Narrow Polydispersity Index Research Articles

Neuroprotective effect of naringenin-loaded solid lipid nanoparticles against streptozocin-induced neurotoxicity through autophagy blockage.

Autophagy is a pivotal contributing factor to modulate the progression of neurodegenerative diseases. Although naringenin (Nar) has shown beneficial effects against neurodegenerative diseases, its poor solubility and bioavailability have limited its application. The present research aimed to design a nanostructured formulation of Nar to achieve an enhanced therapeutic effect. Herein, Nar-loaded solid lipid nanoparticles (Nar-SLNs) were prepared and characterized. Then, PC12 cells were exposed to streptozocin (STZ) and/or Nar and Nar-SLNs in vitro to clarify the protective effect of Nar and its nanoformulation against STZ-stimulated neurotoxicity. The empty SLNs and Nar-SLNs indicated a narrow polydispersity index value with a negative zeta potential. As determined by the scanning electron microscopy images, the nanoparticles had a spherical shape and were less than 20 nm in size. FTIR results demonstrated the interaction between Nar and SLNs and supported the presence of Nar in the nanoparticle. The nanoformulation revealed an initial burst release followed by a sustained release manner. Treatment of PC12 cells with STZ resulted in mitochondrial dysfunction and increased autophagic markers, including LC3-II, Beclin1, Akt, ATG genes, and accumulation of miR-21 and miR-22. Both Nar and Nar-SLNs pre-treatment improved cell survival and augmented mitochondrial membrane potential, accompanied by reduced autophagic markers expression. However, Nar-SLNs were more effective than free Nar. As a result, our findings suggested that SLNs effectively enhance the neuroprotective effect of Nar, and Nar-SLNs may be a promising candidate to suppress or prevent STZ-elicited neurotoxicity. PRACTICAL APPLICATIONS: According to the beneficial effect of Nar in the management of neurodegenerative diseases, we evaluated the protective effect of Nar and Nar-SLNs against STZ-stimulated neurotoxicity and analyzed the role of autophagy in STZ-stimulated neurotoxicity. Our results proposed that Nar-SLNs could be a promising option for neurological disorders prevention through autophagy suppression.

Biogenic polymer-encapsulated diosgenin nanoparticles: Biodistribution, pharmacokinetics, cellular internalization, and anticancer potential in breast cancer cells and tumor xenograft

Diosgenin (DGN) is a natural bioactive steroidal saponin from therapeutic herbs and it exhibits potential anticancer efficacy. Here, we report the preparation of poly lactide-co-glycolide (PLGA)-encapsulated diosgenin nanoparticles (PLGA-DGN NPs) and characterization of their physicochemical nature, and morphology as well as inspect their drug-loading capability, in vitro drug release, pharmacokinetics, bio-distribution, safety profile. The in vitro and in vivo antineoplastic activities of PLGA-DGN NPs were also examined against the MCF-7 breast cancer cell line and in the Ehrlich ascites carcinoma (EAC) tumor xenograft model, respectively. The results displayed an appropriate size (∼147 nm), spherical shape, and a narrow polydispersity index. The nanoparticles showed a high encapsulation efficacy (78%), loading capacity (8%), good colloidal stability, and an initial burst release at an acidic medium. The nanoparticles exhibited significant cytotoxic activity at their IC50 dose compared to diosgenin. PLGA-DGN NPs facilitated cellular internalization of DGN in human breast cancer MCF-7 cells and extended the blood circulation time showing an excellent pharmacokinetic profile. Bio-distribution study revealed that PLGA-DGN NPs could significantly enhance DGN accumulation in tumor tissue. The safety profile of the PLGA-DGN NPs was confirmed in histopathologic, hematologic, and immunologic parameters of Swiss albino mice. At the same time, an effective antiangiogenic, and antiproliferative potential of PLGA-DGN NPs were exhibited in mice tumor xenograft model by showing tumor regression and down-regulating CD31 and Ki-67 expression. Therefore, PLGA-DGN NPs could be utilized as a promising anticancer drug, opening up a new avenue for further research.

Development and Evaluation of Elaeagnus rhamnoides (L.) A. Nelson Oil-Loaded Nanostructured Lipid Carrier for Improved Skin Hydration

Sea buckthorn (SB) (Elaeagnus rhamnoides (L.) A. Nelson) is rich in flavonoids, phenolic compounds, anthocyanins, carotenoids, and phytosterol. Its phytochemicals exhibit various biological activities, such as antioxidant, immunomodulatory and anti-carcinogenic activities. SB also helps prevent the development of wrinkles and protects the skin’s surface from UV rays. The purpose of the present study was to develop and characterize an SB oil (SBO)-loaded nanostructured lipid carrier (NLC) for improved skin hydration. The response surface methodology (RSM) and central composite design (CCD) were employed to optimize the influencing factors (wax percentage, surfactant percentage, and PEG400 percentage in the surfactant) to achieve the desirable qualities in SBO-NLCs. The optimum (minimum) size of SBO-NLCs (105.26 nm) was obtained with a combination of 2.5% wax, 7.5% surfactant, and 30% PEG400 in the surfactant. A narrow polydispersity index (PDI; 0.16), relatively low zeta potential (ZP; −15.63 mV), and high entrapment efficiency (EE; 90.88%) were observed in this study. Reduced quadratic and reduced 2FI models were adapted to predict conditions to attain the optimum size and PDI of SBO-NLCs, respectively. ZP and EE were predicted with the help of a reduced cubic model. All of the predicted models were statistically significant. Differential scanning calorimetry results suggested that the SBO-NLCs had less crystallinity and therefore reduced the rate of drug expulsion from the inner core of the NLCs. A noticeable level of occlusion effect was observed in the SBO-NLCs. The SBO-NLCs showed a faster vitamin E (biomarker for the drug) release rate into the skin within 24 h, and the released vitamin E level after 48 h was significantly higher than that for the free SBO. Additionally, SBO-NLCs delivered vitamin E into the inner skin significantly (22.73 ± 1.67 µg/cm2 of skin). In conclusion, the SBO-NLC is a potential delivery system that can be used to prevent skin water loss and improve skin hydration. Further investigations, such as drug stability and safety evaluations, are required prior to commercialization for human use.

Novel luteolin@pro-phytomicelles: In vitro characterization and in vivo evaluation of protection against drug-induced hepatotoxicity

A novel nanoformulation with the small molecule phytochemical dipotassium glycyrrhizinate as a nanomaterial was developed for the oral delivery of luteolin (Lut), a widely used phytochemical, but it suffered from poor water solubility and low oral bioavailability. This novel nanoformulation, named Lut@pro-phytomicelles, can be fabricated with a simple process. Lut@pro-phytomicelles can instantly dissolve into aqueous mediums and formulate through self-assembly a clear phytomicelle solution with a Lut encapsulation efficiency of 99.16 ± 0.90%, a small micelle size of 30.32 ± 0.12 nm, and a narrow polydispersity index of 0.138 ± 0.024. The optimized formulation demonstrated that Lut had solubility in up to 50 mg/ml of water as a result of its encapsulation within DG phytomicelles. Lut@pro-phytomicelles exhibited excellent characteristics, including good storage stability, a fast in vitro release profile, improvement in in vitro antioxidant activity, and high safety potential. In the oral bioavailability evaluation, a shorter Tmax, increased Cmax, and improved AUC0-t were obtained with Lut@pro-phytomicelles when compared to bare Lut. The distribution evaluation further showed that Lut@pro-phytomicelles could effectively increase the concentrations of Lut in all the tested organs and gastrointestinal segments. In the protection efficacy evaluation, 100 mg/kg Lut@pro-phytomicelles demonstrated strong effects against acetaminophen-induced hepatotoxicity. The mechanisms of inhibiting high-mobility group box 1 signaling and suppressing oxidative stress were involved in this strong treatment effect. These results showed that simple but novel Lut@pro-phytomicelles provided a new, promising nano-delivery system for Lut with a significantly improved in vivo profile.

Preparation of temperature‐sensitive fragrance nanocapsules and its controllable release property

AbstractTemperature‐sensitive nanocapsules with controllable release properties were synthesized through miniemulsion free radical polymerization method. Temperature‐sensitive N,N‐diethylacrylamide/N,N‐dimethylacrylamide (DEA/DMA) copolymer were systematically synthesized as shell materials, and the fragrance‐dementholized peppermint oil (DPO) was encapsulated as hydrophobic core material. The as prepared nanocapsules had high encapsulation efficiencies of more than 90% and small average diameters of less than 150 nm, as well as narrow polydispersity index (PDI) below 0.17. Furthermore, decreased DEA contents in shell material resulted in higher phase transition temperature and slower release rate of fragrance under the same temperature. By varying the copolymer composition of shell materials, the controllable release property of as prepared nanocapsules were also varied under different temperatures.

Effect of structural changes of lignin during the microwave-assisted alkaline/ethanol pretreatment on cotton stalk for an effective enzymatic hydrolysis

Effective delignification of lignocellulosic biomass is an important factor to improve the efficiency of enzymatic hydrolysis and ensure the economic feasibility of bio-refining. Cotton stalk (CS) was treated by a microwave-assisted alkaline/ethanol pretreatment (MAAP) (at 160 °C for 15 min) process to separate high-purity lignin and digestible cellulose-rich residue. Results showed that the MAAP process resulted in homogeneous lignin fractions with narrow polydispersity index (PI), and the isolated lignin fragments exhibited relatively smaller molecular weights and numerous phenolic OH groups than those in MWL. The crystallization index of cellulose-rich substrates was increased after the MAAP integrated process. Meanwhile, the glucose yield of the integrated residue reached the maximum (82.41%) after enzymatic hydrolysis. The utilization of MAAP process was a beneficial and promising scheme for the generation of lignin fractions with satisfactory purity and chemical reactivity, which will facilitate the value-added application of CS in the future biorefinery.

Daptomycin Cross-Linked Chitosan Nanoparticles Serve as an Antibacterial Drug Delivery System

This report was aimed to investigate smart chitosan-daptomycin nanoparticles (CTS-DAP NPs) prepared by a simple ionic gelation method and to document their bacteriostatic activity towards infections. The particle size of optimal CTS-DAP NPs was 146.3 ± 0.09 nm, with narrow polydispersity index and zeta potential of 24.87 ± 1.06 mV. The drug loading efficiency of CTS-DAP NPs was 60.8%, and their in vitro drug release behavior exhibited that DAP could be released sustainedly. Zone of inhibition (ZOI) test, which was used to determine the activity of CTS-DAP NPs against S. aureus, showed the inhibitory zone diameter increased from 11.7 to 15.06 mm along with increased DAP dose from 1.25 to 10 μg loaded in CTS-DAP NPs. Taken together, the CTS-DAP NPs may provide a reliable approach to inhibit bacterial infections.

Sorafenib-Loaded PLGA-TPGS Nanosystems Enhance Hepatocellular Carcinoma Therapy Through Reversing P-Glycoprotein-Mediated Multidrug Resistance.

Multidrug resistance (MDR) is a key determinant for hepatocellular carcinoma chemotherapy failure. P-glycoprotein is one of the main causes of MDR by causing drug efflux in tumor cells. In order to solve this thorny problem, we prepared a sorafenib-loaded polylactic acid-glycolic acid (PLGA) - D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) nanoparticles (SPTNs). SPTNs were successfully synthesized through an ultrasonic emulsion solvent evaporation method with a favourable encapsulation efficiency of 90.35%. SPTNs were almost spherical in shape with uniform particle size (215.70 ± 0.36 nm), narrow polydispersity index (0.27 ± 0.02) and negative surface charge (-26.01 ± 0.65 mV). In the cellular uptake assay, the intracellular coumarin-6 (C6) fluorescence of TPGS component-based PLGA nanoparticles (C6-PTNs) was 1.63-fold higher relative to that of PVA component-based PLGA nanoparticles (C6-PVNs). The half-maximal inhibitory concentration and apoptosis ratio of SPTNs against HepG2/MDR cells were 3.90 μM and 75.62%, respectively, which were notably higher than free SF and sorafenib-PLGA-PVA nanoparticles (SPVNs). The anti-drug efflux activities of SPTNs were assessed by the intracellular trafficking assay using verapamil as a P-gp inhibitor. SPTNs could effectively inhibit the drug efflux in tumor cells detected by flow cytometry, and suppressed relative MDR1 gene as well as P-glycoprotein expression in tumor cells. Attributed to the MDR reversion effect of SPTNs, the in vivo antitumor efficacy experiment showed that SPTNs significantly inhibited the tumor growth of HepG2/MDR xenograft-bearing nude mice, and obviously reduced the toxicity against liver and kidney compared with SF treatment. In summary, SPTNs, as highly efficient and safe antitumor nano delivery systems, showed promising potential for hepatocellular carcinoma therapy through reversing P-glycoprotein-mediated MDR. Graphical Abstract.

Thermally Stable Copolymers with Pendant “N-Arylimide” Groups Via Reversible Deactivation Radical Polymerization Technique

This paper reports the synthesis of copolymers of N-arylitaconimides (NAI) and methyl methacrylate (MMA) with random architecture via activator generated electron transfer atom transfer radical polymerization (AGET-ATRP) method, resulting in N-arylimide as pendant group.The AGET-ATRP is a versatile and famous reversible deactivation radical polymerization technique used to synthesize the well defined polymers. The structural characterizations of obtained copolymers were done using FT-IR, 1H-NMR spectroscopy and elemental analysis. The molecular weights of copolymers were in the range 8,000-20,000 g/ mol with a narrow polydispersity index i.e. 1.2-1.3. Thermal characterization of Poly(NAI-ran-MMA) copolymers were done using differential scanning calorimetry (DSC) and thermogravimetric analysis (TG/ DTG). DSC scans show 60-117% enhancements in the glass transition temperature (Tg), as compared to Poly(methyl methacrylate). The rate of copolymerization, molecular weight and Tg were observed to increase with increase in electron releasing nature of the substituent on aromatic ring of the pendant group.

Folic acid-modified curcumin-loaded liposomes for breast cancer therapy

Breast cancer is the commonest cancer among women, with more than 2 million cases per year and a lethality rate of 17.7%. The treatment of breast cancer still being a challenge due to the high heterogeneity of tumor cells. In this scenario, the development of targeted nanosystems for drug delivery has been investigated. Thus, the aim of this study was the development and characterization of folic acid-modified curcumin-loaded liposomes (LIP-CCM-FA) for the treatment of breast cancer. For this purpose, LIP-CCM-FA and unmodified liposomes (LIP-CCM) were developed and characterized in vitro using MCF-7 cells culture in two-dimensional (2D) and three-dimensional (3D) models. LIP-CCM and LIP-CCM-FA showed low particles size (~ 138 nm), narrow polydispersity indexes (~ 0.140), negative zeta potential (~ −13 mV), and high drug encapsulation efficiency (> 73%). Furthermore, LIP-CCM-FA showed a significantly greater cytotoxicity effect when compared with free curcumin and LIP-CCM using 2D and 3D cell culture models. In addition, in vitro cellular uptake assays using 2D and 3D models indicated higher cellular internalization and spheroid penetration of LIP-CCM-FA when compared with free curcumin and LIP-CCM, suggesting the potential of folic acid modification for improving drug internalization in breast cancer cells through its recognition by folate receptors overexpressed. In summary, this novel nanosystem demonstrated a greater in vitro antitumoral effect due to its ability to permeate tissues and be specifically recognized by folate receptors.

Unimolecule-based size-charge switchable nanomedicine for deep cancer sono-immunotherapy

Immune checkpoint inhibitor-based immunotherapy has been the most promising method for treating cancer patients. In this study, an anti-programmed death ligand 1 peptide inhibitor (APP) was engineered to act in the inner core of unimolecular polymers (Dex-PCR780-b-P(DPA-co-APP). The APP polymers had the capability of forming nano-micelles (PCR780-APP NMs) via self-assembly and featured controlled exposure in an acidic microenvironment while maintaining APP original bioactivity. Notably, in an acid tumor microenvironment, the PCR780-APP NMs (~ 121.1 nm, 2.3 mV) quickly switched into ultrasmall and positively charged PCR780-APP unimolecular micelles (PCR780-APP UMs; ~ 24.1 nm, 19.6 mV) with ultrastability, a narrow polydispersity index, and great fluorescence/photoacoustic (FL/PA) linearity due to its unique and definite unimolecular structure. Based on these advantages, under FL/PA imaging guidance, size-charge switchable PCR780-APP NMs could control exposure of APP and when combined with ultrasound, induce specific-dosage reactive oxygen species (ROS) that facilitates abundant immune T-cell recruitment and activation in deep solid tumors.

Co-assembly of foxtail millet prolamin-lecithin/alginate sodium in citric acid–potassium phosphate buffer for delivery of quercetin

Foxtail millet nanoparticles with smaller mean size at ∼130 nm and narrower polydispersity index at ∼0.05 were prepared in citric acid–potassium phosphate buffer (pH 8.0). Through lecithin (Lec)/sodium alginate (Alg) coating, a hydrophobic FP core, a Lec monolayer, and a hydrophilic Alg shell were formed spontaneously. Dissociation experiment revealed that electrostatic interaction and hydrogen bonding were main driving forces for the formation and maintenance of stable FP–Lec/Alg NPs. In addition, Lec/Alg coated NPs exerted an important role in sustaining the controlled release of the encapsulated quercetin under simulated gastrointestinal tract conditions. Cellular uptake test exhibited that FP-Lec-Alg NPs cold enter epithelial cells in a time-dependent manner, showing the maximum uptake efficiency were 22% and 24%, respectively, after 2 h of incubation. About 220 nm NPs can be recovered by adding 10% (w/v) sucrose. FP-Lec-Alg NPs were found to be promising delivery materials to deliver quercetin and improve its bioavailability.

Optimization and Evaluation of Ketoconazole Loaded Nanostructured Lipid Carriers Employing Microwave-Assisted Technique

The present research work is designed to formulate, optimize and evaluate the ketoconazole loaded nanostructured lipid carriers for the topical delivery. Ketoconazole loaded nanostructured lipid carriers were prepared by one pot single-step microwave assisted technique using Compritol® 888 ATO, Labrafac PG and soya lecithin employing 2-factors 3-level experimental design. The p-size of the optimized batch of microwave assisted ketoconazole loaded nanostructured lipid carriers was found to be 60.15 nm. The in vitro drug release in 24 h study showed the biphasic release pattern, initial burst release for 5 h followed by slower release upto 24 h. Furthermore, ex vivo skin permeation study revealed that 3670.99 μg/cm2 and 4644.78 μg/cm2 of drug permeated from ketoconazole loaded nanostructured lipid carriers hydrogel and marketed formulation with the flux rate of 305.91 μg/cm2/h and 387.06 μg/cm2/h, respectively at the end of 24 h. Confocal laser scanning microscope images demonstrated appreciable cell uptake of 5(6)-Carboxyfluorescein loaded nanostructured lipid carriers hydrogel compared to 5(6)-Carboxyfluorescein-loaded plain hydrogel. Optimized batch of nanostructured lipid carrier formulation produced by microwave assisted technique produced particles in nm range with narrow polydispersity index and high entrapment efficiency. X-ray study confirmed that the crystalline nature of ketoconazole changed to amorphous form in the process of nanostructured lipid carrier formulation and thermal behavior analyzed by differential scanning calorimetry confirmed inclusion of drug into lipid matrix in its amorphous form. After performing the optimization and evaluations of nanostructured lipid carriers it can be concluded that nanostructured lipid carriers bear the potential to be explored further for the topical and other pharmaceutical applications.

Synthesis of large and stable colloidal gold nanoparticles (AuNPs) by seeding-growth method

Colloidal gold nanoparticles (AuNPs) have been used in various applications, mainly in biomedical sciences for therapeutic and diagnostic purposes. These AuNPs can be conjugated with biomolecules and chemical substances due to their unique physical and chemical properties. The AuNPs are usually synthesized by a chemical method; namely Turkevich method or reduction method. However, this synthesis method is not suitable for synthesis of large AuNPs due to aggregation and instability of AuNPs suspension. Thus, the aim for this study is to evaluate the seeding-growth method for synthesis of large AuNPs. The seed of 15 nm AuNPs was initially produced using the citrate reduction method, then further grown to 40, 60, and 80 nm AuNPs using the mild reduction agent, hydroxylamine. Transmission electron microscopy (TEM), dynamic light scattering (DLS), and UV–vis- NIR spectroscopy were used to characterize the as-synthesized AuNPs. The narrow particle size distribution and low polydispersity index value (PDI) for all AuNPs revealed the presence of monodisperse AuNPs. The as-synthesized AuNPs are nearly spherical as shown by the degree of ellipticity (G) close to 1.00. This result showed no agglomeration of AuNPs in the colloidal suspension. The UV–vis-NIR spectra showed peaks shifted to a longer wavelength that confirmed increasing size of AuNPs. The synthesis of different sizes of AuNPs using the seeding-growth method was successful and stable with no aggregation and agglomeration.

A polymerizable Aggregation Induced Emission (AIE)-active dye with remarkable pH fluorescence switching based on benzothiazole and its application in biological imaging

In recent years, Aggregation Induced Emission (AIE)-active fluorescent materials have been attracting considerable attention because they play an important role in clinical medicine, photoelectricity, environmental science, biological imaging, and sensors. In this contribution, a novel tetraphenylethylene (TPE) derivative of 2-(4-(1,2,2-triphenylvinyl)benzene) benzothiazole methacrylate (TPBMA) monomer was synthesized by a Suzuki coupling and an acylation reaction using TPE and benzothiazole as structural units, whose maximum emission wavelength respectively appeared at 506 nm in neutral medium and 579 nm in acidic medium with excellent pH sensitivity, and it could change repeatedly at 500 nm and 579 nm under HCl/NH3 fuming, indicating the reversible fluorescence conversion property. As compared with the TPB dye, the emission wavelength of TPBMA spectra has an obvious red-shift, which is consistent with the transition energy level difference (△E) of highest occupied molecular orbital (HOMO) and lowest unoccupied orbital (LUMO) situation by quantum chemistry calculation. Subsequently, the copolymers PEG-TB were successfully prepared by RAFT polymerization of TPBMA and poly (ethylene glycol) monomethacrylate (PEGMA), and their molecular weight (Mw) was about 2.12 × 104 with a narrow polydispersity index (PDI). From the 1H NMR analysis, the actual fraction of TPBMA in the PEG-TB copolymers increased to 22.6% from 17.4% when the feed ratio of TBMTA changed to 25.0% from 20.0%. The obtained PEG-TB could self-assemble into fluorescent organic nanoparticles (FONs) with 100–150 nm diameter in aqueous solution, and their fluorescence intensity increased gradually with the increase of water fraction in the THF solution, indicating the obvious AIE behavior. Moreover, the as-prepared PEG-TB FONs exhibited the prospective potential in the field of biological imaging due to their low cytotoxicity, excellent biocompatibility and easy cells absorption.

Wild Passiflora (Passiflora spp.) seed oils and their nanoemulsions induce proliferation in HaCaT keratinocytes cells

Despite the potential of Passiflora spp. as potential as source of bioactive compounds, poor aqueous solubility and stability issues restrict their use in pharmaceutical field. The most suitable approach to overcome such limitations is the development of formulations based on proper delivery systems. Among them, nanoemulsions have been widely used as carrier systems that can guarantee better cutaneous performance of herbal oils. This study evaluated physicochemical properties and cellular effects of seed oils from four varieties of wild Passiflora spp. The fatty acids profile of the seed oils was analyzed by gas chromatography and cell viability assay was performed on J774 macrophages. The nanoemulsions were prepared for the different seeds oils and cell proliferation was evaluated on HaCaT keratinocytes. The oils presented a predominance of unsaturated fatty acids, mainly linoleic acid (>65%) and no cytotoxic effects were observed on J774 cells up to 100 μg/mL. All nanoemulsions presented droplet size about 200 nm, narrow polydispersity index (<0.300) and overall, physicochemical properties consistent with good stability after 90 days of storage. The oils and nanoemulsions induced proliferation of keratinocytes, where nanoemulsions prepared with P. alata oil was the most effective, reaching 150% effect. These findings demonstrate proper cytocompatibility of oils from wild Passiflora spp. and their ability to stimulate the proliferation of keratinocytes, which suggest their potential use as herbal bioactives for dermal healing. Their incorporation in nanoemulsions is an innovative approach for obtaining nanotechnological dermatological products through a sustainable concept that can reach organoleptic characteristics superior to the in natura product.

γ-Ray-Triggered Drug Release of Reactive Oxygen Species-Sensitive Nanomedicine for Enhanced Concurrent Chemoradiation Therapy.

Radiotherapy (RT) combined with chemotherapy remains a dominant therapeutic manner in clinical tumor treatment, which is irreplaceable in a short term. To seek an intrinsic connection of combined chemoradiation therapy and maximize the antitumor efficacy, we developed a reactive oxygen species (ROS)-sensitive nanomicelle drug delivery system based on a self-assembled amphiphilic polymer, hyaluronic acid-graft-poly-(propylene sulfide) (HA-PPS). A chemical radiosensitizer, doxorubicin (DOX), was encapsulated into the core of HA-PPS nanomicelles, constituting the DOX-loaded nanomicelles (HA-PPS@DOX NMs) with a spherical structure of around 205.10 ± 11.33 nm diameter with a narrow polydispersity index (PDI) of 0.135 ± 0.01. When combined with RT, the ROS-sensitive HA-PPS@DOX NMs disintegrated and released great drug cargos, which further enhanced cytotoxicity. Meanwhile, as a radiosensitizer, the released DOX sensitized cancer cells to radiotherapy, which has been confirmed by an enhanced sensitizer enhancement ratio (SER) value of 1.78 contributing to the increased cytotoxicity of concurrent chemoradiation tumor therapy, as evidenced by the improvement of half maximal inhibitory concentration (IC50 value) of DOX from 2.316 to 0.8235 μg/mL. Moreover, in vivo studies revealed that HA-PPS@DOX NMs exhibited prolonged circulation time and improved tumor accumulation. Particularly, the released DOX triggered by radiation strengthened radiotherapy sensitization in return. Consequently, these superiorities of HA-PPS@DOX NMs shown by the concurrent chemoradiation tumor therapy resulted in an ideal tumor inhibition rate of 70.4%, thus providing a promising ROS-sensitive nanomedicine for cancer treatment.

Synthesis of Poly(styrene sulfonyl chloride) via reversible addition-fragmentation chain transfer polymerization and characterization thereof for membrane applications

Reversible addition-fragmentation chain transfer (RAFT) polymerization has been examined for the synthesis of poly (styrene sulfonyl chloride) (PSSC) of high molecular weight and narrow polydispersity index (PDI). PSSC, contains reactive sulfonyl chloride that can allow use of organic solvent for membrane casting, and chemical modification through reactive sulfonyl groups. For PSSC preparation, end-capped styrene i.e. styrene sulfonyl chloride (SSC) is used as a monomer, which is derived from sodium 4-vinylbenzenesulfonate by chlorination with thionyl chloride. Fourier transform infrared spectroscopy, Raman spectroscopy and Proton nuclear magnetic resonance spectroscopy, have been successfully used to confirm the polymer architecture. End-group of PSSC containing RAFT agent (Cyanomethyl N-methyl-N-phenylcarbamodithioate), is also confirmed by fragmentation analysis using Gas chromatography-mass spectroscopy. Evaluation of PSSC by X-ray diffraction and differential scanning calorimetry showed that resulting polymer is predominantly amorphous in nature and has a glass transition temperature of 119 ​°C. Gel permeation chromatography data reveals formation of high molecular weight (84 ​kDa) PSSC with and low PDI (1.4). Moreover, PSSC can be converted to polyelectrolyte and can be crosslinked by interfacial polymerization concept; hence, it would have considerable prospective for membrane preparation for fuel cell and water purification.

Effective fractionation strategy of sugarcane bagasse lignin to fabricate quality lignin-based carbon nanofibers supercapacitors

Lignin is recommended to a tempting alternative precursor of petroleum for fabricating carbon nanofibers (CNFs) due to its high carbon content, low-cost and renewable resources. However, the property of lignin-based carbon nanofibers (LCNFs) is inferior owing to the heterogeneity and 3D-network structure of lignin, which hinders its application in supercapacitors. The latest developments in fractionation technology have shown great potential for overcoming the aforementioned shortcomings. However, most of fractionation methods mainly rely on expensive chemicals and complex reaction process, such as enzymes, multiple solvents, membranes, and dialysis tubes. Herein, we proposed a controllable and effective strategy to fractionate lignin by only changing the ratio of ethanol/water (V/V) as mixture solvent. This gradient extraction method effectively removed the part of lignin with small molecular and branching structure, thus selectively getting the fractionated lignin with high molecular weight, narrow polydispersity index, and good linear structure. Fortunately, when the ratio of ethanol/water was 6:4, the corresponding LCNFs (LCNFs-L60) was obtained with large specific surface area, independent filamentous morphology networks and excellent electrochemical property. Its specific capacitance was up to 405.8 F/g. This way features controllable and sustainable for preparing high-quality LCNFs supercapacitors.

Preparation and Characterization of α-Tocopherol-Loaded Nano-Lipid Carriers: Effect of Lipid Type and Carrier Oil Content

Nano lipid carriers for encapsulating α-tocopherol (α-TC) were successfully fabricated using hot homogenization method. The effect of oil content and type of lipid on the physicochemical properties of different formulations was investigated. The results showed that α-TC nanocarriers exhibited a small particle size (259.2-379 nm), narrow polydispersity index (PDI) (0.178-0.432) and high entrapment efficiency (EE) (95.73-99.22%). Nanostructured lipid carrier (NLC) of Compritol containing 45% corn oil (α-TC-NC45) was selected as the optimum formulation due to its smaller particle size and PDI and higher EE. The differential scanning calorimetry (DSC) and X-ray diffractometry (XRD) data revealed a low degree of crystalinity for α-TC-NC45 with two crystal forms of α and s´. Transmission electron microscopy (TEM) images also exhibited an almost spherical morphology for the particles. The α-TC-NC45 was found to be stable with respect to particle size, PDI and EE during a 3-month storage at both 4 and 25 °C. The results concluded that Nanostructured lipid carrier of Compritol containing 45% corn oil may be announced as an appropriate delivery system for food and beverages fortification with α-tocopherol