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"Bridging academic research and industrial applications, this is the first modern approach to relate fundamental research to the applied science of colloids. This text examines the role of colloid and interface science in pharmacy, as well as pharmaceutical formulations and drug delivery. It then goes on to treat pharmaceutical suspensions and emulsions, including multiple emulsions, as well as liposomes and the role of nanotechnology in drug delivery. A final section is devoted to the hot topic of stem cell research."

"Colloid and interface science in pharmaceutical research and development describes the role of colloid and surface chemistry in the pharmaceutical sciences. It gives a detailed account of colloid theory, and explains physicochemical properties of the colloidal-pharmaceutical systems, and the methods for their measurement.The book starts with fundamentals in part I, covering fundamental aspects of colloid and interface sciences as applied to pharmaceutical sciences and thus should be suitable for teaching. Parts II and III treat applications and measurements, and they explains the application of these properties and their influence and use for the development of new drugs."

"UK Colloids 2011, the first multi-day conference on the topic of colloid science held in the UK for many years, jointly organized by the RSC Colloid and Interface Science Group and the SCI Colloid and Surface Science Group. This title collects together a selection of 20 papers, mostly presented during the Conferenc"

"ABSTRAKSifat koloid lateks yang cenderung mengalami koagulasi mengakibatkan lateks sulit untuk dimodifikasi pada saat proses hidrogenasi. Hal ini disebabkan oleh sifat koloid lateks yang cenderung tidak stabil terhadap perlakuan temperatur, kecepatan pengadukan, dan penambahan zat kimia. Penelitian ini bertujuan mempelajari suatu kondisi proses yang optimum dengan mempertahankan kestabilan koloid untuk meningkatkan derajat hidrogenasi. Uji turbiditas dilakukan untuk mengetahui tingkat kekeruhan larutan lateks yang mengindikasikan terdispersinya koloid didalam larutan lateks. Sedangkan, uji viskositas dilakukan sebagai uji pendukung. Berdasarkan hasil penelitian dalam menentukan kondisi optimum stabilitas koloid pada fasa lateks dengan pengujian turbiditas dan viskositas, diketahui koloid cenderung stabil pada temperature 50?C, kecepatan aduk 200 rpm dan kadar karet kering KKK 20.

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ABSTRACTThe tendency to coagulate, which is the colloid characteristic of latex makes it difficult to be modified when hydrogenation process is running. This was caused by the latex colloid characteristic which is unstable to thermal treatment, stirring velocity, and the addition of chemical compounds. This research aims to learn the optimum process condition by maintaining the colloid stability to increase the hydrogenation degrees. Turbidity test was done to know the turbidity level of latex solution indicates the dispersed colloid inside the latex solution, while viscosity test was done as a supporting test. Based on the research result in determining the optimum condition of the colloid stability in the latex phase with the turbidity and viscosity test, colloid has the tendency to be stable at the temperature of 50oC, stirring speed of 200 rpm, and the dry rubber content of 20."

"Pencemaran limbah dapat merusak lingkungan sekitar dan menjadi tercemarnya logam berat oleh bahan kimia, misalnya suatu perairan. Logam berat yang banyak terdapat di perairan salah satunya adalah Pb. Pada percobaan ini dilakukan pengukuran menggunakan DGT yang dapat mengukur keberadaan logam spesi labil. Spesi labil dapat mewakili jumlah logam yang mungkin terserap biota. DGT yang terdiri dari diffusive layer dan binding layer diuji kemampuannya dalam menyerap spesi logam labil Timbal (II). DGT dengan binding gel Chelex maupun poli(asam)akrilat gel diuji pada variasi waktu pengukuran, konsentrasi larutan, pH, dan adanya EDTA. Waktu optimum penyerapan dalam DGT adalah 24 jam (CDGT : Clarutan 99,29%) untuk Chelex binding gel dan 24 jam (CDGT : Clarutan 44,98%) untuk poli(asam)akrilat gel. Pada konsentrasi 1 mg/L hingga 100 mg/L dapat terukur secara efektif, hanya saja ketika konsentrasi 100 mg/L penyerapannya sudah mendekati konsentrasi awal sehingga sudah mencapai optimum. DGT poli(asam)akrilat hanya dapat mengukur larutan uji secara efektif sampai konsentrasi 4,7411 mg/L, sedangkan pada konsentrasi 9,7946 mg/L mulai menurun. DGT dengan Chelex maupun poli(asam)akrilat binding gel optimum mengukur pada larutan dengan pH sekitar pH netral (±7). Dengan adanya EDTA, konsentrasi yang terukur DGT menjadi lebih kecil baik menggunakan Chelex maupun poli(asam)akrilat jika dibandingkan tanpa adanya EDTA. Logam Pb yang terserap dalam DGT untuk sampel air danau secara alamiah memberikan hasil konsentrasi yang kecil dibandingkan dengan adanya penambahan zat Pb 5 mg/L baik menggunakan Chelex maupun poli(asam)akrilat.

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Heavy metals contamination can pollute the waters and then damage the surrounding environment. Pb is one of the heavy metals in contaminant water. In this experiment, measurements were conducted using DGT to measure labile metal species. Labile species may represent the amount of metal that could be absorbed by biota. DGT diffusive layer and binding layer are tested for their capacity to absorb labile metal plumbum (II). DGT with a chelex binding gel and poly(acrylic acid) were tested for the effect of the measurement time, solution concentration, pH, and the presence of EDTA. Results of analysis using AAS showed that the optimum time for measurement of DGT is 24 hours (CDGT : Csolution 99,29%) for binding chelex gel and 24 hours (CDGT : Csolution 44,98%) for poly(acrylic acid) gel. At a concentration of 1 mg/L to 100 mg/L can be measured effectively, where the adsorption reached the optimum value when the initial concentration of approaching 100 mg/L. Poly(acrylic acid) DGT can only effectively measure the test solution until the concentration of 4,7411 mg/L, whereas at the concentration 9,7946 mg/L started to decline. Chelex-100 and DGT binding gel poly(acrylic acid) measure the optimum solution with a pH around neutral pH (+ 7). The presence of EDTA causes measured concentration (CDGT) either with using chelex and poly(acrylic acid) becomes smaller than those without EDTA addition. The adsorption of Pb in DGT for natural water lake to give smaller value than addition Pb 5 mg/L for chelex-100 and poly(acrylic acid)."

"Hidrogel merupakan polimer superabsorben yang dapat menyerap dan menahan sejumlah besar medium cair. Hidrogel kitosan-graft-poli(N-vinil pirrolidon) atau kitosan-graft-PNVP disintesis melalui proses polimerisasi radikal bebas. Polimer ini diikatsilangkan pada rantai cabang, rantai PNVP, dengan agen pengikat silang yang berbeda, yaitu N,N’-Metilen Bisakrilamida (MBA) dan Etilen Glikol Dimetakrilat (EGDMA). Kemampuan swelling hidrogel kitosan-graft-PNVP terikat silang dilakukan dengan merendamnya dalam media cair. Pengaruh jenis dan konsentrasi agen pengikat silang serta waktu reaksi terhadap daya absorbsi air telah diamati. Hidrogel yang terikat silang dengan EGDMA memperlihatkan rasio swelling lebih besar dibandingkan dengan hidrogel yang terikat silang dengan MBA. Kemampuan menyerap hidrogel yang terikat silang dengan EGDMA dapat mencapai 50% dari berat sebelum menyerap air. Produk ini dikarakterisasi menggunakan Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC) dan Scanning Electron Microscope (SEM).

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Hydrogels are superabsorbent polymer that it can be able to absorb and retain large amounts of aqueous fluids. Hydrogel chitosan-graft-poly(N-vinyl pirrolidone) or chitosan-graft-PNVP has been synthesized by free radical polymerization. It is synthesized by crosslinking in the branch chains, PNVP chains, with different crosslinking agents, i.e. N,N’-Methylene Bisacrylamide (MBA) dan Ethylene Glycol Dimethacrylate (EGDMA). The swelling behavior of the crosslingked chitosan-graft-PNVP was measured by immerse it in the water. The effect of different and concentration of crosslinked agents and also reaction time on water absorbency have been investigated. Crosslinked hydrogel by using crosslinker EGDMA had showed that swelling ratio is higher than crosslinked hydrogel by using crosslinker MBA. The swelling behavior of crosslinked hydrogel by using crosslinker EGDMA can absorb water until 50% from its weight before absorbed. Resulted hydrogels were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC) and Scanning Electron Microscope (SEM)."

"Pada penelitian ini dilakukan sintesis polimer hidrogel poli(N-isopropilakrilamida-ko-2-dimetilaminoetil metakrilat) (P(NIPAM-ko-DMAEMA)) yang mempunyai sifat responsif temperatur dan pH dengan menggunakan mekanisme polimerasi radikal bebas menggunakan inisiator ammonium persulfat (APS) dan agen pengikat silang N,N’-metilenbisakrilamida (MBA). Hidrogel P(NIPAM-ko-DMAEMA) dilakukan karakterisasi menggunakan fourier transform infrared (FTIR) dan didapatkan hilangnya puncak pada Csp2 pada gugus vinil monomer yang menandakan proses polimerisasi berhasil. Pada uji persen gel didapatkan bahwa semakin tinggi komposisi DMAEMA, persen gel akan semakin kecil berbanding terbalik dengan hal tersebut rasio swelling hidrogel akan semakin besar.  Pada uji swelling di berbagai temperatur didapatkan bahwa semakin tinggi temperatur, rasio swelling akan semakin kecil. Pada uji swelling di berbagai pH didapatkan bahwa semakin tinggi pH, rasio swelling akan semakin kecil. Hasil uji swelling di berbagai temperatur dan pH menunjukkan bahwa rasio swelling terbesar dimiliki oleh hidrogel P(NIPAM-ko-DMAEMA) dengan komposisi monomer NIPAM 30 mol% dan monomer DMAEMA 70 mol% serta komposisi agen pengikat silang MBA 2 mol%. Didapatkan bahwa hidrogel P(NIPAM30-ko-DMAEMA70) memiliki potensi sebagai penghantar bahan aktif dengan besar persen enkapsulasi metformin-HCl sebesar 65,304% w/w dan pelepasan sebesar 26,83% dalam buffer pH 6,8 pada temperatur 37.

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In this research, poly(N-isopropylacrylamide-co­-2-dimethylaminoethyl methacrylate) (P(NIPAM-co-DMAEMA)) hydrogels with temperature- and pH- responsive properties were synthesized by the mechanism of free-radical polymerization, using ammonium persulfate (APS) as initiator and N,N’-methylenebisacrylamide (MBA) as crosslinking agent. The P(NIPAM-co­-DMAEMA) hydrogels were characterized by using the Fourier Transform Infrared (FTIR) and resulting in the non appearence of Csp2 peak of the monomer vinyl structure that indicates the polymerization process success. The gel percentage tests concluded that the higher the DMAEMA composition, the gel percentage will be lower, in contrast with that, the swelling ration of the hydrogel will be higher. The swelling test on several scales of temperature identified that the higher the temperature is, the lower the swelling ratio will be. Correspondingly, the swelling test with various pHs exhibit that the higher the pH is, the lower the swelling ratio will be. It was discovered that the swelling tests on various temperatures and pHs result in the highest swelling ratio on P(NIPAM-co-DMAEMA) hydrogel with the composition of 30 mol% of NIPAM monomer, 70 mol% of DMAEMA, and 2 mol% of crosslinking agent. The P(NIPAM30-co-DMAEMA70) hydrogel is potential as a carrier to encapsulate 65.304% w/w metformin HCl with 26.83% release in buffer pH 6.8 at 37°C."