Medicines quality Flashcards
(14 cards)
How are melting point assays used
The melting point assay is a fundamental physical test used to determine the purity and identity of a substance.
How is polarimetry used
Polarimetry measures the interaction between a compound and plane polarized light. It is particularly useful for analyzing chiral structures.
What do chiral compounds do
Chiral compounds can rotate the plane of polarized light:
What is the equation for measuring specific rotation
The specific rotation of a substance can be calculated using the formula:
[α] = α / (l * c)
α = observed optical rotation
l = optical path length in dm
c = concentration in g/ml
How does the refractive index work
The refractive index is a measure of how light bends when entering a substance. A refractometer is used to measure this property, which has applications in Total Parenteral Nutrition (TPN) and pharmaceutical excipients.
Calculate the specific rotation of glyceraldehyde from the following data: 2g of (+)-glyceraldehyde in 10ml of water, rotation of 1.74° at 25°C in a 100 mm polarimetry tube.
calculate
What is UV spectroscopy used for
Quantification of drugs in formulations
Determining pKa values
Monitoring drug release and degradation
Identity checks in pharmacopoeia
What is the beer lambert law
The Beer-Lambert Law relates absorbance to concentration:
A = A(1%, 1cm) * c
A = measured absorbance
A(1%, 1cm) = absorbance of a 1% w/v solution in a 1 cm cell
c = concentration in g/100ml
Example beer lambert calc
Answer
What are the spectra ranges for different groups
Hydroxyl groups (3400-3200 cm-1)
Carbonyl groups (1850-1630 cm-1)
Double bonds (around 3000 cm-1)
Triple bonds (2200-2050 cm-1)
What does the index of hydrogen deficiency do
The IHD helps determine the presence of multiple bonds and rings in a molecular formula:
Double bond or ring = 1 IHD
Triple bond = 2 IHD
What is infared spectroscopy used for
Infrared spectroscopy is used for:
Identifying raw materials
Characterizing compounds in solid and semi-solid states
Fingerprint tests for films and packaging
What are the applications of TLC in pharmacy
Identification of known and unknown impurities
Limit tests for drug quality
TLC is essential for detecting organic impurities in active pharmaceutical ingredients (APIs).
Sample MCQ: During quality control of paracetamol tablets, which technique is most appropriate for monitoring organic synthesis impurities?
Infra-Red spectroscopy
Optical Rotation
Thin layer chromatography
Melting
TLC
