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Ursolic Acid: A Pentacyclic Triterpene from Plants in Nanomedicine
Published in Mahfoozur Rahman, Sarwar Beg, Mazin A. Zamzami, Hani Choudhry, Aftab Ahmad, Khalid S. Alharbi, Biomarkers as Targeted Herbal Drug Discovery, 2022
Monalisha Sen Gupta, Md. Adil Shaharyar, Mahfoozur Rahman, Kumar Anand, Imran Kazmi, Muhammad Afzal, Sanmoy Karmakar
In a search of other formulations based on nanotechnology, work by Wang et al. was found. Specifically, this research group tailored the particle size of UA nano-suspensions by using anti-solvent precipitation with a four-stream multi-inlet vortex mixer. It was observed that an increased relative amount of water to ethanol in the final mixture resulted in increased mean particle size. Mean particle sizes of 90 nm (ethanol: water volume ratio of 1:7) and 300 nm (1:15 ratio) were obtained, and the p.i. of all nano-suspensions was <0.3 (Gao et al., 2015).
Determination of Antiviral Activity
Published in Adorjan Aszalos, Modern Analysis of Antibiotics, 2020
A typical in vitro evaluation will utilize seven concentrations of test substance, beginning with a maximum level of 1000 μg/ml, and varying by one-half log dilutions through 1 μg/ml. Since our material is to be diluted 1:2 with virus when placed on cells, we begin with 2000 μg/ml. Let us assume our material is somewhat insoluble in aqueous solutions. The medium to be employed is Eagle’s minimum essential medium (MEM) supplemented with 5% fetal bovine serum, 0.18% NaHCO3, and 50 μg/ml gentamicin. Since the test substance did not readily go into solution, the mixture is vortexed using a standard vortex mixer (American Scientific Products, McGaw Park, Illinois) for 1 min. The material is then sonified using a Branson ultrasonic cleaner for an additional 10 min. In our example, some particulate material is still visible, so this is centrifuged out using low-speed centrifugation for 5 min. The supernatant is then used for our antiviral test. Included with the test will be a previously prepared known active substance; vidarabine (9-β-D-arabinofuranosyladenine) is typically used for our herpesvirus testing at an initial concentration of 2000 μg/ml.
Biochemical Methods of Studying Hepatotoxicity
Published in Robert G. Meeks, Steadman D. Harrison, Richard J. Bull, Hepatotoxicology, 2020
Prasada Rao S. Kodavanti, Harihara M. Mehendale
Add 100 μl of each standard solution (0 to 50 pmol/ml) or sample to the appropriate tubes. Maintain blank tubes by adding 200 μl of assay buffer. Add 100 μl of the working tracer solution to all tubes. Add 100 μl of antiserum complex to all tubes, except blank tubes. Mix all tubes, cover and incubate overnight (16 to 18 h) at 2 to 8°C. After incubation, add 0.5 ml of cold cAMP precipitator to all the other tubes. Mix well with a vortex mixer and centrifuge in cold for 15 min at approximately 1200 × g. Decant by gently inverting all tubes once, preferably at the same time, discarding the supernatant into a radioactive waste container. Keeping the tubes inverted, place them on absorbent paper for blotting. Allow tubes to drain for 20 to 30 s. Count all tubes in a gamma counter optimized for (125I). At the usual counting efficiency of 50 to 70%, a counting time of 1 min should be sufficient. The sample values can be obtained from standard graph and expressed as pmol/g liver.
Impact of Aluminium phthalocyanine nanoconjugate on melanoma stem cells
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2023
Bridgette Mkhobongo, Rahul Chandran, Heidi Abrahamse
Direct electrostatic contact between the Pc sulphate (S) and the NP surface results in self-assembly. Ligand exchange occurs on the NP surface as a result of direct coordination of the Pc S and/or N to the NP [43]. For Pc-NP mixing, a single solvent, such as water, was utilised. Polymer chains on the PEGylated AuNPs were attached to the S groups on the AlPcS4Cl PS using a ligand exchange method, as shown in Figure 1. A concentration of 35 µM, which was the standardised dosage for the A375 total cell population, was added to 50 ppm AuNPs (Sigma-Aldrich, 765465) in Eppendorf® LoBind microcentrifuge tubes (Sigma-Aldrich, Z666556). A Multifunction Vortex Mixer Set with a Microtube Platform Head (VM-10) (DAIHAN-brand®, N05042000008187) vortexed the mixture at room temperature overnight at high speed, avoiding subjection to light. Repetitive centrifugation for 1 h at 18,000 rpm (HeraeusTM FrescoTM 17 Microcentrifuge, Thermo ScientificTM, 75002402) was used to purify the mixture. After removing the supernatant, the product was resuspended and centrifuged again to extract all unbound PS.
Preparation and characterisation of self-emulsifying drug delivery system (SEDDS) for enhancing oral bioavailability of metformin hydrochloride using hydrophobic ion pairing complexation
Published in Journal of Microencapsulation, 2023
Seyedeh Nika Rezvanjou, Mohammad Reza Niavand, Omid Heydari Shayesteh, Ehsan Mehrani Yeganeh, Davood Ahmadi Moghadam, Katayoun Derakhshandeh, Reza Mahjub
For preparation of SEDDS prototypes, metformin and SLS in weight ratio 1:4 were both dissolved in SIF. The amount of metformin was kept constant in all formulations. After complete dissolution and for better electrostatic interactions, the pH was adjusted to 3.3 using diluted acetic acid, and the translucent solution was additionally stirred for 30 min. Then after, liquid paraffin, in various amounts, was added to the prepared complexes. After vigorous mixing for 20 min, the oil phase was collected for further processing while the aqueous phase was used to determine the amount of un-recovered metformin complexes using HPLC. Then, various amounts of tween 80 and propylene glycol were added separately to the obtained liquid paraffin containing metformin ion paired hydrophobic complexes. The mixture was shaken vigorously using a vortex mixer to obtain a homogeneous liquid. As no sign of precipitation was visually observed after mixing, the complete dissolution of the component was ascertained. For fabrication of the SEDDS, the prepared prototypes were diluted with ratio of 1:100 using preheated SIF medium at constant temperature of 37ºC. The mixtures were finally stirred for various time intervals designated as the time of stirring to produce SEDDS.
Management of recurrent aphthous ulcers exploiting polymer-based Muco-adhesive sponges: in-vitro and in-vivo evaluation
Published in Drug Delivery, 2021
Muhammed Ossama, Caroline Lamie, Mohamed Tarek, Hebatallah A. Wagdy, Dalia A. Attia, Mohamed M. Elmazar
The ultra-performance liquid chromatography (UPLC) system utilized in this work was Thermo Fisher UHPLC Dionex Ultimate 3000 (Germering, Germany). The system consists of a pump (ISO-3100SD), autosampler (WPS 3000SL) and column thermostat (TCC-3000 SD). The detector was a Diode Array detector (DAD-3000 RS) (Germering, Germany). For data acquisition, the software utilized was Chromeleon 6.8 (Germering, Germany). The separation was carried out using AcclaimTM RSLC 120 C18 column 2.2 μm (2.1 × 100 mm), Thermo Fisher. The pH of the buffer was adjusted using Jenway pH-meter3310, Dunmow, Essex, United Kingdom. MilliQ water was prepared using a water purification system (Thermo scientific Barnstead Smart2Pure 3 UV, Hungary). For the degassing of the mobile phase and also to facilitate the drug extraction, an ultrasonicator (Elmasonic S60 h, Germany) was utilized. The dosage form vortexed by vortex mixer VelpScientifica, Europe.