MOLBIO LAB: TOPIC 1

TO CONTAIN

TO DELIVER

TWO TYPES OF PIPETTE

TO CONTAIN

Holds or dispenses a particular volume but DOES NOT dispense the EXACT VOLUME.

TO CONTAIN

TO DELIVER

TWO TYPES OF PIPETTE

TO CONTAIN

Holds or dispenses a particular volume but DOES NOT dispense the EXACT VOLUME.

TO DELIVER

Holds a particular volume of liquid which when allowed to flow by gravity will deliver THE EXACT VOLUME.

TO CONTAIN

Must be rinsed out to complete an accurate transfer to the solution to be delivered.

TO DELIVER

Does not require rinsing

TO BLOWOUT

Has a continuous etched ring or two small close continuous rings (located near the pipette’s mouth)

TO DRAIN

It does not have etched ring

GRADUATED PIPETTE

“Serological Pipettes”

Has graduation marks up to the tip.

A type of blow out pipette.

MOHR PIPETTE

It does not have marks up to the tip.

A type of self-draining pipette

MACROPIPETTE

Dispenses volume greater than 1mL

MICROPIPETTE

It is calibrated to contain a volume of less than 1mL.

A type of TC pipette

BURETTE PIPETTE

Contains a valve/stopcock used to start and stop the flow of solution. Used for titration or dispensing aliquots of a solution.

VOLUMETRIC PIPETTE

A long narrow tube with an elongated / rounded bulb near the middle.

VOLUMETRIC PIPETTE

For NON VISCOUS FLUID (watery)

VOLUMETRIC PIPETTE

Has the highest degree of accuracy and precision. Deliver an exact volume of fluid. Self draining.

OSTWALD FOLIN PIPETTE

Specialized version of volumetric pipette. It is shorter; the bulb is near the delivery tip. The tip is larger for faster draining.

BLOW OUT PIPETTE

OSTWALD FOLIN PIPETTE IS A TYPE OF

PASTEUR PIPETTE

These are disposable pipettes. It does not have graduation marks.

PASTEUR PIPETTE

It is used to transfer solutions or biological fluids without consideration of a specific volume.

AUTOMATIC PIPETTE

These are common pipettes. It is rapid and repetitive measurements.

AUTOMATIC PIPETTE

mechanism that draws and dispenses the liquid in an integral part of the pipette,

GRADUATION MARKS

all the LINES in the volumetric glasswares.

CALIBRATION MARKS

all the DESIGNS (e.g letters or numbers) in volumetric glassware.

CLEAR OR COLORLESS

read at the lower meniscus

TURBID OR COLORED

read at the upper meniscus

PARALLAX ERROR

All reading must be with the eye on level with the menisucs to avoid ____ (error by positions)

AIR DISPLACEMENT

Relies on a position for suction. It has disposable tips.

DOWN

When push-button is pressed = piston inside the instrument moves ____ to let air out

LIQUID ASPIRATED

The volume of air displacement is equivalent to the volume of ___

POSITIVE DISPLACEMENT

Works like a syringe. Much like a hypodermic needle. For suction

POSITIVE DISPLACEMENT

It does NOT REQUIRE disposable tips but requires calibration

REVERSE PIPETTING

Performed when dispensing viscous / foaming liquids. Or when dispensing a very minute amount of liquid.

FORWARD PIPETTING

Performed when dispensing aqueous solutions. Which may contain low detergents and protein concentration.

RATIO

The number of units of solute to the number of units of solvent. It is always expressed as colon.

RATIO

SOLUTE: SOLVENT

DILUTION

Number of units of solute to the number of units of solution.

DILUTION

SOLUTE : SOLUTION

SIMPLE DILUTION

A concentrated solution is mixed with a diluent in a single step to achieve a lower concentration. It follows the formula C1V1 = C2V2 to determine final conc.

SERIAL DILUTION

Each subsequent dilution uses a portion of the previous diluted solution. It is performed in equal ratios (1:2, 1:10)