scholarly journals Particle-Enhanced Turbidimetric Immunoassay

2020 ◽  
Author(s):  
1999 ◽  
Vol 45 (9) ◽  
pp. 1557-1561
Author(s):  
Sandra Guaita ◽  
Josep MA Simó ◽  
Natàlia Ferré ◽  
Jorge Joven ◽  
Jordi Camps

Abstract Background: The measurement of immunoglobulin E (IgE) in serum is widely used in the diagnosis of allergic reactions and parasitic infections. We describe here a fully automated assay for human IgE suitable for routine application in a general chemistry analyzer. Methods: We used an ILab 900® analyzer. This instrument automates a particle-enhanced immunoturbidimetric assay with an analysis time of 9 min. Results: The assay was linear in the range 4–1000 kIU/L (r = 0.9998). The intra- and interassay CVs at 57, 235, and 434 kIU/L were <3.5% and <7.4%, respectively. The detection limit was 4 kIU/L. Hemoglobin (≤16 g/L), bilirubin (≤250 μmol/L), and myeloma paraproteins did not interfere with the assay. The assay showed good correlation with a microparticle enzyme immunoassay (r = 0.998) with a mean difference between methods of −6 ± 26 kIU/L. Conclusion: The new automated serum assay for IgE is an attractive alternative that avoids the need for dedicated instrumentation.


1997 ◽  
Vol 43 (6) ◽  
pp. 983-989 ◽  
Author(s):  
Pamela Bean ◽  
Karsten Liegmann ◽  
Trond Løvli ◽  
Christina Westby ◽  
Erling Sundrehagen

Abstract Carbohydrate-deficient transferrin (CDT) may now be the most valuable biological marker for diagnosis of alcohol abuse. We compared the diagnostic performance of two new CDT tests, Axis %CDT turbidimetric immunoassay (TIA) and Axis %CDT HPLC, against Specialty Laboratories’ isoelectric focusing/immunoblotting/laser densitometry (IEF/IB/LD). Both Axis tests include one-half the concentration of trisialotransferrin isoforms in their CDT quantitation schemes. Considering an alcohol abuse prevalence of 7%, Axis %CDT TIA shows a sensitivity of 87% at 98% specificity and a positive predictive value (PPV) of 0.75; %CDT HPLC shows a sensitivity of 87% at 100% specificity for a PPV of 1, and the IEF/IB/LD shows 81% sensitivity at 94% specificity for a PPV of 0.5. All three CDT tests show the same negative predictive value (0.98). Both Axis procedures perform better than IEF/IB/LD in the diagnosis of alcohol abuse; %CDT TIA is available in several semiautomated, cost-effective formats.


2000 ◽  
Vol 46 (2) ◽  
pp. 193-197 ◽  
Author(s):  
Borut Štabuc ◽  
Levin Vrhovec ◽  
Mirna Štabuc-Šilih ◽  
Tomaž Edvard Cizej

Abstract Background: Serum cystatin C, a cysteine protease inhibitor, has been suggested as a new marker of glomerular filtration rate (GFR). This study explored the possibility of replacing the creatinine clearance (CrCl) estimation of GFR with cystatin C in early detection of renal impairment in cancer patients on chemotherapy. Methods: Serum creatinine and cystatin C concentrations as well as 24-h CrCl were determined simultaneously in 72 cancer patients. Among them, 60 were treated with combined chemotherapy with cisplatin (CDDP). Creatinine was determined enzymatically with a spectrophotometric method. Serum cystatin C was determined by a particle-enhanced turbidimetric immunoassay. Results: Cystatin C and creatinine correlated significantly (P = 0.001) with CrCl. The correlation was significantly better for cystatin C than creatinine (r = 0.84 vs 0.74; P = 0.01). Stepwise regression analysis identified no differences for the correlations between cystatin C and CrCl in patients with or without metastases (r = 0.82 and 0.84, respectively) as well as before treatment and before the fourth cycle of chemotherapy (r = 0.70 and 0.75, respectively). A cystatin C cutoff concentration of 1.33 mg/L had 87% sensitivity and 100% specificity for detecting CrCl <78 mL/min. ROC analysis indicated that cystatin C was superior to serum creatinine for predicting CrCl <78 mL/min (P <0.04). Conclusions: Serum cystatin C is superior to serum creatinine for detection of decreased CrCl and potentially for the estimation of GFR in cancer patients independent of the presence of metastases or chemotherapy.


2012 ◽  
Vol 45 (4-5) ◽  
pp. 339-344 ◽  
Author(s):  
Azita Sohrabian ◽  
Feria Hikmet Noraddin ◽  
Mats Flodin ◽  
Annika Fredricsson ◽  
Anders Larsson

Digestion ◽  
2018 ◽  
Vol 98 (2) ◽  
pp. 75-80 ◽  
Author(s):  
Koshiro Tsutsumi ◽  
Chika Kusano ◽  
Sho Suzuki ◽  
Takuji Gotoda ◽  
Kazunari Murakami

1986 ◽  
Vol 32 (6) ◽  
pp. 1020-1022 ◽  
Author(s):  
J A Viedma ◽  
A de la Iglesia ◽  
M Parera ◽  
M T López

Abstract This rapid, sensitive equilibrium turbidimetric immunoassay for quantification of alpha 1-antitrypsin involves a monospecific antibody, polyethylene glycol 6000 to accelerate and enhance the immunoprecipitation reaction, and Tween 20 surfactant to decrease and stabilize the sample-blank values. Turbidity at 334 nm is measured by an automated discrete analyzer. Grossly lipemic, icteric, or hemolyzed samples can be assayed. Correlation with results by radial immunodiffusion (RID) was excellent (r = 0.97, n = 84). Analytical recovery averaged 97.7 (SD 2.9)%. Within-run CVs ranged from 1.6 to 1.9%, between-day CVs from 2.0 to 3.5%. Reference values for healthy adults (n = 147) were determined by parametric estimation (for an assumed normal distribution of untransformed data). The lower limit (g/L) with its 0.90 confidence interval is 1.23 (range 1.18-1.28), the upper limit is 2.15 (2.10-2.20), and the mean is 1.69 g/L.


2013 ◽  
Vol 46 (12) ◽  
pp. 1128-1130 ◽  
Author(s):  
Konstantinos Makris ◽  
Efthimia Nikolaki ◽  
Konstantinos Nanopoulos ◽  
Konstantinos M. Pirgakis ◽  
Chrisostomos K. Maltezos

Sign in / Sign up

Export Citation Format

Share Document