Quantification of unknown nanoscale biomolecules using the average-weight-difference method

In order to quantify the amount of drug molecules in drug delivery systems, analytical techniques such as high-performance liquid chromatography are used due to their accuracy and reliability. However, the instruments required for such techniques are expensive and not available in all laboratories. Therefore, in this study, we introduce a method that can be a relatively inexpensive and easy to perform drug analysis in almost any laboratory set-up. We have devised the "average-weight-difference method" within the limits of existing spectral analyses. By employing this method, we quantitatively analyzed the amount of isoniazid or doxorubicin molecules loaded onto β-glucan nanoparticles. This proved to be a relatively simple and reliable method and can be used to estimate the amount of nanoscale biomolecules before their analysis through expensive equipment in an environment where the instruments are not readily available.