A method of determining a ratio of glycated hemoglobin to total hemoglobin in a whole blood sample, the method comprising the steps of: applying a whole blood sample on an upper surface of a blood separation membrane of a microfluidics device, the blood separation membrane having a lower surface that is associated with a first waste collection material, whereby red blood cells in the whole blood sample are captured on and/or in the blood separation membrane while plasma passes through the blood separation membrane and is wicked away from the blood separation membrane and into the first waste collection material; moving a portion of the microfluidics device so that the blood separation membrane is positioned over a negatively charged surface having a second waste collection material positioned therebelow and in association therewith; applying a lysing agent to the blood separation membrane, wherein the contents of the lysed red blood cells pass through the blood separation membrane and are brought into contact with the negatively charged surface, and wherein the negatively charged surface traps hemoglobin thereon and/or therein while the other components of lysed red blood cells are wicked away from the negatively charged surface and into the second waste collection material; moving a portion of the microfluidics device so that the negatively charged surface is positioned within an optical read chamber that allows for optical interrogation of the negatively charged surface by a spectrometer; spectroscopically measuring an amount of total hemoglobin on and/or in the negatively charged surface and an amount of one of glycated hemoglobin or non-glycated hemoglobin on and/or in the negatively charged surface; and determining a ratio of glycated hemoglobin to total hemoglobin in the whole blood sample based on the spectroscopic measurements. applying a whole blood sample on an upper surface of a blood separation membrane of a microfluidics device, the blood separation membrane having a lower surface that is associated with a first waste collection material, whereby red blood cells in the whole blood sample are captured on and/or in the blood separation membrane while plasma passes through the blood separation membrane and is wicked away from the blood separation membrane and into the first waste collection material; moving a portion of the microfluidics device so that the blood separation membrane is positioned over a negatively charged surface having a second waste collection material positioned therebelow and in association therewith; applying a lysing agent to the blood separation membrane, wherein the contents of the lysed red blood cells pass through the blood separation membrane and are brought into contact with the negatively charged surface, and wherein the negatively charged surface traps hemoglobin thereon and/or therein while the other components of lysed red blood cells are wicked away from the negatively charged surface and into the second waste collection material; moving a portion of the microfluidics device so that the negatively charged surface is positioned within an optical read chamber that allows for optical interrogation of the negatively charged surface by a spectrometer; spectroscopically measuring an amount of total hemoglobin on and/or in the negatively charged surface and an amount of one of glycated hemoglobin or non-glycated hemoglobin on and/or in the negatively charged surface; and determining a ratio of glycated hemoglobin to total hemoglobin in the whole blood sample based on the spectroscopic measurements.