NewB
12
AssayforTECHNICON
IMMUNOJ
The Bayer company announces the availability of
vitaminB
12
assay for theTECHNICON IMMUNO
l immunoassay system, bringing its menu to 24
assays available worldwide. The new B
12
assay
offers excellent precision, sensitivity and repro–
ducibility across the entire assay range.
The TECHNICON IMMUNO l system - with
on-board refrigerated storageofall reagents provi–
ding true random-, continuous-, and immediate–
access performance- allows for continuous STAT
availability of all assays including the B
12
Assay.
For further information concerning the B
12
on
IMMUNO l , please contact:
Bayer Danmark A/S, phone: +45 38 17 71 00,
OYSuomenBayerAB, phone:+35 80 35 1621,
Bayer Norge A/S, phone: +47 67 06 80 00,
Bayer Sverige AB, phone: +46 31 83 98 00.
DAKOCystafin
C
Particle–
EnhancedTurbidimetry (PET)
New excellent marker for the glomerular
filtration rate (GFR)
Cystatin C is a small. non-glycosylated protein
with amolecularmass of 13 kDa.
l
t is produced by
all investigated nucleated cells at a rate which is
unaltered by inflammatory conditions. The gene
encoding for cystatin C is of the "house-keeping"
type which is compatiblewith a stable productian
rate by most cell types. These two features - low
moleeularmass and stable productian rate - imply
that the major determinant of cystatin C levels in
bloodplasma is theglomerularfiltration rate (GFR).
Ina recent publication, a fullyautomatedmethod
fordeterminationofcystatinC in serumandplasma
was presented, based on particle enhanced
turbidimetry (PET). The PET assay is very
Klinisk Kemi
i
Norden 2. 1995
convenient and rapid with a throughput of 90
samplesperhour.Theperformancedatawerefound
to be excellent with a total imprecison of about 2-
3% (CV) and with no important interference from
hyperlipemia, rheumatoid factor, bilirubin, or he–
moglobin.
The method was used for comparisons of the
relations between cystatin C and creatinine
concentrations andGFR (measured by the plasma
clearance of iohexo1) on a study group comprising
a typical clinical material. The results showed that
the cystatin C serum concentrations were a better
marker for GFR than creatinine concentrations.
Determinations of serum cystatin C levels should
be an interesting alternative or complement to the
traditional analysis of the serum creatinine
concentrations.
The DAKO Cystatin C PET Kit is based on
uniform polystyrene particles chemically coupled
with rabbitantibodies tohumancystatinCV.When
the coupled antibodies reacts with the sample, the
immunpartielesproduce light-scatteringsignalthat
enables turbidimetric detection.
The kit omprises immunoparticles, reaction
buffer, six calibrators, two controls and a detailed
working proeecture describing the performance of
thekit. Programming instructions forCobasMIRA/
FARA and Hitachi 717/91 l are included.
Instructions are also available for Hitachi 704,
Cobas Bio and Eppendorf ELANAnalyzer™.
The assay has a wide measuring range (0.5-14
mg/L) and a high security against antigen excess.
Reference
(l)
Kyhse-Andersen
J,
Schmidt C, Nordin G, An–
derssonB,Nilsson-
E
hle
P,
LindströmV,GrubbA.
SerumcystatinC,determinatedbyarapidautomated
particle-enhanced turbidimetric methos is a better
marker than serum creatinin for glomerular filt–
ration rate. Clin Chem 1994:40:1921-6.
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