03/​20/​2020

HybriDetect and Temperature Effects

Higher Temper­a­tures: Stability aspects and assay Parameters

The general robustness is a charac­ter­istic feature of lateral flow devices (LFD’s). Even during longer trans­ports and extreme weather condi­tions LFD’s remain stable. Temper­ature is an important factor when it comes to robustness. Therefore our HybriDetect test strips are regularly tested at higher temper­a­tures.

Especially in the devel­opment of NALFIA’s (Nucleic Acid Lateral Flow Immunoassays), the temper­ature can influence the test result signif­i­cantly. The hybridization of amplifi­cates is classified as partic­u­larly inter­esting. The use of a defined temper­ature is a crucial parameter to maintain specific hybridizing condi­tions.

Higher temper­a­tures can also be under­stood as tool in the assay procedure to achieve certain results.

Higher Temper­a­tures: Perfor­mance Test

For this reason, Milenia Biotec GmbH took a closer look at this issue: The universal test strips HybriDetect (MGHD1) and HybriDetect 2T (MGHD2 1) were examined under different condi­tions with dilution series of labelled dsDNA. The purified labelled amplifi­cates were placed into running buffer and warmed to the desired temper­ature. Test strips were prewarmed as well for 30 minutes. After rewarming Lateral Flow Analysis was initiated. After five minutes signals were documented. The overall results are shown in the following figure.

Figure 1: Influence of higher temper­a­tures to LFA-​​performance of HybriDetect test strips. Red triangles indicate temper­ature related nonspe­cific signals on test lines.

The results illus­trate the robustness of the dipsticks. Even at 65 °C, a sensitive analysis is possible without a visible loss of perfor­mance. Nonspe­cific signal appear over 70°C, especially on the testline 2 of the HybriDetect 2T (red triangles in the figure). This effect is easy to explain. Like most LFD’s the HybriDetect platform includes antibodies. If these antibodies are exposed to temper­a­tures over 70°C, denat­u­ration takes place. This results in non-​​specific signals.

However, the full function­ality of the Hybrid­Detect test strips was demon­strated in the tested range of 20°C to 65 °C. Temper­ature should be considered as an additional tool in assay devel­opment. Try to profit from this feature!