DH 4.2 (build 4.0.1) spectrometer vs SpexFluoroMax spectrometer!

ABSTRACT

Accuracy and calibration testing for the DH 4.2 (build 4.0.1) homemade spectrometer and comparison against the SpexFluoroMax Fluorimeter

This is the first real test for the new cmos sensor in my spectrometer, so I decided to test its accuracy on a rhodamine b standard. The preparation has been explained in previous research notes, ref: http://publiclab.org/notes/dhaffnersr/05-02-2016/rhodamine-b-in-ethanol-study-may-02-2016

I used as my reference spectrum the original data for rhodamine b in ethanol from the Oregon medical laser center because it is a “true” spectra done with a scanning fluorimeter. My goal was to match the peak emission wavelength of rhodamine b in ethanol using my 532nm green laser as the excitation source; I also wanted to match the quantum yield of rhodamine b in ethanol at room temp (22 deg C.)

I used 6 different concentration standards, characterized by the control standard of 100ppb, the sample cuvette was filled with the control sample and each scan thereafter was added I drop per scan, equaling 6 drops for the final sample. The idea behind this was to find the concentration that would yield the correct result, my conclusion based on the evidence was that sample number 1, with 1 drop of rhodamine b @ 100ppm was the correct concentration.

The weight conversion per drop is: 100ppb= 0.025g/25microlitres 100ppm=0.039g/39microlitres. So subtracting 0.39g from 0.025g yields a difference of 0.014g/14microlitres of 100ppm is needed in a solution od 100ppb of rhodamine b in ethanol to achieve these results.

Experimental setup:

Reference (blank) Ethanol

Control sample: Rhodamine B in ethanol/100ppb

Excitation wavelength: 532nm (Aries green laser/20mW

2 semi-micro UV-Cuvette UV-transparent disposable/ 3ml capacity

1 cuvette for control sample

1 cuvette for samples 1 through 6/samples characterized by 1 through 6 drops of Rhodamine B in ethanol @ 100ppm

Instrumentation: DH 4.2 (build 4.0.1) homemade spectrometer

Processing software: spekwin32 hardware control prototype/version 172.2P4

Slit width: 0.40mm

Detector bandwidth: 4

Purpose of experiment: accuracy testing for new CMOS module in spectrometer (first series)