QC2C- Spectrophotometry Instrumentation

UV-Vis Spectroscopy

measures absorbance, concentration and transmittance of a sample

UV-Vis Spectroscopy

standard method for determining the physical-chemical properties of drug molecules prior to formulation and for measuring release from formulations

Near IR

foods and food stuff

Medium IR

most important; widely organic molecule

Far IR

rotational spectra& crystal lattice vibrations

Group Frequency Region (GFR)

4000-1300cm-

GFR

more important, aid in identifying sample for IR interpretation. Functional group determination.

Fingerprint Region

1300-400cm-

FPR

Identify the sample due to carbon chain

KBr Pellet Technique

pressing the sample into salt

Nujol Mull Technique

suspension in mineral oil

Cast Film Technique

evaporated films on salt plates

Free Standing Films

casting or pressing the film

KBr Pellet Technique/ Salt Pellet Technique

for solids and powders

Cast Film Technique

for polymers and viscous liquids useful for sample that readily dissolves in a solvent which can be evaporated-off leaving a thin film behind

Mulling Technique

general sample handling technique (inexepensive), for samples that undergo ion exchange

Nujol

mulling agent: white HC mineral oil

Fluorolube

mulling agent: perfluoronated HC

Sealed cells

Liquid Sampling Technique: used for volatile liquids

Demountable cells

used for viscous material

Capillary film

suspending film of sample between two windows

Smear Technique

sample is spread over the surface or an IR window

Attenuated Total Reflectance (ATR)

uses a transmitting crystal for the analysis of bulk properties of solid and liquid samples (any form)

Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS)

IR energy is directed towards a sampling cup containing powdered or rough sample analysis for powder/matte samples

Specular Reflectance Fourier Transform Spectroscopy (SRIFTS)

allows thin coating layers on reflective

surfaces; analysis for samples of lubricating or polymeric coatings

IR Spectroscopy applications

Used for preliminary checking of the presence or absence of a carbonyl group which is difficult to check in other methods

Flame Spectroscopy

assay of metals with the use of acetylene as fuel

Flame Emission Spectrophotometry (FES)

identification is used by the color of flame that may produced for a specific element. Intensity of the emission energy is a function of the concentration of the elements being assayed. Corresponds to transitions from ground state

to a higher energy state

Monochromator/Filter

a narrow band of emitted radiation is selected

Detector

the intensity of the selected radiation is then measured using a photosensitive cell______

Flame Emission Spectrophotometry

Quantification of alkali metals and its salts and some alkaline earth metals and the determination of metallic impurities of some inorganic salts used in preparing solutions

Atomic Absorption Spectrophotometry (AAS)

Involves the measurement of light absorbed by metal ions

Hollow cathode lamp

Atomic Absorption Spectrophotometry (AAS) light source

more sensitivity

AAS advantage to FES

AAS

Determination of metal residues remaining from the manufacturing process in drugs and is only applicable to metallic elements

Fluorometry

Emission of light from a molecule where electronic energy has been propagated

Fluorometry

measures Transmittance; used in analysis of compounds that fluorescence

Fluorescence Spectrometry

other name for fluorometry

Collision deactivation and Luminescence

Ways used in fluorometry

Collision deactivation

aka non radiative process (fluorescence)

Luminescence

radiative process; emits light (phosphorescence)

Raman Spectroscopy

specimen under examination is irradiated with intense monochromatic light (usually laser light) and the light scattered from the specimen is analyzed for frequency shifts

Raman Spectroscopy

aka inelastic light scattering

Raman spectroscopy

Identification of complex samples

• provides additional fingerprint identity information complementary to mid-IR spectroscopy

Raman Spectro

specimen analyzed for frequency shifts

Light Scattering

the measurement of light scattered because of the substance’ microscopic optical density in homogenous of solutions or suspension

Nephelometry and Turbidimetry

Light scattering techniques

Nephelometry

based on the measurement of the brightness of the light reflected by a cloud of finely divided particles suspended in a liquid; Determination of Rheumatoid factor

Turbidimetry

based on the measurement of transmitted light by suspensions and colored samples

•measures turbidance and transmittance

Turbidimetry

Analysis of antibiotics, calcium pantothenate and Vit B12

Turbidimetry

Standardization of bacterial inoculum in bacterial assay

Visible region

region used in turbidimetry

Mass Spectroscopy (MS)

This is an analytical technique used to measure the mass-to-charge ratio of ions

•This find the composition of a physical sample by generating a mass spectrum representing the masses of sample components

Mass Spectroscopy (MS)

• This determines the molecular weight of an organic compound

• This is an analytical spectroscopic tool primarily concerned with the separation of molecular species according to their mass

Da (Dalton)

unit used in mass spectrometry

Mass Spectrometer

This is an Instrument that measures the masses of individual molecules that have been converted into ions.

Mass Spectroscopy (MS)

This provides specific method for determining or confirming the identity or structure of drugs and RM

Nuclear Magnetic Resonance (NMR)

This is the most powerful tool used for elucidating the structure of organic molecules.
•Determination of structural formula of an organic compound
•Diagnosis of Disease: MRI

Magnetic Fields

In NMR, transition between energy levels can be generated by radiant energy only if the molecules are placed in _______.

Nuclear Magnetic Resonance (NMR)

This uses radio frequency radiation.
This involves the nuclei of the compound
-Only nuclei with an odd sum of protons and neutrons have magnetic moments

Magnetic Resonance Imaging (MRI)

Instrument under NMR for disease diagnosis

2-15% w/w

In NMR, the sample must be pure and free from particulate matter and any magnetic contaminants ( where sample in solutions is: ____ w/w)

liquid or solid

NMR Analyte

CCl4, CS2, CDCl3

NMR Solvent

Tetramethylsilane (TMS)

NMR Reference Standard

Turbidimetry

light scattering where light is transmitted

Nujol

Mulling agent with white HC mineral oil

Fluorolube

Mulling agents perfluoronated HC

Attenuated Total Reflectance

ATR Meaning

analysis for powder/matt-samples

DRIFTS

SRIFTS

analysis fo sx of lubricating or polymetric coatings

acetylene

FES fuel

Neon or Argon

elements contained in the hollow cathode lamp