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1.
Comb Chem High Throughput Screen ; 16(7): 572-83, 2013 Jun 28.
Article in English | MEDLINE | ID: mdl-23477497

ABSTRACT

Four fluorescent tricyclic basic dyes with two hollow organic capsules namely cucurbit[n]urils (CB[n]), n = 7 and 8, compose the chemical tongue that is examined for α-amino acids recognition. This array is able to identify and discriminate 18 α-amino acids up to 10-4 M without the need of enzyme activation. The paper shows the importance of the classification technique employed in order to reach the highest recognition rate at this concentration.


Subject(s)
Amino Acids/chemistry , Tongue , Humans , Reproducibility of Results , Support Vector Machine
2.
Science ; 333(6046): 1131-4, 2011 Aug 26.
Article in English | MEDLINE | ID: mdl-21868673

ABSTRACT

The formation of mesopores in microporous zeolites is generally performed by postsynthesis acid, basic, and steam treatments. The hierarchical pore systems thus formed allow better adsorption, diffusion, and reactivity of these materials. By combining organic and inorganic structure-directing agents and high-throughput methodologies, we were able to synthesize a zeolite with a hierarchical system of micropores and mesopores, with channel openings delimited by 28 tetrahedral atoms. Its complex crystalline structure was solved with the use of automated diffraction tomography.

3.
Phys Chem Chem Phys ; 13(10): 4674-8, 2011 Mar 14.
Article in English | MEDLINE | ID: mdl-21283845

ABSTRACT

Evolutionary algorithms have proved to be efficient for solving complicated optimization problems. On the other hand, the many-core architecture in graphical cards "General Purpose Graphic Processing Unit" (GPGPU) offers one of the most attractive cost/performance ratio. Using such hardware, the manuscript shows how an efficiently implemented genetic algorithm with a simple fitness function allows boosting the determination of zeolite structures. A case study is presented.

4.
Chemistry ; 16(15): 4489-95, 2010 Apr 19.
Article in English | MEDLINE | ID: mdl-20309968

ABSTRACT

γ-Hydroxybutyric acid (GHB), a colourless, odourless and tasteless chemical, has become one of the most dangerous illicit drugs of abuse today. At low doses, this drug is a central nervous system depressant that reduces anxiety and produces euphoria and relaxation, sedating the recipient. There is an urgent need for simple, easy-to-use sensors for GHB in solution. Here, we present a colorimetric sensor array based on supramolecular host-guest complexes of fluorescent dyes with organic capsules (cucurbiturils) for the detection of GHB.


Subject(s)
Central Nervous System Depressants/analysis , Hydroxybutyrates/analysis , Illicit Drugs/analysis , Rape , Central Nervous System Depressants/chemistry , Colorimetry/methods , Hydroxybutyrates/chemistry , Molecular Conformation
5.
Chemistry ; 15(17): 4258-69, 2009.
Article in English | MEDLINE | ID: mdl-19301338

ABSTRACT

Few solutions that aim to identify crystalline materials from the analysis of powder X-ray diffraction (XRD) data have been reported to date. A careful inspection of the powder XRD data, and the corresponding highlight of specific failures when it has been used for the determination of the crystallographic phases of zeolites among mixtures, has allowed the creation of the recently proposed strategy: adaptable time warping (ATW). Herein, the design process is thoroughly detailed in a step-by-step manner, which allows a deep understanding of the motivations, improvements, and the resulting remarkable properties of our methodology. Because the use of high-throughput (HT) techniques for the discovery or for increasing the breadth of the synthetic routes of new microporous crystalline structures makes the reliability of search-match methods a critical factor to be assessed, a meticulous evaluation of the reliability and the robustness is provided and supported by both empirical comparisons and mathematical proof. The results offered by our methodology, which clearly outperforms the well-established solutions, open the way towards total automation of such a routine procedure, eliminating laborious and time-consuming controls, preliminary treatments, and settings. Consequently, the proposed solution is of great interest and appears to be very promising, not only because of the numerous potential applications of XRD in materials science, but also the possible expansion of the solution to several other characterization techniques.

6.
Comb Chem High Throughput Screen ; 11(4): 266-82, 2008 May.
Article in English | MEDLINE | ID: mdl-18473737

ABSTRACT

This study shows how chemistry knowledge and reasoning are taken into account for building a new methodology that aims at automatically grouping data having a chronological structure. We consider combinatorial catalytic experiments where the evolution of a reaction (e.g., conversion) over time is expected to be analyzed. The mathematical tool has been developed to compare and group curves taking into account their shape. The strategy, which consists on combining a hierarchical clustering with the k-means algorithm, is described and compared with both algorithms used separately. The hybridization is shown to be of great interest. Then, a second application mode of the proposed methodology is presented. Once meaningful clusters according to chemist's preferences and goals are successfully achieved, the induced model may be used in order to automatically classify new experimental results. The grouping of the new catalysts tested for the Heck coupling reaction between styrene and iodobenzene verified the set of criteria "defined" during the initial clustering step, and facilitated a quick identification of the catalytic behaviors following user's preferences.


Subject(s)
Cluster Analysis , Combinatorial Chemistry Techniques/methods , Models, Chemical , Algorithms , Catalysis , Iodobenzenes/chemistry , Kinetics , Styrene/chemistry
7.
J Comb Chem ; 8(3): 304-14, 2006.
Article in English | MEDLINE | ID: mdl-16676999

ABSTRACT

One of the main problems in high-throughput research for materials is still the design of experiments. At early stages of discovery programs, purely exploratory methodologies coupled with fast screening tools should be employed. This should lead to opportunities to find unexpected catalytic results and identify the "groups" of catalyst outputs, providing well-defined boundaries for future optimizations. However, very few new papers deal with strategies that guide exploratory studies. Mostly, traditional designs, homogeneous covering, or simple random samplings are exploited. Typical catalytic output distributions exhibit unbalanced datasets for which an efficient learning is hardly carried out, and interesting but rare classes are usually unrecognized. Here is suggested a new iterative algorithm for the characterization of the search space structure, working independently of learning processes. It enhances recognition rates by transferring catalysts to be screened from "performance-stable" space zones to "unsteady" ones which necessitate more experiments to be well-modeled. The evaluation of new algorithm attempts through benchmarks is compulsory due to the lack of past proofs about their efficiency. The method is detailed and thoroughly tested with mathematical functions exhibiting different levels of complexity. The strategy is not only empirically evaluated, the effect or efficiency of sampling on future Machine Learning performances is also quantified. The minimum sample size required by the algorithm for being statistically discriminated from simple random sampling is investigated.


Subject(s)
Algorithms , Computer Simulation , Computing Methodologies , Neural Networks, Computer , Catalysis , Statistics as Topic
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