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.
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).he breakdown products of THC (its metabolites) can be detected in the urine days or even weeks after stopping its use, depending upon whether a person is an occasional or a regular marijuana user. Urine tests may not be an indicator of current marijuana use but more of past drug use.