[Pharmacological availability of erythromycin granules for children's use]. / Farmatsevticheskaia dostupnost' detskoi lekarstvennoi formy éritromitsina v vide granul.

Pharmaceutical availability of erythromycin granules with polymeric coating of different composition+ was studied. With an account of the ++anatomo-physiological features of a child organism and the properties of the antibiotic, acetylphthalyl cellulose in combination with hydroxypropyl methylcellulose or methyl cellulose was used as a film forming agent. The coated granules were estimated by such parameters as the time of disintegration and the rate of dissolution in various media. The results of the study showed that coating of the erythromycin granules with the film composed of acetylphthalyl cellulose and hydroxypropyl methylcellulose in the ratio of 8 to 2 provided the required protection of the antibiotic in acid media and high pharmaceutical availability of the drug.

[Biopharmaceutical aspects of the medicinal forms of cephalexin]. / Biofarmatsevticheskie aspekty lekarstvennykh form tsefaleksina.

The rate of cephalexin release from various dosage forms such as tablets, capsules and suspensions manufactured by several firms was studied. In vivo studies showed that pharmacokinetic indices of the absorption depended on the rate of cephalexin release from the dosage forms. The proposed procedure for in vitro estimation of the cephalexin release rate reflects bioavailability of the antibiotic dosage forms and may be used in quality control of finished dosage forms.

[Pharmaceutical aspects of creating an effective drug form of carfecillin]. / Farmatsevticheskie aspekty sozdaniia éffektivnoi lekarstvennoi formy karfetsillina.

Physical and technological parameters of carfecillin powder and carfecillin with auxiliary substances in the form of the powder mixture and granulate were studied comparatively. Possible preparation of carfecillin capsules characterized by high levels of the antibiotic dissolution was shown.

[Effect of crystallinity on the rate of solution of oxytetracycline hydrochloride]. / Vliianie kristallichnosti na skorost' rastvoreniia oksitetratsiklina gidrokhlorida.

The crystal structure of 2 forms of oxytetracycline hydrochloride prepared with the method of crystallization from various solvents was studied. It was shown that these forms were 2 polymorphic modifications of the antibiotic with different crystal structures. The modification prepared with the method of crystallization from methanol was characterized by better dissolution in water. Its dissolution rate constant was 3 times as higher which makes this crystalline modification of oxytetracycline hydrochloride preferable for preparation of the antibiotic pharmaceutical forms with high bioavailability levels.

[Effect of the antibiotic granulation method on the quality of semisynthetic penicillin capsules (e.g., the sodium salt of dicloxacillin)]. / Vliianie sposoba granuliatsii antibiotikov na kachestvo kapsul polusinteticheskikh penitsillinov (na primere dikloksatsillina natrievoi soli).

A procedure for dry granulation of antibiotics consisting in dry compacting of a powder-like composition followed by its grinding to granules was developed. The advantages of dicloxacyllin capsules manufactured by dry granulation over the capsules manufactured by moist granulation are shown with respect to the content of the light absorbing admixtures during the capsule manufacture and storage. The conditions for estimation of the antibiotic dissolution from the capsule were developed with the use of a "Rotating Basket" apparatus. Comparative evaluation of disintegration and dissolution of the capsules prepared by dry or moist granulation showed practical equivalence of both types of the capsules with respect to these characteristics.

[Quality and stability of tetracycline tablets]. / Kachestvo i stabil'nost' tabletok tetratsiklina.

Tetracycline base tablets with dragee (sugar) and gastric soluble film coatings were investigated. Advantages of the tablets with the film coating in the main characteristics, such as bioavailability and levels of tetracycline-like admixtures were shown. The structure of the surface layer of the dragee coating was studied. It was found that the products contained in the coating and magnesium carbonate, in particular, lowered the tablet solubility.

[Doxycycline bioavailability in capsules]. / Biodostupnost' doksitsiklina v kapsulakh.

Soviet doxycycline capsules in a dose of 0.1 g were studied in vitro (for disintegration and solubility) and in vivo (pharmacokinetics on 25 patients). It was found that Soviet doxycycline capsules provided comparatively rapid absorption of doxycycline. The antibiotic availability may be characterized by the solubility test. The results of the study on bioavailability of Soviet doxycycline capsules were compared with the results of analogous studies published by American authors for doxycycline capsules manufactured by various firms of the USA.

[Comparative evaluation of methacycline hydrochloride capsules and tablets according to their dissolubility and rate of solution]. / Sravnitel'naia otsenka kapsul i tabletok metatsiklina gidrokhlorida po raspadeamosti i skorosti rastvoreniia.

Desintegration and dissolution of capsules and tablets of methacycline hydrochloride were studied. The study on solubility of methacycline hydrochliride capsules filled with methacycline granulate or powder according to the same formula showed that the rate of the antibiotic liberation from the capsules filled with the powder decreased during storage while that from the capsules filled with the granulate did not change. Investigation of the effect of the mass packing value in a drop on the antibiotic liberation from the capsules showed that an increase in the packing coefficient above 1.38 resulted in a marked decrease in the rate of methacycline liberation from the capsules filled with the granulate. No correlation between desintegration and dissolution of methacycline capsules and tablets was found.

[Bioavailability of ampicillin suspensions]. / Biodostupnost' suspenzii ampitsillina.

The rate of ampicillin transfer into solution from suspensions of 2 types, i.e. suspensions of anhydrous ampicillin and suspensions of ampicillin trihydrate was studied. Conditions for estimation of the rate of ampicillin dissolution from the suspensions were developed. The pharmacokinetics of the pharmaceutical forms was studied on dogs. Definite advantages of the anhydrous ampicillin suspension were shown as compared to the ampicillin trihydrate suspension.

[Effect of auxiliary substances on the bioavailability of tetracycline hydrochloride capsules (an in vitro study)]. / Vliianie vspomogatel'nykh veshchestv na biodostupnost' kapsul tetratsiklina gidrokhlorida (issledovanie in vitro).

The rate of tetracycline hydrochloride transfer into solution from capsules containing different auxiliary substances was studied. It was shown that the dispersity level of tetracycline hydrochloride powder had no significant effect on the capsule disintegration and the rate of the antibiotic transfer into solution. The effect of the auxiliary substance composition on the capsule disintegration and the rate of the antibiotic dissolution was shown. The rate of tetracycline liberation from the capsules containing tetracycline hydrochloride without additives or the antibiotic in combination with 23 per cent of lactose was 4 to 6 times higher than that from the capsules with magnesium carbonate or calcium phosphate as the auxiliary substances.

[Properties and stability of tetracycline hydrochloride tablets]. / Nekotorye svoistva i stabil'nost' tabletok tetratsiklina gidrokhlorida.

Three forms of tetracycline hydrochloride tablets were studied, i.e. the uncoated tablets, sugar-coated tablets and the tablets with gastric-soluble film coating. The film-coated tablets had advantages in the main quality characteristics, i.e. the contents of the tetracycline-like admixtures, the active substance and solubility rate. The possibility of the tablet stability investigation by the method of "accelerated aging" was shown.

[Rate of tetracycline dissolution from tablets and capsules and the biological availability of the antibiotic]. / Skorost' rastvorennia tetratsiklina iz tabletok i kapsul i biologicheskaia dostupnost; antibiotika

Relation between the rate of tetracycline dissolution from tablets and capsules and the biological acceptibility of the antibiotic in the host was studied. The antibiotic dissolution rate from the pharmaceutical forms was determined in a modernized apparatus "Rotary basket" in water, the speed of the basket rotation was 200 r.p.m. In addition the tetracycline blood levels in patients treated with the drug in the above pharmaceutical forms were estimated. It was found that the rate of the antibiotic dissolution characterized the antibiotic biological acceptibility. A test for the dissolution rate was developed. It may be used for estimation of production batches of tetracycline tablets.