MAc Test

The MAc Test allows you to evaluate photometrically the Metabolic Acidity, that is the sum of organic and inorganic acids produced by cellular metabolic activity.

Knowing the degree of metabolic acidity makes it possible to prevent tissue damage caused by free radicals attack and hence oxidative stress and its unintended consequences.


The cellular metabolic activity produces variable amounts of inorganic acids, such as carbonic acid, and organic acids such as lactic acid, uric acid, free fatty acids esterified or not (NEFA, not esterified fatty acids), etc., each of which has a precise origin, follows a very specific metabolic purpose and performs a specific function.

The degree of acidity detectable in the microcirculation, which reflects the sum of the production of different acids derived from tissue metabolism plays a physiological role in the regulation of exchange between blood and cells. In fact, increased levels of acidity within certain limits reduces vascular tone (vasodilation), and promotes the transfer of oxygen from hemoglobin, resulting in improved perfusion of tissues and organs. However, an excessive increase of total acidity, changing the shape of the plasma proteins, facilitates the release of transition metals, such as iron and copper from transferrin and ceruloplasmin. It originates the activation of the Fenton reaction and the perossidic radical generation by circulating hydroperoxides, which are the basis of oxidative stress and its fearsome consequences (e.g. atherosclerosis). Severe and/or protracted acidosis, however, can extend from the plasma to the tissues, aided by the concomitant changes in the extracellular matrix tissues ( for example increased proteolysis and reduction of protidosynthesis), resulting in an amplification of the damage from oxidizing chemical species (free radicals).

Ultimately, an abnormal increase in the level of acidity in the microcirculation (microacidosis) is often "the prelude" for oxidative stress.

Unfortunately, until today, the only test that can measure the acid-base balance in blood is the pH test, which quantifies the concentration of hydronium ions (H3O+) in serum/plasma. Its values are between 7.38 7.34 but this is a weak or poor measure, when altered, of the acidity of the blood and, above all, provide no useful indication for the purposes of a possible correction by alkalization.

The MAc Test, test of Metabolic Acidity (titration organic acidity), on the other hand, determines this important parameter according to the principle of acidity (technically, adding equivalent bases as a function of acid concentration detected).

Working conditions

The test must be carried on fresh whole blood just collected.
It can be used both on dedicated systems (FREE Carpe Diem e FREE DUO), and on standard manual photometers.

Interpretation of results

Optimal values are below 440 p.p.m. Higher values suggest a microacidosis condition. In this case, the doctor will decide, according to the clinical status of each patient, the best medical approach to bring values back to the optimal status.

Reference values expressed as mEq/L
 Normal 1.65 - 4.95 
Light acidosis 4.95 – 6.6 
Acidosis 6.6 - 11 
Strong acidosis > 11 
Light alkalosis < 1.65 
Alkalosis < 0.55 
Strong alkalosis < 0.11 

Keeping the acidity within the boundary of the optimal values is the simplest of method capable of preventing tissue damage from free radicals and, thereby, oxidative stress and its unintended consequences. In addition, since the food intake, through acidifying or alkalizing nutrients, can affect the acidity, the measure of the acidity is the most correct way, from a scientific point of view, to choose the foods that best suits your body in a particular metabolic environment and monitor the temporal effects on health status.


DIACRON INTERNATIONAL s.r.l is the leader company in research and evaluation of oxidative stress. Our company produces and sells analytical dedicated instruments, kits and accessories for oxidative stress assessment in Human, Veterinary and Agrifood fields.