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Size exclusion chromatography Transmission electron microscopy (TEM)Brachytherapy or internal radiotherapy is one of many methods used for treatment of cancer. This modality requires an agent with radionuclides that emits α or β particle with a proper energy. 198Au (99% β max = 0.96 MeV and t 1/2 = 2.69 days) is one of radionuclides that has been considered to be effective for the abovementioned purpose. The purpose of this research was to synthesis and characterize poly(amidoamine) (PAMAM) G3.0 dendrimers encapsulated 198 Au nanoparticles as a new brachytherapy agent. PAMAM G3.0 dendrimers encapsulated 198 Au nanoparticles was successfully synthesized by a bottom-up method using sodium borohydride as a reductor. Purification was then performed by a size exclusion chromatography in order to separate large Au nanoparticles that were formed outside the cavity of PAMAM G3.0 dendrimers. Prior to the synthesis of PAMAM G3.0 dendrimers encapsulated 198 Au nanoparticles, the synthetic procedure was first established by using a non-radioactive Au. The PAMAM G3.0 dendrimers encapsulated Au nanoparticles produced was then characterized by using an UV-Vis spectroscopy, a transmission electron microscopy (TEM), particle size analyzer (PSA), and an atomic absorption spectroscopy (AAS). Characterization results revealed that PAMAM G3.0 dendrimers encapsulated Au nanoparticles that were prepared from a reaction mixture of PAMAM G3.0 dendrimers and Au HAuCl 4 with mol ratio of 2.8, was found to be a proper formula. It produced PAMAM G3.0 dendrimers encapsulated Au nanoparticles with diameter of 1.743 nm, spheris, uniform and drug loading value of 26.34%. This formula was then used in synthesis using radioactive Au, 198 Au. Characterization results of PAMAM G3.0 dendrimers encapsulated 198 Au nanoparticles gave a radiochemical purity of 99.4% and zero charge.

Penentuan Kemurnian Radiokimia 99mTc-MIBI dengan Cepat Dan Praktis menggunakan Metoda Ekstraksi. Pengujian radiokimia umumnya menggunakan metoda kromatografi lapis tipis (KLT), akan tetapi memerlukan waktu pengujian lama. Oleh karena itu, perlu alternatif menggunakan metoda ekstraksi yang lebih praktis dan cepat. Pengujian dilakukan dengan cara 99mTc-MIBI diekstraksi menggunakan campuran salin dan chloroform dengan perbandingan volume = 1:1.  Campuran diekstraksi sehingga terpisah antara 99mTc-MIBI dan pengotornya, yaitu 99mTc-MIBI dalam fasa organik (Chloroform) sedangkan 99mTcO2 dan 99mTcO4- keduanya dalam fasa air (salin). Kemudian, masing-masing dicuplik dengan volume yang sama dan diukur radioaktivitasnya menggunakan Gamma Ionisation Chamber dan dihitung kemurnian radiokimianya. Hasil ekstraksi dibandingkan dengan pengujian menggunakan metoda baku KLT. Hasil penelitian menunjukkan bahwa pengujian radiokimia  kit 99mTc-MIBI menggunakan kedua metoda tersebut hasilnya hampir sama, yaitu =98,34%±0,65 (metoda baku KLT) dan 97,15%±0,56 (metode ekstraksi) dengan kepresisian pengukuran yang baik, yaitu RSD <1% (RSD metode baku KLT=0,65% dan metode ekstraksi 0,56%). Waktu pengujian yang diperlukan dengan metoda ekstraksi = 20 menit  dan metoda baku KLT =180 menit. Hasil ini menunjukkan bahwa metoda ekstraksi dapat digunakan sebagai alternatif dalam pengujian radiokimia kit MIBI. Keunggulan metoda ekstraksi adalah waktu pengujian lebih cepat dibandingkan metoda KLT.Kata kunci : Kemurnian Radiokimia, 99mTc-MIBI, metoda ekstraksi, metoda Kromatografi Lapis Tipis

This article discusses the issue of cartels in business competition law. The discussion took the case of a cartel carried out by a well-known Swedish truck and bus manufacturer, Scania. In 2017, European Commission member on competition, Margrethe Vestager stated, the European Commission had found that Scania violated EU antitrust rules. The company colluded for 14 years with five other truck manufacturers on pricing trucks and to charge new technology to meet stricter emissions rules. According to the European Commissioner, Scania has been practicing cartels since 1997 and has been going on for 14 years. Scania colluded with five other companies, namely: MAN (Germany), DAF (Netherlands), Daimler (Germany), Iveco (Italy), and Volvo (Sweden)/Renault (France). The case will be discussed using a qualitative method, with discussions on business competition law, cartel theory, and the theory of proof of cartel business competition acts. It is not easy to prove the existence of a cartel and cartel actors can exercise their right not to receive sanctions by appealing and defending their arguments. Solving the cartel, takes a long time and allows developing other problems.

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.