LARK® MULTI-ELEMENT HOLLOW CATHODE LAMP

LARK® multi-element lamps have cathode compositions that enable the same lamp to be used for determination of multiple elements. They are available as either coded or economical uncoded lamps. Coded lamps are element coded for automatic recognition by the Agilent AA, simplifying operation and eliminating errors when changing the lamp position. Uncoded lamps provide the same excellent performance as coded lamps.

The light source used in Atomic Absorption Spectroscopy is unique. It looks like any other lamp but its uniqueness lies in the fact that its cathode is made of the same element which you have to determine in your sample. This means that you have to use a different lamp for every element whose analysis is required. Light sources in Atomic Absorption Spectroscopy briefly provides introduction to LARK® hollow cathode lamps and LARK® multi element hollow cathode lamps. Use of multi element lamps offers several benefits to the user in terms of time and cost:

• Multi element lamps are available in combinations of 2-7 different elements

• Cost savings as different LARK® hollow cathode lamps need not be purchased for each element to be analyzed

• Higher sample throughput can be achieved as there is no need for initial warm up for separate lamps

• Elements present in LARK® multi element lamps can be determined sequentially using same lamp without need for changing different lamps

• LARK® Hollow cathode lamps have a shelf life and even if not used cannot be stored indefinitely. Use of multi element lamps does not require purchase and storage of different constituent element lamps

LARK® 1.5″ x 38mm Dia, Length 160mm MULTI ELEMENT HOLLOW CATHODE LAMP Series LHB (NEW Type)
ELEMENT	#Code	Order Code
Pb-Cd	#1L9-121	LHB-201161
Sr-Al	#1L9-122	LHB-201162
Pb-Cu	#1L9-123	LHB-201163
Fe-Mg	#1L9-124	LHB-201164
Ca-Mg	#1L9-125	LHB-201165
Ag-Cd	#1L9-126	LHB-201166
K-Na	#1L9-127	LHB-201167
Zn-Cu	#1L9-128	LHB-201168
Sn-Al	#1L9-129	LHB-201169
Sn-Cu	#1L9-130	LHB-201170
Ca-Mg-Al	#1L9-131	LHB-201171
Ca-Mg-Zn	#1L9-132	LHB-201172
Cu-Fe-Mn-Zn	#1L9-133	LHB-201173
Zn-Cu-Fe	#1L9-134	LHB-201174
Zn-Cu-Ca-Mg-Fe	#1L9-135	LHB-201175
Series LHA (Regular Type)
Al-Ca-Cu-Fe-Mg-Mn-Ni	#1L9-136	LHB-201176
Co,Cr, Cu, Fe, Mn, Ni	#1L9-137	LHB-201177

Important operational features from manufacturer point of view are discussed below:

• The essential feature of a hollow cathode lamp is to generate a narrow emission line of the element which is to be tested. The same is true for a multi element hollow cathode lamp. It should give narrow emission line of the constituent elements. Such lines should be well resolved to be free of interferences and also have sufficient intensity

• The multi element lamp should be commercially viable in terms of user applications. The element combinations should be able to cater to the needs of different market segments such as environmental, drinking water, ornaments and base metal analysis.

• The metals should be compatible with one another and form homogeneous alloys.

• It should be possible to guarantee a lifetime for lamp usage. Single element lamps are normally guaranteed for 5000 milliampere-hours. The guaranteed lifetime of multi element lamp should not be comparable and not far too less.

• Choice of elements and their relative proportions need to be carefully evaluated to get optimum usage features

• Though economical it is commonly believed that multi element lamps compromise on sensitivity as the analytical line intensities are lower than single element lamps and though not significant there can be interference due to presence of other elements. Some manufacturers have overcome such problems by using boosted discharge lamps which enhance the analytical lines of the constituent elements.