Abstract
In connection with the potential development of automatic two-wavelength microspectrophotometry, a new version of the two-wavelength method has been formulated. Unlike its predecessors, the Ornstein and Patau versions, the new method varies the area of the photometric field seeking to maximize a relationship between distributional errors at the two wavelengths. Stating this distributional error relationship in conventional photometric terms, the conditions at the maximum are defined by taking the first derivative with respect to field size and setting it equal to zero. This operation supplies two equations; one relates the transmittances at the two wavelengths, and a second states the relative amount of chromophore in the field in terms of transmittance at one wavelength. With the first equation to drive a servomechanism which sets the appropriate field size, the desired answer can then be obtained directly and continuously from the second equation. The result is identical in theory with those of the earlier methods, but the technique is more suitable for electronic computing.
Full Text
The Full Text of this article is available as a PDF (231.5 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- MENDELSOHN M. L., RICHARDS B. M. A comparison of scanning and two-wavelength microspectrophotometry. J Biophys Biochem Cytol. 1958 Nov 25;4(6):707–709. doi: 10.1083/jcb.4.6.707. [DOI] [PMC free article] [PubMed] [Google Scholar]
- MENDELSOHN M. L. The two-wavelength method of microspectrophotometry. II. A set of tables to facilitate the calculations. J Biophys Biochem Cytol. 1958 Jul 25;4(4):415–424. doi: 10.1083/jcb.4.4.415. [DOI] [PMC free article] [PubMed] [Google Scholar]
- ORNSTEIN L. The distributional error in microspectrophotometry. Lab Invest. 1952;1(2):250–265. [PubMed] [Google Scholar]
- PATAU K. Absorption microphotometry of irregular-shaped objects. Chromosoma. 1952;5(4):341–362. doi: 10.1007/BF01271492. [DOI] [PubMed] [Google Scholar]