A method of aspirating a dose of a liquid by pipetting in an aspirating cycle, or of manufacturing a dose of a liquid including such aspirating method, the method comprising: a) after a pipette containing a work fluid has reached an aspiration position; b) initiating at a point in time a suctioning action to said work fluid; c) sensing by means of a sensor arrangement at least one prevailing first parameter, being dependent from an effect of said suctioning action, the first parameter being the pressure course in said work fluid or a flow course in said work fluid, and analyzing said at least one prevailing first parameter within a first time span subsequent said initiating, said analyzing comprising detecting an occurrence of an extremum (EXTR) of the first time derivative of said prevailing first parameter and determining the extremum value of said first time derivative as said at least one result of said analyzing; d) determining at least one test-criterion in dependency of at least one result of said analyzing, wherein the test criterion is a range of value of the first time derivative of a pressure course in said work fluid or of a flow course in said work fluid, and wherein the range is determined in dependency of the extremum value (EXTR); e) checking at least one second prevailing parameter, wherein the second prevailing parameter is the monitored first time derivative of a pressure course in said work fluid or of a flow course in said work fluid, within a second time span subsequent to said determining, upon whether the values of the first time derivative remains within the range during the second time span; f) identifying said aspirating cycle as acceptable or as not acceptable in dependency of a result of said checking. a) after a pipette containing a work fluid has reached an aspiration position; b) initiating at a point in time a suctioning action to said work fluid; c) sensing by means of a sensor arrangement at least one prevailing first parameter, being dependent from an effect of said suctioning action, the first parameter being the pressure course in said work fluid or a flow course in said work fluid, and analyzing said at least one prevailing first parameter within a first time span subsequent said initiating, said analyzing comprising detecting an occurrence of an extremum (EXTR) of the first time derivative of said prevailing first parameter and determining the extremum value of said first time derivative as said at least one result of said analyzing; d) determining at least one test-criterion in dependency of at least one result of said analyzing, wherein the test criterion is a range of value of the first time derivative of a pressure course in said work fluid or of a flow course in said work fluid, and wherein the range is determined in dependency of the extremum value (EXTR); e) checking at least one second prevailing parameter, wherein the second prevailing parameter is the monitored first time derivative of a pressure course in said work fluid or of a flow course in said work fluid, within a second time span subsequent to said determining, upon whether the values of the first time derivative remains within the range during the second time span; f) identifying said aspirating cycle as acceptable or as not acceptable in dependency of a result of said checking.