Development of an enzymatic chromatography strip with nicotinamide adenine dinucleotide-tetrazolium coupling reactions for quantitative l-lactate analysis.

In this study, a dry assay of l-lactate via the enzymatic chromatographic test (ECT) was developed. An l-lactate dehydrogenase plus a nicotinamide adenine dinucleotide (NADH) regeneration reaction were applied simultaneously. Various tetrazolium salts were screened to reveal visible color intensities capable of determining the lactate concentrations in the sample.

Numerical analysis of an immunochromatographic test strip reader in abused drugs screening.

A point-of-care immunoassay strip reader, Uniscan™, was applied to detect methamphetamine, opiate, and marijuana in human urine by providing numerical apparent drug concentrations. Calibration curves were determined by a nonlinear regression. The cutoff was verified using spiked controls.

Evaluation on the use of reactive dye-modified polylysine as the biomarker in immunochromatographic test application.

An improved dye immunochromatographic test (DICT) using polylysine (PL) as conjugate spacer loading dye molecules to enhance chromophor color intensity with the potential of a simultaneous multicolored assay has been developed. To construct this new effective chromophor, a dyeing process coupling a reactive dye, Procion Blue MX-7RX (PB7RX), with PL of different molecular weights was performed. The optimal conjugate condition between PB7RX and PL was studied.

Development of a chromatographic strip assay for detection of porcine antibodies to 3ABC non-structural protein of foot-and-mouth disease virus serotype O.

A chromatographic strip assay was developed for rapid detection of serum antibodies to non-structural protein of foot-and-mouth disease virus. The assay was based on Escherichia coli-expressed 3ABC non-structural protein and an immunochromatographic technique, which shortened the detection time to about one hour. The sensitivity of the assay was determined to be 96.

Development of a disperse dye immunochromatographic test for the detection of antibodies against infectious bursal disease virus.

For investigating the feasibility of using disperse dyes as an immunoassay chromogenic marker, a disperse dye, DADISPERSE NAVY BLUE SP, was selected in analyzing antibody against infectious bursal disease virus (anti-IBDV). With the color intensity revealed in the disperse dye immunochromatographic test (DICT) strip as the objective function, the optimal dyeing conditions were found as follows: dye concentration absorbance (at lambda(max)=587nm)=3, pH 7, 50 degrees C, for 10min. Under these conditions, the resultant dyed-antibody (rabbit anti-chicken) can produce an optimal color intensity reading of 55,054 on the strip.

Optimized dyeing conditions of immunoprotein with reactive dye Procion Blue MX-7RX.

For investigating the feasibility of using reactive dyes as an immunoassay marker, a dichlorine triazine dye, Procion Blue MX-7RX, was employed to stain the antibody against human serum albumin (anti-HSA). With the color intensity revealed in the immunochromatographic test strip as the objective variables, the optimal dyeing conditions were found as follows: pH 11.4, temperature 35.

Evaluation and application of conducting polymer entrapment on quartz crystal microbalance in flow injection immunoassay.

An immunosensor employing conducting polymer entrapment (CPE) method to immobilize immuno-protein on the quartz crystal microbalance (QCM) for clinical flow-injection-analysis (FIA) purpose was exploited. By comparing the CPE approach and the conventional physical immobilization (PI) method, a frequency shift of the former was 47% higher than that of the latter when measuring at 0.5 mg/ml human serum albumin antibody concentration.