Supercritical Fluid Extraction as a Sample Preparation Tool in Analytical Toxicology
Steven H. Y. Wong, Iraving Sunshine in Handbook of Analytical Therapeutic Drug Monitoring and Toxicology, 2017
Biological matrices, such as blood, urine, and tissues, generally must be desiccated and dispersed before SFE. Typically, these samples are mixed with an adsorbent such as sodium sulfate, magnesium sulfate, or Hydromatrix. There are advantages and limitations associated with the use of these adsorbents. For instance, sodium sulfate is a good desiccant; however, it may dissolve in the presence of large amounts of water. Magnesium sulfate has also been used as an SFE desiccant; however, it may bind too tightly to the sample matrix and thus restrict fluid flow. Hydromatrix, first reported as an SFE dispersing agent by Hopper and King62 in 1991, does not have these limitations. Hydromatrix is a pelletized form of diatomaceous earth that has a large surface area/volume (>200 m2/g). It reacts physically with water, rather than chemically like desiccants such as sodium sulfate. Hydromatrix is an inexpensive adsorbent, compared with some support materials, which is an important consideration when a large number of samples are routinely processed.
Laboratory coagulation assays
John Edward Boland, David W. M. Muller in Interventional Cardiology and Cardiac Catheterisation, 2019
Diatomaceous earth (Celite®) is a naturally occurring, soft, siliceous sedimentary rock. Kaolin is a hydrous aluminium silicate that is abundant in clay. Celite and kaolin are the two most common clot activating reagents used in the manufacture of ACT tests. In the presence of aprotinin (a drug used in some geographic regions to inhibit fibrinolysis during cardiopulmonary bypass procedures), ACT tests that use Celite as its primary activator have been observed to report erroneously higher than expected results. Aprotinin does not appear to have the same interfering effect on ACT tests that use kaolin as a reagent. Selection of an appropriate ACT test should consider the primary activator if aprotinin is likely to be used during patient management.
The intervention of government to provide safety standards
Dorsett D. Smith in The Health Effects of Asbestos, 2015
Fleischer and Drinker assumed that asbestosis results from breathing asbestos fibers of long length, based on Lanza’s 1935 publication. (Lanza AJ. Effects of the Inhalation of Asbestos Dust in the Lungs of Asbestos Workers. Public Health Report (vol. 50). Washington, DC: U.S. Treasury, 1935.) Fleisher and Drinker assumed that “chopped-up” asbestos, or short fibers of 1–2 μm, were inert. They concerned themselves with long fibers having a width-to-length ratio of 3 or greater, which could be seen microscopically. It was assumed that medium-length fibers would be deposited in the upper airways. According to Nowinski, a concentration of 6 mppcf of total dust would be equivalent to 0.2 mppcf of asbestos dust with a fiber length >15 μm. The authors mentioned that “petrographic analysis of asbestos cement indicate that the amount of diatomaceous earth may be as high as 87%.” The published text states 5 mppcf of “total dust” as being safe, which remains controversial in that many claim that Fleischer and Drinker meant to say “asbestos dust,” as did Dreesen. For example, Kenneth Smith, Medical Director of Johns-Manville Corp., wrote to Detroit-Edison Company in February 1959 about the health hazards of Thermobestos asbestos insulation. Smith assumed that since the product contained approximately 10% asbestos, using the American Conference of Governmental Hygienists (ACGIH) standard of 5 mppcf of asbestos dust would permit exposures to 50 mppcf of total dust. (Nowinski P. Chronology of asbestos regulation in United States workplaces. In: K Antman, J Aisner (Eds.), Asbestos-Related Malignancy. New York: Grune & Stratton, 1986, pp. 99–134.)
Integrating inert dusts with other technologies in stored products protection
Published in Toxin Reviews, 2021
Masumeh Ziaee, Asgar Ebadollahi, Waqas Wakil
Diatomaceous earth (DE) is the most widely used inert dust for stored products protection. This subsequently resulted in the production of a large number of efficacy enhanced modified DE products, the IDIs (Shah and Khan 2014). Diatomaceous earth is made up of diatoms shells that have been fossilized for centuries (Ebeling 1971). Zeolites are alkaline crystalline aluminum silicates contains SiO4 and AlO4, and due to the natural silica content categorized with DE in the group of insert dusts that contain natural silica (Haryadi et al. 1994, Subramanyam and Roesli 2000).
Preparation of nanosilica from sugarcane bagasse ash for enhanced insecticidal activity of diatomaceous earth against two stored-products insect pests
Published in Toxin Reviews, 2022
Basneh Saed, Masumeh Ziaee, Ali Reza Kiasat, Mina Jafari nasab
Stored products are greatly damaged by storage insect pests and result in quality as well as quantity losses of grains during storage (Kumar and Kalita 2017). Diatomaceous earth (DE) is a promising alternative to synthetic insecticides and have been used for controlling insects as grain protectant or structural treatment of grain storage facilities, and grain-handling machinery (Korunic 2013, Shah and Khan 2014). Over the recent years, different additives have been added to DE formulations to increase the efficiency in storage pest control (Ziaee et al.2019). Silica nanoparticles (SNPs) have fine particles which increase their toxicity and chance of particles contact to insect body resulted in more desiccation and insect death (Arumugam et al.2016, Ziaee and Ganji 2016). In addition, the small size of the particles leads to blockage of insects’ spiracle and trachea and suffocation (Debnath et al.2011). The synergistic effect of silica in combination with DE has been proven since many years ago (Shawir et al.1988, Ebeling 1994). Silica has been added to some commercial DE formulations such as Protect-It (Korunic 1999), Fossil-Shield® (Mewis and Ulrichs 2001), Protector® (Baldassari et al.2008), and Probe-A® (Badii et al.2014, Adarkwah et al.2017) in order to enhance their insecticidal potential. Silica nanoparticles can be used as additive in DE formulations to enhance their efficacy as grain protectant in grain storage facilities and grain-handling machinery (Korunic 1999, Delgarm et al.2019). Our recent study supported the synergistic efficacy of silica aerogel with DE for wheat grain protection against T. confusum and R. dominica. It was previously demonstrated that low rate of silica aerogel (10%) and deltamethrin (0.1%) can satisfactorily enhance the insecticidal efficacy of Mamaghan DE (natural Iranian DE deposit) and suppressed insect species progeny production (Delgarm et al.2019).
Clot activators and anticoagulant additives for blood collection. A critical review on behalf of COLABIOCLI WG-PRE-LATAM
Published in Critical Reviews in Clinical Laboratory Sciences, 2021
G. Lima-Oliveira, L. M. Brennan-Bourdon, B. Varela, M. E. Arredondo, E. Aranda, S. Flores, P. Ochoa
Diatomaceous earth is made of a fossil powder from microscopic algae that accumulated for hundreds of millennia in water basins that dried up. The main component is silicon dioxide, although other components depend on the extraction zone [77].