Immobilization of Multivalent Titanium Cations on Magnetic Composite Microspheres for Highly Efficient DNA Extraction and Amplification.

Magnetic-assisted DNA testing technology has attracted much attention in genetics, clinical diagnostics, environmental microbiology, and molecular biology. However, achieving satisfying DNA adsorption and desorption efficiency in real samples is still a big challenge. In this paper, a new kind of high-quality magnetic composite microsphere of MM@PGMA-PA-Ti4+ was designed and prepared for DNA extraction and detection based on the strong interaction of Ti4+ and phosphate groups. By taking the advantages of high magnetic susceptibility and high Ti4+ content, the MM@PGMA-PA-Ti4+ microspheres possessed remarkable extraction capacity for mimic biological samples (salmon sperm specimens) with saturated loadings up to 533.0 mg/g. When the DNA feeding amount was 100 µg and the MM@PGMA-PA-Ti4+ dosage was 1 mg, the adsorption and desorption efficiencies were 80 and 90%, respectively. The kinetic and equilibrium extraction data were found to fit well with the pseudo-second-order model and Freundlich isotherm model. Furthermore, the MM@PGMA-PA-Ti4+ microspheres were successfully employed for DNA extraction from mouse epithelial-like fibroblasts. The extraction ability (84 ± 4 µg/mg) and DNA purity were superior to the comparative commercial spin kits, as evaluated by electrophoresis assays and qPCR analysis. The experimental results suggest that the MM@PGMA-PA-Ti4+ microspheres possess great potential as an adsorbent for DNA purification from complex biological samples.

Design and investigation of targeting agent orientation and density on nanoparticles for enhancing cellular uptake efficiency.

The design of targeting agent-conjugated systems is attracting much attention in cell targeted delivery and cancer therapy. However, quantitative study of the ligand density and binding efficiency is still limited due to the technical matters and tedious work involved. In this article, benzoboroxole-modified core-shell magnetic nanoparticles (MSP-AOPB NPs) as a drug carrier model were fabricated and transferrin (Tf) was immobilized on the nanoparticle surface in a site-oriented manner (Tf-MSP-AOPB NPs). The preparation conditions were investigated in detail to optimize the Tf binding efficiency. A suitable reaction temperature, time or initial feeding amount could significantly increase the Tf binding amount. The maximum Tf binding amount on the MSP-AOPB NPs was 184 mg g-1, and the targeting ligand density on the surface could be well controlled by simply adjusting the reaction conditions. In vitro studies demonstrated the excellent Tf-mediated targeting ability and enhanced cellular uptake efficacy by varying the ligand density. The optimal ligand binding amount for achieving the highest cellular uptake efficiency was 94 mg Tf/g, which corresponds to a ligand binding density of about 0.05 Tf/nm2, and the binding efficiency of conjugation was higher than 90%. Moreover, Tf-MSP-AOPB NPs prepared by a site-oriented conjugation strategy showed the best cell targeting ability, and their cellular uptake amount was 25 and 127 times higher than that of physical adsorption and EDC/NHS coupling reaction in HepG2 cells, respectively. This study provides a facile site-oriented bioconjugation technique for different kinds of antibodies, and a suitable ligand density can be easily attained to enhance the cellular uptake efficacy, which shows great significance for targeted delivery and cancer therapy.

Specific and Reversible Enrichment of Early-Stage Glycated Proteome Based on Thiazolidine Chemistry and Palladium-Mediated Cleavage.

Comprehensive analysis of protein glycation is important for better understanding of its formation mechanism and biological significance. The current preconcentration methods of glycated proteome mainly depend on the reversible combination of boronic acid and cis-dihydroxy group by pH adjustment, but it has inherent limitations (e.g., poor specificity and time-consuming). Herein, for the first time, a novel enrichment method for glycated peptides is proposed based on the reversible chemical reaction between aldehyde and 1,2-aminothiol groups, in which oxidized glycated peptides are captured onto the magnetic nanoparticles via thiazolidine chemistry and then released by palladium-mediated cleavage. The method is rapid, with excellent selectivity (even at a 1:1000 molar ratio of glycated peptides/nonglycated peptides) and high sensitivity (1 fmol/µL). As a good evidence, 1549 glycated peptides were identified from glycated human serum with 94.6% specificity, providing a powerful technique for high-throughput analysis of glycated peptides.

Magneto-sensitive photonic crystal ink for quick printing of smart devices with structural colors.

In this paper, we report a facile strategy to combine magneto-responsive photonic crystal (MRPC) ink with 3D printing technology. The building blocks of MRPC are based on Fe3O4 magnetic nanoparticle clusters (MNCs) with uniform and tunable size. The MNC dispersion is able to change its photonic band gap from red to blue as the external magnetic field strength is increased. The magneto-responsive photonic crystal ink can be readily obtained by taking advantage of an ethylene glycol (EG)-in-oil emulsion with a reinforced silicone rubber prepolymer as the outer phase. Using the well-designed formula, the MNC dispersion can be well-preserved inside the emulsion droplets of the ink, maintaining its original contactless magnetic field response. As a proof of concept, custom quick response code and butterfly patterns were successfully printed and showed vivid and tunable color as a function of the external magnetic field strength with good repeatability.

Entropy-Driven Quick Loading of Functional Proteins in Nanohydrogels for Highly Efficient Tumor Targeting Therapy.

With the gradual deep understanding of the tumorigenesis and development process, nanodrug are thought to have great prospects for individualized treatment of tumors. To deliver adequate concentration of active ingredients to targeted tissues, proteins are usually used as carriers to avoid clearance by the immune system. Herein, a new strategy is developed for preparation of the protein-functionalized targeting nanodrugs; different kinds of proteins (albumin, horseradish, transferrin, and ricin) can be quickly loaded in polyacrylic acid nanohydrogels (PAA-NGs) without discrimination within 1 min under the strong driving force of entropy; and the loading efficiency can reach 99% with about 50% loading content. Meanwhile, the activity of the released protein can be well retained. After oriented binding of the targeting agent on the surface of the nanocarriers by a unique and facile technique, the protein-loaded nanodrug exhibits excellent tumor cell uptake and targeting effect. The excellent targeting ability from the oriented binding is further proved by comparing with the non-oriented targeting system. With quick loading of the anti-tumor protein of ricin and oriented binding of transferrin protein (Tf), the targeting nanodrug (PAA-BB@Ricin/Tf) shows a remarkable anti-tumor effect. This study proves a new universal delivery and targeting strategy for improving the nanodelivery system, which has great potentials for clinical application.

MSCs-engineered biomimetic PMAA nanomedicines for multiple bioimaging-guided and photothermal-enhanced radiotherapy of NSCLC.

BACKGROUND: The recently developed biomimetic strategy is one of the mostly effective strategies for improving the theranostic efficacy of diverse nanomedicines, because nanoparticles coated with cell membranes can disguise as "self", evade the surveillance of the immune system, and accumulate to the tumor sites actively. RESULTS: Herein, we utilized mesenchymal stem cell memabranes (MSCs) to coat polymethacrylic acid (PMAA) nanoparticles loaded with Fe(III) and cypate-an derivative of indocyanine green to fabricate Cyp-PMAA-Fe@MSCs, which featured high stability, desirable tumor-accumulation and intriguing photothermal conversion efficiency both in vitro and in vivo for the treatment of lung cancer. After intravenous administration of Cyp-PMAA-Fe@MSCs and Cyp-PMAA-Fe@RBCs (RBCs, red blood cell membranes) separately into tumor-bearing mice, the fluorescence signal in the MSCs group was 21% stronger than that in the RBCs group at the tumor sites in an in vivo fluorescence imaging system. Correspondingly, the T1-weighted magnetic resonance imaging (MRI) signal at the tumor site decreased 30% after intravenous injection of Cyp-PMAA-Fe@MSCs. Importantly, the constructed Cyp-PMAA-Fe@MSCs exhibited strong photothermal hyperthermia effect both in vitro and in vivo when exposed to 808 nm laser irradiation, thus it could be used for photothermal therapy. Furthermore, tumors on mice treated with phototermal therapy and radiotherapy shrank 32% more than those treated with only radiotherapy. CONCLUSIONS: These results proved that Cyp-PMAA-Fe@MSCs could realize fluorescence/MRI bimodal imaging, while be used in phototermal-therapy-enhanced radiotherapy, providing desirable nanoplatforms for tumor diagnosis and precise treatment of non-small cell lung cancer.

Temperature profiles of calyceal irrigation fluids during flexible ureteroscopic Ho:YAG laser lithotripsy.

PURPOSE: To evaluate calyceal irrigation fluid temperature changes during flexible ureteroscopic Ho:YAG laser lithotripsy. METHODS: Between May 2019 and January 2020, patients with kidney stones undergoing flexible ureteroscopic Ho:YAG laser lithotripsy were enrolled. A K-type thermocouple was applied for intraoperative temperature measurement. Laser was activated at different power (1 J/20 Hz and 0.5 J/20 Hz) and irrigation (0 ml/min, 15 ml/min and 30 ml/min) settings, temperature-time curve was drawn and time needed to reach 43 °C without irrigation was documented. RESULTS: Thirty-two patients were enrolled in our study. The temperature-time curve revealed a quick temperature increase followed by a plateau. With 15 ml/min or 30 ml/min irrigation, 43 °C was not reached after 60 s laser activation at both 1 J/20 Hz and 0.5 J/20 Hz. At the power setting of 1 J/20 Hz and irrigation flow rate of 15 ml/min, the temperature rise was significantly higher than other groups. Without irrigation, the time needed to reach 43 °C at 1 J/20 Hz was significantly shorter than that at 0.5 J/20 Hz (8.84 ± 1.41 s vs. 13.71 ± 1.53 s). CONCLUSION: Ho:YAG laser lithotripsy can induce significant temperature rise in calyceal fluid. With sufficient irrigation, temperatures can be limited so that a toxic thermal dose is not reached, when irrigation is closed, the temperature increased sharply and reached 43 °C in a few seconds.

Robotic-assisted laparoscopic artery-sparing varicocelectomy using indocyanine green fluorescence angiography: Initial experience.

We reported our initial experience of robotic-assisted laparoscopic artery-sparing varicocelectomy using indocyanine green (ICG) fluorescence angiography in treatment of varicocele. A total of 45 varicocelectomies in 27 patients were performed. The mean operation time was 49.1 ± 8.5 min for unilateral and 65.6 ± 8.3 min for bilateral repair. 47.2 s after ICG injection, testicular artery (TA) was visualised. After an interval of 31.3 s, fluorescent veins were identified. Of all the 45 spermatic cords, 68.9% had a solitary artery, while 31.1% had 2 arteries. The mean hospital stay was 1.6 ± 0.9 days. Semen concentration and motility were significantly improved 6 months after surgery, no recurrence, hydrocele or testicular atrophy was observed. Our study demonstrated that robotic-assisted laparoscopic artery-sparing varicocelectomy using ICG fluorescence angiography is a safe, effective and promising technique in treatment of varicocele.

A facile method for the detection of DNA by using gold nanoparticle probes coupled with dynamic light scattering.

In this paper, we present a simple and rapid method for deoxyribonucleic acid (DNA) detection using gold nanoparticle probes coupled with dynamic light scattering (DLS) analysis. The redox agent 1,4-dithio-dl-threitol cross-links the gold nanoparticles (AuNPs) to form clusters, while the monothiol DNA could terminate the formation and stabilize the assembled clusters by their negatively charge-based repulsions. By varying the concentration of DNA, the different sizes of DNA-AuNP clusters can be obtained. The sizes of the DNA-AuNP clusters were determined by DLS. A linear correlation was obtained between the sizes and the logarithm of DNA concentration from 2 nM to 5 µM with a detection limit of 1 nM (S/N = 3).