Molecularly Imprinted Membrane Produced by Electrospinning for β-Caryophyllene Extraction

Molecularly imprinted membrane of β-caryophyllene (MIM-βCP) was fabricated incorporating β-caryophyllene molecularly imprinted polymer nanoparticles (βCP-NP) into polycaprolactone (PCL) fibers via electrospinning. The βCP-NP were synthesized by precipitation polymerization using the βCP as a template molecule and acrylic acid as a functional monomer in the proportion of 1:4 mol, respectively. Atomic force microscopy images and X-ray diffraction confirmed the nanoparticles' incorporation into MIM-βCP. MIM-βCP functionalization was evaluated by gas chromatography. The binding capacity was 1.80 ± 0.05 μmol/cm², and the selectivity test was performed with a mixing solution of βCP and caryophyllene oxide, as an analog compound, that extracted 77% of the βCP in 5 min. The electrospun MIM-βCP can be used to detect and extract the βCP, applications in the molecular sieve, and biosensor production and may also contribute as an initial methodology to enhance versatile applications in the future, such as in the treatment of skin diseases, filters for extraction, and detection of βCP to prevent counterfeiting of commercial products, and smart clothing with insect-repellent properties.

Virucidal PVP-Copper Salt Composites against Coronavirus Produced by Electrospinning and Electrospraying

Electrospinning technology was used to produced polyvinylpyrrolidone (PVP)-copper salt composites with structural differences, and their virucidal activity against coronavirus was investigated. The solutions were prepared with 20, 13.3, 10, and 6.6% w/v PVP containing 3, 1.0, 0.6, and 0.2% w/v Cu (II), respectively. The rheological properties and electrical conductivity contributing to the formation of the morphologies of the composite materials were observed by scanning electron microscopy (SEM). SEM images revealed the formation of electrospun PVP-copper salt ultrafine composite fibers (0.80 ± 0.35 µm) and electrosprayed PVP-copper salt composite microparticles (1.50 ± 0.70 µm). Energy-dispersive X-ray spectroscopy (EDS) evidenced the incorporation of copper into the produced composite materials. IR spectra confirmed the chemical composition and showed an interaction of Cu (II) ions with oxygen in the PVP resonant ring. Virucidal composite fibers inactivated 99.999% of coronavirus within 5 min of contact time, with moderate cytotoxicity to L929 cells, whereas the virucidal composite microparticles presented with a virucidal efficiency of 99.999% within 1440 min of exposure, with low cytotoxicity to L929 cells (mouse fibroblast). This produced virucidal composite materials have the potential to be applied in respirators, personal protective equipment, self-cleaning surfaces, and to fabric coat personal protective equipment against SARS-CoV-2, viral outbreaks, or pandemics.

Highly sensitive electrochemical immunosensor using a protein-polyvinylidene fluoride nanocomposite for human thyroglobulin

The highly sensitive detection of serum thyroglobulin (Tg) is essential in the post-treatment follow-up of patients with differentiated thyroid cancer undergoing total or partial thyroidectomy and radioactive iodine ablation and requires sensitive, accurate and stable methods. This work proposes an electrochemical immunosensor for the detection of serum Tg antigen, making use of innovative nanocomposites including polyvinylidene fluoride (PVDF) microparticles coated with streptavidin (MP) and gold nanoparticles (AuNPs). The functionalized polymer matrices were characterized by UV-Vis, FTIR, XPS, SEM, dynamic light scattering, and free surface energy. Immobilization of biotin-labeled anti-thyroglobulin monoclonal antibodies was achieved by binding these to the polymer nanocomposite via streptavidin proteins. The analytical response was measured in quintuplicate and had a linear profile from 2.0 to 10.0 ng/mL Tg, with r² of 0.985. The limits of detection and quantification were excellent, equal to 0.015 and 0.047 ng/mL, respectively. In addition, the recovery factor was equal to 95.4% (1.0 ng/mL Tg). Overall, the innovative polymer-based nanocomposite used herein enabled the production of an electrochemical-based immunosensor with excellent sensitivity, selectivity, and reproducibility. It evidenced the remarkable potential of determining low levels of Tg in in vitro assays, thereby suggesting that it may be considered for the analyzes of serum patients.

α-amyrin-loaded nanocapsules produce selective cytotoxic activity in leukemic cells

INTRODUCTION

Amyrins are triterpenes that have attractive pharmacological potential; however, their low water solubility and erratic stomach absorption hinders their use as a drug. The aim of this paper was to develop a novel α-amyrin-loaded nanocapsule for intestinal delivery and evaluate, preliminarily, its cytotoxic ability against leukemic cells.

MATERIAL AND METHODS

Five nanocapsule formulations were designed by the solvent displacement-evaporation method. Poly-ε-caprolactone, Eudragit® E100, and Kollicoat® Mae 100 P were used as film-former materials. Particle size, polydispersity index (PdI), zeta potential, and the pH of all formulations were measured. The cytotoxic potential of the nanocapsules was evaluated in vitro using different leukemic lineages RESULTS: Nanocapsules coated with Kollicoat® Mae 100 P presented the smallest particle size (130 nm), the lowest zeta-potential (-38 mV), and the narrowest size distribution (PdI = 0.100). The entrapment efficiency was 65.47%, while the loading capacity was 2.40%. Nanocapsules release 100% of α-amyrin in 40 min (pH 7.4), by using a possible mechanism of swelling-diffusion. The formulation showed excellent on-shelf physicochemical stability during one year. Additionally, nanocapsules produced a selective cytotoxic effect on a human leukemia lineage Kasumi-1, an acute myeloid leukemia cell line, and produced cell death by apoptosis CONCLUSION: α-amyrin-loaded nanocapsules appear to be a promising nanoformulation that could be used against leukemia.

Novel electrochemical sensor based on molecularly imprinted polymer for selective recognition of sesquiterpene β-caryophyllene

Molecularly imprinted polymers provide an excellent platform for the modification of selective electrodes for sensing applications. Herein, we present a novel modified carbon paste electrode (CPE) with a selective molecularly imprinted polymer (MIP) for recognition of sesquiterpene β-caryophyllene, constituted of important plants oil-resins and extracts. The non-covalent MIP was synthesized using AA, EGDMA, and AIBN as a functional monomer, cross-linker and initiator agent, respectively. Structural and chemical characterization of the synthesized MIP was conducted through scanning electron microscopy (SEM), Fourier-transform infrared (FT-IR) spectroscopy, Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). It was possible to verify the functional features of the synthesized MIP related to the extraction process of the template molecule. The CPE modified with MIP for sesquiterpene β-caryophyllene recognition was characterized by electrochemical techniques as cyclic voltammetry (CV) and square wave voltammetry (SWV). The highest selective recognition electrode enables to detect concentrations in the range between 1.5 × 10^-7 and 7.5 × 10^-7 M, showing great potential for applications in monitoring content of sesquiterpene β-caryophyllene in technological processes and for predicting the quality of extracts, oils, and resins of plants.