Effects of Sonication Processing on the Behavior of the Synthesis Human Serum Albumin-SPIONs Loaded PLGA Nanoparticles

This paper reports the most prominent contributions in the field of biodegradable polymeric nanoparticles from poly (lactic-co-glycolic acid) (PLGA) used as a protein/drug delivery. We use a combination of Human Serum Albumin (HSA)-superparamagnetic iron oxide nanoparticles (SPIONs) loaded PLGA nanoparticles. To obtain protein stabilization, the optimization of each step of synthesis nanoparticle is required. One of the most common problems in encapsulating protein to PLGA nanoparticles is the presence of several challenges as a problem of instability. We explained how the effect of the various sonication processing on the synthesis HSA-SPIONs loaded PLGA nanoparticles would be one of the crucial parameters for stability.

Study of Human Serum Albumin-SPIONs Loaded PLGA Nanoparticles for Protein Delivery

The Biodegradable nanoparticles from poly(lactic-co-glycolic acid) (PLGA) have been extensively investigated for sustained and targeted/localized delivery of different agents. Many parameters are required in the synthesis of a biodegradable polymeric nanoparticle. We report the synthesis of human serum albumin (HSA)-superparamagnetic iron oxide nanoparticles (SPIONs) loaded PLGA nanoparticles. All nanoparticles were characterized using a TEM image, UV-Vis spectroscopy measurements, Zeta Potential, and PPMS for magnetizations. This study described and investigated the interesting phenomenon in the synthesis development of HSA-SPIONs loaded PLGA nanoparticles. The result showed that the stability of HSA-SPIONs loaded PLGA nanoparticles for potential applications such as in protein delivery.

Spions Increase Biofilm Formation by <i>Pseudomonas aeruginosa</i>

Limited research has suggested iron oxide nanoparticles (FeNP) have an inhibitory effect against several different genera of bacteria: Staphylococcus, Bacillus and Pseudomonas spp. In this study we looked at the effect of three different sets of Fe3O4 nanoparticles (FeNPs) on the development of Pseudomonas aeruginosa PAO1 biofilms. Two of the tested NPs were SPIONs (Superparamagnetic Iron Oxide Nanoparticles). Exposure of cells to the SPIONs at concentrations up to 200 μg/ml resulted in an increase in biofilm biomass by 16 h under static conditions and a corresponding increase in cell density in the bulk liquid. In contrast, these biofilms had decreased levels of extracellular DNA (eDNA). Fe(II) levels in the supernatants of biofilms formed in the presence of FeNPs exceeded 100 μM compared with 20 μM in control media without cells. Spent cell supernatants had little effect on Fe(II) levels. Cells also had an effect on the aggregation behavior of these nanoparticles. SPIONs incubated with cells exhibited a decrease in the number and size of FeNP aggregates visible using light microscopy. SPIONs resuspended in fresh media or spent culture supernatants formed large aggregates visible in the light microscope upon exposure to a supermagnet;and could be pelleted magnetically in microtitre plate wells. In contrast, SPION FeNPs incubated with cells were unaffected by exposure to the supermagnet and could not be pelleted. The results of this study indicate a need to reconsider the effects of FeNPs on bacterial growth and biofilm formation and the effect the bacterial cells may have on the use and recovery of SPIONs.

Co-delivery of mRNA and SPIONs through amino-ester nanomaterials

Nanoparticles have been widely explored for combined therapeutic and diagnostic applications. For example, lipid-based nanoparticles have been used to encapsulate multiple types of agents and achieve multi-functions. Herein, we enabled a co-delivery of mRNA molecules and superparamagnetic iron oxide nanoparticles （SPIONs） by using an amino-ester lipid-like nanomaterial. An orthogonal experimental design was used to identify the optimal formulation. The optimal formulation, MPA-Ab-8 LLNs, not only showed high encapsulation of both mRNA and SPIONs, but also increased the r2 relaxivity of SPIONs by more than 1.5-fold in vitro. MPA-Ab-8 LLNs effectively delivered mRNA and SPIONs into cells, and consequently induced high protein expression as well as strong MRI contrast. Consistent herewith, we observed both mRNA-mediated protein expression and an evident negative contrast enhancement of MRI signal in mice. In conclusion, amino-ester nanomaterials demonstrate great potential as delivery vehicles for theranostic applications.

PEG/PEI/PASP修饰的磁性氧化铁纳米粒子的制备及磁共振成像的研究

以聚乙二醇(Polyethylene glycol,PEG)为溶剂及反应剂,聚乙烯亚胺(Polyethyleneimine,PEI)为添加剂,乙酰丙酮铁(Fe(acac) 3 )为铁源,采用高温热分解法制备了超顺磁性氧化铁纳米粒子(Super-paramagnetic iron oxide nanoparticles,SPIONs)。通过物理法将聚天冬氨酸(Poly aspartic acid,PASP)成功修饰在PEG、PEI修饰的超顺磁性氧化铁纳米粒子(PEG/PEI-SPIONs)表面,得到PEG/PEI/PASP-SPIONs。透射电子显微镜表征结果显示,PEG/PEI/PASP-SPIONs具有良好的分散性,且平均粒径为(10.8±2.0) nm(平均值±标准差)。小鼠脑部磁共振成像实验表明,PEG/PEI/PASP-SPIONs可以长时间在小鼠脑部呈现磁共振成像(MRI)效果,PEG/PEI/PASP-SPIONs在小鼠脑部的成像时间比PEG/PEI-SPIONs和PEG/PEI/Tween 80-SPIONs的成像时间更短,可用于磁共振成像的造影剂。

物理和化学法合成钙离子敏感MRI造影剂对比研究

以聚乙烯亚胺(PEI)为添加剂,在聚乙二醇(PEG)中高温热解乙酰丙酮铁(Fe(acac)3)合成超顺磁性氧化铁纳米粒子(PEI/PEG-SPIONs),再与钙离子螯合剂EGTA分别通过物理混合法和EDC/sulfo-NHS化学法合成了对钙离子敏感的磁共振成像(MRI)造影剂EGTA-SPIONs/P(物理混合)和EGTA-SPIONs/C(化学法)。PEI/PEGSPIONs、EGTA-SPIONs/P和EGTA-SPIONs/C分散于HEPES缓冲液中的电泳粒度分别为27.6±3.2 nm、32.1±5.2 nm和36.1±4.8 nm;加入Ca2+后EGTA-SPIONs/P和EGTA-SPIONs/C的平均电泳粒度均趋于变大,呈双峰分布,再加入EDTA后,平均电泳粒度又都趋于减小。MRI测试结果表明,当Ca2+浓度从0.8 mmol/L增加到1.2mmol/L时,EGTA-SPIONs/P和EGTA-SPIONs/C样品的T2值分别增加了33%和33.5%;将0.8 mmol/L EDTA加入混合0.8 mmol/L Ca2+的EGTA-SPIONs/P和EGTA-SPIONs/C的分散液中,其T2值分别降低了14%和42%。EGTA-SPIONs/P及EGTA-SPIONs/C对Ca2+浓度的增加均有反映,但Ca2+@EGTA-SPIONs/P的EDTA逆转效果不如Ca2+@EGTA-SPIONs/C的明显,化学法合成的EGTA-SPIONs/C更适合作为钙离子敏感剂。

Imaging and Therapeutic Applications of Optical and Thermal Response of SPION-Based Third Generation Plasmonic Nanodendrimers

In this study, 9 nm superparamagnetic iron oxide nanoparticles (SPION) were functionalized by polyamidoamine (PAMAM) dendrimer. Using tetracholoroauric acid (HAuCl4), magnetodendrimer (MD) samples were conjugated by gold nanoparticles (Au-NPs). Two different reducing agents, i.e. sodium borohydride and hydrazine sulfate, and pre-synthesized 10-nm Au-NP were used to evaluate the efficiency of conjugation method. The samples were characterized using X-ray diffractometry (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, UV-visible spectroscopy and fluorescence spectroscopy. The results confirmed that Au- NPs produced by sodium borohydrate and the pre-synthesized 10-nm Au-NPs were capped by MDs whereas the Au-NP prepared by hydrazine sulfate as a reducing agent was entrapped by MDs. Optical properties of the MDs were studied by laser-induced fluorescence spectroscopy (LIF) within a wide range of visible spectrum. Also, based on the thermal analysis, all synthesized nanostructures exhibited a temperature increase using 488 nm and 514 nm wavelengths of a tunable argon laser. The new iron oxide-dendrimer-Au NPs synthesized by sodium borohydrate (IDA- NaBH4) produced the highest temperature increase at 488 nm whereas the other nanostructures particularly pure Au-NPs produced more heating effect at 514 nm. These findings suggest the potential application of these nanocomposites in the field of bioimaging, targeted drug delivery and controlled hyperthermia.

Measurements of Pulsed 532 nm Laser Breakdown Spectroscopy of Synthesized Magnetite Nanoferrofluid

We describe the results of 532 nm pulse laser-induced breakdown spectroscopy (LIBS) of two samples of magnetite nanoparticles (SPIONs) nanoferrofluid synthesized at room (S1) and elevated temperatures (S2) and at three different laser energy levels and pulse frequency. The size of magnetite nanoparticles, size distribution, magnetic crystalline phase and magnetization were analyzed and measured using transmission electron microscopy (TEM), X-ray diffraction spectroscopy (XRD) and vibrating sample magnetometry (VSM). The SPIONs showed a distribution between 4 - 22 nm with a peak about 12 nm and saturation magnetization of about 65 emu/g. The Saha-Boltzmann analysis of spectra for medium energy level (1050 mJ) yields plasma temperatures of (3881 ± 200) K and (26,047 ± 200) K for Fe I and OV as the lowest and highest temperatures respectively. A range of corresponding electron density (Ne-) of (0.47 - 6.80) × 1020, (0.58 - 8.30) × 1020 and (0.69 - 9.96) × 1020 cm-3?were determined at 860, 1050 and 1260 mJ respectively using the estimated CCD pictures. The results confirmed a higher elements ratio for S1 than S2 and the signal intensity indicated a non-linear behaviour as a function of pulse frequency with the maximum ratio value at 3 Hz. At higher frequency of 6 Hz no such turning point was observed. The highest and lowest temperatures corresponded to Fe I and OV respectively. The LIBS technique can be utilized to study, characterize and determine the elements ratio required in most applications involving the synthesizing process.

Self-assembled multifunctional nanotheranostics against circulating tumor clusters in metastatic breast cancer

Circulating tumor clusters(CTC)disseminating from the primary tumor are responsible for secondary tumor formation where the conventional treatments such as chemotherapy and radiotherapy does not prevent the metastasis at locally advanced stage of breast cancer.In this study,a smart nanotheranostic system has been developed to track and eliminate the CTCs before it can colonize at a new site,which would reduce metastatic progression and increase the five-year survival rate of the breast cancer patients.Targeted multiresponsive(magnetic hyperthermia and pH)nanomicelles incorporated with NIR fluorescent superparamagnetic iron oxide nanoparticles were developed based on self-assembly for dual modal imaging and dual toxicity for spontaneous killing of CTCs in blood stream.A heterogenous tumor clusters model was developed to mimic the CTCs isolated from breast cancer patients.The nanotheranostic system was further evaluated for the targeting property,drug release kinetics,hyperthermia and cytotoxicity against developed CTC model in vitro.In vivo model in BALB/c mice equivalent to stageⅢandⅣhuman metastatic breast cancer was developed to evaluate the biodistribution and therapeutic efficacy of micellar nanotheranostic system.Reduced CTCs in blood stream and low distant organ metastasis after treatment with the nanotheranostic system demonstrates its potential to capture and kill the CTCs that minimize the secondary tumor formation at distant sites.

Influence of rare earth ion substitutions on the structural,optical,transport,dielectric,and magnetic properties of superparamagnetic iron oxide nanoparticles

Superparamgnetic Fe_3O_4 and RE:Fe_3O_4(RE=Dy,Nd,La)nanoparticles with an average crystallite size in the range of 15–24 nm,were synthesized by co-precipitation method.The samples were characterized using X-ray diffraction(XRD),scanning electron microscopy(SEM),vibrating sample magnetometer(VSM),UV–Vis spectroscopy,LCR bridge,and two-probe technique.X-ray diffraction patterns of all the investigated samples reveal the typical phase of magnetite structure,with a small contribution of orthoferrite(NdFeO_3)as a secondary phase in Nd:Fe_3O_4 sample.The saturation magnetization(M_s)of the samples has values in the range from 41.8 to 52.3 emu/g,and decreases with RE ion doping depending on the ionic radius.Negligible values of the coercivity H_c and remanenceM_r,indicate the superparamagnetic nature of the investigated samples.The calculated values of indirect optical band gap of Fe_3O_4 and RE:Fe_3O_4 nanoparticles are in the range of0.9–1.25 eV.The dielectric constant of the samples decreases,while their activation energy increases with the increasing of ionic radii of dopants.

Preparation of polydopamine based redox-sensitive magnetic nanoparticles for doxorubicin delivery and MRI detection

To improve the water-dispersity of superparamagnetic iron oxide nanoparticles(SPIONs),a novel polydopamine based redox-sensitive copolymer modified SPIONs were prepared for the biomedical application to deliver doxorubicin(DOX)and magnetic resonance imaging(MRI)detection.The major components of this nanoparticle include SPIONs and the redox-sensitive polydopamine(rPDA)crosslinked copolymer,where N,N-Bis(acryloyl)cystamine served as cross-linker,dopamine methacrylamide and a long-chain polyethylene glyco methyl ether methacrylate acted as comonomers.Here the rPDA@SPIONs were formed by the ligand exchange reaction of dopamine moiety with the oleic acid layer capped on the surface of SPIONs,and the inner area of the nanoparticles formed a reservoir for DOX,while the hydrophilic PEG moiety helped the nanoparticles well-dispersible in aqueous solution.The DOX-loaded rPDA@SPIONs demonstrated a high drug loading efficiency of 857μg DOX per mg iron,and a strong T2 relaxivity of 123 mM-1•S^(-1)for MRI.The drug release analysis of drug-loaded nanoparticles showed a sustained and high cumulative drug release in GSH up to 73%within 48 h,rather than the relatively low release rate of 37%in PBS(pH 7.4)without GSH.All the results showed that the designed magnetic nanoparticle may be a promising vehicle for anticancer drug delivery with stimuli-triggered drug release behavior,and also a foundation for building smart theranostic formulations for efficient detection through MRI.

Magnetic nanoparticles for environmental and biomedical applications： A review

Engineered magnetic nanoparticles （MNPs） hold great potential in environmental, biomedical, and clin- ical applications owing to their many unique properties. This contribution provides an overview of iron oxide MNPs used in environmental, biomedical, and clinical fields. The first part discusses the use of MNPs for environmental purposes, such as contaminant removal, remediation, and water treatment, with a focus on the use of zero-valent iron, magnetite （Fe304）, and maghemite （~,-Fe203） nanoparticles, either alone or incorporated onto membrane materials. The second part of this review elaborates on the use of MNPs in the biomedical and clinical fields with particular attention to the application of superparamag- netic iron oxide nanoparticles （SP1ONs）, which have gained research focus recently owing to their many desirable features such as biocompatibility, biodegradability, ease of synthesis and absence of hysteresis. The properties of MNPs and their ability to work at both cellular and molecular levels have allowed their application in vitro and in vivo including drug delivery, hyperthermia treatment, radio-therapeutics, gene delivery, and biotherapeutics. Physiochemical properties such as size, shape, and surface and magnetic properties as well as agglomeration of MNPs and methods to enhance their stability are also discussed.