Segregation of Dispersed Silica Nanoparticles in Microfluidic Water-in-Oil Droplets: A Kinetic Study.

Dispersed negatively charged silica nanoparticles segregate inside microfluidic water-in-oil (W/O) droplets that are coated with a positively charged lipid shell. We report a methodology for the quantitative analysis of this self-assembly process. By using real-time fluorescence microscopy and automated analysis of the recorded images, kinetic data are obtained that characterize the electrostatically-driven self-assembly. We demonstrate that the segregation rates can be controlled by the installment of functional moieties on the nanoparticle's surface, such as nucleic acid and protein molecules. We anticipate that our method enables the quantitative and systematic investigation of the segregation of (bio)functionalized nanoparticles in microfluidic droplets. This could lead to complex supramolecular architectures on the inner surface of micrometer-sized hollow spheres, which might be used, for example, as cell containers for applications in the life sciences.

Increased Expression of IL-23 and IL-17 in Serum of Patients with Neonatal Respiratory Distress Syndrome and its Clinical Significance.

BACKGROUND: The present study focused on the potential clinical significance of Th-17 cell related inflammatory cytokines in the occurrence and development of neonatal respiratory distress syndrome (NRDS). METHODS: We included 82 NRDS children and 82 healthy controls. NRDS children were divided into the mild and severe group based on the disease severity. The serum samples of the NRDS and non-NRDS children were collected, and the expression levels of IL-17, IL-22, and IL-23 were determined by ELISA method. Moreover, correlation between the levels of the cytokines and the disease severity were analyzed, and receiver operating characteristics curve (ROC) analysis was performed to determine the diagnostic value of the cytokines. Finally, correlation between the lung ultrasound score (LUS) of the NRDS patients and the levels of IL-17 and IL-23 were analyzed. RESULTS: IL-17 and IL-23 were dramatically increased in serum of the NRDS patients compared with the non-NRDS patients; moreover, IL-17 and IL-23 were significantly higher in the severe compared with the mild NRDS group, and the levels of both IL-17 and IL-23 were positively correlated with the disease severity. Furthermore, ROC analysis showed that both IL-17 and IL-23 can distinguish NRDS patient, especially the severe NRDS patients from the non-NRDS patients with high sensitivity and specificity; finally, the levels of IL-17 and IL-23 were positively correlated with the LUS in NRDS patients. CONCLUSIONS: IL-17 and IL-23 were up-regulated in NRDS and may serve as sensitive biomarkers for the diagnosis and treatment of the disease.

Biopebble Containers: DNA-Directed Surface Assembly of Mesoporous Silica Nanoparticles for Cell Studies.

The development of methods for colloidal self-assembly on solid surfaces is important for many applications in biomedical sciences. Toward this goal, described is a versatile class of mesoporous silica nanoparticles (MSN) that contain on their surface various types of DNA molecules to enable their self-assembly into micropatterned surface architectures useful for cell studies. Monodisperse dye-doped MSN are synthesized by biphase stratification and functionalized with an aptamer oligonucleotide that serves as gatekeeper for the triggered release of encapsulated molecular cargo, such as fluorescent dye rhodamine B or the anticancer drug doxorubicin. One or two additional types of oligonucleotides are installed on the MSN surface to enable DNA-directed immobilization on solid substrates bearing patterns of complementary capture oligonucleotides. It is demonstrated that this strategy can be used for efficient self-assembly of microstructured surface architectures, which not only promote the adhesion and guidance of cells but also are capable of affecting the fate of adhered cells through triggered release of their cargo. It is believed that this approach is useful for diverse applications in tissue engineering and nanobio sciences.

Targeted delivery of NO donor and ROS scavenger for synergistic treatment of rheumatoid arthritis.

Rheumatoid arthritis (RA) is characterized by high level of reactive oxygen species (ROS) and proinflammatory cytokines, which facilitate the activation of the inflammatory signaling such as NF-κB pathway and exacerbate the development of inflammation. Herein, we designed a nanodrug by encapsulating the NO donor S-nitrosoglutathione (GSNO) into an emulsion and coating the surface with a polydopamine (PDA) layer to yield GSNO@PDA, which simultaneously scavenged the extra ROS and suppressed NF-κB signaling for potent RA treatment. To enhance the cellular uptake and NO generation efficiency, dextran sulfate (DS) and Cu2+ were anchored on the surface of GSNO@PDA to obtain the final formulation GSNO@PDA@DS. Our results demonstrated that GSNO@PDA@DS were successfully prepared and the modification of DS effectively boosted the cellular uptake of GSNO@PDA@DS. Moreover, GSNO@PDA@DS lowered cellular ROS and elevated intracellular NO, resulting in a decrease of M1 phenotype, inhibition of NF-κB pathway and down-regulation of proinflammatory cytokine tumor necrosis factor-α (TNF-α). Further in vivo studies confirmed that GSNO@PDA@DS significantly relieved symptoms and bone erosion by regulating the microenvironment of RA, highlighting the potential of GSNO@PDA@DS for RA therapy through ROS scavenging and NO-mediated suppression of inflammatory signaling.

Correction: Antimicrobial peptide-modified silver nanoparticles for enhancing the antibacterial efficacy.

[This corrects the article DOI: 10.1039/D0RA05640E.].

Electron transfer-based antioxidant nanozymes: Emerging therapeutics for inflammatory diseases.

Inflammatory diseases are usually featured with relatively high level of reactive oxygen species (ROS). The excess ROS facilitate the polarization of microphages into proinflammatory M1 phenotype, and cause DNA damage, protein carbonylation, and lipid peroxidation, resulting in further deterioration of inflammatory diseases. Therefore, alleviating oxidative stress by ROS scavenging has been an effective strategy for reversing inflammation. Inspired by the natural antioxidant enzymes, electron transfer-based artificial antioxidant nanozymes have been emerging therapeutics for the treatment of inflammatory diseases. The present review starts with the basic knowledge of ROS and diseases, followed by summarizing the possible active centers for the preparation of antioxidant nanozymes. The strategies for the design of antioxidant nanozymes on the purpose of higher catalytic activity are provided, and the applications of the developed antioxidant nanozymes on the therapy of inflammatory diseases are discussed. A perspective is included for the design and applications of artificial antioxidant nanozymes in biomedicine as well.

[Preparation of porous boron nitride-doped polypyrrole-2,3,3-trimethylindole solid-phase microextraction coating for polycyclic aromatic hydrocarbon detection].

Most polycyclic aromatic hydrocarbons (PAHs), which are persistent organic pollutants, have strong carcinogenicity, teratogenicity, and mutagenicity, and pose serious threats to the ecological environment and human health. Owing to the complexity of the matrix and low PAH content of environmental samples, separating and enriching PAHs in environmental samples is necessary prior to their detection. Solid-phase microextraction (SPME) technology is commonly used to detect PAHs owing to its advantages of simple operation, online connection with other instruments, low solvent usage, and integrability of sampling separation, enrichment, and desorption. The extraction coating is the core of this technology, and the type and thickness of the coating are important factors affecting the sensitivity and accuracy of the analysis. Common commercial extraction coatings include polydimethylsiloxane and quartz fiber; however, these materials have a number of disadvantages, such as poor thermal stability and high cost. Several methods, including electrochemical, sol-gel, molecular imprinting, and other coating methods, have been developed to prepare SPME coatings. Electrochemical methods have attracted considerable attention because of their simplicity, short duration, and high coating stability. In the development of an electrochemical method, the selection of the conductive polymer is of particular importance. Polypyrroles (Ppy) are easily synthesized and have numerous advantages, such as good conductivity and stable chemical properties. Thus, their use as a substrate material for SPME coatings is beneficial for improving the overall stability of the coating. Copolymerization with other polymers can enhance the adsorption performance of such coatings via synergistic effects. When doped with inorganic materials with high thermal stability, the composite coating can exhibit high temperature resistance. In this study, a porous boron nitride-doped Ppy-2,3,3-trimethylindole (Ppy/P2,3,3-TMe@In/BN) composite was prepared as a new SPME copolymer coating to detect three PAHs: naphthalene (NAP), acenaphthene (ANY), and fluorene (FLU). Scanning electron microscopy, thermal stability analysis, Fourier transform infrared spectroscopy, and other techniques were used to characterize the Ppy/P2,3,3-TMe@In/BN composite coating. The results showed that the coating featured a large number of porous and wrinkled dendritic structures, which increased the specific surface area of the composite coating and enabled the extensive enrichment of the three PAHs. When the sample inlet temperature of the chromatograph is 320 ℃, the chromatographic baseline of the coating is basically stable. Compared with commercial coatings, the prepared coating had better thermal stability. The coating formed stable intermolecular forces with the three PAHs owing to its numerous carbon-carbon double bonds (C=C), hydrogen bonds, and other structures, thereby achieving excellent enrichment of the target analytes. Compared with Ppy, Ppy/PIn, Ppy/P2,3,3-TMe@In, Ppy/BN, and polydimethylsiloxane (PDMS) coatings, the prepared Ppy/P2,3,3-TMe@In/BN composite coating exhibited better extraction effects for the three PAHs. The Ppy/P2,3,3-TMe@In/BN composite coating was polymerized on the surface of a stainless-steel wire by cyclic voltammetry and combined with gas chromatography-hydrogen flame ionization detection (GC-FID) to optimize the conditions influencing the extraction and separation of the three PAHs, thereby establishing a highly sensitive analytical method for detecting NAP, ANY, and FLU. This method had low limits of detection (LODs) of 10.6-14.5 ng/L (S/N=3) and high stability. The SPME-GC-FID method was used to detect the three PAHs in two environmental water samples, and a small amount of ANY (1.39 µg/L) was detected in one water sample. Satisfactory recoveries (82.5%-113.9%) were obtained when both water samples were spiked with the three PAHs at three levels. The experimental results indicate that the established analytical method can detect the three PAHs in environmental water samples.

Stimulus-responsive and dual-target DNA nanodrugs for rheumatoid arthritis treatment.

Tumor necrosis factor receptor-1 (TNFR1) and DEK are closely associated with the development of rheumatoid arthritis (RA). Taking advantage of the high adenosine triphosphate (ATP) in RA microenvironment and the interactions of DNA aptamers with their targets, an ATP-responsive DNA nanodrug was constructed that simultaneously targets TNFR1 and DEK for RA therapy. To this end, DEK target aptamer DTA and TNFR1 target aptamer Apt1-67 were equipped with sticky ends to hybridize with ATP aptamer (AptATP) and fabricated DNA nanodrug DAT. Our results showed that DAT was successfully prepared with good stability. In the presence of ATP, DAT was disassembled, resulting in the release of DTA and Apt1-67. In vitro studies demonstrated that DAT was superior to the non-responsive DNA nanodrug TD-3A3T in terms of anti-inflammation activity and ATP was inevitable to maximize the anti-inflammation ability of DAT. The superior efficacy of DAT is attributed to the more potent inhibition of caspase-3 and NETs formation. In vivo results further confirmed the anti-RA efficacy of DAT, whereas the administration routes (intravenous injection and transdermal administration via microneedles) did not cause significant differences. Overall, the present study supplies an intelligent strategy for RA therapy and explores a promising administration route for future clinical medication of RA patients.

Dual-targeting inhibition of TNFR1 for alleviating rheumatoid arthritis by a novel composite nucleic acid nanodrug.

Selective suppression of tumor necrosis factor (TNF) α-TNF receptor 1 (TNFR1) signaling is a potent solution for rheumatoid arthritis (RA). Herein, novel composite nucleic acid nanodrugs that simultaneously restrain TNF α binding and TNFR1 multimerization were designed to reinforce inhibition of TNF α-TNFR1 signaling for RA therapy. Towards this end, a novel peptide Pep4-19 that suppresses TNFR1 clustering was extracted from TNFR1. The resulting peptide and a DNA aptamer Apt2-55, which inhibits TNF α binding, were integrally or separately anchored on DNA tetrahedron (TD) to obtain nanodrugs with different spatial distribution of Apt2-55 and Pep4-19 (TD-3A-3P and TD-3(A-P)). Our results showed that Pep4-19 enhanced the viability of inflammatory L929 cells. Both TD-3A-3P and TD-3(A-P) suppressed caspase 3, reduced cell apoptosis, and inhibited FLS-RA migration. Compared to TD-3(A-P), TD-3A-3P supplied sufficient flexibility for Apt2-55 and Pep4-19, and showed better anti-inflammation properties. Furthermore, TD-3A-3P significantly relieved symptoms in collagen-induced arthritis (CIA) mice, and the anti-RA efficacy through intravenous injection was comparable to transdermal administration via microneedles. Overall, the work provides an effective strategy for RA treatment by dual-targeting TNFR1, and demonstrates that microneedles are promising approach to drug administration in the treatment of RA.

Dual-Drug Loaded Separable Microneedles for Efficient Rheumatoid Arthritis Therapy.

Although the inhibitors of the interleukin-6 receptor (IL-6R) and tumor necrosis factor-α (TNF-α) have achieved a certain success in the clinical treatment of rheumatoid arthritis (RA), great effort should be made to overcome side effects and to improve patient compliance. The present research aimed to address these problems by the co-delivery of tocilizumab (TCZ)-an inhibitor of IL-6R-and an aptamer Apt1-67, which specifically inhibits TNF receptor 1 via separable microneedles (MN). MN were featured with a sustained release of TCZ from needle tips and a rapid release of Apt1-67 from needle bodies by using methacrylate groups grafted hyaluronic acid as the fillings of needle tips and polyvinyl alcohol/polyvinyl pyrrolidone as the fillings of needle bodies. Our results demonstrated that TCZ and Apt1-67 were distributed in MN as expected, and they could be released to the surroundings in the skin. In vivo studies revealed that combined medication via MN (TCZ/Apt1-67@MN) was superior to MN loaded with a single drug. Compared with subcutaneous injection, TCZ/Apt1-67@MN was of great advantage in inhibiting bone erosion and alleviating symptoms of CIA mice. This study not only provides a novel approach for combined medication with different release properties but also supplies a strategy for improving drug efficacy.