3 replies to this topic

[ennyk]

Can anyone advice how we calibrate the statfax. FYI we are using this for testing Histamine quantity and we calibrate this by running the known standard as sample and obtain the figures as results for calibration. refer to the result attached. Can anyone advice on how we interpret these results that does not match the standard figures (i.e. 0,25,50,100) and what the corrective action for this?

 

Thanking you in advance.

[Charles.C]

Can anyone advice how we calibrate the statfax. FYI we are using this for testing Histamine quantity and we calibrate this by running the known standard as sample and obtain the figures as results for calibration. refer to the result attached. Can anyone advice on how we interpret these results that does not match the standard figures (i.e. 0,25,50,100) and what the corrective action for this?

 

Thanking you in advance.

 

Hi ennyk,

 

No attachment.

Numbers have no units,

 

Does the machine not come with a manual ?

[ennyk]

Hi Charles; 

Below is what the manual stated. We tried and do with known concentrations. It does not state if there is any variations or which figures that we will consider the machine to be invalid.

 

See Section 2.5.4 – Cubic Spline Mode accepts a

number of calibrators and calculates concentrations

based on the Cubic Spline (constrained) calibration

curve.

Stat Fax® 4700 accepts a number of Calibrators and

calculates concentrations based on the Cubic Spline

(Constrained) calibration curve. Calibrator materials of

known concentrations are used to calibrate the Stat

Fax® 4700 so that concentrations of unknown

Samples are calculated from the generated curve. The

resulting calibrator curve is a smooth curve connecting

the Calibrator points, which may be entered in

ascending or descending order of absorbance. A

constraining algorithm is applied to prevent curve

overshoot.

Attached Files

•  160821-STATFAX CALIBRATION.pdf   248.43KB   6 downloads

[Charles.C]

 

Hi Charles; 

Below is what the manual stated. We tried and do with known concentrations. It does not state if there is any variations or which figures that we will consider the machine to be invalid.

 

See Section 2.5.4 – Cubic Spline Mode accepts anumber of calibrators and calculates concentrationsbased on the Cubic Spline (constrained) calibrationcurve.

Stat Fax® 4700 accepts a number of Calibrators andcalculates concentrations based on the Cubic Spline(Constrained) calibration curve. Calibrator materials of known concentrations are used to calibrate the StatFax® 4700 so that concentrations of unknownSamples are calculated from the generated curve. Theresulting calibrator curve is a smooth curve connectingthe Calibrator points, which may be entered inascending or descending order of absorbance. Aconstraining algorithm is applied to prevent curve

overshoot.

 

 

Hi ennyk,

 

I'm not personally familiar with this instrument but I'm not sure I understand yr specific problem ?

 

Yr extract explains how the calibration curve is generated for the Cubic spline mode . The results should apparently be obtained as per this mode or the alternative preceding modes as listed in the manual, ie. -

 

 mode of operation.PNG   142.27KB   0 downloads

 

I noted this introductory manual comment  which is the traditionally suggested option in case of operational difficulties -

 

It is a general purpose instrument intended to be used by trained laboratory professionals who are capable of selecting the appropriate features and options for each specific clinical application. Contact your company’s instrument service provider to arrange for training if the information in this manual is not sufficient.