Biocompatibility of a self-assembled glycol chitosan nanogel

The research of chitosan-based nanogel for biomedical applications has grown exponentially in the last years; however, its biocompatibility is still insufficiently reported. Hence, the present work provides a thorough study of the biocompatibility of a glycol chitosan (GC) nanogel. The obtained results showed that GC nanogel induced slight decrease on metabolic activity of RAW, 3T3 and HMEC cell cultures, although no effect on cell membrane integrity was verified. The nanogel does not promote cell death by apoptosis and/or necrosis, exception made for the HMEC cell line challenged with the higher GC nanogel concentration. Cell cycle arrest on G1 phase was observed only in the case of RAW cells. Remarkably, the nanogel is poorly internalized by bone marrow derived macrophages and does not trigger the activation of the complement system. GC nanogel blood compatibility was confirmed through haemolysis and whole blood clotting time assays. Overall, the results demonstrated the safety of the use of the GC nanogel as drug delivery system.Paula Pereira thanks FCT, the Ph.D. grant ref SFRH/BD/64977/2009. This work was also supported by a grant from the Spanish Ministry of Economy and Competitivity (SAF2011-30337-C02-02). We also acknowledge the European Union Seventh Framework Programme [FP7/REGPOT-2012-2013.1] under grant agreement BIOCAPS-316265. MP acknowledges fellowship from Spanish Ministry of Education (FPU predoctoral grant program)

Development and validation of an HPLC method for the determination of fluorouracil in polymeric nanoparticles

The objective of this work was to develop and validate a rapid high performance liquid chromatography (HPLC) method for the quantitative analysis of fluorouracil (5-FU) in polymeric nanoparticles. Chromatographic analyses were performed on an RP C18 column with a mobile phase consisting of acetonitrile and water (10:90, v/v) at a flow rate of 1 mL/min. The 5-FU was detected and quantitated using a photodiode array detector at a wavelength of 265 nm. The method was shown to be specific and linear in the range of 0.1-10 µg/mL (r = 0.9997). The precision (intra- and inter-day) was demonstrated because the maximum relative standard deviation was 3.51%. The method is robust relative to changes in flow rate, column and temperature. The limits of detection and quantitation were 10.86 and 32.78 ng/mL, respectively. The method fulfilled the requirements for reliability and feasibility for application to the quantitative analysis of 5-FU in polymeric nanoparticles.O objetivo deste trabalho foi desenvolver e validar um método rápido de cromatografia líquida de alta eficiência (CLAE) para análise quantitativa de fluorouracila (5-FU) em nanopartículas poliméricas. Corridas cromatográficas foram realizadas sob uma coluna RP C18 com uma fase móvel consistindo de acetonitrila e água (10:90, v/v) a um fluxo de 1 mL/min. O 5-FU foi detectado e quantificado através de um detector de fotodiodos em um comprimento de onda de 265 nm. O método demonstrou ser específico e linear na faixa de 0,1-10 µg/mL (r =0.9997). As precisões (intra e inter dia) revelaram um desvio padrão relativo máximo de 3,51%. O método é robusto considerando mudanças realizadas no fluxo da fase móvel, temperatura e marca da coluna. Os limites de detecção e quantificação foram de 10,86 e 32,78 ng/mL, respectivamente. O método cumpriu os requisitos para ser considerado confiável e viável para aplicação na análise quantitativa de 5-FU em nanopartículas poliméricas

Bio-Inorganic Layered Double Hydroxide Nanohybrids in Photochemotherapy: A Mini Review

Clay-based bio-inorganic nanohybrids, such as layered double hydroxides (LDH), have been extensively researched in the various fields of biomedicine, particularly for drug delivery and bio-imaging applications. Recent trends indicate that such two-dimensional LDH can be hybridized with a variety of photo-active biomolecules to selectively achieve anti-cancer benefits through numerous photo/chemotherapies (PCT), including photothermal therapy, photodynamic therapy, and magnetic hyperthermia, a combination of therapies to achieve the best treatment regimen for patients that cannot be treated either by surgery or radiation alone. Among the novel two-dimensional clay-based bio-inorganic nanohybrids, LDH could enhance the photo-stability and drug release controllability of the PCT agents, which would, in turn, improve the overall phototherapeutic performance. This review article highlights the most recent advances in LDH-based two-dimensional clay-bio-inorganic nanohybrids for the aforementioned applications

Recent Developments on Semiconducting Polymer Nanoparticles as Smart Photo-Therapeutic Agents for Cancer Treatments—A Review

Semiconducting polymer nanoparticles (SPN) have been emerging as novel functional nano materials for phototherapy which includes PTT (photo-thermal therapy), PDT (photodynamic therapy), and their combination. Therefore, it is important to look into their recent developments and further explorations specifically in cancer treatment. Therefore, the present review describes novel semiconducting polymers at the nanoscale, along with their applications and limitations with a specific emphasis on future perspectives. Special focus is given on emerging and trending semiconducting polymeric nanoparticles in this review based on the research findings that have been published mostly within the last five years

Polyphosphazene-Based Biomaterials for Biomedical Applications

Recently, synthetic polymers have attracted great interest in the field of biomedical science. Among these, polyphosphazenes (PPZs) are regarded as one of the most promising materials, due to their structural flexibility and biodegradability compared to other materials. PPZs have been developed through numerous studies. In particular, multi-functionalized PPZs have been proven to be potential biomaterials in various forms, such as nanoparticles (NPs) and hydrogels, through the introduction of various functional groups. Thus, PPZs have been applied for the delivery of therapeutic molecules (low molecular weight drugs, genes and proteins), bioimaging, phototherapy, bone regeneration, dental liners, modifiers and medical devices. The main goal of the present review is to highlight the recent and the most notable existing PPZ-based biomaterials for aforementioned applications, with future perspectives in mind

Multifunctional Polymeric Micelles for Cancer Therapy

Polymeric micelles, nanosized assemblies of amphiphilic polymers with a core–shell architecture, have been used as carriers for various therapeutic compounds. They have gained attention due to specific properties such as their capacity to solubilize poorly water-soluble drugs, biocompatibility, and the ability to accumulate in tumor via enhanced permeability and retention (EPR). Moreover, additional functionality can be provided to the micelles by a further modification. For example, micelle surface modification with targeting ligands allows a specific targeting and enhanced tumor accumulation. The introduction of stimuli-sensitive groups leads to the drug’s release in response to environment change. This review highlights the progress in the development of multifunctional polymeric micelles in the field of cancer therapy. This review will also cover some examples of multifunctional polymeric micelles that are applied for tumor imaging and theragnosis

Stimuli-Responsive Polypeptides for Biomedical Applications

Stimuli-responsive polypeptides have gained attention because desirable bioactive properties can be easily imparted to them while keeping their biocompatibility and biodegradability intact. In this review, we summarize the most recent advances in various stimuli-responsive polypeptides (pH, reduction, oxidation, glucose, adenosine triphosphate (ATP), and enzyme) over the past five years. Various synthetic strategies exploited for advanced polypeptide-based materials are introduced, and their applicability in biomedical fields is discussed. The recent polypeptides imparted with new stimuli-responsiveness and their novel chemical and physical properties are explained in this review