References Introduction Starting in the early s, I reviewed in detail the historical experiments on the 19th Century luminiferous cosmic ether, and related vitalist concepts about a life-energy continuum in space.
Etymology[ edit ] According to Etymology Online,  the verb assay, at least since the 13th century, meant "to try, endeavor, strive; test the quality of", from Anglo-French assaier, from assai n.
For assay of currency coinsthis literally meant analysis of the purity of the gold or silver or whatever precious component was used to represent the true value of the coin.
This might have translated later possibly after the 14th century into a generalized meaning of analysis,[ citation needed ] e. General steps[ edit ] An assay analysis is never an isolated process and must be combined with pre- and post-analytic procedures.
The information communication e. Like any multi-step information handling and transmission systems, variation and errors in the communicated final results of an assay involve corresponding parts in every such step; i. Since the assay itself the analytic step gets much attention,  steps that get less attention by the chain of users, i.
It might involve a simple centrifugal separation or washing or filtration or capture by some form of selective binding or it may even involve modifying the target e. Generally there are multiple separate steps done before an assay and are called preanalytic processing.
But some of the manipulations may be inseparable part of the assay itself and will not thus be considered pre-analytic. The presence and quantity of that analyte is converted into a detectable signal generally involving some method of signal amplification, so that it can be easily discriminated from noise and measured - e.
Sometimes the concentration of the analyte is too large and in that case the assay may involve sample dilution or some sort of signal diminution system which is a negative amplification. A system of deciphering the amplified signal into an interpretable output that can be quantitative or qualitative.
It can be visual or manual very crude methods or can be very sophisticated electronic digital or analog detectors.
Signal enhancement and noise filtering may be done at any or all of the steps above. These may simply be in the form of a narrow band-pass optical filer, or a blocking reagent in a binding reaction that prevents nonspecific binding or a quenching reagent in a fluorescence detection system that prevents "autofluorescence" of background objects.
An end point assay, in which a single measurement is performed after a fixed incubation period; or A kinetic assay, in which measurements are performed multiple times over a fixed time interval.
Kinetic assay results may be visualized numerically for example, as a slope parameter representing the rate of signal change over timeor graphically for example, as a plot of the signal measured at each time point.
For kinetic assays, both the magnitude and shape of the measured response over time provide important information. Usual assays are simple or single target assays which is usually the default unless it is called multiplex.
Multiplex assays are used to simultaneously measure the presence, concentration, activity, or quality of multiple analytes in a single test. Generally they have a few more gradations than just two outcomes, positive or negative, e. An example of such an assay used in coagulation testing laboratories for the commonest inherited bleeding disease - Von Willebrand disease is VWF antigen assay where the amount of VWF present in a blood sample is measured by an immunoassay.3 It is VERY important that you take care to prevent contamination because of the large number of experiments that will be performed.
Be sure to use deionized water in all chemical tests. Qualitative Analysis of Anions using Spot Tests filled with deionized water, Bunsen burner, centrifuge.
Chem 12 Santa Monica College Safety and Waste Disposal. 1. All waste generated by this lab is toxic and must be disposed of in the hazardous waste container!
2. Unused sample of the unknown should be discarded in the hazardous waste.
In the qualitative analysis procedure, the chemical properties of an unknown substance are determined by systematically reacting the unknown with a number of different reagents. The remaining tests must be perfomed on a solution of the compound. The test may be performed on a small sample of the unknown treated with concentrated HCl or. The flame test is used to visually determine the identity of an unknown metal or metalloid ion based on the characteristic color the salt turns the flame of a Bunsen burner. The heat of the flame excites the electrons of the metals ions, causing them to emit visible light. 1 Introduction Qualitative analysis is a method used for identification of ions or compounds in a sample. In many cases, qualitative analysis will also involve the separation of ions or compounds in a mixture. Examples of qualitative tests would include ion precipitation reactions (solubility tests).
Facts, figures and findings from application of Toxkit microbiotests are reported in a large number of publications, reports and presentations at scientific symposia and workshops.
At least one author of an abstract must be registered for the Congress in order to be included in the abstract book. One author can present only ONE abstract. In analytical chemistry, quantitative analysis is the determination of the absolute or relative abundance (often expressed as a concentration) of one, several or all particular substance(s) present in a sample.
1. NAME Substance Promethazine (INN, ) Promethazine hydrochloride (BAN, ; USAN, ) Promethazine theoclate (BAN, ) Group Antihistamines for systemic use (R06)/Phenothiazine derivatives (R06AD) (ATC classification index [WHO] ]) Synonyms Diprazinum; Proazamine Chloride; Promethazini Hydrochloridum; Promethazinium Chloride.