodegradable polymers. One of NF's pros is to provide a controlled drug release through managing the NF structure by changing the spinneret type and nature of the used polymer. Electrospun NFs are employed as implants in several applications including, cancer therapy, microbial infections, and regenerative medicine. These implants facilitate a unique local delivery of chemotherapy because of their high loading capability, wide surface area, and cost-effectiveness. Multi-drug combination, magnetic, thermal, and gene therapies are promising strategies for improving chemotherapeutic efficiency. In addition, implants are recognized as an effective antimicrobial drug delivery system overriding drawbacks of traditional antibiotic administration routes such as their bioavailability and dosage levels. Recently, a sophisticated strategy has emerged for wound healing by producing biomimetic nanofibrous materials with clinically relevant properties and desirable loading capability with regenerative agents. Electrospun NFs have proposed unique solutions, including pelvic organ prolapse treatment, viable alternatives to surgical operations, and dental tissue regeneration. Conventional ES setups include difficult-assembled mega-sized equipment producing bulky matrices with inadequate stability and storage. Lately, there has become an increasing need for portable ES devices using completely available off-shelf materials to yield highly-efficient NFs for dressing wounds and rapid hemostasis. This review covers recent updates on electrospun NFs in nanomedicine applications. ES of biopolymers and drugs is discussed regarding their current scope and future outlook.

Electrospun nanofibers modified with zeolitic imidazolate framework-8 for electrochemiluminescent determination of terbutaline

For the first time it is demonstrated that zeolitic imidazolate framework-8 electrospun nanofibers (ZIF-8 NF) could serve as electrochemiluminescence (ECL) accelerator for the facile detection of terbutaline residual. A novel ECL sensor for the determination of terbutaline was fabricated based on ZIF-8 NF. The ZIF-8 NF were successfully prepared according to electrospinning and in-situ growth method. First, chitosan was modified on the surface of the electrode, and then the ZIF-8 NF was modified onto the upper layer of the chitosan. Taking advantages of chitosan and ZIF-8 NF in conductivity and electrocatalysis, the modified electrode presents obvious ECL phenomenon in 0.2 M PBS solution (pH 10.0) containing 0.025 M luminol. After the addition of terbutaline, ECL intensity decreased significantly, and the decreasing value showed a linear relationship with the logarithm of terbutaline concentration. The linear range was from 2.0 × 10^-10 to 2.0 × 10^-5 M, and the detection limit was 1.41 × 10^-11 M (3σ/m). The method had high sensitivity, good stability, and good applicability to actual pork samples.

Adsorption, and controlled release of doxorubicin from cellulose acetate/polyurethane/multi-walled carbon nanotubes composite nanofibers

The cellulose acetate (CA)/poly (ε-caprolactone diol)/poly (tetramethylene ether) glycol-polyurethane (PCL-Diol/PTMG-PU)/multi-walled carbon nanotubes (MWCNTs) composite nanofibers were prepared via two-nozzle electrospinning on both counter sides of the collector. The performance of synthesized composite nanofibers was investigated as an environmental application and anticancer delivery system for the adsorption/release of doxorubicin (DOX). The synergic effect of MWCNTs and DOX incorporated into the nanofibers was investigated against LNCaP prostate cancer cells. The status of MWCNTs and DOX in composite nanofibers was demonstrated by SEM, FTIR and UV-vis determinations. The adsorption tests using nanofibrous adsorbent toward DOX sorption was evaluated under various DOX initial concentrations (100-2000 mg l^-1), adsorption times (5-120 min), and pH values (pH:2-9). Due to the fitting of isotherm and kinetic data with Redlich-Peterson and pseudo-second order models, both chemisorption and surface adsorption of DOX molecules mechanisms have been predicted. The drug release from both nanofibers and MWCNTs-loaded nanofibers was compared. The better drug sustained release profiles verified in the presence of composite nanofibers. LNCaP prostate cancer and L929 normal cells were treated to investigate the cytotoxicity and compatibility of synthesized composite nanofibers. The apoptosis/necrosis of hybrid nanofibers and MWCNTs loaded-nanofibers was investigated. The obtained results demonstrated the synergic effects of MWCNTs and DOX loaded-nanofibers on the LNCaP prostate cancer cells death.

Effects of emulsion, dispersion, and blend electrospinning on hyaluronic acid nanofibers with incorporated antiseptics

Nanofibrous materials are used in drug delivery as carriers of active ingredients. These can be incorporated into the materials with various electrospinning methods that differ mainly in the way spinning solutions are prepared. Each method affects primarily the encapsulation efficiency and distribution of active ingredients in the materials. This study focuses on the incorporation of octenidine dihydrochloride (OCT) and triclosan (TRI) into nanofibrous materials electrospun from native hyaluronic acid emulsions, dispersions, and blends. OCT had no substantial effect on fiber morphology, which is affected by the solvent system. All OCT encapsulation efficiencies were comparable (approximately 90%). TRI encapsulation efficiencies varied greatly depending on the method used. Merely 3% of TRI was encapsulated when it was spun from a dispersion. Encapsulation efficiency was higher, and TRI was incorporated in clusters when an emulsion was used. The best result was achieved with a blend, in which case 96% of TRI was encapsulated.

Implantable magnetic nanofibers with ON-OFF switchable release of curcumin for possible local hyperthermic chemotherapy of melanoma

Implantable thermo-responsive drug-loaded magnetic nanofibers (NFs) have attracted great interest for localized thermo-chemotherapy of cancer tissue/cells. From this perspective, smart polymeric electrospun NFs co-loaded with magnetic nanoparticles (MNPs) and a natural polyphenol anticancer agent, curcumin (CUR), were developed to enhance the local hyperthermic chemotherapy against melanoma, the most serious type of skin cancer. CUR/MNPs-loaded thermo-sensitive electrospun NFs exhibited alternating magnetic field (AMF)-responsive heat generation and "ON-OFF" switchable heating capability. Besides, corresponding to the reversible alterations in the swelling ratio, the "ON-OFF" switchable discharge of CUR from the magnetic NFs was detected in response to the "ON-OFF" switching of AMF application. Due to the combinatorial effect of hyperthermia and release of CUR after applying an AMF ("ON" state) for 600 s on the second and third days of incubation time, the viability of the B16F10 melanoma cancer cells exposed to the CUR/MNPs-NFs was reduced by 40% and 17%, respectively. Taken together, the macroscopic and nanoscale features of the smart NFs led to the creation of a reversibly adjustable structure that enabled hyperthermia and facile switchable release of CUR for eradication of melanoma cancer cells.

2D Nanosheets-A New Class of Therapeutic Formulations against Cancer

Researchers in cancer nanomedicine are exploring a revolutionary multifaceted carrier for treatment and diagnosis, resulting in the proposal of various drug cargos or "magic bullets" in this past decade. Even though different nano-based complexes are registered for clinical trials, very few products enter the final stages each year because of various issues. This prevents the formulations from entering the market and being accessible to patients. In the search for novel materials, the exploitation of 2D nanosheets, including but not limited to the highly acclaimed graphene, has created extensive interest for biomedical applications. A unique set of properties often characterize 2D materials, including semiconductivity, high surface area, and their chemical nature, which allow simple decoration and functionalization procedures, structures with high stability and targeting properties, vectors for controlled and sustained release of drugs, and materials for thermal-based therapies. This review discusses the challenges and opportunities of recently discovered 2D nanosheets for cancer therapeutics, with special attention paid to the most promising design technologies and their potential for clinical translation in the future.

Biotechnological Applications of Polymeric Nanofiber Platforms Loaded with Diverse Bioactive Materials

This review article highlights the critical research and formative works relating to nanofiber composites loaded with bioactive materials for diverse applications, and discusses the recent research on the use of electrospun nanofiber incorporating bioactive compounds such as essential oils, herbal bioactive components, plant extracts, and metallic nanoparticles. Inevitably, with the common advantages of bioactive components and polymer nanofibers, electrospun nanofibers containing bioactive components have attracted intense interests for their applications in biomedicine and cancer treatment. Many studies have only concentrated on the production and performance of electrospun nanofiber loaded with bioactive components; in this regard, the features of different types of electrospun nanofiber incorporating a wide variety of bioactive compounds and their developing trends are summarized and assessed in the present article, as is the feasible use of nanofiber technology to produce products on an industrial scale in different applications.

Polymeric long-acting drug delivery systems (LADDS) for treatment of chronic diseases: Inserts, patches, wafers, and implants

Non-oral long-acting drug delivery systems (LADDS) encompass a range of technologies for precisely delivering drug molecules into target tissues either through the systemic circulation or via localized injections for treating chronic diseases like diabetes, cancer, and brain disorders as well as for age-related eye diseases. LADDS have been shown to prolong drug release from 24 h up to 3 years depending on characteristics of the drug and delivery system. LADDS can offer potentially safer, more effective, and patient friendly treatment options compared to more invasive modes of drug administration such as repeated injections or minor surgical intervention. Whilst there is no single technology or definition that can comprehensively embrace LADDS; for the purposes of this review, these systems include solid implants, inserts, transdermal patches, wafers and in situ forming delivery systems. This review covers common chronic illnesses, where candidate drugs have been incorporated into LADDS, examples of marketed long-acting pharmaceuticals, as well as newly emerging technologies, used in the fabrication of LADDS.

Electrospun polyvinyl-alcohol/gum arabic nanofibers: Biomimetic platform for in vitro cell growth and cancer nanomedicine delivery

The design of powerful in vitro cell culture platforms to support precision medicine can contribute to predict therapeutic success of cancer patients. Electrospun nanofibers applied to cell culture can mimic extracellular matrix and improve in vitro cell behavior. Here, we describe biocompatible blended polyvinyl-alcohol (PVA)/gum arabic (GA) extracellular matrix (ECM)-like nanofibers for in vitro cell cultures capable of delivering nanocomposite for desired biomedical application. Therefore, PVA/GA ECM-like electrospun nanofibers were developed and characterized. Heat treatment was used to crosslink the nanofibers and biocompatibility was evaluated, which demonstrated the ability of developed platform to provide a cell culture-friendly environment. Previous work demonstrated that GA-gold nanoparticles (GA-AuNPs) in non-cytotoxic concentrations can reduce key metastatic cellular events such as invasion and colony formation of metastatic melanoma cells. Thus, crosslinked nanofibers were functionalized with GA-AuNPs and its cellular delivery was evaluated. GA-AuNPs were efficiently adsorbed onto the PVA/GA nanofibers surface and the system effectively delivered the nanocomposites to metastatic melanoma cells. In conclusion, the described biocompatible system could be prospected as a valuable in vitro tool for precision medicine.

Dual drug release mechanisms through mesoporous silica nanoparticle/electrospun nanofiber for enhanced anticancer efficiency of curcumin

Electrospun nanofibers (NFs)-based drug delivery approaches are of particular interest as a hopeful implantable nanoplatform for localized cancer therapy and treating tissue defect after resection, allowing the on-site drug delivery with minimal side effect to healthy cells. To maintain therapeutic concentrations of anticancer molecules for a relatively long time through a combination of burst and sustained drug release mechanisms, a hybrid of polycaprolactone and gelatin (PCL/GEL) was used for co-encapsulation of free curcumin (CUR) and CUR-loaded mesoporous silica nanoparticles (CUR@MSNs) via electrospinning, resulting in a novel drug-loaded nanofibrous scaffold, CUR/CUR@MSNs-NFs. The as-prepared MSNs and composite NFs were characterized via TGA, FTIR, FE-SEM, TEM, and BET. In vitro release profile of CUR from CUR/CUR@MSNs-NFs was examined, and the in vitro antitumor efficacy against MDA-MB-231 breast cancer cells was also evaluated through MTT, scratch assay, DAPI staining, and real-time PCR. The results disclosed that the smooth, bead-free, and randomly oriented CUR/CUR@MSNs-NFs displayed a combination of initial rapid discharge and sustained release for CUR, which led to higher cytotoxicity, lower migration as well as a more pronounced effect on apoptosis induction than CUR-NFs and CUR@MSNs-NFs. The present study illustrated that the dual drug release mechanisms through MSN/NF-mediated drug delivery systems might have a highly hopeful application as a localized implantable scaffold for potential postoperative breast cancer therapy.

Milestones and current achievements in development of multifunctional bioscaffolds for medical application

Tissue engineering (TE) is a rapidly growing interdisciplinary field, which aims to restore or improve lost tissue function. Despite that TE was introduced more than 20 years ago, innovative and more sophisticated trends and technologies point to new challenges and development. Current challenges involve the demand for multifunctional bioscaffolds which can stimulate tissue regrowth by biochemical curves, biomimetic patterns, active agents and proper cell types. For those purposes especially promising are carefully chosen primary cells or stem cells due to its high proliferative and differentiation potential. This review summarized a variety of recently reported advanced bioscaffolds which present new functions by combining polymers, nanomaterials, bioactive agents and cells depending on its desired application. In particular necessity of study biomaterial-cell interactions with in vitro cell culture models, and studies using animals with in vivo systems were discuss to permit the analysis of full material biocompatibility. Although these bioscaffolds have shown a significant therapeutic effect in nervous, cardiovascular and muscle, tissue engineering, there are still many remaining unsolved challenges for scaffolds improvement.

Prolonged proliferation and delayed senescence of the adipose-derived stem cells grown on the electrospun composite nanofiber co-encapsulated with TiO2 nanoparticles and metformin-loaded mesoporous silica nanoparticles

This study was aimed to investigate the effects of the Poly-ε-Caprolactone/Gelatin nanofibers (PCL/GEL NFs) co-encapsulated with TiO₂ nanoparticles (nTiO₂) and metformin-loaded mesoporous silica nanoparticles (MET@MSNs) on prolonging the in vitro expansion of human adipose-derived stem cells (hADSCs) without inducing cellular senescence and aging. FTIR, BET, FE-SEM, and TEM were applied to characterize the fabricated MET@MSNs and electrospun composite NFs. The presence of inorganic particles, nTiO₂ and MSNs, in the scaffolds improved their mechanical properties and led to a more sustained release of MET with almost the lack of the initial burst release from nTiO₂/MET@MSNs-loaded NFs. The enhanced adhesion, metabolic activity, and proliferation rate of the hADSCs grown on nTiO₂/MET@MSNs-loaded NFs were demonstrated via FE-SEM images, MTT test and PicoGreen assay, respectively, over 28 days of culture. Furthermore, the irregular nanofibrillar structures and the impact of sustained release of MET led to a significant upregulation in the mRNA levels of autophagy (Atg-5, Atg-7, Atg-12, and Beclin-1) and stemness (Nanog3, Sox-2, and Oct-4) markers as well as a considerable down-regulation of p16^INK4A senescence marker. Further, the upregulation of hTERT, enhanced activity of telomerase, and increased telomere length were more pronounced in the hADSCs cultured on nTiO₂/MET@MSNs-loaded NFs as compared to other types of NFs. Overall, our findings demonstrated the potential of the fabricated nanocomposite platform for counteracting cellular senescence and achieving sufficient quantities of fresh hADSCs with preserved stemness for various stem cell-based regenerative medicine purposes.

In Vitro Drug Release, Permeability, and Structural Test of Ciprofloxacin-Loaded Nanofibers

Nanofibers of the poorly water-soluble antibiotic ciprofloxacin (CIP) were fabricated in the form of an amorphous solid dispersion by using poly(vinyl pyrrolidone) as a polymer matrix, by the low-cost electrospinning method. The solubility of the nanofibers as well as their in vitro diffusion were remarkably higher than those of the CIP powder or the physical mixture of the two components. The fiber size and morphology were optimized, and it was found that the addition of the CIP to the electrospinning solution decreased the nanofiber diameter, leading to an increased specific surface area. Structural characterization confirmed the interactions between the drug and the polymer and the amorphous state of CIP inside the nanofibers. Since the solubility of CIP is pH-dependent, the in vitro solubility and dissolution studies were executed at different pH levels. The nanofiber sample with the finest morphology demonstrated a significant increase in solubility both in water and pH 7.4 buffer. Single medium and two-stage biorelevant dissolution studies were performed, and the release mechanism was described by mathematical models. Besides, in vitro diffusion from pH 6.8 to pH 7.4 notably increased when compared with the pure drug and physical mixture. Ciprofloxacin-loaded poly(vinyl pyrrolidone) (PVP) nanofibers can be considered as fast-dissolving formulations with improved physicochemical properties.

Electrospun Fibres of Chitosan/PVP for the Effective Chemotherapeutic Drug Delivery of 5-Fluorouracil

Electrospun nanofibrous mats consisting of chitosan (CS) and polyvinylpyrrolidone (PVP) were constructed. Tuning of solution and process parameters was performed and resulted in an electrospun system containing a 6:4 ratio of PVP:CS. This is a significant increase in the proportion of spun CS on the previously reported highest ratio PVP:CS blend. SEM analysis showed that the nanofibrous mats with 4 wt% CS/6 wt% PVP (sample E) comprised homogenous, uniform fibres with an average diameter of 0.569 μm. XPS analysis showed that the surface of the samples consisted of PVP. Raman and FTIR analysis revealed intermolecular interactions (via H-bonding) between PVP and CS. In FTIR spectra, the contribution of chitosan to CS/PVP complexes was shown by the downshift of the C=O band and by the linear increase in intensity of C-O stretching in CS. XPS analysis showed a smaller shift at the binding energy 531 eV, which relates to the amide of the acetylated functional groups. The obtained results demonstrate a sensitivity of Raman and FTIR tests to the presence of chitosan in PVP:CS blend. The chemotherapy drug 5-Fu was incorporated into the constructs and cell viability studies were performed. WST-8 viability assay showed that exposure of A549 human alveolar basal epithelial cells to 10 mg/mL 5-Fu loaded fibres was most effective at killing cells over 24 h. On the other hand, the constructs with loading of 1 mg/mL of drug were not efficient at killing A549 human alveolar basal epithelial cells. This study showed that CS/PVP/5-Fu constructs have potential in chemotherapeutic drug delivery systems.