Purification of glutaraldehyde by vacuum fractional distillation

Purification of glutaraldehyde by vacuum fractional distillation

Abstracts of The Netherlands Society of Electron Microscopy Annual Meeting s i s t i n g of f l a t t e n e d s u p e r f i c i a l c e l l s , are w ...

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Abstracts of The Netherlands Society of Electron Microscopy Annual Meeting s i s t i n g of f l a t t e n e d s u p e r f i c i a l c e l l s , are w e a k l y s t a i n e d . T a n n i c acid c o u l d n o t b e d e m o n s t r a t e d o n t h e s u r f a c e o f the c a r c i n o m a in s i t u c e l l s and the i n v a d i n g squamous carcinoma cells. It s e e m s t h a t s u r f a c e s t a i n i n g w i t h t a n n i c a c i d is a p r o m i s i n g a p p r o a c h i n d i s c r i m i n a t i n g n o r m a l , p r e - m a l i g n a n t and malignant ectocervical epithelia. 1.

P. Kenemans et al. in Biology of the Cancer Cell, ed. K. Letnansky (Kugler Publ., Amsterdam, 1980). 2. J. H. M. Davina et al., Scanning Electron Microscopy, vol. 3, pp. 37-48 (1981). 3. V. Mizuhira et al., Acta Histochem. Cytochem. 5 (1972) 233-36. Supported by the Dutch Cancer Society (number NUKC-SMM 79~7)

in an o i l b a t h . The f i r s t d i s t i l l a t e , c o l l e c t e d a t a t e m p e r a t u r e o f 2 0 ° C to 40°C in a b o u t two h o u r s a n d c o n t a i n i n g i m p u r i t i e s , was d i s c a r d e d . S u b s e q u e n t l y , the p u r i f i e d g l u t a r a l d e h y d e w i t h a Pi < 0 . 2 0 w a s c o l l e c t e d at a t e m p e r a t u r e o f 8 0 o c in a b o u t o n e - a n d - a - h a l f h o u r s . i. 2. 3.

P U R I F I C A T I O N OF G L U T A R A L D E H Y D E B Y VACUUM FRACTIONAL DISTILLATION D i j k , J. A. O o s t e r b a a n , E. H u l s t a e r t C e n t r e for M e d i c a l E l e c t r o n M i c r o s c o p y , U n i v e r s i t y of G r o n i n g e n , G r o n i n g e n , The N e t h e r l a n d s

The e m p l o y m e n t of m o n o m e r i c g l u t a r a l d e h y d e as a f i x a t i v e is a d v a n t a g e o u s f o r e n z y m e c y t o c h e m i s t r y as t h e e n z y m e a c t i v i t y is b e t t e r r e t a i n e d t h a n w i t h p o l y m e r ic g l u t a r a l d e h y d e . I F a h i m i and D r o c h m a n s 2 d e v e l o p e d a m e t h o d to o b t a i n m o n o m e r i c g l u t a r a l d e h y d e by d i s t i l l a t i o n . A c c o r d i n g to t h e i r m e t h o d the g l u t a r a l d e h y d e s o l u t i o n h a d to b e d i s t i l l e d t w i c e in o r d e r to o b t a i n a h i g h c o n c e n t r a t i o n of m o n o m e r s . We h a v e d e v e l o p e d a m e t h o d w h i c h y i e l d s a h i g h c o n c e n t r a t i o n of m o n o m e r s a f t e r o n l y one d i s t i l l a t i o n . T h e p u r i f i c a t i o n o f g l u t a r a l d e h y d e is e x p r e s s e d as t h e p u r i f i c a t i o n i n d e x , Pi

=

e x t i n c t i o n at e x t i n c t i o n at

235 280

nm nm"

A t 235 n m t h e i m p u r i t i e s a n d p o l y m e r s a r e m e a s u r e d w h i l e at 280 n m t h e m o n o m e r s a r e measured. 3 F o r the d i s t i l l a t i o n p r o c e s s we h a v e u s e d an a d i a b a t i c f r a c t i o n a t i o n c o l u m n to r e d u c e t h e h e a t e x c h a n g e . T h e i n t e r i o r o f t h e f r a c t i o n a t i o n c o l u m n is f i l l e d w i t h s m a l l g l a s s c y l i n d e r s , l e a d i n g to a l a r g e s u r f a c e i n c r e a s e , thus f a c i l i t a t ing the p u r i f i c a t i o n of the g l u t a r a l d e hyde. T h e v a p o u r s c o n d e n s e in a v e r t i c a l c o o l i n g u n i t a n d t h e d i s t i l l a t e is l e d to t w o f l a s k s . T h e d i s t i l l a t i o n is c a r r i e d out u n d e r v a c u u m at a p r e s s u r e o f 10 m m o f m e r c u r y . A n a m o u n t o f 650 m l 25% g l u t a r a l d e h y d e s o l u t i o n w i t h a Pi > 10 w a s d i s t i l l e d each time, u s i n g a flask h e a t e d

P. J. Anderson, J. Histochem. Cytochem. 15 (1967) 652. H. D. Fahimi, P. Drochmans, J. Microscopie 4 (1965) 725. E. A. Robertson, R. L. Schultz, J. Ultrastr. Res. 30 (1969)

QUANTITATIVE A C Q U I S I T I O N AND E V A L U A T I O N OF E L E C T R O N M I C R O G R A P H Y U S I N G A S T E M A.

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P r e p a r a t i o n and o b s e r v a t i o n of b i o l o g i c a l samples with e l e c t r o n microscopical m e t h o d s i n e v i t a b l y l e a d to d i s t o r t i o n s and o t h e r k i n d s of n o i s e , w h i c h o b s c u r e the r e p r e s e n t a t i o n of the true s t r u c t u r e . D i g i t a l a c q u i s i t i o n of e l e c t r o n micrographs u s i n g a STEM provides images in a f o r m a t r e a d y f o r d i g i t a l p r o c e s s i n g , w h i c h in t u r n p e r m i t s e x t r a c t i o n o f b i o logically useful structural information from n o i s y images.

INTRAMEMBRANEOUS PARTICLES ASSOCIATED WITH S U R F A C E IMMUNOGLOBULIN RECEPTORS IN T H E P L A S M A M E M B R A N E O F B L Y M P H O C Y T E S C.

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L a b o r a t o r y of H i s t o l o g y and Cell Biol o g y , U n i v e r s i t y of A m s t e r d a m , 1 e C o n e t . H u y g e n s s t r a a t 20, 1054 BW A m s t e r d a m , The N e t h e r l a n d s

C o n v i n c i n g e v i d e n c e is a c c u m u l a t i n g t h a t s u r f a c e i m m u n o g l o b u l i n (sIg) r e c e p tor m o l e c u l e s of B l y m p h o c y t e s p o s s e s s two " e x t r a " h y d r o p h o b i c a m i n o a c i d seq u e n c e s w h e n c o m p a r e d w i t h s e c r e t e d imm u n o g l o b u l i n s . I-3 These hydrophobic p e p t i d e s a r e b e l i e v e d to f o r m a t r a n s m e m b r a n e s t r u c t u r e t h a t p l a y s an i m p o r t a n t r o l e in t h e t r a n s f e r o f a s i g n a l to the c y t o p l a s m . In t h e p r e s e n t s t u d y w e h a v e t r i e d b y f r e e z e - f r a c t u r i n g to v i s u a l i z e i n t r a m e m b r a n e o u s p a r t i c l e s (IMPs) s p e c i f i c a l l y a s s o c i a t e d w i t h sIg r e c e p t o r m o l e c u l e s . s I g r e c e p t o r s .on m o u s e a n d r a b b i t s p l e e n B l y m p h o c y t e s w e r e r e d i s t r i b u t e d by a n t i b o d i e s i n t o p a t c h e s and g l u t a r a l d e h y d e f i x e d c e l l s f r o z e n in 35% g l y c e r o l w e r e