Laboratory Equipment and Supplies Flashcards
tolerates heating and sterilization for lengthy periods; subject to scratching and may cloud with strong alkali
borosilicate (pyrex, kimax)
6x stronger than borosilicate; better able to resist scratching and alkali
aluminosilicate (corex)
heat, chemical, and electrical tolerance and excellent optical properties; used for high thermal, drastic shock, and extreme chemical treatment with acids and alkali
high silica (vycor)
boron-free glass; used with strong acids and alkali
soft glass
soda lime glass; most inexpensive; releases alkali causing errors in certain pH determinations
flint glass
reduces light transmission
low actinic glass (amber-colored glass)
borosilicate, aluminosilicate, high silica
a. ↑ thermal resistance
b. ↓ thermal resistance
a. ↑ thermal resistance
soft glass, flint glass
a. ↑ thermal resistance
b. ↓ thermal resistance
b. ↓ thermal resistance
excellent temp tolerance and chemical resistance
teflon
used for pipet tips, test tubes, for cryogenic procedures (↓ temp.)
polypropylene
stronger than polypropylene; used for centrifuge tubes, graduated cylinders
polycarbonate
used for disposable transfer pipets, test tubes, bottles (binds/absorbs dyes, proteins, picric acids)
polyethylene
rigid, clear; used for test tubes, graduated tubes
polystyrene
soft, flexible but porous; frequently used as tubing
polyvinyl chloride
teflon, polypropylene, polycarbonate
a. autoclavable, ↑ thermal resistance
b. non-autoclavable, ↓ thermal resistance
a. autoclavable, ↑ thermal resistance
polyethylene, polystyrene, polyvinyl chloride
a. autoclavable, ↑ thermal resistance
b. non-autoclavable, ↓ thermal resistance
b. non-autoclavable, ↓ thermal resistance
glass pipettes:
HOLDS but does not deliver the exact volume
to contain
glass pipettes:
DELIVERS the exact volume it holds
to deliver
glass pipettes:
etched ring/band near the mouth
blow-out pipet
allowed to drain by GRAVITY
self-draining pipet
example of blow-out pipettes with etched ring band
Ostwald-Folin
Serologic
example of self-draining pipettes
Volumetric
Mohr
Volumetric, Ostwald-Folin: what type?
a. transfer pipettes
b. measuring/graduated pipettes
a. transfer pipettes
Serologic, Mohr: what type?
a. transfer pipettes
b. measuring/graduated pipettes
b. measuring/graduated pipettes
graduated to tip
Serologic
(si SERologic ay GRUMADUATE)
graduated between 2 marks/ no graduation to tip; point to point delivery
Mohr
(di pa grumaduate, kaya MOHR aral)
Semi-automatic micropipettors:
uses SUCTION to draw sample into a disposable polypropylene tip; piston does not come in contact with liquid
air displacement
Semi-automatic micropipettors:
- operates like a hypodermic syringe (piston, plunger)
- no air cushion
- for high density and very viscous
- used for sampling in most discrete automated systems
positive displacement
Calibration for semi-automatic micropipettors:
how frequent?
6 mos
Calibration for semi-automatic micropipettors:
Gravimetric method- weight of ____ delivered; most accurate
distilled water
(d= 1g/mL @20degC)
Calibration for semi-automatic micropipettors:
Spectrophotometric method - absorbance of ____ and ____ delivered
potassium dichromate
para-nitrophenol
Centrifuges:
tubes attain a HORIZONTAL position during spinning, vertical when at rest
Horizontal or swinging bucket
Horizontal or swinging bucket rpm?
3,000 rpm
Centrifuges:
tubes are at FIXED ANGLE when rotating
Fixed-angle or angle head
Fixed-angle or angle head rpm?
7,000 rpm
Centrifuge:
used TO SEPARATE LAYERS of different specific gravities; usually refrigerated to counter the heat produced due to friction
ultracentrifuge
Ultracentrifuge rpm?
10,000 rpm
Centrifuge:
for body fluid CELL COUNTS
cytocentrifuge
Cytocentrifuge rpm?
200-2,000 rpm
Units used to centrifuges
rpm
Relative Centrifugal Force (g)
Svedberg (s)
Formula for converting rpm to RCF:
RCF(g) = 1.118x10^-5 x (r) in cm x rpm^2
centrifuge QC parameters
timer, stopwatch
speed - tachometer/strobe light
thermometer (for refrigerated centrifuge)
centrifuge QC frequency?
every 3 mos (quarterly)
