Lecture 1 - Introduction Principles of Laboratory Analysis PDF

Introduction to Principles of Laboratory Analysis MLS 2100 LECTURE 1 Concept of Solute and Solvent ◼ Many analyses in the clinical laboratory are concerned with the determination of the presence of or measurement of the concentration of substances in solutions. ◼ Most often being: ◼ Blood...

Introduction to Principles of Laboratory Analysis MLS 2100 LECTURE 1 Concept of Solute and Solvent ◼ Many analyses in the clinical laboratory are concerned with the determination of the presence of or measurement of the concentration of substances in solutions. ◼ Most often being: ◼ Blood ◼ Serum ◼ Urine ◼ Spinal fluid Concept of solute and solvent ◼ What is a solution?  Concept of solute and solvent ◼ A solution is a homogeneous mixture of one or more solutes dispersed molecularly in a sufficient quantity of a dissolving solvent. ◼ In laboratory practices, solutes are typically measured and are frequently referred to as analytes. Expressing Concentrations of Solutions Equations for Expression of Concentration ◼ Molarity (M)Molarity is the number of moles of solute per liter of solution. ◼ 𝑀 = 𝑛 solute / 𝑉 solution ◼ Where: ◼ M = molarity (mol/L) ◼ 𝑛 solute = moles of solute (mol) ◼ V solution = volume of the solution (L) Equations for Expression of Concentration ◼ Molality (m)Molality is the number of moles of solute per kilogram of solvent. ◼ 𝑚 = 𝑛 solute / 𝑚 solvent ◼ Where: ◼ 𝑚 = molality (mol/kg) ◼ 𝑛 solute = moles of solute (mol) ◼ 𝑚 solvent = mass of the solvent (kg) Equations for Expression of Concentration ◼ Mass Percent (w/w%)Mass percent is the mass of solute divided by the total mass of the solution, multiplied by 100. ◼ Mass Percent=(𝑚solute / 𝑚solution)×100 ◼ Where: ◼ 𝑚 solute = mass of the solute (g) ◼ 𝑚 solution = mass of the entire solution (g) Equations for Expression of Concentration Volume Percent (v/v%) ◼ Volume percent is the volume of solute divided by the total volume of the solution, multiplied by 100. ◼ Volume Percent=(𝑉solute / 𝑉solution)×100 ◼ Where: ◼ 𝑉solute = volume of the solute (mL or L) ◼ 𝑉solution = total volume of the solution (mL or L) Equations for Expression of Concentration ◼ Mole Fraction (X)Mole fraction is the ratio of the number of moles of one component to the total number of moles in the mixture. ◼ 𝑋𝐴=𝑛𝐴 / (𝑛𝐴+𝑛𝐵) ◼ Where: ◼ 𝑋𝐴 = mole fraction of component A ◼ 𝑛𝐴 = moles of component A ◼ 𝑛𝐵 = moles of component B Equations for Expression of Concentration ◼ Normality (N)Normality is the number of equivalents of solute per liter of solution. ◼ 𝑁=equivalents of solute / 𝑉solution ◼ Where: ◼ 𝑁 = normality (eq/L) ◼ 𝑉solution = volume of the solution (L) Reference material ◼ What are reference standard materials? ◼ Why is it important? Reference material ◼ A reference-standard material is commonly defined as a "highly purified compound that is well characterized", accordingly, the quality and purity of reference standards are crucial to determining scientifically valid results for many pharmaceutical analytical methods. Basic techniques and procedures Qualitative vs Quantitative Analysis