A novel and economical approach for the synthesis of short rod-shaped mesoporous silica nanoparticles from coal fly ash waste by Bacillus circulans MTCC 6811.

Coal fly ash (CFA) is an industrial byproduct produced during the production of electricity in thermal power plants from the burning of pulverized coal. It is considered hazardous due to the presence of toxic heavy metals while it is also considered valuable due to the presence of value-added minerals like silicates, alumina, and iron oxides. Silica nanoparticles' demands and application have increased drastically in the last decade due to their mesoporous nature, high surface area to volume ratio, etc. Here in the present research work, short rod-shaped, mesoporous silica nanoparticles (MSN) have been synthesized from coal fly ash by using Bacillus circulans MTCC 6811 in two steps. Firstly, CFA was kept with the bacterial culture for bioleaching for 25 days in an incubator shaker at 120 rpm. Secondly, the dissolved silica in the medium was precipitated with the 4 M sodium hydroxide to obtain a short rod-shaped MSN. The purification of the synthesized silica particle was done by treating them with 1 M HCl at 120 °C, for 90 min. The synthesized short rod-shaped MSN were characterized by UV-vis spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Particle size analyzer (PSA), Field emission scanning electron microscopy (FESEM), and transmission electron microscope. The microscopic techniques revealed the short rod-shaped mesoporous silica nanoparticles (MSN) for the final nano-silica, whose size varies from 40 to 80 nm, with an average size of 36 ± 5 nm. The XRD shows the crystalline nature of the synthesized MSN having a crystallite size of 36 nm. The FTIR showed the three characteristic bands in the range of 400-1100 cm-1, indicating the purity of the sample. The energy dispersive X-ray (EDX) showed 53.04 wt% oxygen and 43.42% Si along with 3.54% carbon in the final MSN. The particle size analyzer revealed that the average particle size is 368.7 nm in radius and the polydispersity index (PDI) is 0.667. Such a novel and economical approach could be helpful in the synthesis of silica in high yield with high purity from coal fly ash and other similar waste.

Formulation and Evaluation of Pravastatin Sodium-Loaded PLGA Nanoparticles: In vitro-in vivo Studies Assessment.

Purpose: Pravastatin sodium (PVS) is a hypolipidemic drug which suffers from extensive first-pass metabolism and short half-life. Poly(d,l-lactide-co-glycolide) (PLGA) is considered a promising carrier to improve its hypolipidemic and hepatoprotective activities. Methods: PVS-loaded PLGA nanoparticles (PVS-PLGA-NPs) were prepared by double emulsion method using a full 32 factorial design. The in vitro release and the physical stability studies of the optimized PVS-PLGA-NPs (F5) were performed. Finally, both hypolipidemic and hepatoprotective activities of the optimized F5 NPs were studied and compared to PVS solution. Results: All the studied physical parameters of the prepared NPs were found in the accepted range. The particle size (PS) ranged from 90 ± 0.125 nm to 179.33 ± 4.509 nm, the poly dispersity index (PDI) ranged from 0.121 ± 0.018 to 0.158 ± 0.014. The optimized NPs (F5) have the highest entrapment efficiency (EE%) (51.7 ± 5%), reasonable PS (168.4 ± 2.506 nm) as well as reasonable zeta potential (ZP) (-28.3 ± 1.18mv). Solid-state characterization indicated that PVS is well entrapped into NPs. All NPs have distinct spherical shape with smooth surface. The prepared NPs showed a controlled release profile. F5 showed good stability at 4 ± 2°C during the whole storage period of 3 months. In vivo study and histopathological examination indicated that F5 NPs showed significant increase in PVS hypolipidemic as well as hepatoprotective activity compared to PVS solution. Conclusion: The PVS-PLGA-NPs could be considered a promising model to evade the first-pass effect and showed improvement in the hypolipidemic and hepatoprotective activities compared to PVS solution.

Homologous targeting nanoparticles for enhanced PDT against osteosarcoma HOS cells and the related molecular mechanisms.

BACKGROUND: No prominent advancements in osteosarcoma (OS) treatment have been made in the past 20 years. Although photodynamic therapy (PDT) is an emerging technique for cancer therapy, the lack of targeted photosensitizers for OS treatment severely limits its applications. RESULTS: In this study, we constructed a potential theranostic nanoplatform by using (poly (lactic-co-glycolic) acid (PLGA) nanoparticles (NPs) encapsulating IR780 into the shell (PLGA-IR780 NPs), which were further camouflaged with human OS cell membranes from the HOS cell line (MH-PLGA-IR780 NPs). These constructed NPs showed the capacity for homologous targeting with excellent photoacoustic (PA)/fluorescence (FL) imaging ability. Benefitting from their homologous targeting capacity, MH-PLGA-IR780 NPs obviously promoted cell endocytosis in vitro and tumor accumulation in vivo, which could further improve PDT performance under near-infrared (NIR) irradiation. In addition, to their homologous targeting and PA/FL dual-mode imaging ability, MH-PLGA-IR780 NPs had advantages in penetrating deeper into tumor tissues and in real-time dynamic distribution monitoring in vivo, which laid a foundation for further clinical applications in OS. Moreover, we demonstrated that PDT guided by the constructed NPs could significantly induce HOS cells apoptosis and ferroptosis via excessive accumulation of reactive oxygen species (ROS), and further determined that the potential anticancer molecular mechanism of apoptosis was triggered by the release of cytochrome c-activated mitochondrial apoptosis (endogenous apoptosis), and that ferroptosis caused the activation of nuclear receptor coactivator 4 (NCOA4)-mediated ferritinophagy and the inactivation of glutathione peroxidase 4 (GPX4), synergistically leading to excessive accumulation of Lipid-ROS and Lipid peroxides (LPOs). Concurrently, MH-PLGA-IR780 NPs-guided PDT also showed an obvious inhibitory effect on tumor growth in vivo. CONCLUSION: These results suggest that this homologous targeting-based theranostic nanoplatform provides an effective method to improve PDT performance in OS and contributes a new and promising approach for OS therapy.

Inhalation toxicity of polystyrene micro(nano)plastics using modified OECD TG 412.

Recently, there have been reports that many microplastics are found in the air, which has raised concerns about their toxicity. To date, however, only limited research has investigated the effects of micro(nano)plastics on human health, and even less the potential for inhalation toxicity. To fill this research gap, we investigated the potential inhalation toxicity of micro(nano)plastics using a modified OECD Guideline for Testing of Chemicals No. 412 '28-Day (subacute) inhalation toxicity study' using a whole-body inhalation system. Sprague-Dawley rats were exposed to three different exposure concentrations of polystyrene micro(nano)plastics (PSMPs), as well as control, for 14 days of inhalation exposure. After 14 days, alterations were observed on sevral endpoints in physiological, serum biochemical, hematological, and respiratory function markers measured on the samples exposed to PSMPs. However, no concentration-response relationships were observed, suggesting that these effects may not be definitively linked to exposure of PSMPs. On the other hand, the expression of inflammatory proteins (TGF-ß and TNF-α) increased in the lung tissue in an exposure concentration-dependent manner. The overall results indicate that 14-day inhalation exposure of PSMPs to rats has a more pronounced effect at the molecular level than at the organismal one. These results suggest that if the exposure sustained, alterations at the molecular level may lead to subsequent alterations at the higher levels, and consequently, the health risks of inhalation exposed micro(nano)plastics should not be neglected.

Gold nanoparticles as a promising treatment for diabetes and its complications: Current and future potentials

Diabetes and its complications represent a major cause of morbidity and mortality in diabetes patients. This review is aimed to find the potential of gold nanoparticles (AuNPs) to act as therapeutic agents for diabetes and its complications. Here, we outline the literature related to the self-therapeutic effects of AuNPs. The first goal of this review is to highlight and summarize some of the existing studies (10 years ago) in terms of several parameters such as the size of AuNPs, dose, administration route, experimental model, experimental analysis, and findings. The second goal is to describe the self-therapeutic effects of AuNPs against the pathogenesis determinants of diabetic complications. AuNPs have been found to have inhibitory effects on transforming growth factor-ß, antiglycation, antiangiogenic, anti-hyperglycemic, anti-inflammatory, and antioxidant effects. AuNPs treatment effectively disrupts multiple pathogenesis determinants in an animal model of diabetes and diabetic complications. The present review provides insight into the potential applications of AuNPs, which may help reduce the incidence of diabetes and its complications

From cheese whey permeate to Sakacin-A/bacterial cellulose nanocrystal conjugates for antimicrobial food packaging applications: a circular economy case study.

Applying a circular economy approach, this research explores the use of cheese whey permeate (CWP), by-product of whey ultrafiltration, as cheap substrate for the production of bacterial cellulose (BC) and Sakacin-A, to be used in an antimicrobial packaging material. BC from the acetic acid bacterium Komagataeibacter xylinus was boosted up to 6.77 g/L by supplementing CWP with ß-galactosidase. BC was then reduced to nanocrystals (BCNCs, 70% conversion yield), which were then conjugated with Sakacin-A, an anti-Listeria bacteriocin produced by Lactobacillus sakei in a CWP based broth. Active conjugates (75 Activity Units (AU)/mg), an innovative solution for bacteriocin delivery, were then included in a coating mixture applied onto paper sheets at 25 AU/cm2. The obtained antimicrobial food package was found effective in reducing Listeria population in storage trials carried out on a fresh Italian soft cheese (named "stracchino") intentionally inoculated with Listeria. Production costs of the active material have been mainly found to be associated (90%) to the purification steps. Setting a maximum prudential 50% cost reduction during process up-scaling, conjugates coating formulation would cost around 0.89 €/A4 sheet. Results represent a practical example of a circular economy production procedure by using a food industry by-product to produce antimicrobials for food preservation.

Assessment of nicotine release from nicotine-loaded chitosan nanoparticles dry powder inhaler formulations via locomotor activity of C57BL/6 mice.

PURPOSE: This study aimed to assess the activity of controlled release nicotine from dry powder inhaler formulation via locomotor activity of C57BL/6 mice. METHODS: To achieve this we built a nose-only inhalation device for pulmonary administration of nicotine to mice and determined the optimal operational parameters. We used the locomotor activity test to compare the effects of the inhaled nicotine hydrogen tartrate-loaded chitosan nanoparticles (NHT-CS) with NHT in C57BL/6 mice. The minimum inhaled dose of NHT-CS required to alter locomotor activity was compared with inhaled and subcutaneously (s.c) injected NHT. Finally, histological examination of lung tissues was performed to ensure inhalation of NHT-CS did not cause lung damage. RESULTS: We found a flow rate of 0.9 L/min and an exposure time of 5 min achieved optimal delivery of nicotine. A minimum of 0.88 mg inhaled of NHT-CS or 0.59 mg inhaled of NHT was required to alter locomotor activity similarly to injection of 0.5 mg/kg nicotine, suggesting the reformulation process did not alter the activity of NHT-CS. No differences between untreated and NHT-CS treated lung tissue upon histological examination were observed. CONCLUSIONS: The results indicated the inhaled NHT-CS is a viable preclinical option for developing novel inhalation formulations as a potential anti-smoking therapeutic.

In Situ, Quantitative Assessment of Multifunctional Nanoscale Drug Delivery Systems in Human Serum.

The large volume and diversified nanomedicine market, undergoing a rapid growth, relies not only on the creation and applicative exploration of nanocarrier-based medicines showing significant potential, but in particular, demands a quantitative assessment of their physicochemical properties. In this study, we demonstrate the in situ assessment of multifunctional biodegradable nanoparticle (NP) entries as core components of nanoscale drug delivery systems (NDDSs) by making use of analytical ultracentrifugation (AUC). We determine and elucidate the following characteristics of NPs in NDDSs: NP density and size, targeting dye functionality, encapsulated and free drug, surfactant, and also NP drug release dynamics, quantitatively interconnected to NP degradation. In concept, we demonstrate this by multidetection AUC experiments at variable speed and time profiles. We could verify the quantitative and accurate nature of AUC for assessment of NDDSs, that is, also future nanomedicines. This concerns modeled and real life solution application formats such as cell culture media and human serum.

Oxiconazole nitrate solid lipid nanoparticles: formulation, in-vitro characterization and clinical assessment of an analogous loaded carbopol gel.

The aim of the present work was to develop a promising drug delivery system of oxiconazole nitrate-loaded solid lipid nanoparticles (SLNs) topical gel to enhance the drug effectiveness for the treatment of Tinea infection. SLNs were prepared by emulsification-solvent evaporation method. Particle size and entrapment efficiency of the prepared SLNs were investigated. An appropriate formulation was selected and examined for morphology and physicochemical characterization adopting Scanning electron microscope and Differential scanning colorimetry. In-vitro drug release was also investigated. The selected SLNs were loaded into 1% Carbopol 934 gel that was investigated for homogeneity, pH, grittiness, spreadability, viscosity and in vitro drug release. Clinical study for the developed gel system compared to the corresponding marketed product was conducted on 28 patients. The results revealed that the prepared oxiconazole nitrate SLNs had drug entrapment efficiency ranging from 41.34% to 75.07% and zeta potential lying between -13 and -50. Physicochemical characterization revealed a decrease in the drug crystallinity in the prepared SLNs. The gel formulation showed appropriate physical characteristics and sustained in-vitro drug release. Clinical study for the prepared oxiconazole nitrate SLNs gel showed significantly less side effects, better patient satisfaction and superior clinical improvement compared with the corresponding marketed product.

Safety assessment of cerium oxide nanoparticles: combined repeated-dose toxicity with reproductive/developmental toxicity screening and biodistribution in rats.

Cerium oxide nanoparticles (CeO2 NPs) are widely used in various commercial applications because of their characteristic properties. People can be easily exposed to CeO2 NPs in real life, but the safety assessment of CeO2 NPs has not been fully investigated. Therefore, in this study, we conducted a combined repeated-dose and reproductive/developmental toxicity screening study (OECD testing guideline 422) to investigate the potential hazards on human health, including reproductive/developmental functions, after repeated daily CeO2 NPs oral gavage administration to both males and females. In addition, tissues from parental animals and their pups were collected to analyze the internal accumulation of cerium. CeO2 NPs were orally administered to Sprague-Dawley rats at doses of 0, 100, 300 and 1000 mg/kg during their pre-mating, mating, gestation and early lactation periods. In the general systemic and reproductive/developmental examinations, no marked toxicities were observed in any in-life and terminal observation parameters in this study. In the biodistribution analysis, cerium was not detected in either parental or pup tissues (blood, liver, lungs and kidneys). Repeated oral exposure of CeO2 NPs did not induce marked toxicities affecting general systemic and reproductive/developmental functions up to the dose level of 1000 mg/kg and the CeO2 NPs were not systemically absorbed in parental animals or their pups. This result could be used in risk assessment for humans, and additional toxicity studies with CeO2 NPs will be necessary considering various physicochemical properties and exposure probabilities of these nanoparticles.

Glibenclamide nanosuspension inhaler: development, in vitro and in vivo assessment.

Objective: The development of nanosuspension for targeted delivery of glibenclamide as hypoglycemic agent to the lung in an inhaler dosage form.Method: Glibenclamide nanosuspension formulations were prepared using Box-Behnken design to investigate the effect of independent factors on the dependent variables, Fourier-transform Infrared spectroscopy, Differential Scanning Calorimetry, evaluation of glibenclamide nanosuspension inhaler and in vivo hypoglycemic efficacy were performed to determine glibenclamide nanosuspension inhaler effect.Results: The results revealed that the mean particle sizes of the prepared nanosuspension ranged from 0.216 to 0.856 µm, zeta potential from +9 to +16 mV, the solubility ranged from 43% to 75%, the mass median aerodynamic diameter was 2.34 µm and the glucose level in rat was significantly reduced by about 60%.Conclusion: These results confirmed that glibenclamide nanosuspension inhaler enhance hypoglycemic effectiveness and reduce adverse effect of glibenclamide, opening up new dosage form in Diabetes mellitus treatment.

The cytotoxicity of nanomaterials: Modeling multiple human cells uptake of functionalized magneto-fluorescent nanoparticles via nano-QSAR.

The vast majority of nanomaterials have attracted an upsurge of interest since their discovery and considerable researches are being carried out about their adverse outcomes for human health and the environment. In this study, two regression-based quantitative structure-activity relationship models for nanoparticles (nano-QSAR) were established to predict the cellular uptakes of 109 functionalized magneto-fluorescent nanoparticles to pancreatic cancer cells (PaCa2) and human umbilical vein endothelial cells (HUVEC) lines, respectively. The improved SMILES-based optimal descriptors encoded with certain easily available physicochemical properties were proposed to describe the molecular structure characteristics of the involved nanoparticles, and the Monte Carlo method was used for calculating the improved SMILES-based optimal descriptors. Both developed nano-QSAR models for cellular uptake prediction provided satisfactory statistical results, with the squared correlation coefficient (R2) being 0.852 and 0.905 for training sets, and 0.822 and 0.885 for test sets, respectively. Both models were rigorously validated and further extensively compared to literature models. Predominant physicochemical features responsible for cellular uptake were identified by model interpretation. The proposed models could be reasonably expected to provide guidance for synthesizing or choosing safer, more suitable surface modifiers of desired properties prior to their biomedical applications.

Need for speed: Super-resolving the dynamic nanoclustering of syntaxin-1 at exocytic fusion sites.

Communication between cells relies on regulated exocytosis, a multi-step process that involves the docking, priming and fusion of vesicles with the plasma membrane, culminating in the release of neurotransmitters and hormones. Key proteins and lipids involved in exocytosis are subjected to Brownian movement and constantly switch between distinct motion states which are governed by short-lived molecular interactions. Critical biochemical reactions between exocytic proteins that occur in the confinement of nanodomains underpin the precise sequence of priming steps which leads to the fusion of vesicles. The advent of super-resolution microscopy techniques has provided the means to visualize individual molecules on the plasma membrane with high spatiotemporal resolution in live cells. These techniques are revealing a highly dynamic nature of the nanoscale organization of the exocytic machinery. In this review, we focus on soluble N-ethylmaleimide-sensitive factor attachment receptor (SNARE) syntaxin-1, which mediates vesicular fusion. Syntaxin-1 is highly mobile at the plasma membrane, and its inherent speed allows fast assembly and disassembly of syntaxin-1 nanoclusters which are associated with exocytosis. We reflect on recent studies which have revealed the mechanisms regulating syntaxin-1 nanoclustering on the plasma membrane and draw inferences on the effect of synaptic activity, phosphoinositides, N-ethylmaleimide-sensitive factor (NSF), α-soluble NSF attachment protein (α-SNAP) and SNARE complex assembly on the dynamic nanoscale organization of syntaxin-1. This article is part of the special issue entitled 'Mobility and trafficking of neuronal membrane proteins'.

Predictive Metabolomic Signatures for Safety Assessment of Metal Oxide Nanoparticles.

The widespread use of metal oxide nanoparticles (MOx NPs) poses a risk of exposure that may lead to adverse health effects on humans. Even though a number of toxicological methodologies are available for assessing nanotoxicity, the effect of MOx NPs on cell metabolism in vitro and in vivo remains largely unknown, especially under the exposure to low-dose or supposedly low-toxicity MOx NPs. In this study, liquid chromatography-mass spectrometry (LC-MS) based metabolomics was used to reveal significantly altered metabolites and metabolic pathways in human bronchial epithelial cells exposed to four different types of MOx NPs (ZnO, SiO2, TiO2, and CeO2) at both high (25 µg/mL) and low (12.5 µg/mL) doses. We demonstrated that high-dose ZnO NPs caused severe cytotoxicity with altered metabolism of amino acids, nucleotides, nucleosides, tricarboxylic acid cycle, lipids, inflammation/redox, and fatty acid oxidation, as well as the elevation of toxic and DNA damage related metabolites. Fewer metabolomic alterations were induced by low-dose ZnO NPs. However, most metabolites significantly altered by high-dose ZnO NPs were also slightly changed by low-dose ZnO NPs. On the other hand, the cells exposed to SiO2, TiO2, and CeO2 NPs at either high or low dose displayed low cytotoxicity with similar metabolomic alterations, although each type of NPs induced distinct changes of certain metabolites. These three NPs significantly affected the metabolic pathways of sphingosine-1-phosphate, fatty acid oxidation, folate cycle, inflammation/redox, and lipid metabolism. In addition, dose-dependent effects were observed for a number of metabolites significantly altered by respective MOx NPs. Representative metabolites of the significantly altered metabolic pathways were successfully validated in vitro using enzymatic assays. More importantly, these representative metabolites were further validated in a mouse model after lung exposure to respective NPs, indicating that in vitro metabolomic findings may be used to effectively predict the toxicological effects in vivo. Despite functional assay results demonstrating that the changes in cellular functions were largely reflected by the metabolomic alterations, LC-MS-based metabolomics was sensitive enough to detect the subtle metabolomic changes when functional cellular assays showed no significant difference. Collectively, our studies have unveiled potential metabolic mechanisms of MOx NP-induced nanotoxicity in lung epithelial cells and demonstrated the sensitivity and feasibility of using metabolomic signatures to understand and predict nanotoxicity in vivo.

Development and Assessment of Lipidic Nanoemulsions Containing Sodium Hyaluronate and Indomethacin.

The present work attempts to develop and optimize the formula of a lipidic nanoemulsion (NE) containing sodium hyaluronate (HNa) and indomethacin (Ind) as HNa-Ind for enhanced transdermal antiarthritic activity. NEs were prepared by the spontaneous emulsification method and characterized by Fourier-transform infrared (FTIR) spectroscopy. The composition of the optimal formulation was statistically optimized using Box-Behnken experimental design method with three independent factors and was characterized for particle size, polydispersity index, and percent transmittance. The selected formula was tested for its in vitro antioxidant activity and in vivo anti-inflammatory activity. The optimized HNa-Ind NE formula was characterized and displayed a particle size of 12.87 ± 0.032 nm, polydispersity index of 0.606 ± 0.082, and 99.4 ± 0.1 percentage of transmittance. FTIR showed no interaction between HNa and Ind as a physical mixture. In addition, the optimized HNa-Ind NE was able to preserve the antioxidant ability of the two drugs, as evidenced through a 2,2-diphenyl-1-picrylhydrazyl (DPPH) inhibition assay used to assess free radical scavenging ability. The cell viability was increased while the free radical scavenging activity was decreased (94.28% inhibition at higher concentrations compared with vitamin C as a reference with an inhibition of 100%). Moreover, the pharmacological anti-inflammatory potential of the optimized HNa-Ind NE formulation was assessed using an in vivo model. Compared with reference drugs (ibuprofen gel 5%), the remarkable activity of the optimized formulation was established using xylene-induced ear edema in mice model, in which the inflamed region reduced by 92.5% upon treatment. The optimized HNa-Ind NE formulation showed considerably higher skin permeation and drug deposition capability compared with the HNa-Ind solution. HNa-Ind NE was demonstrated to be a successful carrier with enhanced antioxidant and anti-inflammatory potential while showing better skin penetration, thus being a promising vehicle for transdermal drug delivery.

Assessment of titanium dioxide nanoparticles toxicity via oral exposure in mice: effect of dose and particle size.

Objective: The aim of the present work is to evaluate the toxicity of titanium dioxide nanoparticles (TiO2NPs) according to their doses and particle sizes. Materials and methods: The effect of five days oral administration of TiO2NPs (21 and 80 nm) with different doses (50, 250 and 500 mg/kg body weight) was assessed in mice via measurement of oxidative stress markers; glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA) and nitric oxide (NO), liver function indices; aspartate and alanine aminotransferases (AST and ALT), chromosomal aberrations and liver histopathological pattern. Results: The results revealed drastic alterations in all the measured parameters and showed positive correlation with the gradual dose increment. In addition, the smaller particle size of TiO2NPS (21 nm) had more adverse effect in all the selected biochemical parameters, genetic aberrations and histological investigations. Conclusions: Toxicity of TiO2NPs increases in a dose-dependent manner and vice versa with particles size. The evaluated biomarkers are good indicators for TiO2NPs toxicity. More detailed studies are required before the recommendation of TiO2NPS as food additives.

Beta-carotene-Encapsulated Solid Lipid Nanoparticles (BC-SLNs) as Promising Vehicle for Cancer: an Investigative Assessment.

Beta-carotene (BC), a red-colored pigment found in plants and animals, is one of the most extensively investigated carotenoids due to its provitamin-A, antioxidant, and anticancer properties. The anticancer activity of BC through oral administration is severely affected due to its low bioavailability and oxidative degradation. The present study aimed to formulate and characterize solid lipid nanoparticles (SLNs) of BC for enhanced bioavailability and therapeutic efficacy. Beta-carotene-loaded solid lipid nanoparticles (BC-SLNs) were prepared employing different combinations of glyceryl monostearate and gelucire. The characterization studies were performed for particle size, morphology, release behavior, and stability. BC-SLNs were also studied for in vitro cytotoxicity in human breast cancer cell lines (MCF-7) and pharmacokinetic studies in Wistar rats. The cytotoxicity studies confirmed that encapsulation of BC within the lipid bilayers of nanoparticles did not affect its anticancer efficacy. An improved anticancer activity was observed in BC-SLNs as compared to the free BC. BC-SLNs enhanced the bioavailability of BC on oral administration by sustaining its release from the lipid core and prolongation of circulation time in the body. Similarly, area under the curve (AUCtotal) enhanced 1.92-times more when BC was incorporated into SLNs as compared to free BC. In conclusion, solid lipid nanoparticles could be an effective and promising strategy to improve the biopharmaceutical properties of carotenoids for anticancer effects.

23 Na Triple-quantum signal of in vitro human liver cells, liposomes, and nanoparticles: Cell viability assessment vs. separation of intra- and extracellular signal.

BACKGROUND: Triple-quantum (TQ) filtered sequences have become more popular in sodium MR due to the increased usage of scanners with field strengths exceeding 3T. Disagreement as to whether TQ signal can provide separation of intra- and extracellular compartments persists. PURPOSE: To provide insight into TQ signal behavior on a cellular level. STUDY TYPE: Prospective. PHANTOM/SPECIMEN: Cell-phantoms in the form of liposomes, encapsulated 0 mM, 145 mM, 154 mM Na+ in a double-lipid membrane similar to cells. Poly(lactic-co-glycolic acid) nanoparticles encapsulated 154 mM Na+ within a single-layer membrane structure. Two microcavity chips with each 6 × 106 human HEP G2 liver cells were measured in an MR-compatible bioreactor. FIELD STRENGTH/SEQUENCE: Spectroscopic TQ sequence with time proportional phase-increments at 9.4T. ASSESSMENT: The TQ signal of viable, dead cells, and cell-phantoms was assessed by a fit in the time domain and by the amplitude in the frequency domain. STATISTICAL TESTS: The noise variance (σ) was evaluated to express the deviation of the measured TQ signal amplitude from noise. RESULTS: TQ signal >20σ was found for liposomes encapsulating sodium ions. Liposomal encapsulation of 0 mM Na+ and 154 mM Na+ encapsulation in the nanoparticles resulted in <2σ TQ signal. Cells under normal perfusion resulted in >9σ TQ signal. Compared with TQ signal under normal perfusion, a 56% lower TQ signal of was observed (25σ) during perfusion stop. TQ signal returned to 92% of the initial signal after reperfusion. DATA CONCLUSION: Our measurements indicate that TQ signal in liposomes was observed due to the trapping of ions within the double-lipid membrane rather than from the intraliposomal space. Transfer to the cell results suggests that TQ signal was observed from motion restriction equivalent to trapping. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2019;50:435-444.