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Asparagus Sp.: Phytochemicals and Marketed Herbal Formulations
Published in Amit Baran Sharangi, K. V. Peter, Medicinal Plants, 2023
Vikas Bajpai, Pratibha Singh, Preeti Chandra, Brijesh Kumar
The seven analytes were characterized according to their mass spectra which were performed by flow injection analysis (FIA) of the individual standard solution into the mass spectrometer to ascertain their precursor ions and select productions for MRM, respectively. The electrospray interface was used which provided good sensitivity and fragmentation. In this study, the mass spectral conditions were optimized in both positive and negative-ion with continuous polarity switching mode. On the basis of sensitivity and reproducibility of dominant ions in full-scan mass spectra, positive mode was selected for the detection of sapogenin, whereas negative mode was selected for saponin, flavonoids, and phenolic acids. DP is one of the most important mass spectrometer parameters which impact ion response. Therefore, DP was optimized in order to obtain the maximum sensitivity of [M + H]+ and [M − H]−. The most suitable CE was also determined by observing the maximal response for MS/MS monitoring of fragment ions. The ions used for quantitative analysis were selected on the basis of highest peak intensity and lowest interference. All MRM parameters were optimized to achieve the most abundant, specific, and stable MRM transitions for each compound were listed in Table 12.1.
Spray Drying and Pharmaceutical Applications
Published in Dilip M. Parikh, Handbook of Pharmaceutical Granulation Technology, 2021
Metin Çelik, Pavan Muttil, Gülşilan Binzet, Susan C. Wendell
A recent technique for atomizing the feed liquid is the use of electrospray or electrohydrodynamic sprays created by electrostatic charging. In the electrospray, an electrical potential is applied to the needle to introduce free charge at the liquid surface. The high intensity of electric current applied between the two oppositely charged electrodes of an electrospray system enables the production of droplets of narrow particle size distribution. When the electrical potential rises to kilovolts, the liquid meniscus develops into a conical shape (Taylor cone), having a highly concentrated free charge. The free charge accelerates the droplets away from the needle due to the generated electric stress. Monodispersed particles will be formed when the jet breaks into fine particles due to varicose instabilities (Figure 6.10). The requirement of solvents for feed preparation and extremely low flow rates limit the usage of electrospray atomization for food applications and commercial exploitation, respectively [6].
Current Perspectives and Methods for the Characterization of Natural Medicines
Published in Rohit Dutt, Anil K. Sharma, Raj K. Keservani, Vandana Garg, Promising Drug Molecules of Natural Origin, 2020
Muthusamy Ramesh, Arunachalam Muthuraman, Nallapilai Paramakrishnan, Balasubramanyam I. Vishwanathan
Liquid chromatography-mass spectrometry (LC-MS) identifies the drug metabolites of polar to non-polar. LC-MS separates metabolites based on polarity, molecular weight, and hydrophobicity. Two different types of basic principles were employed in LC, i.e., (i) normal liquid phase chromatography where the polar stable phase is employed; and (ii) reverse-phase liquid chromatography where non-polar stable phase is employed. Mass spec-trometry serves as a detector to identify the metabolites. Molina-Calle et al. demonstrated the characterization of Stevia leaves constituents by LC with quadrupole—a time of flight (LC-QTOF) mass spectrometry (Molina-Calle et al., 2017). Mediterranea Sea (C18) column has 5 μ m, 15 × 0.46 cm dimension and it is used in LC-MS device. The source of electrospray ionization was used in mass spectrometry. Steviol and its glycosides were determined from the analysis of polar and non-polar components of Stevia leaves. A total of eighty-one compounds of different chemical classes of flavonoids, quinic acids, caffeic acids, diterpenoids, sesquiterpenoids, amino acids, fatty acids, oligosaccharides, glycerolipids, fatty amides purines, and retinoids were identified. The study was proven to benefit the production of commercial products from Stevia (Steviarebaudiana bertoni) leaves (Molina-Calle et al., 2017). The LC-MS spectroscopy-based characterized phytoconstituents and marine compounds are listed in Table 2.2.
Electrosprayed microparticles: a novel drug delivery method
Published in Expert Opinion on Drug Delivery, 2019
Muhammet Emin Cam, Yue Zhang, Mohan Edirisinghe
The basic setup for electrospraying consists of several components: a syringe pump, a metal nozzle connected to a high voltage power source, a grounded substrate as a collector and a monitor. In order to control better the process of particle forming and facilitate the generation of smaller particles with smoother surface morphology, the electrospraying setup should be isolated in a covered chamber [3]. Basically, a stream of conductive liquid is pumped into a nozzle to which the high voltage (kV range) is applied during electrospraying to form microparticles. The principle of electrospraying is based upon the theory of charged droplets and this static charge causes an electrostatic force in the droplets [4]. Only fragments of the solution are jetted at a low voltage, creating various modes such as dripping, rapid dripping, and unstable cone-jet mode. A sustained and a continuous jet can be obtained from the balance of several forces including surface tension, gravity and electric strengths on the liquid surface; these are stable cone-jet, multi-jet and irregular unstable jet modes (Figure 1). The electrospray process is also influenced by the liquid properties including surface tension, viscosity, electrical conductivity and density as illustrated in Figure 2.
Comparison of Collection Methods for the Measure of Human Meibum and Tear Film-Derived Lipids Using Mass Spectrometry
Published in Current Eye Research, 2018
William Ngo, Jianzhong Chen, Shyam Panthi, Kelly K. Nichols, Jason J. Nichols
The uptake of meibum lipids into glass microcapillary tubes may have been facilitated by water within meibum. Since meibum consists mainly of lipids (and less water), the difference in lipid quantities between PTFE and glass microcapillaries was smaller and may have been harder to detect. It was also possible that there were larger quantities of lipids collected with both PTFE and glass microcapillaries for meibum, but ion suppression during mass spectrometry37 may have minimized the difference in intensities between the two. This effect of ion suppression may occur when analyte concentration exceeds the upper limit allowable for an electrospray event.38 The analyte saturation causes the linear response to level off and return an intensity quantity that is lower than actual.38 However, based on volume alone, there were more lipids detected by mass spectrometry from 0.19 µL of tears in PTFE than there were in 3.00 µL of tears from the glass microcapillaries (Table 1, Figure 6). This highlights the utility of PTFE for the study of lipids from the tear film using mass spectrometry.
Poly (butylene adipate-co-butylene terephthalate) nanoparticles prepared by electrospraying technique for docetaxel delivery in ovarian cancer induced mice
Published in Drug Development and Industrial Pharmacy, 2018
Jaleh Varshosaz, Erfaneh Ghassami, Abdollah Noorbakhsh, Ali Jahanian-Najafabadi, Mohsen Minaiyan, Ramezan Behzadi
Ecoflex® is a biodegradable and biocompatible polymer with a complete and relatively fast degradation and excellent flexibility. Since the initial production of Ecoflex® by BASF in 1998, this polymer has been used for packaging applications. Recently, Xinfu Pharmaceutical Co. Ltd, has paid great interest to the pharmaceutical applications of this polymer, such as production of biomedical nano-composites [13]. Considering the aforementioned advantages of this polymer, it was implicated in the current study to construct an anti-cancer drug delivery system. Some mechanical properties of Ecoflex® impose limitations on using this polymer in fabrication of therapeutic NPs by common methods. Therefore, there are just limited studies on fabrication of nanoparticles by this polymer. To overcome these limitations, electrospray method was recruited to fabricate the nanoparticles in the current study; afterwards, the in vitro and in vivo efficacy of this controlled delivery system was evaluated. To our knowledge, there is no report on the production of NPs of this polymer by electrospraying method.