RESUMO
This procedure for routine quantification of albumin in urine is based on the dye-binding properties of albumin with bromphenol blue. The absorbance of 100 microL of urine mixed with 3 mL of color reagent is measured against blank reagent at 610 nm after 30 s. Results vary linearly with albumin concentration up to 6 g/L. The reaction is pH independent in the physiological range. It is not subject to substantial interference by uric acid, creatinine, calcium, sodium chloride, or bilirubin. The presence of globulins produces a small positive error. Within-run precision (CV) was 4.8, 1.5, and 0.9%, and day-to-day precision was 11.2, 2.0, and 1.9%, for samples containing albumin at about 0.1, 1.0, and 6.0 g/L, respectively. Results by a radial-immunodiffusion method (x) correlated well with those by the proposed method (y): r = 0.986; y = 0.98x + 0.096; n = 64. The method can also be used to detect globulins, such as Bence Jones protein, by measuring the ratio of the absorbance at 30 min to that at 30 s.
Assuntos
Albuminúria/urina , Azul de Bromofenol , Fenóis , Adolescente , Adulto , Feminino , Humanos , Concentração de Íons de Hidrogênio , Imunodifusão , Masculino , Pessoa de Meia-Idade , Controle de Qualidade , Valores de Referência , EspectrofotometriaRESUMO
A micromethod for the analysis for chloride, based on the chemical precipitation of silver chloride by radial diffusion through agar gel containing silver nitrate, is described. The method is simple to run, requires little or no instrumentation, and requires only 10 mul of sample. Results by coulometric titration (Buchler Cotlove Chloridometer) correlated well for serum (r = 0.961), urine (r = 0.997), cerebrospinal fluid (r = 0.991), and sweat (r = 0.998). Other halide ions or protein do not interfere. Precision studies gave a within-day reproducibility (CV) of 1.3% and a day-to-day variability of 2.1% for a serum sample averaging 115 mmol/liter.
Assuntos
Cloretos/análise , Ágar , Cloretos/sangue , Difusão , Estudos de Avaliação como Assunto , Humanos , Iodetos , Métodos , Microquímica , Nitrato de Prata , Suor/análiseRESUMO
An automated method for the enzymatic determination of ceruloplasmin with o-dianisidine dihydrochloride as substrate is described. The method enables the measurement of 30 samples per hour with a coefficient of variation (day-to-day) of 2.8%. Results correlate well (r equals 0.99 with those obtained by the corresponding manual method
