The four com pounds 3-amino-5-acetamido-2- and -4-hydroxyphenylarsenoxide hydrochlorides and hydr- iodides dissolve in water only after keeping for a few secon d s; the formulation
N H2-CGH2(OH)(NHAc)-AsCl-OH, hydrolysed b y water to HC1,NH2-C6H2(OH)(NH Ac)-AsO, is suggested.
M. Cl a r k.
O r g a n ic c o m p o u n d s o f a rs e n ic. X I I I . c y c lo - P e n ta -n -p ro p y lp e n ta -a rs in e a n d th e th e r m a l d e c o m p o s it io n o f a rs e n o -d e riv a tiv e s . W . St e i n- k o p f and H . Du d e k (Ber., 1928, 61, [2?], 1906— 1911;
cf. this vol., 654).— Magnesium n-propylarsinate is reduced b y sodium liypophosphite and sulphuric acid to
cyc\opcnta-n-propylpenta-arsine,
[C3H7A s]5, b. p.177— 179°/1 mm. (slight decom p.), which contains about 5 % of propylcacodyl. In freezing nitro
benzene the product has the expected mol. wt., thus affording indirect evidence in favour of the cyclic constitution assigned to the pontamethylpenta-arsine
(loc. cit.).
The com pound is decom posed when distilled under 13 mm. pressure into arsenic andpropylcacodyl,
b. p. 165—167°/1 3 mm., converted by exhaustive m ethylation intodimethyldi-Vi-propylarson- ium tri-iodide-,
this change explains the unavoidable presence of propylcacodyl in distilledcyclop
lenta- w-propylpenta-arsine. Similarly, ci/cfopentamethyl- penta-arsine is decomposed at 270°/atm . into arsenic and cacodyl. Arsenobenzene at 255° analogously yields arsenic and phenylcacodyl. H . Wr e n.M e r c u r a tio n o f a r o m a t ic a m in e s a n d the p r o b le m o f su b s titu tio n . I. A . F . Al b e r t and W . Sc h n e i d e r (Annalen, 1928, 465, 257— 272).— On the basis of W ieland’s addition theory o f substitution, Kharascli and Jacobsohn (A., 1922, i, 189) postulated the production o f com plex salts in the mercuration o f aromatic amines. Such salts have now been isolated.
The action o f mercuric acetate on an aromatic amine m ay be represented by the typical scheme : N H 2Ph (I) [N H2Ph-H g-O Ac]O Ac — y (Ila )
N H Ph-H g-OAc + (IB ) NHPh-H g-OH — y (III) N HyCjjHpH g-OAc. W ith aniline, a methyl-alcoholic solution of the amine is treated with a methyl- alcoholic suspension of mercuric a ceta te; after addition o f a little acetic acid the mixture becomes clear and on cooling deposits aniline acetate 'N-mercuri- acetate (I), m. p. 87°. Similarly are obtained : p-toluidine, m. p. 155°, o -toluidine, m. p. 76°, m-amino- acetophenone, m. p. 104°, p -anisidine, m. p. 125°, and bis-o-toluidine, m. p. 96°, acetate N-mercuriacetates.
These com pounds are very unstable, changing slowly on keeping, or at once on melting, or heating in aqueous or alcoholic solution, into the m ono- and di-nuclear-substituted products. (W hen aniline acetate W-mercuriacetate was kept in a vacuum, no change of com position occurred, but the m. p. changed.) In the cold, ammonium sulphide, sodium hydroxide, or sodium iodide solutions all give with I the corre
sponding mercuric com pound. Sodium iodide m ay be em ployed to distinguish between the different stages of the reaction, since with I sodium acetate is form ed in solution, but with II, sodium hydroxide also. A t stage I I I alkalinity is developed only in so far as mercury is being rem oved from the nucleus.
The stage I I com pound is obtained, in the case of aniline, b y shaking I with eth er; aniline N -mercuri- acetate is obtained impure, m. p. about 154°. Stage I I is the first result of the action of mercuric acetate on ethyl p-aminobenzoate, which gives a product, m. p.
117°, estimated, from the analytical results, to contain 80% of Ila , 12% of 116, and 8% of mercuric acetate.
Stage I I com pounds have a great surface-activity, e.g., in adsorbing impurities ; the above product when pre
pared in ether yields a solid mass, which contains adsorbed ether, and becomes gelatinous in water.
p-Aminoacetoq>henone and m-nitroaniline also give stage I I products. These are more stable than I (e.g., in water), but are converted b j’ acetic acid into nuclear-substitutcd compounds.
p-Ethylam inophenylm ercuric acetate and p-di- metliylaminophenylmercuric acetate have been pre
pared, without intermediate products being isolated.
It is suggested that if the stage I — y I I cannot take place at the ordinary temperature, mercuration will not occur (cf. mercuric chloride).
Attention is directed to the danger that, since impurities m ay be introduced b y adsorption, pharm
acological mercury com pounds m ay be impure.
E . W . Wi g n a l l. C o n s t i t u t i o n o f o r g a n o - m a g n e s i u m c o m p o u n d s . Q. M i n g o i a (Gazzetta, 1928, 5 8 , 532—
541).— Contrary to Kierzek’s statement (A., 1927, 1176), the magnesium bromohydrosulphide prepared b y the author (A., 1926, 388) was isolated and analysed. B y decomposing magnesium methyl iodide with water and then extracting with ether, Kierzek found that magnesium iodide is rem oved, but this author’s conclusion that the organo-magnesium com pound and water react with formation of magnesium hydroxide and iodide in equimolecular proportions is fallacious, since b y prolonged extraction with ether he was able to extract only 72-63% o f the iodide, the residual com pound still containing 25-25% o f iodine, in spite o f the appreciable solubility of magnesium
iodide in anhydrous ether. The change o f colour from white to brown during the treatment with ether is explainable more readily b y assuming gradual decom position o f the magnesium iodohydroxide into magnesium iodide and hydroxide. Further, treat
ment Math pyridine o f the organo-magnesium solution decomposed b y water fails to yield [Mg(C5H5N )6]I2 or [Mg(C5H6N )4(Et20 )2]I2 (cf. Spacu, A ., 1922, i, 859), this behaviour being in agreement "with the predominant basic properties o f magnesium iodohydroxide. On the other hand, if the decom position is effected b y means o f hydrogen sulphide, treatment with pyridine yields the additive com pound o f pyridine and magnesium brom ohydrosulphide, in accord with the distinctly saline properties o f the latter com pound. The asymmetric formula for the organo-magnesium com pounds is upheld in preference to the doubled symmetrical formula. T. H . Po p e.
M e t h o d o f p r e p a r in g se le n o p h e n . H. V . A-Br i s c o e, J. B . Pe e l, and P. L. Ro b in s o n (J.C.S., 1928, 2628— 2629).— Selenium, in portions o f 5 g., is heated in an inclined Pyrex tube, closed at the lower end, and provided with an axial inlet tube delivering acetylene some inches above the selenium and well below a side tube leading to a condenser. The middle o f the tube is heated to redness, and the selenium is slowly vaporised b y heating it from the surface downwards. Flashing of the acetylene, accom panied b y deposition o f carbon, takes place and a liquid condensate is formed thereafter at the rate of 3— 4 c.c. in 4 lirs. Fractionation o f the crude oil yields a high percentage o f selenophen (cf. this vol.,
1021). M. Cl a r k.
A tt e m p te d p r e p a r a tio n o f o p tic a lly a ctiv e d e r iv a tiv e s o f q u a d riv a le n t tin . F. B. K i p p i n g (J.C.S., 1928, 2365— 2372; cf. Pope and Peachey, Proc. C.S., 1900, 16, 42, 116).— The relative ease of rem oval b y iodine o f aromatic groups attached to a tin atom in m ixed arylstannanes decreases in the following order : o-tolyl, p -tolyl, phenyl, benzyl. The tin aryls are also decom posed by boiling with concentrated hydrochloric acid, which frequently removes two aryl groups. The order in which this rem oval occurs is the same as that with iodine, except that whereas iodine rem oves one o f the benzyl groups from tribenzyl- ethylstannane, hydrochloric acid removes the ethyl group. Three com pounds containing an asymmetric tin atom are described : phenyl-p-tolylbenzylstannic hydroxide, phenylbenzyl-w-butylstannic hydroxide, and benzylethyl-w-butylstannic iodide. Their salts with d-eamphorsulphonic, d-a-bromo-n-camphorsul- phonic, and tartaric acids have been prepared, but in no case could crystalline salts or any evidence of optical activity o f the tin atom be obtained. The following are described:
phenyltribenzylstannane,
b. p. 290°/5 m m .;
tribenzylstannic iodide,
m. p. 102— 103°;triphenylbenzylstannane,
m. p. 90°, b. p. 250°/3 m m .;phenylbenzylstannic chloride,
m. p. 83— 84°; p-tolyltri- benzylstannane
;iriphenyl-o-tolylstannane,
m. p. 165°;tri--p-tolyl-o-tolylstannane,
m. p. 168°;tri-m-tolylstannic chloride,
m. p. 108— 109°;tri-m-tolyl-p-tolylstannane,
m . p. 103°;
phcnyldi-p-tolylbenzylstannane,
b. p.265— 270°/2— 3 m m .;
phenyl-p-tolylbenzylstannic hydroxide,
m . p. 136— 137° (oilyiodide,
d-camphor-sidpho7iate,d-a-bromo-r.-camphorsulphonate;
d-tartrate
) ;triphenyl-n-butylstannane,
m . p. 61— 6 2 °, b. p. 2 2 2 ° / 3 m m .;plienyl-n-butylstannic chloride,
m . p. 5 0 °;diphenylbenzyl-n-butylstannanc,
b. p. 2 1 5 ° /2 — 3 m m .;phenylbenzyl-n-butylstannic hydroxide,
m . p . 1 3 5— 137°(fluoride,
m. p. 2 1 8 °, oilychloride, bromide, iodide,
d
-camphorsulphonate, d-v.-bromo-r:-camphorsulphonate
and
d-camphor ate \
d-tartrate)-, dibenzylethyl-\\-butyl- stannane,
b. p. 195— 2 0 0 ° /3 — 5 m m . ;benzylethyl-
n -butylstannic iodide.
M. C l a r k . A p p a r a tu s f o r c h r o m ic a n h y d rid e o x id a tio n s.W . F. S h o r t (J.C .S , 1928, 2630).— A slight m od i
fication o f W alker’s apparatus
(ibid.,
1892, 6 1 , 717) for the preparation o f alkyl iodides is described, the adaptor and side-tube being sealed together as in a Soxhlet apparatus. A . I. V o g e l .P a r t ia l d e c o m p o s itio n o f a lk a li c h lo r id e s in th e in c in e r a tio n o f o r g a n ic m a tte r (p a rticu la r ly n it r o g e n o u s o r g a n ic m a tte r ). P. Fl e u r y and P.
Am b e r t(Bull. Soc. Chim. biol., 1928,1 0 , 869— 878).—
Incineration o f mixtures o f sodium chloride and various organic substances (especially those o f the purine group) results in the loss o f chlorine (46— 8 0% ) and the formation o f sodium hydroxide and carbonate.
The presence o f salts o f nitrous, hydrocyanic, cyanic, or oxalic acids could n ot be detected.
G . A . C . Go u g h.
M ic r o -d e te r m in a t io n o f s u lp h u r in an o r g a n ic c o m p o u n d . S. Ha n a i (Bull. Inst. Phys. Chem.
Res. T ok yo, 1928, 7, 915— 919).— The substance is weighed into a platinum boat which is introduced into a Pregl m icro-com bustion tube containing freshly reduced, pure nickel (from the oxalate). After displacement o f air b y hydrogen the substance is gently heated to 2 0 0° and allowed to volatilise on to the nickel catalyst*"which retains all the sulphur as sulphide. The contents of the tube are dissolved in hydrochloric acid in an atmosphere o f hydrogen and the hydrogen sulphide is passed into an ammoniacal solution of cadmium ch loride; the cadmium sulphide is oxidised b y iodine (liberated from permanganate and potassium iodide), and the excess of iodine is titrated with thiosulphate. J. W . Ba k e r.
J a ffe ’ s p ic r i c a cid re a ct io n . W . We i s e and C . T r o p p (Z. physiol. Chem., 1 9 2 8,1 7 8,1 25 — 138).— The picric acid reaction (red coloration in alkaline solution) first given for creatinine b y Jaffe (A., 1886, 1056) is a particular case of a general reaction o f com pounds with active methylene or methine groups. I t is distinct from Braun’s reaction (1865) for dextrose and other reducing substances, in which the partial reduction of picric acid to red picramic acid takes place. Generally this reaction takes place only on warming. Jaffe’s reaction, according to Reissert (A., 1904, i, 389), is p robably a condensation process. In tests o f a large number o f com pounds the following order was found for the power o f groups in activating methylene or methine groups so that the com pound gave Jaffe’s re a ctio n : N 0 2, d ia zo-> :C O > *C N , CH2:C H ->-C O -N H 2, -C 02Et.
R . K . Ca l l o w. C re a tin e -p h o s p h o ric a cid a n d m e th o d s of d e te rm in a tio n . D . F e r d m a n n [w ith O . F e i n -
s c h m i d t] (Z. p h y s io l. C h em ., 1928,178, 52— 61).—T h e
1268 B R IT IS H CH E M ICAL A B ST R A C T S . A .
creatine-phosphoric acid (phosphagen, cf. Eggleton and Eggleton, A ., 1927, 271, 274; Fiske and Sub- barow, ibid., 990) o f muscle is rapidly destroyed at the ordinary temperature b y grinding the muscle, but this fermentative change can be inhibited b y grinding avith quartz sand and sodium borate, thus enabling a quantitative determination o f the creatine-phosphoric acid to be made, using a modification o f Eggleton’s m ethod. The form ation o f lactacidogen, as shown b y the decrease in inorganic phosphate, still takes place when the creatine-phosphoric acid has been destroyed,
a n d t h e p r e s e n c e o f t h e l a t t e r i s , t h e r e f o r e , n o t e s s e n t i a l f o r t h i s p r o c e s s . I t . K . Ca l l o w.
D e te r m in a tio n o f p y r u v ic a cid . B. H . R .
Kr i s h n a and M. Sr e e n i v a s a y a.—See this vol., 1292.
D e te r m in a tio n o f c a rn o s in e . W . M. Cl i f f o r d
and V . H . Mo t t r a m.— See this vol., 1292.
D e te r m in a tio n o f tr y p to p h a n a n d ty r o s in e in p r o te in s . J. Ti l l m a n s, P. Hi r s c h, and F . S T o r r E L .
— See t h i s v o l . , 1278.
Biochemistry.
G a s a n d e le ctr o ly te e q u ilib r ia in b lo o d . X II.
V a lu e o f j)Il' in th e H e n d e r s o n -H a s s e lb a lc h e q u a tio n f o r b lo o d -s e r u m . A . B. Ha s t i n g s, J.
Se n d r o y, jun., and D. D. Va n Sl y k e (J. Biol. Chem., 1928, 7 9 ,1S3— 192).— Taking the solubility coefficient of carbon dioxide in blood-serum to be 0-510, as recently determined b y Van Slyke and others (this vol., 1150), the value o f p K ' in the H enderson- Hasselbalch equation for blood-serum at 38° is 6-10; taking B ohr’s value of 0-541 as the solubility coefficient, p K ' becomes 6-13.
C. R . Ha r i n g t o n.
G a s a n d e le ctr o ly te e q u ilib r ia in b lo o d . X I I I . D is t r ib u t io n o f c h lo r id e a n d h y d r o g e n c a r b o n ate in b lo o d o f n o r m a l a n d p a th o lo g ic a l h u m a n s u b je c ts . A . B. Ha s t i n g s, J. Se n d r o y,
ju n ., J. F. McIn t o s h, and D . D. Va n Sl y k e
(J. Biol. Chem., 1928, 79, 193— 209).— In normal human blood the ratios [Cl]ceiis : [Cl]a and [BHCOgJcua : [B H C 0 3]serum are higher than those pre
viously determined (A., 1923, i, 1249) for horse b lood ; this is ascribed to the higher base-binding capacity of the proteins o f the latter. In a variety of pathological conditions, the distribution of the electrolytes in human blood was found to obey the same laws as in the normal. C. R . Ha r i n g t o n.
D e te r m in a tio n o f p n [o f b lo o d ] b y h y d r o g e n e le c tr o d e a n d b y c o lo r im e t r ic m e th o d s . C. G.
Jo h n s t o n (J . Biol. Chem., 1928, 7 9 , 297— 307).—
Comparison of the p a of blood as determined b y the hydrogen electrode and by the colorimetric methods o f Cullen (A., 1922, ii, 672), Hastings and Sendroy (A., 1924, ii, 869), and of Dale and Evans (A., 1921, i, 142) indicates that the results of the colorimetric determinations differ from those o f the electrometric m ethod b y inconstant amounts, the range of variation being greater than that observed b y previous workers ; particularly inconstant values were obtained in clog’s blood after hœmorrhage. I t is therefore suggested that no colorimetric m ethod is at present trustw orthy for the determination o f the p u o f blood with accuracy. C. R . Ha r i n g t o n.
E le c t r o m e t r ic titra tio n o f h æ m in a n d h æ m a tin . J. B. Co n a n t, G. A . Al l é s, and C. O. To n g b e r g
(J. Biol. Chem., 1928, 7 9 , 89— 93).— The conclusions o f Hill and H olden and o f Haurowitz (A., 1927, 6 8 6, 689) that thé reduction of hæmatin involves one
equivalent are confirmed by the electrometric titration of hæmin with titanous chloride in presence of tartrate. C. R . Ha r i n g t o n.
B l o o d - c o r p u s c l e s o f c o w s a n d f o e t u s e s i n h y p e r t o n i c s a l t s o l u t i o n s . D . v o n D e s e ô (Biochem. Z . , 192S, 1 9 9 , 41— 47).— Fœ tal blood-corpuscles shrink more in hypertonic salt solutions, contain more free water, have a greater volume, and contain more colloidal material than those of the mother.
J. H . Bi r k i n s i i a w.
B lo o d - c e ll m e ta b o lis m . II. E ffe c t o f m e th y l- e n e -b lu e and o th e r d y e s o n g ly c o ly s is a n d la c tic a c id fo r m a t io n o f e r y th ro c y te s . E. S. G. Ba r r o n
and G. A. Ha r r o p, jun. (J. Biol. Chem., 1928, 7 9 , 65—
87).— The glycolysis brought about b y mammalian erythrocytes is essentially anaerobic in character, the proportion of lactic acid produced to dextrose destroyed being high ; with avian erythrocytes a larger proportion o f the dextrose is oxidised. In both cases the addition of small amounts o f methylene- blue or of other dyes with similar oxidation-reduction potentials favours the oxidative part of the process.
The effect of the dye is exercised over a considerable range of concentration and is probably catalytic in character. The rate of glycolysis is increased by rise of temperature up to 37°. The catalytic effect of methylene-blue is not affected b y the presence of cyanides, but is increased b y addition o f phosphates and requires the presence o f molecular oxygen, whence it is probable that the dye catalyses the oxidation of hexosephosphate. Damage or destruc
tion of the surface of the erythrocytes inhibits partly or entirely their glycolytic activity.
C. R . Ha r i n g t o n.
B lo o d g ly c o ly s is . I. G e n e ra l c o n s id e r a tio n of g ly c o ly s is in re la tio n to th e b lo o d -c e lls , a n d th e p r o d u c t io n o f la c t ic a c id a n d c a r b o n d io x id e . I. Ka t a y a m a (J. Lab. Clin. Med., 1926, 1 2 , 239—
254).— The sugar content of shed blood decreases on keeping, m ost rapidly at 38° and least rapidly at 0° ; that of plasma, serum, or liæmolysed blood is unaltered. Saturation of whole blood with carbon m onoxide does not inhibit glycolysis.
Glycolysis takes place when washed blood-cells are added to Ringer or physiological saline solution containing dextrose, lævulose, or galactose (order of decreasing effect). The rate of glycolysis is the
same for diabetic and non-diabetic blood. Insulin has no effect on the rate. Lactic and evidently other acids, but not carbon dioxide, are produced.
Ch e m i c a l Ab s t r a c t s.
C a r b o h y d r a te d e g ra d a tio n a n d p h o s p h o r ic a cid in b lo o d . W . A. En g e l h a r d t and A . E . Br a u n- s t e i n (Klin. W och., 192S, 7, 215).— Of the two processes contributing to the phosphoric acid balance in blood observed in vitro, the separation of inorganic phosphate is independent o f glycolysis, whilst the union of phosphoric acid as an organic stabilisation product is directly connected with the disappearance of sugar. Conditions diminishing or inhibiting glycolysis cause a corresponding diminution of phosphoric acid stabilisation. Addition of dextrose to erythrocyte suspensions reduces the speed of liberation of phosphoric acid, but such addition is without influence in systems where glycolysis cannot occur. Addition o f arsenate prevents phosphoric acid stabilisation when disappearance o f sugar is proceeding. A . A . El d r i d g e.
C a ta ly tic d e c o m p o s itio n o f h y d r o g e n p e r o x id e b y b lo o d . I. C h e m ic a l d y n a m ic s o f b lo o d - ca ta la se . II. E ffe c t o f te m p e r a tu r e o n b l o o d - ca ta la se . III . C a ta ly tic a ctiv ity o f th e r e d ce lls.
IV . S o -c a lle d h e a t-a ctiv a tio n a n d in flu e n ce of s o m e o r g a n ic s u b s ta n c e s on th e r e d b lo o d -c e ll c a ta ly sis. K . No s a k a (J. Bioehem. Japan, 1928, 8, 275— 299, 301— 309, 311— 330, 331— 340).— I.
The catalytic decomposition of hydrogen peroxide (0-009— 0-036iV) b y blood solutions is not unimolecu- lar, but corresponds with Yam azaki’s formulation,
—d cjd t= k E G ; —d E jd t= k 'E C , where E is the con
centration o f catalase and C that of hydrogen per
oxide. Variation o f values of k with variable quanti
ties of enzyme is corrected b y k1/k2= ( E 1IE2)m, where m is constant (1-07) for different temperatures.
Blood-serum has no catalytic effect, but is protective.
The optimal p n for blood-catalase is 7 ; the p a has practically no influence on the destruction of catalase b y the hydrogen peroxide.
II. The temperature curve for blood-catalase shows a wide optimum range at about 4 0°; between 0° and 20° the coefficient is 1-49 per 10°. The temperature curve for the destruction of the catalase b y hydrogen peroxide is very steep and has no op tim u m ; between 0° and 35° the coefficient is 2-2 2 per 1 0°. Inactivation b y heat is not a uni- molecular reaction. Blood-catalase is. inactivated b y heating for 30 min. at 65° or 15 min. at 70°.
I I I . A suspension of red blood-cells in physio
logical sodium chloride solution decomposes hydrogen peroxide unimolecularly provided there is no haemolysis; serum and plasma have a stimulating effect. The reaction is regarded as a special case of hydrogen peroxide catalysis without the intervention o f catalase.
. IV . The catalytic effect of the red-cell suspension on hydrogen peroxide is considerably increased, owing to haemolysis, b y heating at 45°. A ctivation b y various protoplasm ic poisons is similarly occasioned.
Ch e m i c a l Ab s t r a c t s.
E ffe c t o f c a r b o n m o n o x id e o n th e m e t a b o lis m o f le u c o cy te s . A . Fu j i t a (Bioehem. Z., 1928, 1 9 7 ,
189— 192).— W hen the ratio C 0 / 0 2= 1 8 the respir
ation of leucocytes and o f white bone-marrow cells as well as that of blood-platelets is checked, the effect being very strong in the case o f the last two.
Illumination with a metal-filament lamp diminished the effect, especially in the case of the marrow cells and
platelets. W . McCa r t n e y.
P e r o x id a s e p r o p e r t ie s o f le u c o cy te s . K .
Ni c o l a j e v (Zhur. exp. biol. Med., 1928, 8, 33— 41).—
Leucocytic extracts have peroxidase properties which disappear on boiling. The intensity of the oxidation process has no relation to the iron content.
Ch e m i c a l Ab s t r a c t s.
D e c o m p o s it io n o f u r ic a cid in b lo o d . M.
Go m o l i n s k a (Bioehem. J., 1928, 2 2 , 1307— 1311).—
Uric acid is quantitatively oxidised b y blood to allantoin, urea, and ammonia within 48 hrs. at 37°.
Strom ata and blood-plasma arc inactive in this respect. Haemoglobin is m ost probably the uricolytic agent present in blood. The reaction of uricolysis is inhibited by propyl and butyl alcohols but not by
cyanides. S. S. Zi l v a.
P r e c ip ita tio n o f b lo o d -c a lc iu m b y le a d . F.
Bi s c h o f f and L. C. Ma x w e l l (J. Biol. Chem., 1928, 7 9 , 5— 17).— A ddition of lead acetate to blood-serum at jhi 6'9— 8-3 causes precipitation of an equivalent amount of calcium and of phosphoric acid sufficient to form the phosphates of both the lead and the calcium. The reaction is independent o f the con
centration o f calcium, carbonate, and phosphate, and is a specific effect of lead. C. It. I Ia r i n g t o n.
E le c tr ic a l tr a n s fe r e n ce o f c a lc iu m in b lo o d - s e r u m p r o te in s o lu tio n s . D . M. Gr e e n b e r g (J.
Biol. Chem., 1928, 7 9 , 177— 182).-—Blood-serum was freed from electrolytes b y electrodialysis, and the resulting solution was treated with varying amounts o f calcium hydroxide alone or together with sodium hydroxide. Measurement of the electrical transport numbers o f such solutions affords evidence of the form ation of com plex calcium -protein ions, although this com plex ion formation is not so marked as with easeinogen (this vol., 241). C. R . Ha r i n g t o n.
C a lc iu m a n d in o r g a n ic p h o s p h o r u s in th e b lo o d o f r a b b it s . III . P e r io d ic a n d p r o g r e s s iv e v a ria tio n s in n o r m a l r a b b its . W . H . Br o w n
and M. Ho w a r d (J. E xp. Med., 1928, 4 7 , 637—
662).— Periodic variations o f calcium and the calcium / inorganic phosphorus ratio, and progressive vari
ations o f inorganic phosphorus and the same ratio, were observed. Ch e m i c a l Ab s t r a c t s.
D e te r m in a tio n o f c h lo r id e in b lo o d a n d s e ru m . D . W . Wi l s o n and E. G. Ba l l (J. Biol. Chem., 1928, 7 9 , 221— 227).— The m ethod o f Van Slyke (A., 1924, ii, 271) for the determination of chloride yields better results if the material be treated first with silver nitrate in aqueous solution and then with concentrated nitric acid. C. R . Ha r i n g t o n.
I r o n c o n te n t o f b lo o d -s e r u m . G. Ba r k a n (Z.
physiol. Chem., 1928, 1 7 7 , 205— 207).— A com ment on the work of Abderhalden and Moller (this vol., 913). J. H . Bi r k i n s h a w.
1270 B R IT IS H C H EM ICAL A B S T R A C T S . A .
[Iro n c o n te n t o f b lo o d -s e r u m .] E. Ab d e r- h a l d e n (Z. physiol. Chem., 1928, 177, 207— 210).—
A reply to Barkan (cf. preceding abstract).
J. H . Bi r k i n s h a w.
D e te r m in a tio n o f s u lp h u r in b lo o d a n d o r g a n ic p r o d u c t s . A . Le s u r e and A . Du n e z (Bull. Soc.
Chim. biol., 1928, 10, 879— 890).— A fter rem oval of the protein with acetic acid, the residue is oxidised with boiling, fuming nitric acid and the product decolorised with hydrogen peroxide. A 4 % solution of benzidine in 4 % hydrochloric acid is then added and the benzidine sulphate washed with pure acetone.
The sulphate is finally determined b y titration with sodium hydroxide solution. G. A . C. Go u g h.
I r r a d ia t e d p r o te in s . IV . E ffe c t o f s h o r t
w a v e ra d ia tio n o n th e u lt r a -v io le t a b s o r p tio n o f s e r u m a n d o f s e r u m -p r o te in . M. Sr i e g e l- Ad o l e
(Biochem. Z., 1928, 197, 197— 209).— The absorptive power of irradiated serum-albumin is independent of the presence of oxygen. Serum-albumin kept in an atmosphere of nitrogen exhibits quantitatively and qualitatively the same changes, and serum- albumin free from electrolytes, under the same conditions, also remains insoluble after treatment with alkali (cf. A ., 1927, 893; this vol., 190, 659).
Serum diluted with physiological salt solution and also pseudoglobulin irradiated in presence of alkali show an increase in absorbing power after irradiation.
Euglobulin, under the same conditions, exhibits no such change. As regards the extent of change in absorbing power undergone, the substances form the descending series : serum-albumin, serum, pseudo
globulin, euglobulin. The permeability of irradiated and unirradiated solutions of these substances by light of short wave-length provides confirmation of the results determined spectrographically.
W . McCa r t n e y.
P r e s e n c e o f p o ly p e p tid e s in b lo o d -p la s m a a n d
P r e s e n c e o f p o ly p e p tid e s in b lo o d -p la s m a a n d