The raw pork LFD was also tested using cooked pork meat spiked
into a cooked beef background in the same manner (samples were
pre-mixed, and then cooked together for 15min at 120 °C) and then extracted
using an SDS-containing extraction solution at a 1:1 ratio and
mixed 1:1 with LFD running buffer (Method B). Near positive (60 set
as threshold) values were obtained at 1.0% cooked meat contamination
(see Table 2). This result was somewhat unanticipated due to the
deforming effects of thermal processing on serum albumins, and the
fact that the antibodies used in the development of the raw pork LFD
were raised against pig serum albumin (PSA). The use of the SDS-containing
buffer may have resulted in the relaxation of PSA aggregates in
the cooked sample thereby exposing key epitopes for binding to antibodies;
normal extraction measures relying on 0.9% saline solution
were unable to support detection of the cooked target analyte (data
not shown).