Search

[Display omitted] • Apigenin nanoparticles were prepared by antisolvent crystallization technology. • Antisolvent technology optimization models were obtained using RSM design. • The crystal form of apigenin transforms into an amorphous form after the SEDS process. • The bioactivity of apigenin was improved. Flavonoids have many positive pharmacological properties, such as antioxidant, antitumor, and anti-inflammatory activities. However, factors such as low water solubility and low dissolution rate limit their use. To overcome their poor solubility, carrier-free apigenin (API) microparticles and nanoparticles were prepared using three types of antisolvent precipitation technologies: supercritical antisolvent (SCF) technology, ultrasonic-assisted liquid antisolvent (UAL) technology, and high-pressure homogenization (HPH) technology. All three technologies can produce uniform tiny particles. However, the API particles obtained using these different techniques show subtle differences in terms of physical and chemical properties and biological activity. The preparation, characterization, and potential use of API microparticles and nanoparticles to improve in vitro release were studied. The resulting API particles were investigated and compared using Fourier-transform infrared spectroscopy, differential scanning calorimetry, X-ray powder diffraction, and scanning electron microscopy. We determined the optimum conditions for SCF, UAL, and HPH technologies to produce API microparticles and nanoparticles. The antioxidant and antitumor properties of the API particles were also investigated. The results demonstrated that the reduced particle size of the APIs prepared via SCF, UAL, and HPH technologies contributed to the enhanced dissolution rate, which in turn enhanced API bioactivity. [ABSTRACT FROM AUTHOR]

Baicalein, a bioactive flavonoid, exhibits various pharmacological activities and other beneficial effects, but its poor solubility and dissolution rate restrict its oral intestinal absorption rate and bioavailability. In this study, micronized baicalein was prepared by utilizing the technique of solution-enhanced dispersion by supercritical fluids (SEDS). Preparation, characterization, and the potential use of microparticles to improve the in vitro release of baicalein were studied. In vitro characterization data were obtained through Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), X-ray powder diffractometry (XRD), and scanning electron microscopy (SEM). The in vitro dissolution of the prepared microparticles was investigated and compared with raw powder. The results demonstrated that the prepared baicalein microparticles appeared as small flake shapes with a mean particle size (PS) of 0.614 μm under the appropriate conditions (solvent mixture of DCM and DMSO (5/1, v/v), drug concentration = 7 mg/mL, pressure = 16 MPa, and temperature = 308 K) without an observed change in the crystal form. Additionally, the reduced PS of baicalein microparticles contributed to the enhanced dissolution rate. [ABSTRACT FROM AUTHOR]

• Myricetin complex microparticles were successfully prepared by SAS technology. • SEM, DSC, FTIR and XRD were used to characterize the properties of myricetin. • The influences of process conditions were investigated. • Solubility, dissolution rate and pharmaceutical activity were improved. [Display omitted] Myricetin (MYR) shows a lot of pharmacological activity such as antioxidant capacity and antitumor activity. However, the poor aqueous solubility of MYR (2 μg/mL) limits its pharmaceutical applications. To improve the dissolution rate of MYR, microparticles and inclusion complexes of MYR were successfully prepared by supercritical antisolvent (SAS) technology. The effects of the drug concentration, temperature, pressure, CO 2 and solution volumetric feeding rate on the formation of MYR microparticles and the MYR/hydroxypropyl-β-cyclodextrin (HP-β-CD) complex microparticles were investigated systematically. The physical and chemical properties of the MYR microparticles were characterized by SEM, DSC, FTIR and XRD. After SAS processed, the particle size of MYR microparticles decreased and the crystal form of MYR changed due to the complexation with HP-β-CD, which lead to enhanced solubility, dissolution rate and further improve the antioxidant activity and antitumor activity. [ABSTRACT FROM AUTHOR]

Polysaccharides from fungi are good free radical scavengers. However, there are no enzymes digesting these polysaccharides in the human body, which limits the use of fungal polysaccharides. Therefore, it is of great significance to study the preparation methods of fungal polysaccharides to improve the utilization rate of fungal polysaccharides. In this paper, the acidic polysaccharide of Tremella fuciformis was extracted by boiling and precipitated by ethanol. The total sugar content obtained by freeze-drying after ion exchange chromatography purification was 93.6%. It is mainly composed of mannose, glucuronic acid, xylose and fucose. According to the peak area, the mass ratio of the substance is about 6.8:1:1.5:0.6, which indicates that TFP is a polysaccharide with mannose as its main chain and glucuronic acid, fucose and xylose as well as a small amount of glucose as the branch chain. Molecular weight is 1.86 × 106 Da. The existence of glucuronic acid endows polysaccharides with negative charge in aqueous solution and can be assembled into nanostructures with chitosan. By measuring the swelling property in aqueous, it shows the TFP separated from Tremella fuciformis fruits is suitable for drug controlled release. • The polysaccharide extracted from Tremella Fuciformis Fruiting body, and characterized by HPLC, FTIR, HPGPC, 1H NMR/13C NMR. • Methods of nanostructures assembly of Tremella Fuciformis polysaccharide with chitosan were reported. • The nanostructures were characterized by FTIR, SEM and DLS. • The properties of medicine encapsulation and heavy metal ions absorption of the nanostructures were investigated [ABSTRACT FROM AUTHOR]

Human embryonic stem cells (hESCs) are highly fragile with massive cell death after dissociation into single cells, which seriously hampers their applications. The mechanism underlying the massive cell death after dissociation still remains elusive. Here, the expression of apoptosis-related proteins, cell survival and mitochondrial membrane potential in dissociated hESCs before and after the treatments with a protein kinase A (PKA) inhibitor H89 and p53 inhibitor Pifithrin α were investigated, respectively. Protein interactions were identified by immunoprecipitation and immunofluorescence. The results show that the dissociation causes Caspase-dependent apoptosis in hESCs mediated by mitochondrial pathway with the up-regulation of pro-apoptotic proteins, decrease in mitochondrial membrane potential and elevation in pro-apoptotic Cyto c release, which are obviously suppresses by H89. The dissociation-induced increase of phosphorylated p53 Ser15 (p-p53) is suppressed by Pifithrin α which also rescues the elevated levels of pro-apoptotic proteins in mitochondrial pathway. During the dissociation-induced apoptosis, PKA/p-p53/Bax signaling pathway is identified by immunoprecipitation and immunofluorescence showing the most likely interaction between them. These results indicate that dissociation induces mitochondrial apoptosis in hESCs involving PKA/p-p53/Bax signaling pathway, which not only give new insights into the apoptosis mechanism of dissociated hESCs, but also provide clues for developing potential strategies to promote hESC survival after dissociation. [ABSTRACT FROM AUTHOR]

• Hesperetin nanoparticles were prepared using SAS method for the first time. • Supercritical CO 2 was used as an antisolvent and a pore-causing agent. • Physicochemical property of hesperetin nanoparticles were systematically investigated. • Solubility and dissolution rate was significantly improved. • Bioactivity of processed hesperetin was improved. Hesperetin (HST) is a bioflavonoid from citrus fruits and its clinical application is still markedly limited by its poor water solubility (1.27 µg/mL). Herein, a complex nanoparticle containing HST and hydroxypropyl-β-cyclodextrin (HP-β-CD) was prepared through supercritical antisolvent (SAS) technology to improve HST solubility, dissolution rate and bioactivity. The effects of crystallization temperature, crystallization pressure, mass flow rate, and drug concentration were systematically investigated using single-factor experiment and orthogonal experiment. The physicochemical properties and structure of the complex were examined using SEM, FTIR, DSC, BET, XPS and XRD analyses. After processing through SAS technology, the in vitro performance of HST was significantly improved such as solubility, dissolution rate and antineoplastic activity. HST as a potential antiproliferative and antioxidant compound appear to have anti-tumor effect on A549 cells. The above results proved that supercritical antisolvents crystallization was a feasible method to fabricate polymer-pharmaceutical complex nanoparticles for drug delivery system. [Display omitted] [ABSTRACT FROM AUTHOR]

The influence of different parts of corn stover on lignin extraction was investigated. Five kinds of lignin were isolated by the high boiling point solvent extraction from the whole corn stover and four different parts including leaf, husk, bark and pith. The optimal condition was obtained: 6.25 g/L NaOH, 140 °C, 1 h and 60% (v/v) 1,4-butanediol. The extracted lignins were then characterized. FT-IR analysis revealed that all of the lignins were typically herbaceous. The lignin extracted from husk contained more S unit. Gel permeation chromatography analysis showed that it was necessary to separate corn stover into different parts to obtain low polydispersity lignin. The SEM and FT-IR analysis proved that the lignin dissolution was related to the tightness structure presenting a positive correlation with hydrogen bond index. [ABSTRACT FROM AUTHOR]

The poor aqueous solubility of indapamide (INP) limits its applicability in various biomedical applications. To overcome this issue, nanosized INP particles (INP-HP-β-CD NPs and INP-PVP-K30 NPs) were fabricated using the supercritical antisolvent (SAS) approach to improve the bioavailability of INP. The process, formula, and supercritical antisolvent process were optimized using single-factor and orthogonal methods. The tiny INP-HP-β-CD NPs with a particle size of 142.5 nm and INP-PVP-K30 NPs with a particle size of 150.4 nm were obtained under optimum conditions. Further analysis and characterization, such as SEM, FTIR, XRD, DSC, 1H NMR, and dissipative particle dynamics (DPD) simulations, were carried out to verify the formation mechanism of the INP complex nanoparticles. The altered physical state of INP from crystalline to amorphous loaded onto the polymer resulted in a significant improvement in the solubility and dissolution rate and high biocompatibility with cells compared to raw INP. Therefore, we propose that INP nanoparticles processed by a supercritical antisolvent process can be used as an advanced drug delivery system, especially for insoluble drugs. [Display omitted] • Indapamide nanoparticles with narrow size distribution were produced by SAS process. • Solubility of INP-HP-β-CD NPs and INP-PVP-K30 NPs was significantly improved compared to raw drug. • Dissolution rate of INP was significantly enhanced after nanonization. • DPD simulation was employed to analyze formation process of indapamide nanoparticles. [ABSTRACT FROM AUTHOR]

The lack of handy and reliable sensing strategy for non-contact freshness assessment is a problem faced by food industries. This work presented an innovative solution for freshness monitoring of proteinous foods: halochromy- and fluorescence-based dual-response sensors with rapid and irreversible readout. Sensors were prepared by the polycondensation of CdTe quantum dots (QDs)-doped silane coupling agents onto filter papers and then anchoring of pH-sensitive halochromic compounds like blueberry anthocyanin (BA) by electrostatic interaction. The as-designed sensors showed rapid (within 1 min) responsiveness on both appearance and fluorescence toward total volatile basic nitrogen (TVB-N) through pH-sensitive structural variations of BA and inner filter effect (IFE)-induced fluorescence quenching of QDs, giving a LOD as low as 0.01 ppm (ammonia) within working range of 0.001–50 ppm, and such a dual-signal response could be sustained at least for 7 days after removal of TVB-N. As a proof-of-concept, dual-response spoilage sensing of proteinous foods was experimentally proved to be highly feasible and reliable using pork, shrimps and shelled eggs as representatives of real food samples. Smartphone-based digital color information of paper sensors before and after sensing was furtherly applied to reconstruct digitized binary response, reinforcing the credibility of this strategy. • A dual-response sensing strategy has been initiated for foods spoilage assessment. • Fluorescence sensing was realized by IFE-induced fluorescence quenching. • Rapid and irreversible readout of paper sensors ensured their high accuracy. • Cross verification of dual sensing modes reinforced methodological credibility. • This work offered a guideline for design of sensors with improved reliability. [ABSTRACT FROM AUTHOR]

In this work, a multiplexed colorimetric strategy was initiated for simultaneous and fast visualization of dyes using low-cost and easy-to-prepare indicator papers as sorbents. Response surface methodology (RSM) was employed to model statistically and optimize the process variables for dyes extraction and colorimetric assays. Multiplexed colorimetry was realized by virtue of synchronous color alignments from different dimensions of multiple dyes co-stained colorimetric cards under RSM-optimized conditions, and smartphone-based image analysis was subsequently performed from different modes to double-check the credibility of colorimetric assays. As concept-to-proof trials, simultaneous visualization of dyes in both beverages and simulated dye effluents was experimentally proved with results highly matched to HPLC or spiked amounts at RSM-predicted staining time as short as 50 s ∼3 min, giving LODs as low as 0.97 ± 0.22/0.18 ± 0.08 μg/mL (tartrazine/brilliant blue) for multiplexed colorimetry, which much lower than those obtained by single colorimetry. Since this is the first case to propose such a RSM-guided multiplexed colorimetric concept, it will provide a reference for engineering of other all-in-one devices which can realize synchronous visualization applications within limited experimental steps. [Display omitted] • A multiplexed colorimetry has been initiated for simultaneous visualization of dyes. • Colorimetric conditions were finalized by RSM within limited experimental runs. • Simultaneous colorimetric assays of different dyes could be achieved within 1 min. • Colorimetric sensitivity could be improved by multiplexed colorimetric strategy. • Smartphone-based image analysis was practical for assuring colorimetric results. [ABSTRACT FROM AUTHOR]

Actively tumor-targeted photothermal therapy (PTT) has been regarded as an attractive strategy for tumor treatment. Unfortunately, invasive damage caused by hyperthermia, irrepressible heating transfer and self-heating from in-organism water is always a real 'hot potato' in existing PTT modes. Herein, molecularly imprinted upconversion nanoparticles (UCPs@MIPs) were innovatively reported as an artificial antibody for active tumor targeting and microinvasive PTT. UCPs@MIPs were prepared using boronic acid-functionalized upconversion nanoparticles as a substrate, in-water polymerizable dopamine and m-aminophenylboronic acid as a functional co-monomer and photothermal couplant, and sialic acid, a monosaccharide overexpressed on most cancer cells, as a template to create tumor-targeted imprinting cavities. Uniquely, the as-designed UCPs@MIPs were of three-in-one traits, i.e., active tumor targetability, bright upconversion luminescence and superb photothermal properties, enabling to achieve tumor-targeted microinvasive PTT by virtue of semi-accurate hyperthermia tumor ablation while protecting the normal tissue from overheating. Finally, as a proof of concept, such a molecular imprinting technique (MIT)-based PTT mode was successfully applied to real biosystems using HepG2 tumor-bearing mice as tumor models. Since MIT has good versatility in the selection of imprinting methods, substrate materials and template molecules, it will find its wider applications in the fields of biosensing and nanomedicine. [ABSTRACT FROM AUTHOR]

Herein, a multi-mode visualization platform was initiated for in-situ detection of food dyes (FDs) by combining colorimetry, fluorometry and smartphone‑based digital image analysis, in which water-dispersible quantum dots (QDs) were served as nanoprobes. Colorimetry was achieved by color comparison, while both fluorometry and fluorescence quantification were performed through inner filter effect (IFE)-induced fluorescence quenching, then color information (RGB & gray-scale values) of colorimetry and fluorometry was picked by a smartphone to reconstruct digitized alignments. Since IFE mechanism was concentration-dependent but did not rely on the interaction between fluorophore and quencher, the whole process of fluorescence response could be finished within 10 s, and both color gradients and fluorescence changes showed fine mappings to FDs concentrations in the range of 1.0 × 10−3∼0.035 mg/mL for brilliant blue, and 1.0 × 10−4∼0.1 mg/mL for Allura red and sunset yellow. As a proof-of-concept, the in-situ multi-mode visualization of these FDs in real beverages was experimentally proved to be highly feasible and reliable as compared with instrumental techniques like UV–vis/fluorescence spectrometry, along with HPLC. Finally, this strategy was extended to the multi-mode visualization of non-food dyes in three simulated wastewater samples with high credibility by contrast with the true additive amounts of model dyes. [ABSTRACT FROM AUTHOR]

• Betamethasone microparticles and polymer complex nanoparticles were prepared. • The processed drugs exhibited greater solubility and lower cytotoxicity. • Influencing factors of the particle forming process were investigated. • Characterization was performed by SEM, DSC, FTIR, and XRD. Poor solubility limits the pharmacological activities of betamethasone (BM), including its anti-inflammatory and anti-allergic effects. To improve the aqueous solubility and dissolution rate of BM, supercritical antisolvent (SAS) technology was used to prepare BM microparticles and BM–polyvinylpyrrolidone (PVP) solid dispersion nanoparticles. The effects of temperature, pressure, solution feeding rate, and drug concentration on particle formation were investigated using both single-factor and orthogonal experimental methods, and the optimal preparation process was screened. The physicochemical properties of the BM particles were characterized by scanning electron microscopy, differential scanning calorimetry, Fourier transform infrared spectroscopy, and X-ray diffraction. After the SAS process, the particle size was reduced significantly and the crystalline shape was altered, which considerably increased the solubility and dissolution rate of BM. Furthermore, the toxicity of BM to live cells was reduced because of the BM–PVP solid dispersions. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • A filter paper- and smartphone-based POCTs strategy has been proposed for food colorants (FCs) detection. • Indicator papers could be handily prepared by the one-step polycondensation of UPTES. • Indicator papers own superb stainability with low colorable concentration of FCs and wide applicable pH range. • The whole POCTs processes can be finished within 1 min. • Filter paper- and smartphone-based POCTs strategy is of high feasibility and reliability. Herein, a robust instrument-free point-of-care tests (POCTs) strategy was proposed for rapid naked-eye detection of artificial food colorants (AFCs) using filter paper as a sampling and response device. Indicator papers were prepared by one-step polycondensation of silane coupling agents onto glass microfiber filter papers, then colorimetric cards with fine color mappings to AFCs concentration gradients were handily fabricated by AFCs extraction with indicator papers via electrostatic interaction and hydrophobic effect. The lowest concentration for AFCs visual detection was as low as 10−6 M and the whole POCTs process could be finished within 1 min. Furtherly, color information (RGB and gray-scale values) of AFCs-stained indicator papers and colorimetric cards from smartphone APP was used to reconstruct digitized colorimetry and reinforce its validity by mitigating the possible errors from subjective judgement on colors. Finally, such a dual-mode POCTs strategy was experimentally proved to be highly reliable for rapid visual detection of three AFCs (brilliant blue, Allura red, and sunset yellow) in real drinks by contrast with several instrumental methods like spectrophotometry, HPLC and MS. Due to its fine portability, speediness, low cost and user-friendliness, this strategy paves a promising way for AFCs-related food safety control. [ABSTRACT FROM AUTHOR]

• An instrument-free strategy for semiquantitative naked-eye determination of food colorants (FCs) was developed. • Filter paper-based colorimetric analysis was applied to naked-eye detection of FCs. • FCs indicator papers could be facilely prepared via one-step polycondensation of silane coupling agents onto filter papers. • Visual colorimetric determination of FCs in real-world beverages was achieved with high reliability. A filter paper-based colorimetric strategy for instrument-independent visual detection of artificial food colorants (FCs) was developed in this study. Indicator papers were prepared via the one-step polycondensation of silane coupling agents onto glass microfiber filter papers, and colorimetric cards with a fine one-to-one correspondence between their colors and FCs concentrations were straightforward obtained by the extraction of FCs with indicator papers by virtue of electrostatic interaction and hydrophobic effect. Filter papers post-modified via such a simple way were proved to be of improved binding class selectivity and colorimetric sensitivity, allowing for in-situ colorimetric assay of FCs in an unprecedently wide range of applicable pH (1.0–12.0) with high reliability and fine versatility. Finally, the semiquantitative naked-eye determination of FCs (Allura red, brilliant blue and sunset yellow) in real-world drink samples was experimentally confirmed to be feasible by comparison with the findings of UV–vis absorption spectra, HPLC and mass spectra. [ABSTRACT FROM AUTHOR]

The existing strategies for the determination of synthetic food colorants (FCs) in manufactured foods are highly relied on specialized instruments and skilled personnel which are limited by the high technical threshold and instrumentation cost. Herein, highly branched pipette tips (PTs) were fabricated as a robust all-in-one device for high-performance extraction and visual detection of FCs via handy aspiration and dispensing procedures of pipette controller. The density of extraction groups and inner specific surface area of PTs greatly increased after facile physical coating and subsequent layer-by-layer branching reactions, and the maximum increment in binding capacity of PTs was exceeded 300 times at 8–10 iterations of branching layers, enabling the PTs to be colored just by short-time extraction of FCs and to achieve the instrument-independent visual detection of FCs by virtue of their outstanding PT-SPE performance. As a proof-of-concept, the in-situ PT-based solid phase extraction (PT-SPE) with high recoveries (from 91.73 ± 4.76% to 99.90 ± 4.14%) and semiquantitative naked-eye detection of FCs (Allura red and brilliant blue) in real beverages were experimentally demonstrated to be highly feasible by comparison with classical techniques like spectrophotometry, HPLC, and mass spectrometry. [Display omitted] • Highly-branched PT was pioneered as an all-in-one device for semiquantitative naked-eye detection of FCs. • The branching modification of PT was implemented in a layer-by-layer way with fine controllability. • The binding capacity of PT towards FCs enhanced over 300 times after 8~10 iterations of branching layers. • PT-based in-situ extraction and visual detection of FCs in real beverage samples were proved to be highly feasible. [ABSTRACT FROM AUTHOR]

In this work, non-traditional metal-free polynitrogen chain N8− deposited on a nitrogen-doped carbon nanotubes (PN-NCNT) catalyst was successfully synthesized by a facile cyclic voltammetry (CV) approach, which was further tested in an oxygen reduction reaction (ORR). The formation of PN on NCNT was confirmed by attenuated total reflectance–Fourier transform infrared spectroscopy (ATR-FTIR) and Raman spectroscopy. Partial positive charge of carbon within NCNT facilitated electron transfer and accordingly induced the formation of more PN species compared to CNT substrate as determined by temperature-programmed decomposition (TPD). Rotating disk electrode (RDE) measurements suggested that a higher current density was achieved over PN-NCNT than that on PN-CNT catalyst, which can be attributed to formation of the larger amount of N8− on NCNT. Kinetic study suggested a four-electron pathway mechanism over PN-NCNT. Moreover, it showed long stability and good methanol tolerance, which indicates its great potential application. This work provides insights on designing and synthesizing non-traditional metal-free catalysts for ORR in fuel cells. [ABSTRACT FROM AUTHOR]

• Irbesartan microparticles and its composite microparticles were prepared by the ASES process for the first time. • The physicochemical of Irbesatan and the its composites were investigated and compared. • The solubility and dissolution rate of Irbesatan microparticles were improved obviously. • ASES Irbesartan composite microparticles should be a candidate for drug delivery system. In this study, irbesartan (IST) microparticles, an IST /hydroxypropyl-β-cyclodextrin (HP-β-CD) inclusion complex, and an IST/polyvinylpyrrolidone (PVP) complex were prepared using a supercritical aerosol solvent extraction system (ASES). The goal was to improve the solubility and dissolution rate of IST, which is an angiotensin II receptor blocker and exhibits solubility-limited oral bioavailability in pharmacokinetics. It is noteworthy that these three drug delivery systems show a higher solubility and dissolution rate of IST compared with raw IST. Fourier-transform infrared spectroscopy, differential scanning calorimetry, X-ray diffraction, and scanning electron microscopy analyses were conducted to study the physicochemical properties of IST before and after ASES processing, and to confirm the formation of the IST complexes with HP-β-CD and PVP. This study provides valuable information for the potential clinical application of IST microparticles and IST composite particles synthesized using the ASES process. [ABSTRACT FROM AUTHOR]