Improved sample treatment for the determination of insoluble soap in sewage sludge samples by liquid chromatography with fluorescence detection.
Summary of "Improved sample treatment for the determination of insoluble soap in sewage sludge samples by liquid chromatography with fluorescence detection."
A new selective and sensitive method for the determination of insoluble fatty acid salts (soap) in sewage sludge samples is proposed. The method involves a clean up of sample with petroleum ether, the conversion of calcium and magnesium insoluble salts into soluble potassium salts, potassium salts extraction with methanol, and a derivatization procedure previous to the liquid chromatography with fluorescence detection (LC-FLD) analysis. Three different extraction techniques (Soxhlet, microwave-assisted extraction and ultrasounds) were compared and microwave-assisted extraction (MAE) was selected as appropriate for our purpose. This allowed to reduce the extraction time and solvent waste (50 mL of methanol in contrast with 250 mL for Soxhlet procedure). The absence of matrix effect was demonstrated with two standards (C(13:0) and C(17:0)) that are not commercials and neither of them has been detected in sewage sludge samples. Therefore, it was possible to evaluate the matrix effect since both standards have similar environmental behaviour (adsorption and precipitation) to commercial soaps (C(10:0)-C(18:0)). The method was successfully applied to samples from different sources and consequently, with different composition.
Research Group of Analytical Chemistry and Life Sciences, Department of Analytical Chemistry, University of Granada, Campus of Fuentenueva, E-18071 Granada, Spain.
This article was published in the following journal.
- PubMed Source: http://www.ncbi.nlm.nih.gov/pubmed/20801371
- DOI: http://dx.doi.org/10.1016/j.talanta.2010.07.044
Medical and Biotech [MESH] Definitions
A genus of gram positive, acetogenic, thermophilic bacteria in the family Thermoanaerobacteraceae. Known habitats include HOT SPRINGS, horse manure, emu droppings, and sewage SLUDGE.
The sole genus in the family Methanospirillaceae whose organisms are progressively motile by means of polar, tufted flagella. They have been isolated from sewage-sludge and pear waste digesters as well as marine and non-marine habitats.
The absence of a useful purpose or useful result in a diagnostic procedure or therapeutic intervention. The situation of a patient whose condition will not be improved by treatment or instances in which treatment preserves permanent unconsciousness or cannot end dependence on intensive medical care. (From Ann Intern Med 1990 Jun 15;112(12):949)
Flow Injection Analysis
The analysis of a chemical substance by inserting a sample into a carrier stream of reagent using a sample injection valve that propels the sample downstream where mixing occurs in a coiled tube, then passes into a flow-through detector and a recorder or other data handling device.
Microscopy, Scanning Tunneling
A type of scanning probe microscopy in which a very sharp conducting needle is swept just a few angstroms above the surface of a sample. The tiny tunneling current that flows between the sample and the needle tip is measured, and from this are produced three-dimensional topographs. Due to the poor electron conductivity of most biological samples, thin metal coatings are deposited on the sample.
In this work we present a monitoring study of linear alkylbenzene sulfonates (LAS) and insoluble soap performed on Spanish sewage sludge samples. This work focuses on finding statistical relations bet...
The characterisation of a laboratory quality control material (QCM) for dibutyltin (DBT) and tributyltin (TBT) in sewage sludge is described. The reference values were determined by the use of two dif...
This work experimentally elucidates the efficiencies of sono-alkalization treatment on municipal sewage sludge. The total solids (TS) concentration of the sewage sludge was pre-adjusted at 29.7 g/L. T...
The effects of using dried sewage sludge as additive on cement property in the process of clinker burning were investigated in this paper. The eco-cement samples were prepared by adding 0.50-15.0% of...
The purpose of this study was to enhance the efficiency of anaerobic co-digestion with sewage sludge using pretreatment technologies and food waste. We studied the effects of various pretreatment meth...
Introduction. Lymphatic filariasis is a devastating mosquito-transmitted parasitic disease that causes lymphedema or elephantiasis of the leg in 15 million persons, the majority of whom a...
The purpose of this study is to assess the role of dietary fibre in Irritable Bowel Syndrome (IBS) treatment, in particular the role of increasing the content of soluble or insoluble fibre...
Surgical site infections (SSI) constitute a significant health-economic and clinical challenge. The investigators conducted a cluster-randomized, cross-over study to compare the efficacy o...
Primary Objective: To evaluate the potential of hydratation and renewal of the mucosa, through corneometry measurement and individual questionnaire perception. Secondary Objective:...
Primary Objective: - To prove the efficacy superiority in reducing the genital odor and increase hydration in mucosa genital comparing the use of Dermacyd (different fragrances) and Glyc...