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Production of Essential Oils
Published in K. Hüsnü Can Başer, Gerhard Buchbauer, Handbook of Essential Oils, 2020
Raw materials occurring in the form of hard grains have to be comminuted, for example, ground up before water distillation. This is carried out in the presence of water, such as in a wet-grinding turbine, and the water is used later during the distillation. The stills themselves are equipped with blade stirrers ensuring thorough mixing and particularly dislodging oil particles or biomass articles sticking to the walls of the still, the consequence of which can be burning and burnt notes. Dry grinding is likely to result in a significant loss of volatiles. Pepper, coriander, cardamom, celery seed, and angelica seed as well as roots, cumin, caraway, and many other seeds and fruits are treated in this manner. The process used in all these cases is called “turbo distillation.” The ratio oil/condensate is very low when this method is used, and it is for that reason that turbo distillation uses a fractionating column to enrich the volatiles. This also assists in preventing small particles of biomass passing into the condenser and contaminating the oil. As in many other distillation and rectification units, cold traps are installed to capture any very volatile oil constituents that may be present. This water-distillation procedure is also used for gums such as myrrh, olibanum, opopanax, and benzoin.
Liquid Phase Sequence Analysis of Proteins/Peptides
Published in Ajit S. Bhown, Protein/Peptide Sequence Analysis: Current Methodologies, 1988
A cold trap located between the vacuum pump and the reaction assembly used to be standard on the 890M and can be added onto the 890C without much plumbing. The cold trap acts as a barrier to prevent corrosive vapors from entering the vacuum pump, thus significantly increasing the efficiency and life of the pumps. It is, therefore, necessary that the cold trap be properly maintained. If the sequencer is used constantly, it is advisable to defrost the trap once a week and change the alcohol inside the cold trap once every 2 months. These precautions help maintain the cold trap in good working condition.
Preparation, evaluation, and in vitro cytotoxicity studies of artesunate-loaded glycyrrhetinic acid decorated PEG-PLGA nanoparticles
Published in Drug Development and Industrial Pharmacy, 2020
Xuwang Pan, Shourong Liu, Liping Ju, Jianjun Xi, Ruoyu He, Yanmei Zhao, Rangxiao Zhuang, Jinsong Huang
Five potential cryoprotectants (maltose, trehalose, mannitol, lactose, and glucose) with different concentrations (1%, 3%, 5%, 7%, and 10%) were added to NP dispersion and dissolved, respectively. Aliquots of the formulation (6 ml) were dispensed into 10 ml sample bottle. Samples were placed on the shelf of cold trap at −80 °C for at least 24 h of pre-freezing operation. Then, the frozen samples were quickly transferred to the shelf of the vacuum freeze dryer (Labconco, Kansas City, MO) and lyophilized at −50 °C for a 48 h cycle. Freeze drying was performed on at least three independent samples of each formulation. Sample reconstitution was prepared by adding 6 ml of water to the whole content of powder in the 10 ml sample bottle with manual, moderate shaking. No sonication or mechanically assisted mixing was employed. Samples after reconstitution were analyzed in triplicate.
Cerebrospinal fluid untargeted metabolomic profiling of aneurysmal subarachnoid hemorrhage: an exploratory study
Published in British Journal of Neurosurgery, 2018
Alex Y. Lu, Eyiyemisi C. Damisah, Ethan A. Winkler, Ryan A. Grant, Tore Eid, Ketan R. Bulsara
After collection, CSF samples were immediately frozen and stored at −80 °C until simultaneous processing until crush-precipitation to extract protein and debris-free CSF22. For each sample, 5 μl of CSF were mixed with 1.0 ml of extraction solution (acetonitrile, isopropanol, and water in proportion 3:3:2). Samples were vortexed for 10 s and shook for 5 min at 4 °C using an Orbital Mixing Chilling/Heating Plate (Torrey Pines Scientific Instruments; Carlsbad, CA). Samples were then centrifuged for 2 min at 14,000 rcf. The whole aliquot was evaporated using a Centrivap cold trap concentrator (Labconco, Kansas City, MO) to complete dryness and then re-suspended with 450 μl of degassed 50% acetonitrile. After being centrifuged for 2 min at 14,000 rcf, the supernatant was removed, dried, and submitted for derivatization.
Formulation of sitagliptin-loaded oral polymeric nano scaffold: process parameters evaluation and enhanced anti-diabetic performance
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2018
Mohammed Asadullah Jahangir, Ruqaiyah Khan, Syed Sarim Imam
Nanoparticles containing sitagliptin was prepared using combined technique of solvent evaporation and nanoprecipitation technique with slight modification [11]. The formulation was done in two-step, initially; emulsification step was done between the organic polymer solution into aqueous surfactant solution. Further, in second step, evaporation of organic solvent is carried out, lead to polymer precipitation and formation of nanoparticles [29]. The calculated quantities of eudragit and tween 80 and PVA (fixed concentration) were varied according to the experimental design approach as depicted in Table 2. Eudragit was dissolved in an organic solvent acetone (10 ml) and separately tween 80 dissolved in double distilled water. The organic solvent was added slowly to the aqueous phase containing tween 80 with a constant stirring on magnetic stirrer at room temperature. The evaporation of the organic solvent was performed at a temperature range of 65–80 °C which involves precipitation process lead to formation of nanoparticles. The obtained nanoparticle was ultrasonicated for different time interval (3–7 min) at 60–80 KHz amplitude) for 1 cycle and allowed to cool at room temperature. The developed SIT-NPs were lyophilized using the freeze dryer at a chamber pressure (20 pa) and cold trap temperature (−20 °C) in the entire process. The study was performed for 24 h for freezing, 4 h for primary drying at 0 °C, followed by 10 °C for 2 h and 15 °C for 1.5 h and secondary drying at 25 °C for 3 h. Mannitol (3%) was added as a cryoprotectant to avoid lysis of NPs [26].