L35 uv/is + fluorescence spectroscopy

what is spectroscopy

they are analytical techniques to measure the interactions of electromagnetic radiations within a sample

list the electromagnetic radiation from high energy to low energy

gamma rays→ x-rays → uv→ VIS→ microwaves→ radio waves(nmr)

what is an equation that relates energy to wavelength

what are subdivisions within uv

uva ( agin of skin and tanning) ,uvc( most dangerous due to high energy ), uvb ( causes sunburn )

what is the reason for most drugs appearing white

as they don’t absorb in the visible region

how does UV/VIS excite electrons and allows use to measure electronic transmissions

they use high energy light/ radiation

what does HOMO and LUMA stand for

highest occupied molecular orbital

lowest unoccupied molecular orbital

what is a chromophore

its the part of a molecule that is able to absorb UV/VIS

what are thypically chromophores

• double bonds ( pi-bonds)

• conjugated systems

• lone pairs of electrons

draw the structure of avobenzone and what does it absorb

what is the beer- lambert law

when considering the beer lambert law what is the relationship between the absorbance and the concentration

they are directly proportional to proportional to each other

what does uv/vis measure

absorbance

what does fluorescence measure and what are the two steps that are involved

it measures the emission of light

1. the sample absorbs light ( excitation )

2. it then emits the light as it relaxes to ground state ( emission )

explain why fluorescence is used to do things such as assays with enzymes ect

as fluorescence works with very low concentrations and its much more sensitive than uv/vis

what’s the criteria for a fluorescent tag that can be put on another compound/molecules

• same criteria as chromophore ( pi- bond, conjugated system, lone pair of electrons )

• ridged structure

what are two examples of applications of flourescence

1. spice- synthetic cannabinoid receptor agonist, it mimics THC which is found in cannabis. its extremely potent and can lead to seizures, strokes and death. fluorescence can be used to detect its compounds and provide information on its concentration

2. nitrazene- benzimidazole opioids, its a synthetic opioid that is more potent than heroin and can cause overdose, unpredictable side effects and death