scholarly journals PENENTUAN PROFIL ELUSI IODIUM-125 SEBAGAI PERUNUT UNTUK TUJUAN RADIOIMMUNIASSAY (RIA)

2016 ◽  
Vol 17 (2) ◽  
pp. 59
Author(s):  
Maiyesni Maiyesni ◽  
Mujinah Mujinah ◽  
Dede Kurniasih ◽  
Witarti Witarti ◽  
Triyatno Triyatno ◽  
...  
Keyword(s):  
Radiochemical Purity ◽  
Elution Profile ◽  
Alkaline Ph ◽  
Dose Calibrator ◽  
Purity Level ◽  
Before And After ◽  
Preliminary Study ◽  
Iodine 125

Manfaat iodium-125 (125-I) sudah banyak diketahui. 125-I  dapat digunakan antara lain sebagai perunut dalam teknik Radioimmunoassay (RIA) untuk deteksi dini berbagai penyakit kanker, menentukan kesuburan hewan ternak serta cemaran mikotoksin di dalam pangan secara invitro.  125-I  yang dibutuhkan dalam teknik ini disamping harus mempunyai kemurnian radiokimia > 95%,  konsentrasi radioaktifitas   juga tinggi, sehingga volume  125-I  haruslah sekecil mungkin. Dengan demikian perlu dipelajari profil elusi 125-I dari kolom reduktor Jones saat proses peningkatan kemurnian  radiokimia. Penelitian ini bertujuan untuk menentukan volume optimal  eluat dengan efisiensi dan kemurnian radiokimia yang dapat diterima. Pada penelitian ini kondisi kolom yang dipilih adalah kolom dengan pH basa. Kolom reduktor Jones yang mengandung  125-I dielusi dengan larutan  NaOH 0,01N secara  fraksinasi volume 1 ml. Radioaktifitas  masing-masing fraksi diukur menggunakan  dose calibrator. Penentuan kemurnian radiokimia dilakukan pada fraksi yang memiliki radioaktifitas  tertinggi dan fraksi gabungan  dengan  metode kromatografi kertas. Radioaktifitas  tertinggi ditunjukkan pada  fraksi kedua  yaitu  16,59  mCi dengan efisiensi 33,95% dan fraksi gabungan yaitu 50,19 mCi dengan efisiensi 92,26%. Kemurnian radiokimia 125-I bulk, fraksi kedua dan fraksi gabungan berturut-turut adalah 41,50, 97,5  dan  98,50%.  Volume optimal eluat adalah 7 ml serta  pH 125-I sebelum dan sesudah fraksinasi adalah 10 -11.  Determination of  Elution Profile the Iodine-125 as a tracer for Radioimmunoassay (RIA). The benefits of the Iodine-125 (125I ) isotope was well known. 125I are used as radiotracer in Radioimmunoassay (RIA) technique for early detection of cancer, determine of hormone content which related with fertility of livestock and also for contamination detection of mycotoxins on food by in vitro.  125I which is needed in this technique not only must have high radiochemical purity above 95% but also high radioactivity concentration, so that  125I volume which is use must as little as possible. Therefore, 125I elution profile for increasing radiochemical purity using a reductor Jones column should be studied. Aim of this study is to determine the optimum volume of eluate which have efficiency and radiochemical purity that can be accepted. The preliminary study was conducted to determine the optimal conditions of reductor Jones  column. Reductor Jones column is conditioned on neutral and alkaline pH. At this elution study, the columns conditions selected is alkaline pH. Reductor Jones column which containing 125I eluted with NaOH 0,01 N solution by fractionated in 1mL. The radioactivity of each fraction is measured with dose calibrator.  Determination of the radiochemical purity of carried out on the fraction which have the highest radioactivity and the combined fractions using paper chromatography. Highest radioactivity is shown in the second fraction at 16,59 mCi with efficiency 33,95%  and combined fractions at 50,19 mCi with efficiency 92,26%. The radiochemical purity of 125-I bulk, second fraction and combined fractions are 41,50%, 97,5 % dan  98,50%, respectively.  Optimum fraction is 7 mL and pH of 125-I before and after fractination are 10-11. By studying the elution profile can be known that the optimal volume is the smallest total volume of eluent with efficiency and radiochemical purity level that can be accepted. 

DETERMINATION OF BLOOD CORTICOIDS USING THE IN VITRO RESIN UPTAKE OF 3H-PREDNISOLONE

1968 ◽  
Vol 57 (1) ◽  
pp. 23-32 ◽  
Author(s):  
Hironori Nakajima ◽  
Mitsunori Murala ◽  
Masumitsu Nakata ◽  
Takeshi Naruse ◽  
Seiji Kubo
Keyword(s):  
Thyroid Function Test ◽  
Normal Subjects ◽  
Adrenal Function ◽  
Function Test ◽  
Before And After ◽  
Adrenal Response ◽  
Suppression Test

ABSTRACT The in vitro resin uptake of 3H-prednisolone was used for the determination of blood cortisol after addition of radioactive prednisolone followed by Amberlite CG 400 Type 1 to the test serum, and incubation of the mixture. The radioactivity of the supernatant was compared before and after the addition of the resin. The principle of this method is similar to that of the 131I-triiodothyronine resin uptake for the thyroid function test. The tests for the specificity, reproducibility and sensitivity gave satisfactory results. The mean basal value ± SD of the 3H-prednisolone resin uptake was 35.3 ± 9.2% in normal subjects, and 27.1 ± 4.8% in pregnant women. This method was valid in various adrenal function tests, i. e. the adrenal circadian rhythm, corticotrophin (ACTH) test, dexamethasone suppression test and the adrenal response to lysine-8-vasopressin. It proved to be a sensitive indicator of the adrenal function. These results suggest that this method should be useful for a routine adrenal function test.

scholarly journals Preliminary Study of a 1,5-Benzodiazepine-Derivative Labelled with Indium-111 for CCK-2 Receptor Targeting

Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 918
Author(s):  
Marco Verona ◽  
Sara Rubagotti ◽  
Stefania Croci ◽  
Sophia Sarpaki ◽  
Francesca Borgna ◽  
...  
Keyword(s):  
Radiochemical Purity ◽  
Single Photon ◽  
Photon Emission ◽  
Tumor Cell Line ◽  
Normal Tissues ◽  
Molar Activity ◽  
Suitable Target ◽  
Indium 111 ◽  
Preliminary Study

The cholecystokinin-2 receptor (CCK-2R) is overexpressed in several human cancers but displays limited expression in normal tissues. For this reason, it is a suitable target for developing specific radiotracers. In this study, a nastorazepide-based ligand functionalized with a 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) chelator (IP-001) was synthesized and labelled with indium-111. The radiolabeling process yielded >95% with a molar activity of 10 MBq/nmol and a radiochemical purity of >98%. Stability studies have shown a remarkable resistance to degradation (>93%) within 120 h of incubation in human blood. The in vitro uptake of [111In]In-IP-001 was assessed for up to 24 h on a high CCK-2R-expressing tumor cell line (A549) showing maximal accumulation after 4 h of incubation. Biodistribution and single photon emission tomography (SPECT)/CT imaging were evaluated on BALB/c nude mice bearing A549 xenograft tumors. Implanted tumors could be clearly visualized after only 4 h post injection (2.36 ± 0.26% ID/cc), although a high amount of radiotracer was also found in the liver, kidneys, and spleen (8.25 ± 2.21%, 6.99 ± 0.97%, and 3.88 ± 0.36% ID/cc, respectively). Clearance was slow by both hepatobiliary and renal excretion. Tumor retention persisted for up to 24 h, with the tumor to organs ratio increasing over-time and ending with a tumor uptake (1.52 ± 0.71% ID/cc) comparable to liver and kidneys.

scholarly journals DETERMINATION OF l-HISTIDINE IN NANOGRAM AMOUNTS AND THE QUESTION OF ITS OCCURRENCE IN MAST CELLS

1972 ◽  
Vol 20 (11) ◽  
pp. 917-922 ◽  
Author(s):  
DAVID I. WILKINSON ◽  
DAVID GLICK
Keyword(s):  
Mast Cells ◽  
Rate Limiting Step ◽  
Limiting Step ◽  
Peritoneal Mast Cells ◽  
Before And After ◽  
Chromatographic Detection ◽  
Rat Peritoneal Mast Cells ◽  
Rate Limiting

In an attempt to clarify the question of whether histidine is stored in the mast cell for coversion to histamine or whether the rate of conversion is rapid enough to prevent accumulation of histidine so that the rate-limiting step is the histidine uptake, it was found that no histidine was demonstrable in rat peritoneal mast cells by either quantitative analysis or paper chromatographic detection. Microadaptation of Hassall's method, based on conversion of l-histidine by histidase to urocanic acid and measurement of the latter by its absorbance at 277 nm, was made to permit determination of histidine in nanogram amounts in the presence of histamine. This adaptation was found reliable when compared with the o-phthalaldehyde method in estimation of l-histidine in serum and in insulin hydrolysate, and then it was applied to analysis of mast cells before and after l-histidine uptake in vitro. The adaptation should be generally useful in microanalysis of l-histidine in histologically and cytologically defined samples.

scholarly journals Hot-Stage Microscopy for Determination of API Particles in a Formulated Tablet

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Michal Šimek ◽  
Veronika Grünwaldová ◽  
Bohumil Kratochvíl
Keyword(s):  
Active Pharmaceutical Ingredient ◽  
Assessment Method ◽  
Hot Stage Microscopy ◽  
Tablet Disintegration ◽  
Before And After ◽  
In Vitro Assessment ◽  
Active Substances ◽  
Good Agreement

Although methods exist to readily determine the particle size distribution (PSD) of an active pharmaceutical ingredient (API) before its formulation into a final product, the primary challenge is to develop a method to determine the PSD of APIs in a finished tablet. To address the limitations of existing PSD methods, we used hot-stage microscopy to observe tablet disintegration during temperature change and, thus, reveal the API particles in a tablet. Both mechanical and liquid disintegration were evaluated after we had identified optimum milling time for mechanical disintegration and optimum volume of water for liquid disintegration. In each case, hot-stage micrographs, taken before and after the API melting point, were compared with image analysis software to obtain the PSDs. Then, the PSDs of the APIs from the disintegrated tablets were compared with the PSDs of raw APIs. Good agreement was obtained, thereby confirming the robustness of our methodology. The availability of such a method equips pharmaceutical scientists with an in vitro assessment method that will more reliably determine the PSD of active substances in finished tablets.

scholarly journals Evaluation of physicochemical and antioxidant properties of nanosized copolymeric micelles loaded with kaempferol

Pharmacia ◽  
2020 ◽  
Vol 67 (2) ◽  
pp. 49-54
Author(s):  
Krassimira Yoncheva ◽  
Nadia Hristova-Avakumova ◽  
Vera Hadjimitova ◽  
Trayko Traykov ◽  
Petar Petrov
Keyword(s):  
Antioxidant Activity ◽  
Propylene Oxide ◽  
Encapsulation Efficiency ◽  
Antioxidant Properties ◽  
In Vitro Release ◽  
Before And After ◽  
Poly Propylene ◽  
Vitro Release

The study was focused on the evaluation of two copolymers as micellar carriers for kaempferol delivery. The copolymers comprised identical hydrophilic blocks of poly(2-(dimethylamino)ethyl methacrylate and different hydrophobic blocks of either poly(ε-caprolactone) (PDMAEMA9-b-PCL70-b-PDMAEMA9) or poly(propylene oxide) (PDMAEMA13-b-PPO69-b-PDMAEMA13). The calculation of Flory-Huggins parameters and determination of encapsulation efficiency showed that PDMAEMA-b-PCL-b-PDMAEMA copolymer possessed higher capacity for kaempferol loading. The diameter of the micelles before and after lyophilization was not changed, suggesting that the micelles could be lyophilized and redispersed before administration. The in vitro release of kaempferol from PDMAEMA-b-PPO-b-PDMAEMA micelles was faster than the release from PDMAEMA-b-PCL-b-PDMAEMA micelles, probably due to the higher affinity of kaempferol to this copolymer. Further, the higher affinity resulted in a retention of antioxidant activity of kaempferol in the presence of DPPH and KO2 radicals. Thus, PDMAEMA-PCL-PDMAEMA was considered more appropriate carrier because of the higher encapsulation efficiency and preservation of antioxidant activity of the drug.

DETERMINATION OF PA INHIBITOR 1 (PA INHIBITOR ACTIVITY AND PA INHIBITOR 1 ANTIGEN) IN PLASMA BEFORE AND AFTER VENOUS OCCLUSION

1987 ◽  
Author(s):  
I Juhan-Vague ◽  
J Valadier ◽  
M C Alessi ◽  
J Ansaldi ◽  
M F Ailluad ◽  
...  
Keyword(s):  
Platelet Activation ◽  
Venous Occlusion ◽  
Inhibitor Activity ◽  
Post Surgery ◽  
In Vitro Activation ◽  
Before And After ◽  
High Level ◽  
Good Preparation

PA Inhibitor activity (PAIact-Verheijen’s method-U/ml) and PA Inhibitor 1 antigen (PAIlAg- Kruithof’s radioimmunoassay -ng/ml) were evaluated, on blood samples before (B) and after (A) venous occlusion (VO) (10 min) in order to analyse, in B-VO samples, the ratio (R=PAIlAg/PAIact) ' between the immunological and enzymatic material, and the change of PAIlAg levels after VO.The B-VO values (m ± SD) were determined from 111 plasmas : -86 with normal ( 12U/ml) PAIact levels = 3.7 ± 2.5 ; PAIlAg = 17.4 ± 10.1 ; R = 7.1 ± 6.2 (range 1.5 - 24 )-25 with high PAIact levels (15 post surgery, 10 obese patients)= 30.9± 19.3; PAIlAg = 75.3 ± 44.7 ; R = 2.7 ± 1.5 (range 1.3- 4.4). The correlation between the 2 dosages was r = 0.82 (p 0.01). In the 2 kinds of patients with high PAIact levels, a parallel high PAIlAg level was found. As the range of the ratio R was very large, patients were divided in 2 Groups : GrI : Normal R ( 7), n=81 (normal PAIact : n=57 ; high PAIact : n=24) and GrII : high R, n=30. The results for PAIact/PAIlAg/R were = GrI :12.6± 16.3/ 31.5±34.4/ 3.2 ± 1.5. GrII : 2.6±4.1/ 27.9 ±30.1/ 13.8±6.1. In GrII the platelet origin of inactive PAIlAg from in vitro activation of platelets could be demonstrated (high level of BTG lug/ml) in 50 % of cases. No in vitro platelet activation could be demonstrated in GrI. These results point out the necessity of a good preparation of the plasma (mainly 0-4°) for PAIlAg determination.The B and A-VO values were analysed from 60 subjects. Plasmas with in vitro activation of platelet determined by BTG levels had been discarded. No platelet activation occured with the VO. The results were not corrected with the PCV. PAIlAg B-VO/A-VO = 19.2 ± 15.1/ 26.9 ± 18.3. 36 subjects (60 % of total) had an increase in PAIlAg A-VO 20 % (mean increase = 62 %) . There was no correlation between basal values of PAIlAg and the increase after VO, and between PAIlAg increase and t-PA-Ag release. It is concluded that a weak increase of PAIlAg may occur after VO ; this increase is not parallel with t-PA release. The physiopathological significance of this increase of PAIlAg as yet to be evaluated.

Determination of cyanide and nitroprusside in blood and plasma.

1977 ◽  
Vol 23 (11) ◽  
pp. 1969-1975 ◽  
Author(s):  
F L Rodkey ◽  
H A Collison
Keyword(s):  
Clinical Medicine ◽  
Gas Transfer ◽  
Plasma Samples ◽  
Alkaline Ph ◽  
Cyanide Toxicity ◽  
Treated Sample ◽  
Blood Cyanide ◽  
In Vitro Stability

Abstract A procedure was refined for quantitative isolation of cyanide by gas transfer from acidified blood or plasma samples. The cyanide was trapped in dilute alkali and quantified as the pyridine/pyrazolone complex. The within-day coefficient of variation was 2%, which increased to about 2.5% for the day-to-day variation. Nitroprusside used as a hypotensive agent in clinical medicine provides a risk of cyanide toxicity when the rate of administration or the total amount of drug given is excessive. A procedure was developed for measuring nitroprusside in the plasma of man and animals. Nitroprusside in the sample is quantitatively converted to cyanide by incubation with cystein solution at slightly alkaline pH. Methemoglobin is added to combine with the cyanide formed and prevent its destruction. On acidification, the total amount of cyanide originally present as free cyanide or as nitroprusside is liberated as HCN, isolated by gas transfer into a sodium hydroxide trap, and quantified by spectrophotometry. Nitroprusside present in the sample is calculated from the increase in cyanide observed in the cysteine-treated sample compared to that obtained without cysteine treatment. The method has been used to estimate in vitro stability of nitroprusside in aqueous solution, blood, and plasma. Blood cyanide and plasma nitroprusside concentrations were measured when sodium nitroprusside was infused into a baboon. Over 90% of the nitroprusside in blood is present in the plasma, suggesting that the drug crosses the erythrocyte membrane slowly.

Determination of In Vitro Metatarsocuneiform Pressure Before and After Surgical Modification of the Great Toe

1995 ◽  
Vol 16 (2) ◽  
pp. 84-87 ◽  
Author(s):  
Richard A. Miller ◽  
Keikhosrow Firoozbakhsh ◽  
Fred Naraghi ◽  
James Ferries
Keyword(s):  
Great Toe ◽  
Before And After

STUDY ON THE EFFECT OF UNFRACTIONATED (UFH) AND LOW MOLECULAR WEIGHT (LMWH) HEPARINS ON THE DETERMINATION OF PROTEIN C ACTIVITY

1987 ◽  
Author(s):  
N Sala ◽  
J Fontcuberta
Keyword(s):  
Protein C ◽  
Plasma Samples ◽  
Protamine Sulphate ◽  
Vein Thrombosis ◽  
Antigen Elisa ◽  
Before And After ◽  
Control Plasma ◽  
Protein C Activity

In an attempt to see whether the presence of different heparins affected the determination of protein C activity (APC),this parameter was measured before and during treatment in 23 deep vein thrombosis patients that had been randomly treated with 3 different LMWH (Choay CY-216 and CY-222 and Kabi-2165) and UFH,for 10 days, Very low levels of APC (amidolytic assay that uses thrombin-thrombomodulin to activate the barium citrate eluted PC) were found in those patients receiving UFH and having an APTT more than 3 times that of control, as well as in those patients receiving LMWH CY-216 and having an APTT of only 8 to 10 seconds higher than that of control plasma, In patients receiving CY-222 and Kabi-2165, no significant differences were observed between APC levels before and during treatment, PC antigen (ELISA assay) was normal in all cases, In order to see if these low APC levels were due to interference of heparin with the assay and at which doses, control plasma pool was supplemented "in vitro" with 0 to 2.5 IU/ml (0 to 0,00252) of UFH and with 0 to 3 anti-Xa U/ml of LMWH CY-216, APTT, PCAg, APC and presence of ATI 11 in the barium citrate eluates (immunodiffusion), were determined in all plasma samples before and after treatment with protamine sulphate (PS) at 0,0032, The results showed that UFH, when not neutralized with PS, resulted in low APC values only at doses higher than 0,8 IU/ml, corresponding to an APTT of more than 3 times that of control plasma, LMWH CY-216 at doses above 1 anti-XaU/ml, corresponding to an APTT of only 10 seconds higher than that of control, also produced a gradual decrease in APC values, ATI 11 was clearly visualized in the barium citrate eluates of all those plasma samples having a low APC value, The addition of PS to all samples containing UFH resulted in a complete normalization of APC values, with almost normal AFTT values and disappearance of ATI 11 from the barium citrate eluates, On the contrary, addition of PS to plasma containing CY-216 resulted in low APC values and presence of ATI 11 in the eluates of those samples containing more than 4 antiXaU/ml, whose APTT still was about 10 seconds above that of control.It is concluded that at therapeutic doses not only UFH but also LMWH CY-216 interfere with the APC assay, probably through binding of hepar in-ATI 11 complexes to barium citrate and neutralization of the thrombin used to activate the barium citrate eluted PC, LMWH CY-222 and Kabi-2165, although increasing the APTT similarly to CY-216, do not seem to interfere with the APC assay, Protamine sulphate, at 0,0032 in plasma, completely abolishes the effect of UFH on APC assay but not that of LMWH CY-216, More studies are being performed to see if higher doses of PS can be used to neutralize the effect of this LMWH.

STUDIES ON SUSTAINED CONTRACEPTIVE EFFECTS WITH SUBCUTANEOUS POLYDIMETHYLSILOXANE IMPLANTS

1973 ◽  
Vol 73 (2) ◽  
pp. 347-359 ◽  
Author(s):  
G. Benagiano ◽  
M. Ermini ◽  
L. Carenza ◽  
P. Donini
Keyword(s):  
Urinary Excretion ◽  
Young Women ◽  
Ovarian Function ◽  
Megestrol Acetate ◽  
Bleeding Pattern ◽  
Experimental Conditions ◽  
The Third ◽  
Before And After

ABSTRACT Ovarian function was assessed in 10 healthy young women, before and after the insertion of 3 or 4 polydimethylsiloxane capsules filled with 20 mg of megestrol acetate. Each capsule released in vitro, approximately 20 μg/24 h of the hormone. Daily determination of the urinary excretion of FSH, LH, fractionated oestrogens and pregnanediol were performed in all subjects during one control cycle, the first and the third cycle after the insertion of the capsules. Out of 10, 8 control cycles were ovulatory according to all the parameters investigated. This compares with 15 ovulatory cycles out of a total of 20, examined after the insertion of the capsules. During treatment no changes were observed in the FSH excretion pattern; the mid-cycle LH peak was present in all ovulatory cycles, although it was usually much less evident under the action of megestrol acetate. The excretion of oestradiol was significantly increased in all subjects (P < 0.05) during the first cycle following implantation. Oestrone and oestriol excretion was also generally higher in patients bearing PDS capsules; however, this difference was not statistically significant. Pregnanediol levels were not affected by the treatment in all cycles considered to be ovulatory on the basis of all the parameters. The menstrual bleeding pattern did not change in the majority of cases. One patient had, during treatment with 3 capsules, two profuse break-through bleedings whereas another one became amenorrhoic two months after the insertion of 4 implants. It is concluded that megestrol acetate sustained release preparations do not inhibit ovulation under the experimental conditions used.

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