Paraformaldehyde, EM Grade, Purified

(Polyoxymethylene)
OH(CH₂O)_n H   F.W. Average: 600   CAS #30525-89-4

Prill	19200
Granular	19208 19210

Paraformaldehyde is the condensation product of methylene glycol, a substance not so far isolated in its pure form; it is a white solid with a formaldehyde content between 78 and 98% and is supplied either as a Prill or Granular. All forms contain more than 95.5% paraformaldehyde content. The Prill and Granular forms are small, free-flowing, dust-free beads, the most desired by EM users. A fast-penetrating EM fixative used in combination with Glutaraldehyde, Acrolein, and Osmium Tetroxide. Karnovsky, M.J., J. Cell Biol., 27, 137A (1965). Hayat, M.A. Principles & Tech., of EM (Univ. Park Press), 68 (1981)

RT	19200	Prill	500g	11.00
RT	19202	Prill	kilo	17.00
RT	19208	Granular	500g	11.00
RT	19210	Granular	kilo	17.00

Technical Tip

Paraformaldehyde Static Jumps

Paraformaldehyde Aqueous Solution -16% (Formaldehyde Aqueous Solution, 16%)

CAS #30525-89-4
Prepared from Paraformaldehyde crystal, 16% aqueous solution, methanol free. Microfiltered and stored in pre-scored ampoules.

RT	15700	16% Paraformaldehyde (formaldehyde) aqueous solution	10ml	5.00
RT	15710	16% Paraformaldehyde (formaldehyde) aqueous solution	10x10ml	22.50
RT	15711	16%Paraformaldehyde (formaldehyde) aqueous solution, same as 15710	10bxs/lot	210.00

We can prepare in accordance to your special requirements (any concentration desired). Call for more information.

See Formaldehyde Solution, for other standard concentrations.

Paraformaldehyde-Glutaraldehyde Solution Karnovsky's Fixative

Ready To mix. Kit consists of: 2x10ml ampoules 16% Formaldehyde1x10ml ampoules 50% Glutaraldehyde1x50ml 0.2M Sodium Phosphate Buffer

0-5ºC	15720		1 kit	17.00
0-5ºC	15730		Lot of 5 kits	76.50

Paramat and Paramat Extra

Please see listing in Embedding Media for Histology and Light Microscopy.

Tissue-TEK Paraffin

Please see listing in Embedding Media.

Paraplast Embedding Medium

Paraplast X-tra

Handy pellet form melts rapidly. Melting Point 53-54°C. Cuts to 2 micron thickness with exceptional ribbon continuity. Extra compression resistance provides total support of tissues

RT	19214	Paraplast X-tra	1 kilo	13.75
RT	19215	Paraplast X-tra	8 kilo	90.00

Paraplast Plus

Reduces infiltration time by one-third. Cuts to 2 micron thickness with excellent ribbon continuity. Convenient pellet form melts rapidly. Melting point 56°C. Double filtered. No need for filtration before use.

RT	19216	Paraplast Plus	1 kilo	12.75
RT	19217	Paraplast Plus	8 kilo	83.50

Paraplast Medium

Handy pellet form melts rapidly. Melting Point 56°C
Cuts to 4 micron thickness with excellent ribbon continuity - no Crumbling or cracking.
Double filtered. No need for filtration before use.

RT	19218	Paraplast Medium	1 kilo	11.00
RT	19219	Paraplast Medium	8 kilo	77.00

Paraffin Waxes

For a continuation of our Paraffin Waxes, please see listing in Embedding Media.

Articles of Interest

Re-Embedding of Paraffin Embedded Specimens in Resin

Paraffin - Peel-A-Way® Embedding Wax

For our complete line of Embedding Waxes, please see Embedding Media for Histology and Light Microscopy

PEG - GMA/PEG Embedding Kit,

Please see listing in Embedding Media Kits.

Parlodion (Pyroxylin Purified Strips)

C₁₂H₁₆N₄O₁₈   F.W. 504.28   CAS #9004-70-0
Highly purified from cellulose nitrate; specially prepared for embedding tissue for sectioning and for preparing semi-permeable membranes.

RT

19220

10g

50.00

Parlodion 2% in Amyl Acetate

See Collodion, 2% .

Periodic Acid, Reagent

H₅IO₆   F.W. 227.96   CAS #10450-60-9

Assay		>99.0%
Heavy Metals		.0.005%
Insoluble Matters		0.01%
Iron		.0.003%
Other Halogen (Cl)		0.01%
Residue after Ignition		0.01%
Sulfate		0.01%

Used as a Fixative: Issidorides, M.R., and Kasorchis, T. (1981).
Dispersed and compact chromatin demonstrated with a new EM Method: phosphotungstic acid-hematoxylin block-staining. Histochemistry 73,21
Used widely as a Negative Stain:

• As Spray method: Horne, R.W., and Pasquali-Ronchette, I. (1974). A negative staining-carbon film technique for studying viruses in the electron microscope.
• Preparation procedures for examining icosahedral and filamentous viruses. J. Ultrastruct. Res. 47, 361. Locke, M., and Kirhman, N. (1971).
• Hot Alcoholic phosphotungstic acid and uranyl acetate as routine stains for thick and thin sections. J. Cell Biol., 50, 550., Farragiana, T., and Marinozzi, V. (1979).
• Phosphotungstic acid staining of polysaccharides containing structures on epoxy embedded tissues. J. Submicrosc. Cytol. 11, 263.Bloom, E.E., And Aghajanian, G.K. (1968).
• Fine structural and cytochemical analysis of the staining of synaptic junctions with PTA. J. Ultrastruct. Res. 22, 261

RT

19325

25 g

32.00

Periodic Acid Solutions

Please see listing in Reagents for Histology

Permount™ Mounting Medium

Please see listing in Adhesives and Mountants

Phenol Red

(Phenolsulfonphthalein)
C₁₉H₁₄O₅S   F.W. 354.38   CAS #143-74-8
A standard indicator for preparing buffers, pH range 6.4-8.2.

RT

19327

5 g

17.00

Phenol Red Sodium Salt

(Phenolsulfonphthalein Sodium Salt)
C₁₉H₁₃NaO₅S   F.W. 376.37    CAS #34487-61-1
A standard indicator for preparing buffers, pH range 6.8-8.2.

Assay		>99.0%
Water		<0.1%

RT

19328

5 g

26.00

(PMSF), Phenylmethylsulphonyl Fluoride

C₆H₅CH₂SO₂F   F.W. 174.20   CAS #329-98-6

Assay		>99.0%
Water		<0.1%

RT	19330		1g	19.00
RT	19331		5g	90.00

Phosphate Mixed Sodium Salts 0.2 M Buffer

Please see listing in Prepared Buffers.

RT	11600-05		1g	17.00
RT	11600-10		5g	26.00

Phloxine B, Certified, C.I. #45410

(Acid Red 92; Cyanosine; Eosin 10B; Phloxine TA, N, BP Super, RB, TB, or BB)
C₂₀H₂O₅Cl₄Br₄Na₂   F.W. 829.66   CAS #18472-87-2
Solubility: 10.5% Water; 5.0% Alcohol; 9.0% Cellosolve; 4.5% Glycol; 0.0% Xylene

RT

19350

25 g

35.00

Phosphomolybdic Acid, Crystal, Reagent, A.C.S.

(dodeca-Molybdophosphoric Acid)
H₃PO₄·12(MoO₃)·24H₂O   F.W. 2257.6   CAS #51429-74-4

RT

19400

100g

85.00

Phosphomolbdic Acid Solutions

Please see listing in Reagents for Histology

Phosphotungstic Acid, Crystal, Reagent, Highest Purity

(Tungstophosphoric Acid)
H₃[P(W₃O₁₀)₄]   aq F.W. 2880.17+aq   CAS #12501-23-4
Specifications:

Solubility		Practically clear, colorless solution.
Ammonia (NH )		0.004%
Chloride (Cl)		0.03%
Insoluble Matter		0.02%
Nitrate (NO3 )		0.004%
Sulfate (SO4 )		0.005%
Heavy Metals and Iron.		No color formation on addition of Hydrogen Sulfide

Used as a Fixative:

Issidorides, M.R., and Kasorchis, T. (1981).
Dispersed and compact chromatin demonstrated with a new EM Method: phosphotungstic acid-hematoxylin block-staining. Histochemistry 73,21

Used widely as a Negative Stain:

• As Spray method: Horne, R.W., and Pasquali-Ronchette, I. (1974). A negative staining-carbon film technique for studying viruses in the electron microscope.
• Preparation procedures for examining icosahedral and filamentous viruses. J. Ultrastruct. Res. 47, 361. Locke, M., and Kirhman, N. (1971).
• Hot Alcoholic phosphotungstic acid and uranyl acetate as routine stains for thick and thin sections. J. Cell Biol., 50, 550.,Farragiana, T., and Marinozzi, V. (1979).
• Phosphotungstic acid staining of polysaccharides containing structures on epoxy embedded tissues. J. Submicrosc. Cytol. 11, 263.Bloom, E.E., And Aghajanian, G.K. (1968).
• Fine structural and cytochemical analysis of the staining of synaptic junctions with PTA. J. Ultrastruct. Res. 22, 261

RT

19500

100g

52.00

Phosphotungstic Acid Solutions

Please see listing in Reagents for Histology

Picric Acid, Reagent, Crystal, A.C.S.

(2,4,6-Trinitrophenol)
C₆H₂(NO₂) ₃OH   FW 229.11   CAS #88-89-1
A.C.S. Specifications:

Water		min 30%
Melting Point (dried)		121-123°C
Insoluble in Resinous Matter.		0.01%
Insoluble in benzene		0.1%
Sulfate		0.01%

RT

19550

100g

49.50

Picric Acid Solutions

Please see listing in Reagents for Histology

Pipes to Ruthenium