Lithium determination

Analysis. Lithium can be detected by the strong orange-red emission of light in a flame. Emission spectroscopy allows very accurate determination of lithium and is the most commonly used analytical procedure. The red emission line at 670.8 nm is usually used for analytical determinations although the orange emission line at 610.3 nm is also strong. Numerous other methods for lithium determinations have been reviewed (49,50). 

A5. Amdisen, A., Serum lithium determinations for clinical use. Scand. J. Clin. Lab. Invest. 20, 104-108 (1967). 

L8. Levy, A. L., and Katz, E. M., A comparison of serum lithium determinations using flame photometry and atomic absorption spectrophotometry. Clin. Chem. 16, 840-842 (1970). 

Vll. Villeneuve, A., Dery, R., and Genest, P. H., A simple micromethod for serum lithium determination. Clin. Biochem. 4, 194-195 (1971). 

Toxicity is closely related to serum lithium levels and can occur at therapeutic doses. Facilities for serum lithium determinations are required to monitor therapy. 

With normal renal function, all that may be necessary is watchful waiting, careful monitoring of the clinical status, and repeated serum lithium determinations. 

The inadvertent use of lithium heparin as an anticoagulant in the collection tube will lead to a spuriously high serum lithium determination. 

The first commercially available flame photometer was introduced in the 1940s by the Perkin-Elmer Corporation. In 1948, Beckmann Instruments, Inc., introduced a flame attachment that could be used with their popular model D.U. spectrophotometer. By the late 1950s, instruments had been developed that used lithium as an internal standard to maximize precision. Autodilution features and microprocessor-controlled operations became widely used options in the 1970s. The most recent significant development was the introduction of cesium as the internal standard, by Instrumentation Laboratory, Inc. (Figs. 1-3). This development makes concurrent lithium determinations more practical. 

Routine serum lithium estimations on blood taken 12 hr after the previous dose give no indication of the peak serum lithium concentrations. These usually occur within 4 hr of the dose and are associated with any transient side effects that may occur (50). The pharmacokinetics of lithium preparations is studied by administration of a single test dose of the drug followed by timed sequential blood lithium determinations. Such studies are of interest for the following reasons ... 

Geeil W and Stellee B (1992) Lithium determination in outpatient clinics by an ion-selective electrode in venous and capillary whole blood. Psychiatry Res 44 71-77. 

Solubilities of carbon in alkali metals can be expressed by the same type of equations as formulated for the Me—O systems, in spite of the fact that the compounds are less stable. The solubility of lithium acetylide in lithium determined first by Fedorov and Su by means of a X-ray diffraction method has been recently revised In this study, the acetylene evolution method has been applied. The saturation Eq. (12) is based on this most recent study. 

Lithium determination with the graphite tube technique... 

Lithium determinations are carried out most accurately by A AS [13] but more usually by flame emission spectroscopy [82]. A sample is aspirated through a flame during which spectral changes are measured. Both require the separation by centrifugation of blood cells from blood plasma to enable the preparation of a diluted plasma sample. 

Measuring erythrocyte lithium concentrations does not appear to offer any advantages over serum lithium determinations in the management of lithium toxicity [94 ]. 

Lead, determination of 205, 206 Linear alkylbenzene sulphonates, determination of 202 Lithium, determination of 205, 206, 223,229... 

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