- Email: [email protected]
Easy analytical calculations and data publication with GKSoft graph
316
trends in analytical chemistry, vol. 9, no. lo,1990
Easy analytical calculations and data publication with GKSoft Graph G. Kraus TUbingen, Germany
Numerical data analysis, documentation and publishing of analytical results are facilitated by means of a new software package, GKSoft Graph, available on all Atari ST/MEGA computers with a minimum of 1 MByte memory capacity. The program was first developed for use in university research and was further improved to meet the demands of laboratory work. With a flexible interface to ASCII files, input of data from almost every measuring setup can be achieved simply. Manipulation, calculations and display are done using an interactive editor that employs the full well known GEM-facilities. Numerical data analysis is supported by a huge library of standard functions such as statistical tests (i.e., t-test, Kolmogorov’s test), smoothing facilities (i.e., Savitzky-Golay, cubic splines, B-splines, smoothing by convolution), numerical differentiation and integration using various algorithms and curve fitting by linear multivariate and non-linear techniques. The combination of a programmable calculator and function editor yields a very powerful tool for data manipulation. There is no apriori limitation to the amount of data analysed in one step (the limitation is given by the memory capacity of the computer system).
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200
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400
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600
I”“““‘,““““‘,““““‘,““““‘,““““‘,
0
10
20
30
40
50
’
time (mid Fig. 2. Changes in electric conductivity of a solid state CO-sensor.
linear
calibration
1.0-l
SIMS depth profile
104
The result is displayed in two or three dimensions. Using vector graphics output and data, high-quality publishing is possible with resolutions of up to 300 dpi on laser printers and 360 dpi on 24 pin matrix printers. In addition, drivers for HPGL colour-plotters are available. Integration of the graphics in word processing programs (i.e., SIGNUM) is quickly achieved for hard copy.
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loo0
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Sputter time(S) Fig. 1. SIMS depth profile analysis showing the change in the different ion-intensities with sputter time. The monitored masses are given in the illustration.
Fig. 3. Linear calibration showing the confidence region of the calibration line at 95% significance level.
317
trendsin analyticalchemistry, vol. 9, no. 10,199O
The editing and rearranging of graphics are carried out according to the habitual manner of data documentation. Headlines and additional text can be arranged in an arbitrary amount and at any position. Full documentation of every step in numerical data analysis is available on-line, both on screen as well as on printers and files. It is possible for all laboratory staff to perform routine work because every single step, from the capture of the data, its analysis
and graphical documentation, can be programmed in advance. References for every numerical algorithm are given in an extensive handbook. The illustrations (Figs. l-3) show examples of everyday laboratory work. Further information is obtainable from the author. Dr. Gerolf Kraus is at the Institute of Physical and Theoretical Chemistry, University of Tiibingen, Auf der Morgenstelle 8, W-7400 Tiibingen, Germany.
biotechnology focus
Flow-ELISA: Binding assays for process control Bo Mattiasson, Mats Nilsson, Per Berdbn and Hhkan HAkanson Lund, Sweden The combination of jlow injection analysis (FIA) and en.Zyme-linked immunosorbent assay (ELISA) gives a powerful immunoanalytical: technique that can be automated for bioprocess monitoring and control.
Introduction The desire to obtain high productivities in biotechnological processes has led to technical developments in at least three different directions: l process integration; l development of new reactor configurations to allow for operation at high catalyst densities; l process control through applications of specific biosensors as well as pattern recognition procedures. All these three approaches have demonstrated that much can be gained by proper design of the process. Furthermore, the different strategies can operate very well in synergy, e.g. process control may be applied with any of the other two approaches taken. A prerequisite for successful process control is to have access to suitable sensors. Biosensors have long been regarded as being potentially very useful; however they have only recently started to meet the expectations. This statement is valid for enzyme based sensors used for measuring low-molecular-weight 01659936/90/$03.00.
compounds; when it comes to determining macromolecules, fairly little has been achieved. A flow injection binding assay to quantify macromolecules in a continuous flow system was first introduced from our laboratorylP2. It was later modified to shorten the time for a cycle of analysis from 12 to 6 minutes3 and later to 70 seconds4. The present article deals with the development of a fully automated binding assay that is designed to meet the requirements for process control. When designing a binding assay to be used for process control a few questions arise: e.g. what is its analytical sensitivity? Does one have to sacrifice sensitivity for speed in analysis? If an intermittent assay is going to be used for monitoring a bioprocess, what is the frequency of analysis required? Is the stability of the immobilized affinity binding material sufficient? Is it sufficiently reproducible and reliable to be used as a signal for controlling a process? What are the molecules that can be measured with a sufficient accuracy? The present review is aimed at addressing some of these questions on the basis of what is known today about immunobased biosensors and other biosensors that exploit binding reactions. Many attempts have been presented in the last five years to design sensors based on biospecific recognition reactions. A broad spectrum of binding reactions have been tried in conjuction with construction of a biosensor. In this context, however, it should be mentioned that the dead end type of analysis, exemplified by traditional dip-stick technology, OElsevier
Science Pub1ishersB.V.
trends in analytical chemistry, vol. 9, no. lo,1990
Easy analytical calculations and data publication with GKSoft Graph G. Kraus TUbingen, Germany
Numerical data analysis, documentation and publishing of analytical results are facilitated by means of a new software package, GKSoft Graph, available on all Atari ST/MEGA computers with a minimum of 1 MByte memory capacity. The program was first developed for use in university research and was further improved to meet the demands of laboratory work. With a flexible interface to ASCII files, input of data from almost every measuring setup can be achieved simply. Manipulation, calculations and display are done using an interactive editor that employs the full well known GEM-facilities. Numerical data analysis is supported by a huge library of standard functions such as statistical tests (i.e., t-test, Kolmogorov’s test), smoothing facilities (i.e., Savitzky-Golay, cubic splines, B-splines, smoothing by convolution), numerical differentiation and integration using various algorithms and curve fitting by linear multivariate and non-linear techniques. The combination of a programmable calculator and function editor yields a very powerful tool for data manipulation. There is no apriori limitation to the amount of data analysed in one step (the limitation is given by the memory capacity of the computer system).
/ 0
”
I
200
”
,‘-I
400
/,I
600
I”“““‘,““““‘,““““‘,““““‘,““““‘,
0
10
20
30
40
50
’
time (mid Fig. 2. Changes in electric conductivity of a solid state CO-sensor.
linear
calibration
1.0-l
SIMS depth profile
104
The result is displayed in two or three dimensions. Using vector graphics output and data, high-quality publishing is possible with resolutions of up to 300 dpi on laser printers and 360 dpi on 24 pin matrix printers. In addition, drivers for HPGL colour-plotters are available. Integration of the graphics in word processing programs (i.e., SIGNUM) is quickly achieved for hard copy.
I
ma
‘,I
0
m-27AT
l
m-sss-
/
loo0
I,,
1zcJo
I ,’ 1400
Sputter time(S) Fig. 1. SIMS depth profile analysis showing the change in the different ion-intensities with sputter time. The monitored masses are given in the illustration.
Fig. 3. Linear calibration showing the confidence region of the calibration line at 95% significance level.
317
trendsin analyticalchemistry, vol. 9, no. 10,199O
The editing and rearranging of graphics are carried out according to the habitual manner of data documentation. Headlines and additional text can be arranged in an arbitrary amount and at any position. Full documentation of every step in numerical data analysis is available on-line, both on screen as well as on printers and files. It is possible for all laboratory staff to perform routine work because every single step, from the capture of the data, its analysis
and graphical documentation, can be programmed in advance. References for every numerical algorithm are given in an extensive handbook. The illustrations (Figs. l-3) show examples of everyday laboratory work. Further information is obtainable from the author. Dr. Gerolf Kraus is at the Institute of Physical and Theoretical Chemistry, University of Tiibingen, Auf der Morgenstelle 8, W-7400 Tiibingen, Germany.
biotechnology focus
Flow-ELISA: Binding assays for process control Bo Mattiasson, Mats Nilsson, Per Berdbn and Hhkan HAkanson Lund, Sweden The combination of jlow injection analysis (FIA) and en.Zyme-linked immunosorbent assay (ELISA) gives a powerful immunoanalytical: technique that can be automated for bioprocess monitoring and control.
Introduction The desire to obtain high productivities in biotechnological processes has led to technical developments in at least three different directions: l process integration; l development of new reactor configurations to allow for operation at high catalyst densities; l process control through applications of specific biosensors as well as pattern recognition procedures. All these three approaches have demonstrated that much can be gained by proper design of the process. Furthermore, the different strategies can operate very well in synergy, e.g. process control may be applied with any of the other two approaches taken. A prerequisite for successful process control is to have access to suitable sensors. Biosensors have long been regarded as being potentially very useful; however they have only recently started to meet the expectations. This statement is valid for enzyme based sensors used for measuring low-molecular-weight 01659936/90/$03.00.
compounds; when it comes to determining macromolecules, fairly little has been achieved. A flow injection binding assay to quantify macromolecules in a continuous flow system was first introduced from our laboratorylP2. It was later modified to shorten the time for a cycle of analysis from 12 to 6 minutes3 and later to 70 seconds4. The present article deals with the development of a fully automated binding assay that is designed to meet the requirements for process control. When designing a binding assay to be used for process control a few questions arise: e.g. what is its analytical sensitivity? Does one have to sacrifice sensitivity for speed in analysis? If an intermittent assay is going to be used for monitoring a bioprocess, what is the frequency of analysis required? Is the stability of the immobilized affinity binding material sufficient? Is it sufficiently reproducible and reliable to be used as a signal for controlling a process? What are the molecules that can be measured with a sufficient accuracy? The present review is aimed at addressing some of these questions on the basis of what is known today about immunobased biosensors and other biosensors that exploit binding reactions. Many attempts have been presented in the last five years to design sensors based on biospecific recognition reactions. A broad spectrum of binding reactions have been tried in conjuction with construction of a biosensor. In this context, however, it should be mentioned that the dead end type of analysis, exemplified by traditional dip-stick technology, OElsevier
Science Pub1ishersB.V.