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Soil is of particular interest to the forensic community because it can be used as valuable associative evidence to link a suspect to a victim or a crime scene. Liquid chromatography is a powerful analytical tool for organic compound analysis. Recently, high-performance liquid chromatography (HPLC) has proven to be an efficient method for forensic soil analysis, especially in discriminating soils from proximity locations. However, ultra-performance liquid chromatography (UPLC), which is much more sensitive than HPLC, has never been explored in this context. This study proposed a UPLC method for profiling non-volatile organic compounds in three Malaysian soils (red, brown and yellowish-brown soils). The three soils were analysed separately to assess the effects of individual chromatographic parameters: (a) elution programme (isocratic vs. two gradient programmes); (b) flow rate (0.1 vs. 0.2 mL/min); (c) extraction solvent (acetonitrile vs. methanol) and (d) detection wavelength (230 vs. 254 nm). The injection volume and total run time were set to 5 µL and 35 min, respectively. Consequently, each soil sample gave 24 different chromatograms. Results showed that the most desirable chromatographic parameters were (a) isocratic elution; (b) flow rate at 0.2 mL/min and (c) acetonitrile extraction solvent. The proposed UPLC system is expected to be a feasible method for profiling non-volatile organic compounds in soil, and is more chemical-efficient than a comparable HPLC system. KEY POINTS• UPLC is a chemical-efficient analytical method for profiling non-volatile organic compounds in soil. • Mobile phase rich in acetonitrile promotes separation of non-volatile organic compounds in soil. • Isocratic elution is more desirable than gradient elution in producing a high-quality chromatogram.

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Ultra-performance liquid chromatography (UPLC) is more effective than high performance liquid chromatography in terms of analysis speed and sensitivity. This paper presents a feasibility study on forensic red pen inks analysis using UPLC. A total of 12 varieties of red ballpoint pen inks were purchased from selected stationary shop. For each variety, four different individual pens were sampled to provide intra-variability within a particular variety of pen. The proposed approach is very simple that it only involved limited analysis step and chemicals. A total of 144 chromatograms were obtained from red ink entries extracted with 1.5 mL 80 % (v/v) acetonitrile. Peaks originated from pen inks were determined by comparing the chromatograms of both blank paper and blank solvent against that of ink samples. Subsequently, one-way ANOVA was conducted to discriminate all 66 possible pairs for red pen inks. Results showed that the proposed approach giving discriminating power of 95.45 %. The outcome of the study indicates that UPLC could be a fast and simple approach to red ballpoint pen inks analysis.Keywords: forensic ink analysis, ballpoint pen inks, ultra-performance liquid chromatography Abstrak Kromatografi cecair berprestasi Ultra (UPLC) adalah lebih berkesan dari kromatografi cecair berprestasi tinggi dari segi kelajuan analisis dan kepekaan. Kertas ini mempersembahkan kajian kebolehlaksanaan pada analisis dakwat pen merah menggunakan UPLC. Sebanyak 12 jenis dakwat pen mata bulat merah dibeli dari kedai alat tulis yang terpilih. Untuk setiap jenis, empat batang pen telah disampel untuk memberi maklumat tentang intra-variasi bagi suatu jenis pen. Pendekatan yang dicadangkan adalah mudah kerana ia hanya melibatkan langkah analisis dan bahan kimia yang terhad. Sejumlah 144 kromatogram telah diperolehi dari dakwat tulisan merah yang diekstrak dengan 1.5 mL 80 % (v/v) asetonitril. Puncak yang berasal dari dakwat pen ditentukan melalui perbandingan antara kromatogram kertas kosong dan pelarut kosong dengan yang diperolehi dari sampel dakwat. Seterusnya, ujian ANOVA sehala telah dijalankan untuk membezalayan kesemua 66 pasangan dakwat pen merah yang terbentuk. Keputusan menunjukkan pendekatan yang dicadangkan memberi 95.45 % kuasa pembezalayan. Hasil kajian ini menunjukkan UPLC dapat dijadikan satu pendekatan yang cepat dan mudah untuk analisis dakwat pen mata bulat merah.

Malaysia telah berikrar untuk memberi komitmen dalam menangani perubahan iklim di peringkat global dengan menjadi negara rendah karbon pada tahun 2050. Masyarakat selaku pengguna utama karbon yang menyumbang kepada pelepasan karbon ke persekitaran melalui aktiviti seharian dilihat memainkan peranan yang amat penting untuk merealisasikan misi rendah karbon tersebut. Artikel ini ditulis untuk merungkai kesediaan dan potensi masyarakat di Malaysia merealisasikan matlamat negara rendah karbon. Pendekatan ulasan mendalam berasaskan pembacaan buku-buku ilmiah, jurnal tersohor dan rujukan atas talian dijadikan asas dalam merungkai dan menjawab persoalan tajuk yang dibincangkan. Dapatan menunjukkan bahawa masyarakat Malaysia mampu dan berpotensi untuk merealisasikan aspirasi pengurangan emisi karbon sebanyak 30% menjelang tahun 2050 berdasarkan kepada kebersediaan masyarakat terhadap langkah-langkah mengurangkan emisi karbon yang didokong oleh Dasar-dasar kerajaan. Kesimpulannya masyarakat di Malaysia dipercayai memiliki kesediaan dan potensi untuk merealisasikan matlamat negara rendah karbon menjelang tahun 2050.