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.
Atmospheric particulates *
Bev-Lorraine True, Robert H. Dreisbach in Dreisbach’s HANDBOOK of POISONING, 2001
Dust containing silica is produced during rock cutting, drilling, crushing, grinding, mining, abrasive manufacture, pottery making, processing of diatomaceous earth, and volcanic eruptions. Talcum powder contains magnesium silicate. Many substances containing silica are capable of causing silicosis; particles less than 5 μm in diameter appear to be the most important in causing silicosis. The exposure limit for dusts containing crystalline quartz, such as tripoli, is 0.1 mg of respirable particles of quartz per cubic meter of air. Cristobalite and tridymite have an exposure limit of 0.05 mg/m3. For diatomaceous earth and silica gel, the total respirable mass should not exceed 10 mg/m3 of air; for precipitated silica, the respirable mass should not exceed 5 mg/m3.
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.
Influence of various operational parameters on the photocatalytic degradation of ciprofloxacin in aqueous media: a short review
Published in Toxin Reviews, 2023
Saifullahi Shehu Imam, Rohana Adnan, Noor Haida Mohd Kaus, Najm Us Saqib
The immobilization approach involves using carriers including zeolite (Jansson et al.2015), diatomite (B. Wang et al.2015), and bentonite (Patil et al.2016) to prevent agglomeration, thereby guaranteeing more active sites. The success of such an approach could be supported by the work of Jia et al. (2020) who used diatomite (D) to immobilize BiOCl. During the optimization, the amount of diatomite was varied between 0 and 70%. Compared to pure BiOCl, the adsorption ability of the BiOCl/diatomite composites decreased gradually with an increase in diatomite content. However, photo-degradability displayed an up-down trend. As the percentage of diatomite increased from 0 to 20%, the degradation rate of CIP also showed an increasing trend. Subsequently, a further increase in the percentage of diatomite from 20 to 70% caused the degradation rate to slowly decrease. Beyond diatomite content of 70%, the degradation rate rapidly reduced. The best performance was recorded using BiOCl/60%D, with a removal efficiency of 94% within 10 min under simulated solar light due to the synergistic effect of diatomite and BiOCl. Similar results were reported by Hassani et al. (2015) in which TiO2 loaded onto montmorillonite (TiO2/MMT). Following the increase in the surface area which resulted in an increased in the adsorption capability, the photocatalytic degradation efficiency was higher in the presence of TiO2/MMT compared to bare TiO2.
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).
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].