Human identification from biological material is largely dependent on the ability to characterize genetic polymorphisms in DNA. Unfortunately, DNA can degrade in the environment, sometimes below the level at which it can be amplified by PCR. Protein however is chemically more robust than DNA and can persist for longer periods. Protein also contains genetic variation in the form of single amino acid polymorphisms. These can be used to infer the status of non-synonymous single nucleotide polymorphism alleles. To demonstrate this, we used mass spectrometry-based shotgun proteomics to characterize hair shaft proteins in 66 European-American subjects. A total of 596 single nucleotide polymorphism alleles were correctly imputed in 32 loci from 22 genes of subjects’ DNA and directly validated using Sanger sequencing. Estimates of the probability of resulting individual non-synonymous single nucleotide polymorphism allelic profiles in the European population, using the product rule, resulted in a maximum power of discrimination of 1 in 12,500. Imputed non-synonymous single nucleotide polymorphism profiles from European–American subjects were considerably less frequent in the African population (maximum likelihood ratio = 11,000). The converse was true for hair shafts collected from an additional 10 subjects with African ancestry, where some profiles were more frequent in the African population. Genetically variant peptides were also identified in hair shaft datasets from six archaeological skeletal remains (up to 260 years old). This study demonstrates that quantifiable measures of identity discrimination and biogeographic background can be obtained from detecting genetically variant peptides in hair shaft protein, including hair from bioarchaeological contexts.

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β‐Glucuronidase enzymes have been attached to a porous silicon surface through a direct silicon–carbon bond based linking system (see Figure). The attached enzymes display high activity and the photoluminescent (PL) properties and surface stability of the porous silicon are retained. Quenching of the PL is observed upon enzymatic breakdown of the substrate, leading to the possibility of a new class of chemical and biological sensors.

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Molecular imprinting has been used to create synthetic receptor sites for a series of chiral benzodiazepines. A detailed HPLC analysis of binding properties using molecularly imprinted polymers (MIPs) as the stationary phase showed that binding, as measured by chromatographic retention, shows significant dependence on the chiral match or mismatch. In addition, the shape and spatial orientation of functionality of the imprinted binding site is also critical for recognition. Imprinted polymers, therefore, are not only able to discriminate between enantiomers of the imprinted molecule, they also demonstrate an ability to discriminate between a wide range of enantiomers of structurally related molecules that have not been imprinted. The ability of MIPs to discriminate between enantiomers of molecules in favor of the imprinted absolute configuration, even as the structural homology between the enantiomers and the original template decreases, indicates that the synthetic benzodiazepine receptors may serve as crude mimics of the natural receptor.

A new procedure for creating macromolecular receptors for peptides using molecular imprinting has been developed. The polymeric receptor exhibits selective uptake of specific N-terminal histidine containing sequences of simple dipeptides. The polymerization and binding are carried out in water. The approach utilizes a strong Ni(II)-His binding to attract the N-terminus histidine of the dipeptide to the polymer surface and secondary interactions between peptide and polymer to discriminate between the peptide sequence. These developments are enabled by utilizing an aqueous based monomer formulation that includes N,N′-ethylenebis(acrylamide) as a water-soluble cross-linking monomer and a polymerizable NTA ligand, which can be used to incorporate nickel and other metals into these polyacrylamides. The Ni-NTA complex provides a strong histidine binding site that draws the dipeptide to the polymer surface. Mild polymerization conditions that utilize low concentrations of water-soluble initiator and low-temperature result in quantitative polymer yields. Variation of monomer composition reveals an optimum cross-linking for achieving maximum selectivity for these polymers.

Chemical warfare agents (CWAs) are unarguably one of the most feared toxic substances produced by mankind. Their inception in conventional warfare can be traced as far back as the Middle Ages but their full breakthrough as central players in bellic conflicts was not realized until World War I. Since then, more modern CWAs along with efficient methods for their manufacture have emerged and violently shaped the way modern warfare and diplomatic relations are conducted. Owing to their mass destruction ability, counter methods to mitigate their impact appeared almost immediately on par with their development. These efforts have focused on their efficient destruction, development of medical countermeasures and their detection by modern analytical chemistry methods. The following review seeks to provide the reader with a broad introduction on their direct detection by gas chromatography-mass spectrometry (GC-MS) and the various sample derivatization methods available for the analysis of their degradation products. The review concentrates on three of the main CWA classes and includes the nerve agents, the blistering agents and lastly, the incapacitating agents. Each section begins with a brief introduction of the CWA along with discussions of reports dealing with their detection in the intact form by GC-MS. Furthermore, as products arising from their degradation carry as much importance as the agents themselves in the field of forensic analysis, the available derivatization methods of these species are presented for each CWA highlighting some examples from our lab in the Forensic Science Center at the Lawrence Livermore National Laboratory.

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