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1.
Int J Mol Sci ; 25(14)2024 Jul 14.
Article in English | MEDLINE | ID: mdl-39062951

ABSTRACT

Rosemary has many medicinal and therapeutic properties and therefore it is important to study how to maximize the recovery of its bioactive compounds. In the present study, four different extraction techniques were used, namely stirring extraction (STE), pulsed electric field-assisted extraction (PEF), ultrasound probe-assisted extraction (UPAE), and ultrasound bath-assisted extraction (UBAE). First, some primary experiments were carried out in order to optimize each technique individually through the Plackett-Burman design. Then, each technique was applied under optimal conditions and the results were compared with each other. The optimal total polyphenol content (TPC) of STE is ~19 mg gallic acid equivalents per gram of dry weight (dw), while the antioxidant activity of the extract is 162 µmol ascorbic acid equivalents (AAEs) per gram of dw via FRAP and ~110 µmol AAE per gram of dw via DPPH. As for PEF, the optimal TPC is ~12 mg GAE/g dw, and the FRAP and DPPH values are ~102 and ~70 µmol AAE per gram of dw, respectively. When it comes to UPAE, the optimal TPC is ~16 mg GAE/g dw and the antioxidant capacity of the extract is ~128 µmol AAE/g dw through FRAP and ~98 µmol AAE/g dw through DPPH. UBAE optimal extract yielded ~17 mg GAE/g dw TPC, ~146 µmol AAE/g dw for FRAP, and ~143 µmol AAE/g dw for DPPH. The highest flavonoid content (~6.5 mg rutin equivalent/g dw) and DPPH (~143 µmol ascorbic acid equivalent/g dw) is obtained through UBAE. UPAE has been shown to be more efficient in recovering ascorbic acid (~20 mg/g dw). Additionally, the chlorophyll-to-carotenoid ratios of UPAE and UBAE were 2.98 and 2.96, respectively, indicating that the extracts had a generally positive impact on health. Considering the environmental impact of each extraction technique but also which antioxidant factor needs to be maximized, the most suitable extraction technique will be chosen.


Subject(s)
Antioxidants , Plant Extracts , Rosmarinus , Antioxidants/chemistry , Antioxidants/isolation & purification , Rosmarinus/chemistry , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Polyphenols/isolation & purification , Polyphenols/chemistry , Polyphenols/analysis , Chemical Fractionation/methods , Ascorbic Acid/chemistry , Ascorbic Acid/analysis
2.
Beijing Da Xue Xue Bao Yi Xue Ban ; 56(4): 605-609, 2024 Aug 18.
Article in Chinese | MEDLINE | ID: mdl-39041553

ABSTRACT

OBJECTIVE: To investigate the efficacy and safety of mini-track, mini-nephroscopy and mini-ultrasonic probe percutaneous nephrolithotomy (3mPCNL) for the treatment of 1.5-2.5 cm kidney stones. METHODS: The perioperative data and postoperative follow-up data of a total of 25 patients with about 1.5-2.5 cm kidney stones who underwent 3mPCNL under ultrasound guidance in Peking University People's Hospital from November 2023 to January 2024 were retrospectively analyzed. During the matching period, the 25 patients with 1.5-2.5 cm kidney stones receiving standard percutaneous nephrolithotomy (sPCNL) were matched one-to-one according to the criterion that the absolute difference of the maximum diameter of stones between the two groups was less than 1 mm. The operative time, renal function changes, postoperative stone-free rate, hemoglobin changes, and complication rate of the two treatments were compared, and then the effectiveness and safety of 3mPCNL were preliminarily analyzed. RESULTS: There were no significant differences in mean age, preoperative median creatinine, preoperative mean hemoglobin, preoperative mean hematocrit, median stone maximum diameter, and median stone CT density between the 3mPCNL group and the sPCNL group. The median operation time in the 3mPCNL group was 60.0 (45.0-110.0) min, with no statistical significance compared with the sPCNL group, and all the patients underwent single-channel operations. The mean hemoglobin after operation in the 3mPCNL group was (115.3±15.5) mmol/L, and there was no significant difference between the preoperative group and the sPCNL group, and the mean hemoglobin decreased significantly between the sPCNL group and the sPCNL group [(9.5±2.2) mmol/L vs. (10.1±1.9) mmol/L]. The mean hematocrit after operation was (28.0±5.2)%, and the difference was statistically significant compared with that before operation (t=2.414, P=0.020). The mean hematocrit drop was not statistically signi-ficant compared with the sPCNL group (2.3% vs. 2.7%). The median serum creatinine in the 3mPCNL group was 74.0 (51.0-118.0) µmol/L after operation, and the difference was statistically significant compared with that before operation (Z=-2.980, P=0.005). The stone-free rate in the 3mPCNL group and the sPCNL group was 96.0% and 97.3%, respectively, and the mean hospital stay was (4.3± 1.4) d and (5.5±2.0) d, respectively, with the statistical significance (t=0.192, P=0.025). After the operation, one patient in sPCNL group had massive hemorrhage after the nephrostomy tube was removed, which was improved after selective renal artery embolization. One patient in the 3mPCNL group developed mild perirenal hematoma, which was improved after conservative treatment, and no complications were observed in the other patients. CONCLUSION: 3mPCNL in the treatment of 1.5-2.5 cm kidney stones can achieve an effective rate comparable to sPCNL, and can achieve the ideal stone-free rate in a shorter operative time with a lower rate of surgery-related complications.


Subject(s)
Kidney Calculi , Nephrolithotomy, Percutaneous , Humans , Kidney Calculi/surgery , Nephrolithotomy, Percutaneous/methods , Nephrolithotomy, Percutaneous/adverse effects , Retrospective Studies , Treatment Outcome , Operative Time , Male , Female , Middle Aged
3.
Urolithiasis ; 51(1): 114, 2023 Sep 20.
Article in English | MEDLINE | ID: mdl-37728800

ABSTRACT

In the extracorporeal shock wave lithotripsy for infants, we used a medical polymer gel pad to assist ultrasonic positioning, so that the ultrasonic probe could be far away from the shock wave energy field. Although not affecting the ultrasonic positioning and monitoring effect, we discussed the protective effect of this method on the ultrasonic probe. A retrospective analysis was made on 21 infants (0-3 years old) who received ESWL in our hospital from June 2021 to February 2023. After the stones were accurately located by B-ultrasound before surgery, a 4 * 5 * 10 cm medical polymer gel pad was placed between the skin and the ultrasonic probe to keep the ultrasonic probe away from the shock wave energy field. The B-ultrasonic wave source locked the target stone through the gel pad, and the lithotripter Dornier Compact Delta II was used for lithotripsy. The extracorporeal shock wave lithotripsy was completed under the whole process of B-ultrasonic monitoring. All patients completed the surgery under ultrasound monitoring, and there were no abnormalities in the ultrasound probe during the surgery. The average stone size was 0.60 ± 0.21 cm, the surgical time was 39.8 ± 13.8 min, and the total energy of lithotripsy was 7.41 ± 4.35 J. There were no obvious complications in all patients after the surgery. After 2 weeks of ultrasound examination, the success rate of lithotripsy in 21 patients reached 85.7%. We believe that the use of the gel pad increases the distance between the ultrasonic probe and the skin, leaving the probe away from the shock wave energy field, avoiding the damage of the shock wave source to the ultrasonic probe, and does not affect the monitoring effect of ultrasound on stones and the success rate of lithotripsy, which is worthy of further promotion in the field of children's urinary stones.


Subject(s)
Lithotripsy , Urinary Calculi , Urolithiasis , Child , Humans , Infant , Infant, Newborn , Child, Preschool , Retrospective Studies , Lithotripsy/adverse effects , Polymers
4.
Plants (Basel) ; 12(12)2023 Jun 19.
Article in English | MEDLINE | ID: mdl-37376004

ABSTRACT

The caper bush has developed different mechanisms to survive in Mediterranean conditions, such as drought tolerance and seed dormancy. Many studies have been carried out to improve the germination of caper seeds, but ultrasound is one of the least studied methodologies in this species. This study aimed to analyze the effects of treatments with an ultrasonic probe processor on the imbibition and germination of caper seeds. After applying the ultrasound treatment using three output powers and three holding times, the seed coat's disruption level was determined, and the imbibition, viability and germination tests were carried out. Ultrasonication fastens the initial imbibition, but after 48 h of soaking, seed moisture does not present differences compared to non-sonicated seeds. It produces the scarification of the testa but does not affect the tegmen, so moistening occurs through the hilar region, as in control seeds. There is a significant linear and negative correlation between the germination of the seeds and the temperature reached during the sonication treatment, so that temperatures above 40 °C practically annulled the germination. The combination of 20 W and 60 s provided the greatest germination percentage, being the only treatment that statistically improves germination in relation to the control seeds. When the output power and/or holding time were higher, the temperature increased, and the germination percentage statistically decreased.

5.
BMC Urol ; 22(1): 144, 2022 Sep 07.
Article in English | MEDLINE | ID: mdl-36071397

ABSTRACT

BACKGROUND: To assess the outcome of the mini-track, mini-nephroscopy, mini ultrasonic probe percutaneous nephrolithotomy for upper ureteral and kidney stones. METHODS: We collected data of 53 patients (55 kidney units) who underwent mini-track, mini-nephroscopy, mini-ultrasonic probe percutaneous nephrolithotomy between September 2020 and March 2021. The study included single and upper ureteral stones from 12 kidneys, multiple stones from 28 kidneys, and staghorn stones from 15 kidneys. RESULTS: The mean operative duration was 50.6 min, ranging from 15 to 200 min, whereas the mean lithotripsy and stone removal time was 17.2 min (3-45 min). Moreover, the mean postoperative length of stay was 4.0 days (1-7 days). Besides, the stone-free rate (SFR) of discharge was 89.1% (49/55). The mean hemoglobin drop was 15.3 mg/dL, ranging 1-32 mg/dL. Out of the total cases, only 4 of them displayed minor complications. The outcomes of < 40 mm versus ≥ 40 mm calculi were compared by performing subgroup analysis. The results demonstrated a longer operation duration (65.2 vs. 40.2 min), higher complication rate (13.0% vs. 3.3%), and lower SFR in the ≥ 40 mm calculi subgroup. CONCLUSIONS: In summary, mini-track, mini-nephroscopy, mini-ultrasonic probe percutaneous nephrolithotomy is an effective and safe method to treat patients with upper ureteral and kidney calculi. This is especially significant for the stone size of 20-40 mm, demonstrating excellent SFR and a lower complication rate.


Subject(s)
Kidney Calculi , Nephrolithotomy, Percutaneous , Nephrostomy, Percutaneous , Ureteral Calculi , Humans , Kidney , Kidney Calculi/diagnostic imaging , Kidney Calculi/surgery , Nephrolithotomy, Percutaneous/methods , Nephrostomy, Percutaneous/methods , Retrospective Studies , Treatment Outcome , Ultrasonics , Ureteral Calculi/surgery
6.
Sensors (Basel) ; 21(4)2021 Feb 12.
Article in English | MEDLINE | ID: mdl-33673392

ABSTRACT

Selecting and designing the optimum ultrasonic probe is vital for ultrasonic measurements and experiments. The amplitude of the emitted ultrasonic wave excitation signal as well as the diameter and the natural frequency of the probe seriously affect the validity of the probe results. In this paper, we analyze the significance of the key parameters of the ultrasonic probe theoretically. Further, an external fixed-point liquid level monitoring system was assembled according to the principle of ultrasonic reflection and transmission. On this experimental platform, we study the key parameters of the ultrasonic probe that affect the system evaluation through a simulation and experiment, and select the optimal sensor parameters for this experiment. The evaluations show that under the experimental conditions where the tested container is made of aluminum alloy and its wall thickness is 3 mm, the best results are obtained when the diameter of the ultrasonic sensor is 15 mm, the amplitude of the emitted excitation signal is ±15 V, and the frequency is 1 MHz. The results' average deviation is less than ±0.22 V. The evaluations are consistent with the simulation results. This research can effectively monitor the liquid in the closed, ultra-thin-walled container, and can realize non-contact measurement. It provides an effective basis for the parameters selection and design of the ultrasonic probe in the ultrasonic-based experiments and tests.

7.
Int J Biol Macromol ; 170: 810-819, 2021 Feb 15.
Article in English | MEDLINE | ID: mdl-33385457

ABSTRACT

The quality of green coffee beans (GCBs) is possibly affected by storage conditions. Edible polymer coatings for GCBs can help preserve flavors and improve shelf life of GCBs. This study aimed to incorporate α-tocopherol, a powerful antioxidant, in thermoplastic starch [TPS] and chitosan [TPC] and determined the best cavitation energy (960-3840 J·mL-1) using an ultrasonic probe. Then, we evaluated the incorporation of bentonite (0% and 2% m/m) and α-tocopherol (0% and 10% m/m) in the best energy cavitation/biopolymer combination. The TPS and TPC coatings demonstrated good adherence to the GCBs, measured by surface energy. The dispersion of α-tocopherol in TPC, with cavitation energy 960 J·mL-1, promoted greater stability (greater zeta potential), thereby increasing antioxidant activity by 28% compared to TPS, therefore, was selected for a second stage. Incorporation of 2% bentonite into the TPC, with 10% α-tocopherol, resulted in a 3.7 × 10-10 g·m-1·s-1·Pa-1 water vapor permeability, which is satisfactory for prevented of moisture gain during storage. The compressive load showed values of 375 N to the non-coated GCB and around 475 N with the insertion of coatings to the GCB. Thus, a TPC/α-tocopherol/bentonite combination, dispersed with 960 J·mL-1 energy, was highly effective in the development of biopolymeric coatings for the GCBs.


Subject(s)
Bentonite , Chitosan , Coffee , Starch , alpha-Tocopherol , alpha-Tocopherol/chemistry , Antioxidants/chemistry , Bentonite/chemistry , Chitosan/chemistry , Coffee/chemistry , Food Preservation/methods , Starch/chemistry , Steam
8.
Sensors (Basel) ; 20(4)2020 Feb 21.
Article in English | MEDLINE | ID: mdl-32098102

ABSTRACT

This study presents an improved strategy for the detection and localization of small size nodules (down to few mm) of agar in excised pork liver tissues via pulse-echo ultrasound measurements performed with a 16 MHz needle probe. This work contributes to the development of a new generation of medical instruments to support robotic surgery decision processes that need information about cancerous tissues in a short time (minutes). The developed ultrasonic probe is part of a scanning platform designed for the automation of surgery-associated histological analyses. It was coupled with a force sensor to control the indentation of tissue samples placed on a steel plate. For the detection of nodules, we took advantage of the property of nodules of altering not only the acoustical properties of tissues producing ultrasound attenuation, but also of developing patterns at their boundary that can modify the shape and the amplitude of the received echo signals from the steel plate supporting the tissues. Besides the Correlation Index Amplitude (CIA), which is linked to the overall amplitude changes of the ultrasonic signals, we introduced the Correlation Index Shape (CIS) linked to their shape changes. Furthermore, we applied AND-OR logical operators to these correlation indices. The results were found particularly helpful in the localization of the irregular masses of agar we inserted into some excised liver tissues, and in the individuation of the regions of major interest over which perform the vertical dissections of tissues in an automated analysis finalized to histopathology. We correctly identified up to 89% of inclusions, with an improvement of about 14% with respect to the result obtained (78%) from the analysis performed with the CIA parameter only.


Subject(s)
Liver/pathology , Liver/surgery , Robotic Surgical Procedures/methods , Animals , Humans , Swine
9.
Ultrason Sonochem ; 62: 104876, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31796331

ABSTRACT

Phenolic acids of oak gall were extracted using ultrasonic-probe assisted extraction (UPAE) method in the presence of ionic liquid. It was compared with classical ultrasonic-bath assisted extraction (CUBAE) and conventional aqueous extraction (CAE) method, with and without the presence of ionic liquid. Remarkably, the UPAE method yielded two-fold higher extraction yield with the presence of ionic liquid, resulting 481.04 mg/g for gallic acids (GA) and 2287.90 mg/g for tannic acids (TA), while a decreased value of 130.36 mg/g for GA and 1556.26 mg/g for TA were resulted with the absence of ionic liquid. Intensification process resulted the highest yield of 497.34 mg/g and 2430.48 mg/g for GA and TA, respectively, extracted at temperature 50 °C with sonication intensity of 8.66 W/cm2 and 10% duty cycle, diluted in ionic liquid, 1-Butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, [Bmim][Tf2N] at concentration of 0.10 M with sample-to-solvent ratio 1:10 for 8 h. Peleg's model successfully predicted the UPAE process confirming that extraction capacity is the controlling factor in extracting phenolic acids. Hence, it can be concluded that UPAE method and ionic liquid have synergistic effect as it effectively enhanced the extraction efficiency to increase the bioactive constituents yield.


Subject(s)
Hydroxybenzoates/isolation & purification , Ionic Liquids/chemistry , Quercus/chemistry , Sonication , Kinetics , Microscopy, Electron, Scanning , Solvents/chemistry , Spectroscopy, Fourier Transform Infrared
10.
Ultrason Sonochem ; 59: 104725, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31442771

ABSTRACT

In this study, the effects of both ultrasonic bath and probe treatments on the phenolic, chromatic and aroma composition of young red wine Cabernet Sauvignon were studied and modeled by artificial neural networks (ANNs). Moreover, the effect of high power ultrasound (HPU) along with antioxidants addition (sulfur dioxide and glutathione) was investigated during 6 months of aging in bottles. Lower amplitude and temperature, shorter treatment duration and particularly lower frequency showed a more favorable and milder effect on the chemical composition of wine. In the case of the ultrasonic probe treatment, similar effect was achieved primarily by a larger probe diameter as well as lower amplitude and treatment duration. Selected ANN models showed the best predictions for the chromatic characteristics followed by total phenolics and anthocyanins. The changes induced by HPU treatment after 6 months of aging were mainly detected in the composition of phenolic compounds (both total and individual), where higher concentration of antioxidants (sulfur dioxide and glutathione) slowed down the decrease rate of these compounds during aging. However, HPU treatment did not influence most of the chromatic characteristics and aroma compounds, except lightness and fatty acids. The obtained results indicated that suitable ultrasound treatment might accelerate some aging reactions and shorten the period of wine aging.

11.
Int J Artif Organs ; 42(10): 586-594, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31204554

ABSTRACT

One of the main challenges of the interface-tissue engineering is the regeneration of diseased or damaged interfacial native tissues that are heterogeneous both in composition and in structure. In order to achieve this objective, innovative fabrication techniques have to be investigated. This work describes the design, fabrication, and validation of a novel mixing system to be integrated into a double-extruder bioprinter, based on an ultrasonic probe included into a mixing chamber. To validate the quality and the influence of mixing time, different nanohydroxyapatite-gelatin samples were printed. Mechanical characterization, micro-computed tomography, and thermogravimetric analysis were carried out. Samples obtained from three-dimensional bioprinting using the mixing chamber were compared to samples obtained by deposition of the same final solution obtained by manually operated ultrasound probe, showing no statistical differences. Results obtained from samples characterization allow to consider the proposed mixing system as a promising tool for the fabrication of graduated structures which are increasingly being used in interface-tissue engineering.


Subject(s)
Bioprinting , Tissue Engineering/methods , Tissue Scaffolds , Ultrasonics , Durapatite , Gelatin , Humans , Printing, Three-Dimensional , X-Ray Microtomography
12.
Anal Chim Acta ; 1018: 16-25, 2018 Aug 14.
Article in English | MEDLINE | ID: mdl-29605130

ABSTRACT

Applicability of single-particle inductively coupled plasma mass spectrometry (sp-ICP-MS) using dwell times equal to or shorter than 100 µs has been tested for assessing titanium dioxide nanoparticles (TiO2 NPs) in bivalve mollusks. TiO2 NPs isolation from fresh mollusk tissues was achieved by ultrasound assisted enzymatic hydrolysis procedure using a pancreatin/lipase mixture. Optimum extraction conditions imply ultrasonication (60% amplitude) for 10 min, and 7.5 mL of a solution containing 3.0 g L-1of pancreatin and lipase (pH 7.4). The developed method was found to be repeatable (repeatability of 17% for the over-all procedure, TiO2 NPs concentration of 5.33 × 107 ±â€¯8.89 × 106, n = 11), showing a limit of detection of 5.28 × 106 NPs g-1, and a limit of detection in size of 24.4-30.4 nm, based on the 3σ criteria, and on the 3σ/5 σ criteria, respectively. The analytical recovery within the 90-99% range (use of TiO2 NPs standards of 50 nm at 7 and 14 µg L-1 as Ti). Several bivalve mollusks (clams, cockles, mussels, razor clams, oysters and variegated scallops) were analyzed for total titanium (ICP-MS after microwave assisted acid digestion), and for TiO2 NPs by the proposed method. TiO2 NPs concentrations were within the 2.36 × 107-1.25 × 108 NPs g-1 range, and the most frequent sizes were from 50 to 70 nm.


Subject(s)
Bivalvia/chemistry , Lipase/chemistry , Nanoparticles/chemistry , Pancreatin/chemistry , Titanium/isolation & purification , Ultrasonic Waves , Animals , Bivalvia/metabolism , Hydrolysis , Lipase/metabolism , Mass Spectrometry , Nanoparticles/metabolism , Pancreatin/metabolism , Titanium/chemistry , Titanium/metabolism
13.
Respirol Case Rep ; 6(4): e00311, 2018 05.
Article in English | MEDLINE | ID: mdl-29507726

ABSTRACT

A lesion in a 73-year-old woman that was suspected to be right lung cancer was biopsied under ultrasound-guided bronchoscopy with a guide sheath. The procedure was completed without a noticeable problem, but after 3 days, it was found that the tip of the ultrasonic probe sheath was broken and that the broken fragment was missing. Based on the concern that the fragment had been left in the lung, the patient was examined by computed tomography scan 4 days after the biopsy, and bronchoscopy was repeated 38 days after the biopsy, but no fragment was detected. These procedures and an investigation by the Olympus Corporation led to the conclusion that the fragment was not in the lung, and it was not found in a subsequent surgical specimen. Breakage of devices may occur at any time regardless of progression of fatigue (wear) with increased use, and thorough device management before, during, and after use is important.

14.
Chempluschem ; 82(5): 732-741, 2017 May.
Article in English | MEDLINE | ID: mdl-31961529

ABSTRACT

Exfoliation of lamellar materials into their corresponding layers represented a breakthrough, owing to the outstanding properties arising from the nanometric thickness confinement. Among the cleavage techniques, liquid-phase exfoliation is now on the rise because it is scalable and leads to easy-to-manipulate colloids. However, all appropriate exfoliating solvents exhibit strong polarity, which greatly restricts the scope of feasible functionalization or processing of the resulting flakes. Here, this scope is extended: nanosheets exfoliated in a polar medium are demonstrated to properly disperse in a nonpolar solvent. To that purpose, suspensions of molybdenum disulfide flakes were prepared in isopropanol/water and a phase transfer of the nanosheets to chloroform was developed by flocculation and redispersion/centrifugation sequences, without any assisting surfactant. The colloidal stability of the nanosheets in chloroform was found to be governed by their lateral dimensions and, although lower than in polar media, proved to be high enough to open the way to subsequent functionalization or processing of the flakes in nonpolar media.

15.
Talanta ; 152: 353-63, 2016 May 15.
Article in English | MEDLINE | ID: mdl-26992531

ABSTRACT

A simple and fast analytical method for the determination of fourteen perfluorinated compounds (PFCs), including three perfluoroalkylsulfonates (PFSAs), seven perfluorocarboxylic acids (PFCAs), three perfluorophosphonic acids (PFPAs) and perfluorooctanesulfonamide (PFOSA) and ten potential precursors, including four polyfluoroalkyl phosphates (PAPs), four fluorotelomer saturated acids (FTCAs) and two fluorotelomer unsaturated acids (FTUCAs) in different packaging materials was developed in the present work. In order to achieve this objective the optimization of an ultrasonic probe-assisted extraction (UPAE) method was carried out before the analysis of the target compounds by liquid-chromatography-triple quadrupole-tandem mass spectrometry (LC-QqQ-MS/MS). 7 mL of 1 % acetic acid in methanol and a 2.5-min single extraction cycle were sufficient for the extraction of all the target analytes. The optimized analytical method was validated in terms of recovery, precision and method detection limits (MDLs). Apparent recovery values after correction with the corresponding labeled standard were in the 69-103 % and 62-98 % range for samples fortified at 25 ng/g and 50 ng/g concentration levels, respectively and MDL values in the 0.6-2.2 ng/g range were obtained. The developed method was applied to the analysis of plastic (milk bottle, muffin cup, pre-cooked food wrapper and cup of coffee) and cardboard materials (microwave popcorn bag, greaseproof paper for French fries, cardboard box for pizza and cinema cardboard box for popcorn). To the best of our knowledge, this is the first method that describes the determination of fourteen PFCs and ten potential precursors in packaging materials. Moreover, 6:2 FTCA, 6:2 FTUCA and 5:3 FTCA analytes were detected for the first time in microwave popcorn bags.


Subject(s)
Chromatography, High Pressure Liquid/methods , Fluorocarbons/analysis , Fluorocarbons/chemistry , Food Packaging , Tandem Mass Spectrometry/methods , Food Contamination/analysis , Limit of Detection , Reproducibility of Results , Time Factors
16.
Bioresour Technol ; 185: 116-24, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25768413

ABSTRACT

The main drawbacks of biodiesel production are high reaction temperatures, stirring and time. These could be alleviated by aiding transesterification with alternative energy sources, i.e. ultrasound (US). In this study, biodiesel was obtained from Camelina sativa oil, aided with an ultrasonic probe (20kHz, 70% duty cycle, 50% amplitude). Design of experiments included the combination of sonication and agitation cycles, w/wo heating (50°C). To gain knowledge about the implications of the proposed methodology, conventional transesterification was optimized, resulting in higher needs on catalyst concentration and reaction time, compared to the proposed reaction. Although FAME content met EN 14103 standard, FAME yields were lower than those provided by US-assisted transesterification. Energy consumption measurements showed that ultrasound assisted transesterification required lower energy, temperature, catalyst and reaction time.


Subject(s)
Biofuels/radiation effects , Brassicaceae/chemistry , Fatty Acids/chemical synthesis , Plant Extracts/chemistry , Plant Oils/chemistry , Sonication/methods , Brassicaceae/radiation effects , Esterification/radiation effects , Fatty Acids/radiation effects , High-Energy Shock Waves , Plant Extracts/radiation effects , Plant Oils/radiation effects
17.
Chinese Pharmaceutical Journal ; (24): 2026-2033, 2014.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-860136

ABSTRACT

OBJECTIVE: To prepare ZL-004 loaded PLGA nanoparticles (ZL-004-NP) and evaluate its release characteristics in vitro and pharmacokinetics in rats. METHODS: In order to determine physico-chemical property of ZL-004, saturation-constant temperature method, potentiometric method and shake flask method were employed to obtain relative parameters, respectively. After investigating single factors, the orthogonal design was used to gain optimal formulation. Then characteristic of ZL-004-NP prepared under condition of best formulation was determined by scanning electronmicroscopy, laser particle size analyzer, dialysis method, respectively. Afterward, amounts of ZL-004 in plasma were determined under UPLC-MS/MS and relative bioavailability between ZL-004-NP and its raw material was calculated. RESULTS: The feature of ZL-004-NP met aim of experiment, which contained smooth spheres, 121.34 nm of diameter, 0.16 of PDI, 89.63% of encapsulation efficiency, 7.65% of loading drug content, sustained release about 216 h in vitro and less burst in initiate stage. In vivo, cmax of ZL-004-NP was increased robustly 1.7 times, which reached to 125 μg · L-1 and tmax was cut down rapidly from (6.47 ± 0.51) h to (4.13 ± 0.48) h, compared with crude ZL-004. Relative bioavailability between ZL-004-NP and crude ZL-004 was 200.99%, which greatly improved effect of oral absorption. CONCLUSION: ZL-004-NP might be developed to improve water-insolube nature of ZL-004, which could increase oral relative bioavailability.

18.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-855405

ABSTRACT

Objective: To study the preparation technology of glycyrrhetinic acid (GA)-tanshinone IIA (Tan IIA) compound liposomes (GT-Lip). Methods: The compound liposomes were made of soybean phosphatidylcholine (SPC) and cholesterol (Ch) by film dispersion ultrasonic probe method. Hydration temperature and ultrasonic power were optimized by single factor tests and the optimum formulation was selected by orthogonal design. The encapsulation efficiencies (EE) of GA and Tan IIA were determined by low-speed centrifugation. The particle size and Zeta potential of liposomes were detected by dynamic light scattering particle size meter. Transmission electron microscopy was used to observe morphous. Results: The optimal preparation conditions were as follows weight ratio of SPC-Ch 6:1, molar ratio of SPC-Tan IIA and SPC-GA was 30:1 and 24:1, hydration temperature 30 °C, and ultrasonic power 380 W for 5 min. Using the optimal method, the EE values of GA and Tan IIA in GT-Lip were (81.50 ± 0.76)% and (98.63 ± 0.90)% (n = 3), and the average particle size of liposomes was (120.5 ± 1.62) nm and the Zeta potential of liposomes was (-19.00 ± 0.98) mV (n = 3). Conclusion: The optimal preparation method of GT-Lip in this study is stable and feasible.

19.
J Med Ultrason (2001) ; 38(3): 119-27, 2011 Jul.
Article in English | MEDLINE | ID: mdl-27278499

ABSTRACT

PURPOSE: This paper describes an investigation into direct observation of microscopic images of tissue using a thin acoustic wave guide. METHODS: First, the characteristics of the ultrasonic wave propagated in a fused quartz fiber were measured using the reflection method in order to study the insertion loss and the frequency shift of the ultrasonic wave transmitted from the transducer. Next, a receiving transducer was placed close to the end of the fiber, and the characteristics of the ultrasonic waves propagated through the acoustic coupling medium were measured using the penetration method in order to study the insertion loss and the frequency-dependent attenuation of the penetrated waves. Finally, a C-mode image was obtained by optimizing the measuring conditions using the results of the above measurements and scanning the ultrasonic beams on a target (coin) in water. RESULTS: A reflected wave with a peak frequency of approximately 220 MHz was obtained from the end of the fiber. The transmitted ultrasonic waves propagated through the acoustic coupling medium were detected with a frequency range of approximately 125-170 MHz, and the maximum detectable distance of the waves was approximately 1.2 mm within the 100-MHz frequency range. Finally, a high-frequency C-mode image of a coin in water was obtained using a tapered fused quartz fiber. CONCLUSION: The results suggest that it is necessary to improve the signal-to-noise ratio and reduce the insertion loss in the experimental system in order to make it possible to obtain microscopic images of tissue.

20.
Sensors (Basel) ; 9(5): 3325-36, 2009.
Article in English | MEDLINE | ID: mdl-22412314

ABSTRACT

Although ultrasound cavitation must be avoided for safe diagnostic applications, the ability of ultrasound to disrupt cell membranes has taken on increasing significance as a method to facilitate drug and gene delivery. A new ultrasonic resonance driving method is introduced to penetrate rigid wall plant cells or oocytes with springy cell membranes. When a reasonable design is created, ultrasound can gather energy and increase the amplitude factor. Ultrasonic penetration enables exogenous materials to enter cells without damaging them by utilizing instant acceleration. This paper seeks to develop a miniature ultrasonic probe experiment system for cell penetration. A miniature ultrasonic probe is designed and optimized using the Precise Four Terminal Network Method and Finite Element Method (FEM) and an ultrasonic generator to drive the probe is designed. The system was able to successfully puncture a single fish cell.

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