The ionic composition of interstitial and intravascular fluids is the same. Proteins, however, are kept with the vascular compartment, at least to a degree, by the vascular wall, which is a semi-permeable membrane. The concentration of proteins is much higher in the plasma sector than in the interstitial sector.
Detection of marijuana using swab drug test can vary from person to person taking into account the different conditions like general health, different fluid intake, metabolism, etc.
THC Drug Test. A marijuana drug test is the technical analysis of a biological specimen, such as urine, blood, hair, sweat or saliva, to determine the presence or absence of the active ingredients of marijuana (mainly THC) or its metabolites (breakdown products).t is important to note that urine tests are usually conducted to test for the presence of THC metabolites which indicates marijuana use. Blood tests are conducted when the amount of THC still present in the system has to be ascertained.