Purpose: The present study aims to address this issue by functionalizing GO with Pluronic F127 (PF) as a means to mitigate toxicity and resolve the biocompatibility of GO. Although results from previous studies generally indicated that Pluronic functionalized GO exhibits relatively low toxicity to living organisms, reports that emphasize on its toxicity, particularly during embryonic developmental stage, are still scarce.
Methods: In the present study, two different sizes of native GO samples, GO and NanoGO, as well as PF-functionalized GO, GO-PF and NanoGO-PF, were prepared and characterized using DLS, UV-Vis, Raman spectroscopy, FTIR, and FESEM analyses. Toxicological assessment of all GO samples (0-100 µg/mL) on zebrafish embryonic developmental stages (survival, hatching and heart rates, and morphological changes) was recorded daily for up to 96 hours post-fertilization (hpf).
Results: The toxicity effects of each GO sample were observed to be higher at increasing concentrations and upon prolonged exposure. NanoGO demonstrated lower toxicity effects compared to GO. GO-PF and NanoGO-PF were also found to have lower toxicity effects compared to native GO samples. GO-PF showed the lowest toxicity response on zebrafish embryo.
Conclusion: These findings highlight that toxicity is dependent on the concentration, size, and exposure period of GO. Functionalization of GO with PF through surface coating could potentially mitigate the toxicity effects of GO in embryonic developmental stages, but further investigation is warranted for broader future applications.
Objectives: The objective of this study was to utilize a chitosan-based nanoparticle system as the delivery carrier for glutamic acid, a model for encapsulated biomolecules to visualize the in vitro release and accumulation of the encapsulated glutamic acid from chitosan nanoparticle (CNP) systems.
Methods: CNP was synthesized via ionic gelation routes utilizing tripolyphosphate (TPP) as a cross-linker. In order to track glutamic acid release, the glutamic acid was fluorescently-labeled with fluorescein isothiocyanate prior encapsulation into CNP.
Results: Light Scattering data concluded the successful formation of small-sized and mono-dispersed CNP at a specific volume ratio of chitosan to TPP. Encapsulation of glutamic acid as a model cargo into CNP led to an increase in particle size to >100 nm. The synthesized CNP exhibited spherical shape under Electron Microscopy. The formation of CNP was reflected by the reduction in free amine groups of chitosan following ionic crosslinking reactions. The encapsulation of glutamic acid was further confirmed by Fourier Transform Infrared (FTIR) analysis. Cell viability assay showed 70% cell viability at the maximum concentration of 0.5 mg/mL CS and 0.7 mg/mL TPP used, indicating the low inherent toxicity property of this system. In vitro release study using fluorescently-tagged glutamic acids demonstrated the release and accumulation of the encapsulated glutamic acids at 6 hours post treatment. A significant accumulation was observed at 24 hours and 48 hours later. Flow cytometry data demonstrated a gradual increase in intracellular fluorescence signal from 30 minutes to 48 hours post treatment with fluorescently-labeled glutamic acids encapsulated CNP.
Conclusion: These results therefore suggested the potential of CNP system towards enhancing the intracellular delivery and release of the encapsulated glutamic acids. This CNP system thus may serves as a potential candidate vector capable to improve the therapeutic efficacy for drugs and biomolecules in medical as well as pharmaceutical applications through the enhanced intracellular release and accumulation of the encapsulated cargo.
METHODS: The mushroom was boiled in hot water to liberate the polysaccharides, the extract of which was then used directly for the reduction of graphene oxide. The abundance of polysaccharides present in the mushroom serves as a good reducing agent. The proposed strategy evades the use of harmful and expensive chemicals and avoids the typical tedious reaction methods.
RESULTS: More importantly, the mushroom extract can be easily separated from the product without generating any residual byproducts and can be reused at least three times with good conversion efficiency (75%). It was readily dispersible in water without the need of ultrasonication or any surfactants; whereas 5 minutes of ultrasonication with various solvents produced RGO which was stable for the tested period of 1 year. Based on electrochemical measurements, the followed method did not jeopardize RGO's electrical conductivity. Moreover, the obtained RGO was highly biocompatible to not only colon (HT-29) and brain (U87MG) cancer cells, but was also viable towards normal cells (MRC-5).
CONCLUSION: Besides being eco-friendly, this mushroom based approach is easily scalable and demonstrates remarkable RGO stability and biocompatibility, even without any form of functionalization.
METHODS: Characterization of the synthesized AuNPs was done by different techniques such as ultraviolet-visible spectrum absorption, X-ray diffraction, dynamic light scattering, Fourier transform infrared spectroscopy, transmission electron microscopy, and energy-dispersive X-ray analysis.
RESULTS: All the results showed the successful green synthesis of AuNPs from Sx, which induced apoptosis of C666-1 cell line (NPC cell line). There was a decline in both cell viability and colony formation in C666-1 cells upon treatment with Sx-AuNPs. The cell death was proved to be caused by autophagy and mitochondrial-dependent apoptotic pathway.
CONCLUSION: Thus, due to their anticancer potential, these nanoparticles coupled with Sx can be used for in vivo applications and clinical research in future.
METHODS: fDTP2 was prepared by mounting fWGA on DTX-loaded nanoparticles (DTP2) using the two-step carbodiimide method. Morphology of fDTP2 was examined using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Dynamic light scattering (DLS) study was carried out to determine the mean diameter, polydispersity index (PDI) and zeta potential of fDTP2. Cellular uptake efficiency was examined using fluorescence microplate reader. Biocompatibility and active internalization of fDTP2 were conducted on HT-29.
RESULTS: fDTP2 was found to exhibit a DTX loading efficiency of 19.3%. SEM and TEM tests revealed spherical nanoparticles. The in vitro DTX release test showed a cumulative release of 54.7%. From the DLS study, fDTP2 reported a 277.7 nm mean diameter with PDI below 0.35 and -1.0 mV zeta potential. HT-29 which was fDTP2-treated demonstrated lower viability than L929 with a half maximal inhibitory concentration (IC50) of 34.7 µg/mL. HT-29 (33.4%) internalized fDTP2 efficiently at 2 h incubation. The study on HT-29 active internalization of nanoparticles through fluorescence and confocal imaging indicated such.
CONCLUSION: In short, fDTP2 demonstrated promise as a colonic drug delivery DTX transporter.
Methods: In this work, we reported a colorimetric method for clinical detection of PSA using gold nanoparticles (AuNPs) as the reporters. The method is based on ascorbic acid (AA)-induced in situ formation of AuNPs and Cu2+-catalyzed oxidation of AA. Specifically, HAuCl4 can be reduced into AuNPs by AA; Cu2+ ion can catalyze the oxidation of AA by O2 to inhibit the formation of AuNPs. In the presence of the PSA-specific peptide (DAHSSKLQLAPP)-modified gold-coated magnetic microbeads (MMBs; denoted as DAHSSKLQLAPP-MMBs), complexation of Cu2+ by the MMBs through the DAH-Cu2+ interaction depressed the catalyzed oxidation of AA and thus allowed for the formation of red AuNPs. However, once the peptide immobilized on the MMB surface was cleaved by PSA, the DAHSSKLQ segment would be released. The resultant LAPP fragment remaining on the MMB surface could not sequestrate Cu2+ to depress its catalytic activity toward AA oxidation. Consequently, no or less AuNPs were generated.
Results: The linear range for PSA detection was found to be 0~0.8 ng/mL with a detection limit of 0.02 ng/mL. Because of the separation of cleavage step and measurement step, the interference of matrix components in biological samples was avoided.
Conclusion: The high extinction coefficient of AuNPs facilitates the colorimetric analysis of PSA in serum samples. This work is helpful for designing of other protease biosensors by matching specific peptide substrates.
PURPOSE: Due to the high percentage of affected pregnant women, it should be mandatory to evaluate glucose levels during pregnancy and there is a need for a continuous monitoring system.
METHODS: Herein, the investigators modified the interdigitated (di)electrodes (IDE) sensing surface to detect the glucose on covalently immobilized glucose oxidase (GOx) with the graphene. The characterization of graphene and gold nanoparticle (GNP) was performed by high-resolution microscopy.
RESULTS: Sensitivity was found to be 0.06 mg/mL and to enhance the detection, GOx was complexed with GNP. GNP-GOx was improved the sensitive detection twofold from 0.06 to 0.03 mg/mL, and it also displayed higher levels of current changes at all the concentrations of glucose that were tested. High-performance of the above IDE sensing system was attested by the specificity, reproducibility and higher sensitivity detections. Further, the linear regression analysis indicated the limit of detection to be between 0.02 and 0.03 mg/mL.
CONCLUSION: This study demonstrated the potential strategy with nanocomposite for diagnosing gestational diabetes mellitus.
Materials and Methods: This work was focused on diagnosing osteosarcoma (OS), a common bone cancer, on MXene-modified multiple junction triangles by dielectrode sensing. Survivin protein gene is highly correlated with OS, identified on this sensing surface. Capture DNA was immobilized on MXene by using 3-glycidoxypropyltrimethoxysilane as an amine linker and duplexed by the target DNA sequence.
Results: The limitation and sensitivity of detection were found as 1 fM with the acceptable regression co-efficient value (y=1.0037⨰ + 0.525; R2=0.978) and the current enhancement was noted when increasing the target DNA concentrations. Moreover, the control sequences of single- and triple-mismatched and noncomplementary to the target DNA sequences failed to hybridize on the capture DNA, confirming the specificity. In addition, different batches were prepared with capture probe immobilized sensing surfaces and proved the efficient reproducibility.
Conclusion: This microgap device with Mxene-modified multiple junction triangles dielectrode surface is beneficial to quantify the survivin gene at its lower level and diagnosing OS complication levels.