An analytical method was developed to determine pesticides of various chemical classes in soil, juice and honey using analyte protectants to counteract the enhancement of the chromatographic response produced by the presence of matrix components (matrix effect). This effect was more pronounced for soil and honey samples than for juice samples; regarding the pesticide chemical class, organochlorine pesticides were less affected by the presence of matrix components than triazines and organophosphorus pesticides. Several analyte protectants (2,3-butanediol, L-gulonic acid γ-lactone, corn oil and olive oil) were tested for counteracting the observed matrix effect. L-Gulonic acid γ-lactone was an effective protecting agent for most of the pesticides studied in soil and honey samples, whereas olive oil was very effective for juice samples. The combination of these two protectants was found to be an effective analyte protectant for all compounds in soil and honey samples.

Electrophoresis of urine to evaluate protein fractions in dogs with proteinuria to differentiate glomerular from tubular damage has increased in recent years; however, capillary electrophoresis (CE) of urine has not been reported in a study of > 40 healthy animals, to our knowledge. We aimed to establish reference intervals (RIs) for the urine protein fractions obtained by CE of urine from healthy dogs. We obtained urine samples from 123 clinically healthy dogs of both sexes between December 2016 and April 2019; urine was frozen until CE was performed. The electrophoretic patterns obtained were divided into 5 protein fractions, and RIs were established in percentages and absolute values using nonparametric methods. RIs were obtained for the fractions (F) as follows: 5.5 to 56.2% for F1, 3.2 to 16.5% for F2, 3.5 to 16.2% for F3, 17.8 to 69.8% for F4, and 5.1 to 23.9% for F5. These RIs obtained by CE might be useful clinically as a basis for comparison with pathologic samples. Age was a statistically significant factor for F2 ( p = 0.01) and F3 ( p = 0.02), and sex was a statistically significant factor for F1 ( p = 0.03).