Ultrasound Sonication Research Articles

Ultrasonic-assisted extraction and automated determination of catalase and lipase activities in bovine and poultry livers using a digital movie-based flow-batch analyzer

An ultrasonic reactor (UR) was developed and coupled to a digital movie-based flow-batch analyzer (DM-FBA) for the ultrasonic-assisted extraction (UAE) and fast determination of catalase and lipase activities in bovine and poultry livers. The lab-made UR mainly consisted of a borosilicate glass container and a piezoelectric disc. The DM-FBA mainly consisted of a webcam, an ultrasonic actuator controller, a peristaltic pump, six solenoid valves, a valve driver, a mixing chamber, a magnetic stirrer, an Arduino Mega 2560, and a personal computer. This setup, named UR-DM-FBA, was controlled by custom software. Ultrasound (US) frequency, US power, sonication time, and concentration of extraction agent were optimized using the Taguchi method. Experiments at silent conditions (mechanical stirring at 1500 rpm) were carried out to evaluate extraction efficiency. Optimized parameters for the UAE of catalase were US frequency of 30 kHz, 2.0 mL of Triton X-100, sonication time of 270 s, and US power of 10.8 W. For the UAE of lipase, the optimized parameters were US frequency of 20 kHz, 0.30 mL of triethanolamine, sonication time of 270 s, and US power of 18 W. Catalase and lipase activities obtained with the UR were, on average, 1.9 × 103% and 2.0 × 103% higher than those obtained at silent conditions, respectively, which indicates that that the lab-made UR was capable of extracting these enzymes more efficiently. Determinations using the UR-DM-FBA were highly accurate (relative error ranging from −1.98% to 1.96% for bovine catalase, −0.65% to 0.76% for bovine lipase, −2.03 to 2.08% for poultry catalase, and −0.55% to 0.64% for poultry lipase) and precise (overall coefficient of variation <0.02% for bovine and poultry catalase and <0.2% for bovine and poultry lipase). Results obtained with the proposed system and reference methods were in good agreement according to the paired t-test (95% confidence level). High sampling rates (>69 h−1) and low sample/reagent consumption (<1.6 mL) were also obtained. Due to the highly efficient UAE, the proposed system can be applied for fast and accurate quantification of lipase and catalase in biological samples with low waste generation.

Focused ultrasound-enhanced delivery of intranasally administered anti-programmed cell death-ligand 1 antibody to an intracranial murine glioma model

Immune checkpoint inhibitors have great potential for treating the gliomas; however, their therapeutic efficacy has been partially limited by their inability to cross the blood–brain barrier (BBB). The objective of this study was to evaluate the capability of focused-ultrasound-mediated intranasal brain drug delivery (FUSIN) in achieving the locally enhanced delivery of anti-programmed cell death-ligand 1 antibody (aPD-L1) to the brain. aPD-L1 was labeled with a near-infrared fluorescence dye (IRDye 800CW) and administered to mice through the nasal route to the brain, followed by focused ultrasound sonication in the presence of systemically injected microbubbles. FUSIN enhanced the accumulation of aPD-L1 at the FUS-targeted brainstem by an average of 4.03- and 3.74-fold compared with intranasal (IN) administration alone in the non-tumor mice and glioma mice, respectively. Immunohistochemistry staining found that aPD-L1 was mainly located within the perivascular spaces after IN delivery, while FUSIN further enhanced the penetration depth and delivery efficiency of aPD-L1 to the brain parenchyma. The delivered aPD-L1 was found to be colocalized with the tumor cells after FUSIN delivery to the brainstem glioma. These findings suggest that FUSIN is a promising technique to enhance the delivery of immune checkpoint inhibitors to gliomas.

Extraction and determination of strobilurin fungicides residues in apple samples using ultrasound-assisted dispersive liquid-liquid microextraction based on a novel hydrophobic deep eutectic solvent followed by H.P.L.C-U.V

ABSTRACT In this study, several novel and natural hydrophobic deep eutectic solvents (D.E.Ss) were prepared using methyl trioctylammonium chloride (M.T.O.A.C) as H.B.A and different types of straight chain alcohols as H.B.Ds. One of the D.E.Ss composed of M.T.O.A.C and n-butanol was advantageously used to develop an ultrasound-assisted dispersive liquid-liquid microextraction (U.A−D.L.L.M.E) method combined with high-performance liquid chromatography-ultraviolet detection (H.P.L.C−U.V) for the determination of some strobilurin fungicides in apple samples. Several important parameters influencing extraction efficiency were investigated and optimised, including the type and volume of extractant in ultrasound stage, sonication time, the type and volume of D.E.S, sample solution pH and effect of salt addition. Under optimal experimental conditions, the method showed good linearity with correlation coefficients (R 2) of 0.9985 − 0.9991 in the linear range of 4−1500 μg kg−1, low limits of detection of 1.5−2 μg kg−1 and acceptable extraction recoveries in the range of 76−92%. Enrichment factor was in the range of 95–115. The proposed method was successfully applied for the extraction and preconcentration of trace fungicides in apple samples, and the results demonstrated the potential of the synthesised D.E.S for the extraction and determination of contaminants in aqueous samples.

Atherosclerotic lesion-specific copper delivery suppresses atherosclerosis in high-cholesterol-fed rabbits.

Dietary cholesterol supplements cause hypercholesterolemia and atherosclerosis along with a reduction of copper concentrations in the atherosclerotic wall in animal models. This study was to determine if target-specific copper delivery to the copper-deficient atherosclerotic wall can block the pathogenesis of atherosclerosis. Male New Zealand white rabbits, 10-weeks-old and averaged 2.0 kg, were fed a diet containing 1% (w/w) cholesterol or the same diet without cholesterol as control. Twelve weeks after the feeding, the animals were injected with copper-albumin microbubbles and subjected to ultrasound sonication specifically directed at the atherosclerotic lesions (Cu-MB-US) for target-specific copper delivery, twice a week for four weeks. This regiment was repeated 3 times with a gap of two weeks in between. Two weeks after the last treatment, the animals were harvested for analyses of serum and aortic pathological changes. Compared to controls, rabbits fed cholesterol-rich diet developed atherosclerotic lesion with a reduction in copper concentrations in the lesion tissue. Cu-MB-US treatment significantly increased copper concentrations in the lesion, and reduced the size of the lesion. Furthermore, copper repletion reduced the number of apoptotic cells as well as the content of cholesterol and phospholipids in the atherosclerotic lesion without a disturbance of the stability of the lesion. The results thus demonstrate that target-specific copper supplementation suppresses the progression of atherosclerosis at least in part through preventing endothelial cell death, thus reducing lipid infiltration in the atherosclerotic lesion.

Static Magnetic Fields Dampen Focused Ultrasound-mediated Blood-Brain Barrier Opening.

Background Focused ultrasound combined with microbubbles has been used in clinical studies for blood-brain barrier (BBB) opening in conjunction with MRI. However, the impact of the static magnetic field generated by an MRI scanner on the BBB opening outcome has not been evaluated. Purpose To determine the relationship of the static magnetic field of an MRI scanner on focused ultrasound combined with microbubble-induced BBB opening. Materials and Methods Thirty wild-type mice were divided into four groups. Mice from different groups were sonicated with focused ultrasound in different static magnetic fields (approximately 0, 1.5, 3.0, and 4.7 T), with all other experimental parameters kept the same. Focused ultrasound sonication was performed after intravenous injection of microbubbles. Microbubble cavitation activity, the fundamental -physical mechanism underlying focused ultrasound BBB opening, was monitored with passive cavitation detection. After sonication, contrast-enhanced T1-weighted MRI was performed to assess BBB opening outcome. Intravenously injected Evans blue was used as a model agent to evaluate trans-BBB delivery efficiency. Results The microbubble cavitation dose decreased by an average of 2.1 dB at 1.5 T (P = .05), 2.9 dB at 3.0 T (P = .01), and 3.0 dB at 4.7 T (P = .01) compared with that outside the magnetic field (approximately 0 T). The static magnetic field of an MRI scanner decreased BBB opening volume in mice by 3.2-fold at 1.5 T (P < .001), 4.5-fold at 3.0 T (P < .001), and 11.6-fold at 4.7 T (P <.001) compared with mice treated outside the magnetic field. It also decreased Evans blue trans-BBB delivery 1.4-fold at 1.5 T (P = .009), 1.6-fold at 3.0 T (P < .001), and 1.9-fold at 4.7 T (P < .001). Conclusion Static magnetic fields dampened microbubble cavitation activity and decreased trans-blood-brain barrier (BBB) delivery by focused ultrasound combined with microbubble-induced BBB opening. © RSNA, 2021 An earlier incorrect version of this article appeared online. This article was corrected on July 8, 2021.

Safety of focused ultrasound neuromodulation in humans with temporal lobe epilepsy

ObjectiveTranscranial Focused Ultrasound (tFUS) is a promising new potential neuromodulation tool. However, the safety of tFUS neuromodulation has not yet been assessed adequately. Patients with refractory temporal lobe epilepsy electing to undergo an anterior temporal lobe resection present a unique opportunity to evaluate the safety and efficacy of tFUS neuromodulation. Histological changes in tissue after tFUS can be examined after surgical resection, while further potential safety concerns can be assessed using neuropsychological testing. MethodsNeuropsychological functions were assessed in eight patients before and after focused ultrasound sonication of the temporal lobe at intensities up to 5760 mW/cm2. Using the BrainSonix Pulsar 1002, tFUS was delivered under MR guidance, using the Siemens Magnetom 3T Prisma scanner. Neuropsychological changes were assessed using various batteries. Histological changes were assessed using hematoxylin and eosin staining, among others. ResultsWith respect to safety, the histological analysis did not reveal any detectable damage to the tissue, except for one subject for whom the histology findings were inconclusive. In addition, neuropsychological testing did not show any statistically significant changes in any test, except for a slight decrease in performance on one of the tests after tFUS. SignificanceThis study supports the hypothesis that low-intensity Transcranial Focused Ultrasound (tFUS) used for neuromodulation of brain circuits at intensities up to 5760 mW/cm2 may be safe for use in human research. However, due to methodological limitations in this study and inconclusive findings, more work is warranted to establish the safety. Future directions include greater number of sonications as well as longer exposure at higher intensity levels to further assess the safety of tFUS for modulation of neuronal circuits.

NIR‐II Fluorescence imaging for cerebrovascular diseases

AbstractAs the major pipeline for transporting oxygen and nutrients to living tissues, well‐ordered and functional vasculature is vital to maintain the function of organisms. The cerebrovascular disorders induced by acute or chronic diseases, including traumatic brain injury (TBI), stroke, and brain tumors, could cause vascular cognitive impairment and even mortality. Due to the complication of these cerebrovascular diseases, early diagnosis and monitoring their pathological processes in real time in animal models could enlighten us with insights into early prevention and effective treatment. Over the last decade, the NIR‐II fluorescence imaging technology has been well developed in both nanofluorophores and imaging systems. For cerebrovascular disorders, the collaborative use of wide‐field imaging setup with NIR‐II nanoprobes enable arteriovenous staging, and calculation of blood flow velocity to distinguish ischemic area in TBI and stroke. The changes in molecular and cellular levels of TBI provide the guidance on the design of targeted and activatable NIR‐II nanoprobes for evaluating and monitoring the microenvironment variations. For the brain tumors, both targeted strategy and focus ultrasound sonication are efficient approaches for overcoming the blood‐brain‐barrier and brain‐tumor‐barrier for delivery of nanoprobes. Therefore, NIR‐II fluorescence imaging‐guided surgical navigation of brain tumors and resected lesions biopsy intraoperatively ensure the accuracy of surgery based on the precise definition of tumor margins. This review summarizes the recent advances in NIR‐II fluorescence imaging technology, which is mainly inclusive of well‐developed NIR‐II nanofluorophores and their applications in cerebrovascular diseases with address of its challenges and great potential in these aspects.

Chemical characterisation of Pelargonium sidoides root based on LC-QToF-MS non-target screening strategies.

Pelargonium sidoides is a member of the Geraniaceae family and it originates from the coastal regions of South Africa. In the last decades, Pelargonium sidoides root has been subjected to several surveys due to the assertion of its health benefits, such as the relief of symptoms of acute bronchitis, common cold and acute rhinosinusitis. Many studies have been conducted to reveal its naturally occurring bioactive chemicals, yet no wide-scope chemical characterisation strategies have been done using mass spectrometry. This research aimed to comprehensively characterise the chemical profile of Pelargonium sidoides root via high-resolution mass spectrometry. The Pelargonium sidoides root was extracted by a mixture of methanol: water in the proportion of 80:20. The extraction procedure included vortexing, shaking as well as the use of an ultrasound sonication bath under 40°C. After centrifugation, the supernatant was evaporated to dryness. The dry residue was reconstituted with a mixture of methanol/water (50:50, v/v), filtered and injected into an ultra-high-pressure liquid chromatography-quadruple time-of-flight mass spectrometer. Overall, 33 compounds were identified in the root using suspect and non-target screening. These compounds were originated from different classes of compounds such as amino acids, phenolic acids, α-hydroxy-acids, vitamins, polyphenols, flavonoids, coumarins, coumarins glucosides, coumarin sulphates and nucleotides. Quantitative results were provided for the identified compounds, where their reference standards were available. Some important compounds were elucidated, belonging to different classes of compounds such as antioxidants (coumarins and phenolic compounds), amino acids, nucleotides and vitamins revealing the importance of the bioactive content of this root.

Effect of Process Parameters on Extraction of Pectin from Sweet Lime Peels

Pectin is a heterogeneous polysaccharide found in the cell wall, middle lamellae of many fruits and vegetables, and is widely used as gelling agent, emulsifier and stabilizer in food industry. In keeping the importance of pectin in the food industry, ultrasound-assisted extraction of pectin from sweet lime peel was investigated. The individual and interactive effect of solid-solvent ratio, ultrasound power intensity and sonication time on the pectin yield, equivalent weight and methoxyl content were studied and analyzed using multiple regression analysis. The maximum pectin yield (36.4 g/100 g), equivalent weight (740.3 mg) and methoxyl content (7.1%) was obtained under optimal condition (solid-solvent ratio of 1:24.3 g/ml, ultrasound power intensity of 80 W/cm2 and sonication time of 18.4 min). Significant (p < 0.05) effect of process parameters was found in all responses of pectin extracted from sweet lime peel. It was also revealed from the present study that ultrasound-assisted extraction of pectin from sweet lime peel is an efficient approach toward waste valorization and extraction of pectin with high yield and good quality attributes.

Development of a multi-functional preclinical device for the treatment of glioblastoma.

Glioblastoma multiforme (GBM) is one of the most common and aggressive malignant primary brain tumors in adults. The treatment of GBM is limited by the blood-brain barrier (BBB), which limits the diffusion of appropriate concentrations of therapeutic agents at the tumor site. Among experimental therapies, photo-thermal therapy (PTT) mediated by nanoparticles is a promising strategy. To propose a preclinical versatile research instrument for the development of new PTT for GBM, a multipurpose integrated preclinical device was developed. The setup is able to perform: i) BBB permeabilization by focused ultrasound sonication (FUS); ii) PTT with continuous wave laser; iii) in situ temperature monitoring with photo-acoustic (PA) measurements. In vivo preliminary subcutaneous and transcranial experiments were conducted on healthy or tumor-bearing mice. Transcranial FUS-induced BBB permeabilization was validated using single photon emission computed tomography (SPECT) imaging. PTT capacities were monitored by PA thermometry, and are illustrated through subcutaneous and transcranial in vivo experiments. The results show the therapeutic possibilities and ergonomy of such integrated device as a tool for the validation of future treatments.

One-minute and green synthesis of magnetic iron oxide nanoparticles assisted by design of experiments and high energy ultrasound: Application to biosensing and immunoprecipitation

The present study is focused on the ultrafast and green synthesis, via the co-precipitation method, of magnetic nanoparticles (MNPs) based on iron oxides using design of experiments (DOE) and high energy sonochemical approach, considering two main factors: amplitude (energy) of the ultrasound probe and sonication time. The combination of these techniques allowed the development of a novel one-minute green synthesis, which drastically reduced the amount of consumed energy, solvents, reagents, time and produced residues. This green sonochemical synthesis permitted to obtain mean particle sizes of 11 ± 2 nm under the optimized conditions of amplitude = 40% (2826 J) and time = 1 min. Their composition, structure, size, morphology and magnetic properties were assessed through X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning and transmission electron microscopy (SEM & TEM), and vibrating sample magnetometry (VSM). The characterization results indicate the proper formation of MNPs, and the correct functionalization of MNPs with different coating agents. The functionalized MNPs were used as: i) biosensor, which could detect mercury in water in the range of 0.030–0.060 ppm, and ii) support onto which polyclonal antibodies were anchored and successfully bound to an osteosarcoma cell line expressing the target protein (TRIB2-GFP), as part of an immunoprecipitation assay.

Application of Green Nanocomposite to Adsorb Cadmium ion in Wastewater

Under to the development of the industrialization, people have polluted the water source with chemicals and wastes from factories and enterprises. These chemicals are not treated and discharged directly to the natural environment, especially heavy metals. Cadmium and its compounds are released to the environment from different sources of waste, such as metal, alloy and metal plating, and Cd-Ni batteries, which clearly showed a danger to the human health. In this work, silicon oxide nanoparticles (SiO2) functionalized with polyaniline (PANI) polymer, then C2H5OH-SiO2/PANI (CSP) was synthesized by dispersion process in ultrasound sonication by ethanol solution. CSP were successfully synthesized and determined by several characterizations such as FTIR, SEM, TEM and BET. Based on the practical data, the Cd(II) adsorption was followed by Langmuir adsorption isotherms, and the pseudo-second order adsorption kinetic. CSP has obtained the Cd maximum adsorption capacity of 301.23 mg g-1, which is higher than the previous reported adsorbents. Cd(II) adsorption by CSP is desired at pH 6, reaction time of 150 min, initial concentration at 300 mg L-1, and weight of 0.6 g. Adsorption data show that pH is one of the most important factor in Cd(II) adsorption due to the formation of surface complexes between Cd2+ and the functional groups of CSP such as hydroxyl group (OH-), silanol (Si-OH), amine (–NH2), quinoid imine [C=N–] and benzenoid amine [–NH–].

A metabolomics approach to evaluate post‐fermentation enhancement of daidzein and genistein in a green okara extract

Okara is a major agri-industrial by-product of the tofu and soymilk industries. Employing food-wastes as substrates for the green production of natural functional compounds is a recent trend that addresses the dual concepts of sustainable production and a zero-waste ecosystem. Extracts of unfermented okara and okara fermented with Rhizopus oligosporus were obtained using ethanol as extraction solvent, coupled with ultrasound sonication for enhanced extraction. Fermented extracts yielded significantly better results for total phenolic content (TPC) and total flavonoid content (TFC) than unfermented extracts. A qualitative liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) analysis revealed a shift from glucoside forms to respective aglycone forms of the detected isoflavones, post-fermentation. Since the aglycone forms have been associated with numerous health benefits, a quantitative high-performance liquid chromatography (HPLC) analysis was performed. Fermented okara extracts had daidzein and genistein concentrations of 11.782 ± 0.325 μg mL-1 and 10.125 ± 1.028 μg mL-1 , as opposed to that of 6.7 ± 2.42 μg mL-1 and 4.55 ± 0.316 μg mL-1 in raw okara extracts, respectively. Lastly, the detected isoflavones were mapped to their metabolic pathways, to understand the biochemical reactions triggered during the fermentation process. Fermented okara may be implemented as a sustainable solution for production of natural bioactive isoflavonoids genistein and daidzein. © 2021 Society of Chemical Industry.

Cu-Catalyzed Atom Transfer Radical Polymerization in the Presence of Liquid Metal Micro/Nanodroplets

Micro/nanodroplets of the liquid metal (LM) eutectic Ga–In alloy (EGaIn) were employed in atom transfer radical polymerization (ATRP) in organic solvents with low ppm (parts per million) loading of Cu catalysts. ATRP in the presence of EGaIn produced well-defined polymers (dispersity <1.1) that could be easily separated from EGaIn via centrifugation. Voltammetric analysis revealed that EGaIn micro/nanodroplets reduced CuII complexes to CuI complexes, which acted as ATRP activators. A key distinction from previously reported LM-mediated radical polymerizations is that this process did not require external forces, such as ultrasound sonication. EGaIn droplets also activated dormant alkyl bromide species. However, this reaction was ∼6 orders of magnitude slower than the corresponding activation by CuI complexes, resembling SARA (supplemental activators and reducing agents) ATRP.

Focused Ultrasound-Enhanced Delivery of Intranasally Administered Anti-Programmed Cell Death-Ligand 1 Antibody to an Intracranial Murine Glioma Model.

Immune checkpoint inhibitors have great potential for the treatment of gliomas; however, their therapeutic efficacy has been partially limited by their inability to efficiently cross the blood–brain barrier (BBB). The objective of this study was to evaluate the capability of focused-ultrasound-mediated intranasal brain drug delivery (FUSIN) in achieving the locally enhanced delivery of anti-programmed cell death-ligand 1 antibody (aPD-L1) to the brain. Both non-tumor mice and mice transcranially implanted with GL261 glioma cells at the brainstem were used in this study. aPD-L1 was labeled with a near-infrared fluorescence dye (IRDye 800CW) and administered to mice through the nasal route to the brain, followed by focused ultrasound sonication in the presence of systemically injected microbubbles. FUSIN enhanced the accumulation of aPD-L1 at the FUS-targeted brainstem by an average of 4.03- and 3.74-fold compared with intranasal (IN) administration alone in the non-tumor mice and glioma mice, respectively. Immunohistochemistry staining found that aPD-L1 was mainly located within the perivascular spaces after IN delivery, while FUSIN further enhanced the penetration depth and delivery efficiency of aPD-L1 to the brain parenchyma. The delivered aPD-L1 was found to be colocalized with the tumor cells after FUSIN delivery to the brainstem glioma. These findings suggest that FUSIN is a promising technique to enhance the delivery of immune checkpoint inhibitors to gliomas.

Safety and Efficacy of Magnetic Resonance-Guided Focused Ultrasound Surgery With Autofocusing Echo Imaging.

ObjectiveMagnetic resonance-guided focused ultrasound surgery (MRgFUS) lesioning is a new treatment for brain disorders. However, the skull is a major barrier of ultrasound sonication in MRgFUS because it has an irregular surface and varies its size and shape among individuals. We recently developed the concept of skull density ratio (SDR) to select candidates for MRgFUS from among patients with essential tremor (ET). However, SDR is not the only factor contributing to successful MRgFUS lesioning treatment—refining the target through exact measurement of the ultrasonic echo in the transducer also improves treatment efficacy. In the present study, we carried out MRgFUS lesioning using an autofocusing echo imaging technique. We aimed to evaluate the safety and efficacy of this new approach, especially in patients with low SDR in whom previous focusing methods have failed.MethodsFrom December 2019 to March 2020, we recruited 10 patients with ET or Parkinson’s disease (PD) who had a low SDR. Two patients dropped out of the trial due to the screening failure of other medical diseases. In total, eight patients were included: six with ET who underwent MRgFUS thalamotomy and two with PD who underwent MRgFUS pallidotomy. The autofocusing echo imaging technique was used in all cases.ResultsThe mean SDR of the patients with ET was 0.34 (range: 0.29–0.39), while that of the patients with PD was 0.41 (range: 0.38–0.44). The mean skull volume of patients with ET was 280.57 cm3 (range: 227–319 cm3), while that of the patients with PD was 287.13 cm3 (range: 271–303 cm3). During MRgFUS, a mean of 15 sonications were performed, among which a mean of 5.63 used the autofocusing technique. The mean maximal temperature (Tmax) achieved was 55.88°C (range: 52–59°C), while the mean energy delivered was 34.75 kJ (range: 20–42 kJ) among all patients. No serious adverse events occurred during or after treatment. Tmax or sonication factors (skull volume, SDR, sonication number, autofocusing score, similarity score, energy range, and power) were not correlated with autofocusing technique (p > 0.05, autofocusing score showed a p-value of 0.071).ConclusionUsing autofocusing echo imaging lesioning, a safe and efficient MRgFUS treatment, is available even for patients with a low SDR. Therefore, the indications for MRgFUS lesioning could be expanded to include patients with ET who have an SDR < 0.4 and those with PD who have an SDR < 0.45.Clinical Trial Registrationclinicaltrials.gov, identifier: NCT03935581.

Piezotronics boosted plasmonic localization and hot electron injection of coralline-like Ag/BaTiO3 nanoarrays for photocatalytic application

Coralline-like Ag/BaTiO3 nanoarrays have been synthesized on Ti wafer to enhance the photocatalytic performances under ultrasound sonication, and the LSPR-BaTiO3 piezo-photocatalysis mechanism is firstly investigated by numerical analysis.

Development of inhalable cubosome nanoparticles of Nystatin for effective management of Invasive Pulmonary Aspergillosis

Background and Aims: Invasive pulmonary aspergillosis (IPA) is an imperative concern in the present era due to its high occurrence and mortality rate in severely immunocompromised patients. The present study was designed to develop, optimize and characterize encapsulated nystatin (NYS) cubosome nanoparticles as an inhalable system, a viable alternative for effective management of IPA. Methods: A dry lipidic film comprising glycerol monooleate (GMO), Span 83, Poloxamer (P-407) and dispersed NYS was subjected to ultrasound sonication to produce colloidal dispersion of cubosomes. The process and formulation variables were screened using Plackett Burman design and further optimized by Box Behnken design by evaluating its effect on particle size, polydispersity index (PDI), zeta potential and entrapment efficiency. Results: The optimized NYS cubosomes were nearly spherical with some irregular polyangular symmetry as visualized by transmission electron microscopy (TEM). Further, small angle X-ray scattering (SAXS) affirmed Pn3m cubic mesophasic structure. The optimized nanoparticles had particle size 263.5 nm, zeta potential -14.4 mV, PDI 0.283 and entrapment efficiency 82%. The in-vitro cytotoxicity assay indicated that NYS cubosomes reduced cell cytotoxicity in contrast to pure drug post 48h. In-vitro haemolytic assay denoted lower toxicity of formulation as compared to free drug. In-vitro drug release studies highlighted, slow but continuous release from NYS cubosomes until 48h and showcased Higuchi release kinetics. Likewise, NYS cubosome demonstrated higher antifungal activity compared to drug suspended in phosphate buffer. Conclusion: Thus, non-invasive feature and contemplated target specificity of nystatin loaded cubosome nanoparticles pave a mode for its prospect as pulmonary delivery to combat IPA.

Reusable Surface-Enhanced Raman Spectroscopy Membranes and Textiles via Template-Assisted Self-Assembly and Micro/Nanoimprinting.

Surface-enhanced Raman spectroscopy (SERS) has emerged as a powerful tool for ultrasensitive fingerprint recognition of molecules with considerable potential in wearable biochemical sensing. However, previous efforts to fabricate wearable SERS devices by directly treating fabrics with plasmonic nanoparticles have generated a nonuniform assembly of nanoparticles, weakly adsorbed on fabrics via van der Waals forces. Here, we report the creation of washing reusable SERS membranes and textiles via template-assisted self-assembly and micro/nanoimprinting approaches. Uniquely, we employ the capillary force driven self-assembly process to generate micropatch arrays of Au nanoparticle (NP) aggregates within hydrophobic microstructured templates, which are then robustly bonded onto semipermeable transparent membranes and stretchable textiles using the UV-resist based micro/nanoimprinting technique. A mild reactive ion etching (RIE) treatment of SERS membranes and textiles can physically expose the SERS hotspots of Au NP-aggregates embedded within the polymer UV resist for further improvement of their SERS performance. Also, we demonstrate that the semipermeable transparent SERS membranes can keep the moisture content of meat from evaporating to enable stable in situ SERS monitoring of biochemical environments at the fresh meat surface. By contrast, stretchable SERS textiles can allow the spreading, soaking, and evaporation of solution analyte samples on the fabric matrix for continuous enrichment of analyte molecules at the hotspots in biochemical SERS detection. Due to the mechanical robustness of the UV-resist immobilized Au NP aggregates, simple detergent-water washing with ultrasound sonication or mechanical stirring can noninvasively clean contaminated hot spots to reuse SERS textiles. Therefore, we envision that washing reusable SERS membranes and textiles by template-assisted self-assembly and micro/nanoimprinting fabrication are promising for wearable biochemical sensing applications, such as wound monitoring and body fluid monitoring.

Pressurized hot water crosslinking of gelatin-alginate for the enhancement of spent coffee oil emulsion stability

In this study, subcritical water was used to crosslink gelatin and alginate (G/A) at different temperatures (120 °C, 130 °C, 140 °C, 150 °C, and 160 °C) under constant pressure and reaction time (3 MPa, 30 min). Structural and morphological characterization was performed using Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), nuclear magnetic resonance spectroscopy (1H NMR), and scanning electron microscopy (SEM). The coffee oil-filled hydrogels were prepared using G/A blend by ultrasound sonication. The emulsions revealed a unimodal distribution of particles with varying diameters (654 ± 98) nm, (509 ± 44) nm, and (412 ± 68) nm for G/A at 120 °C, 130 °C and 140 °C, respectively. However, the treatment of G/A at 150 °C and 160 °C resulted in bimodal size distribution and declined viscosity, and indicated the molecular degradation of hydrogels leading to weak repulsion force against droplet aggregation. Highly stable emulsions were observed from G/A at (120–140) °C, while at 150 °C and 160 °C, the emulsion exhibited poor stability during 7 weeks of storage at 5 °C and 25 °C.