The rema ining contents of the samples were transferred from the crucible to dried and cleaned volumetric flasks
The samples were transferred to 25ml volumetric flasks
, weighed and subsequently eliminated to fill the flask with distilled water.
The standard stock solution of praziquantel (100 [micro]g/mL) was used to prepare a set of diluted standard solutions of various concentrations (1-20 [micro]g/mL) prepared by pipetting appropriate volumes (0.1, 0.5, 1, 1.5, 2 mL) of stock solution into 10.0-mL volumetric flasks
and adjusting the volume to the mark with distilled water.
The temperature of the heating block was maintained at 360 (o)C for 2 h after which the samples were left to cool and transferred into a 50ml volumetric flasks
and the sample volume made to the mark by adding deionized.
Unfortunately, this is not as useful for NIRS; it is a carryover form HPLC protocol, where samples are made with analytical balances and volumetric flasks
. The solutions are run in standard cuvettes and all parts of Beer's law apply: constant, known pathlength, no interaction between analyte and matrix (solvent), no Absorbance of the light by the matrix, etc.
Aliquots of working solutions corresponding to 50-500 [micro]g/mL and 25-250 [micro]g/mL of TRG and TAD, respectively, were added separately into a series of 10 mL volumetric flasks
and completed to volume with methanol.
Beakers, graduated cylinders, and volumetric flasks
were used for the accurate preparation of the titrant, indicator, and buffers.
(6) Cylindrical stainless steel volumetric flasks
were used (100 mm in diameter, 650 mm in height).
Serial dilutions were prepared from the stock solution of hydrocortisone reference standard (1 mg/ml) by pipetting 8.0 ml, 4.0 ml, 2.0 ml, 1.6 ml, 0.8 ml, and 0.4 ml of the stock solution into separate 20 ml volumetric flasks
. The solutions were made up to volume with the diluent and mixed thoroughly.
The mixture was heated at 100 degC for 20 minutes on water bath and after cooling transferred to volumetric flasks
and made the volume up to 10 mL with distilled water.
Workflows to prepare samples manually using volumetric flasks
have not changed significantly in nearly 100 years.