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In analytical chemistry, sample preparation (working-up) refers to the ways in which a sample is treated prior to its analyses. Preparation is a very important step in most analytical techniques, because the techniques are often not responsive to the analyte in its in-situ form, or the results are distorted by interfering species.
Sample preparation for mass spectrometry is used for the optimization of a sample for analysis in a mass spectrometer (MS). Each ionization method has certain factors that must be considered for that method to be successful, such as volume, concentration , sample phase, and composition of the analyte solution.
Samples may first be cut down in size, for example, around a via in a PWB or around a ceramic capacitor soldered to a PWB. Samples may be prepared by encapsulation in a rigid material such as epoxy to keep the sample intact during grinding and with a vacuum step to fill in air gaps and create a solid sample with no voids. However, cross ...
A riffle box is a box containing a number (between 3 and 12) of "chutes" - slotted paths through which particles of the sample may slide. The sample is dropped into the top, and the box produces two equally divided subsamples. Riffle boxes are commonly used in mining to reduce the size of crushed rock samples prior to assaying.
The main advantages of this method include a significant reduction of sample preparation time (quick welding and cutting of nanowire at low beam current), and minimization of stress-induced bending, Pt contamination, and ion beam damage. [14] This technique is particularly suitable for in situ electron microscopy sample preparation.
The Siwoloboff method is used to determine the boiling point of small samples of liquid chemicals. A sample in an ignition tube (also called a fusion tube) is attached to a thermometer with a rubber band, and immersed in a Thiele tube, water bath, or other suitable medium for heating. A sealed capillary, open end pointing down, is placed in the ...
Solid-phase microextraction sampling. Solid phase microextraction, or SPME, is a solid phase extraction sampling technique that involves the use of a fiber coated with an extracting phase, that can be a liquid or a solid (), [1] which extracts different kinds of analytes (including both volatile and non-volatile) from different kinds of media, that can be in liquid or gas phase. [2]
Microwave digestion is a chemical technique used to decompose sample material into a solution suitable for quantitative elemental analysis. [1] It is commonly used to prepare samples for analysis using inductively coupled plasma mass spectrometry (ICP-MS), atomic absorption spectroscopy, and atomic emission spectroscopy (including ICP-AES).