Resonance light scattering technique for the determination of proteins with resorcinol yellow and OP

A new resonance light scattering (RLS) assay of proteins is presented. In the citric acid-NaOH (pH 2.35) buffer, the RLS of Resorcinol yellow (RY)-protein system can be greatly enhanced by addition of nonionic surfactant OP, owing to the interaction between OP and RY-protein. The enhanced RLS is in proportion to the concentration of proteins in the range 0.02-4.0 mug ml(-1) for both bovine serum albumin (BSA) and bovine hemoglobin (HEM), the detection limits were 10.4 ng ml(-1) (S/N=3) for BSA and 11.4 ng ml(-1) (S/N=3) for HEM. Samples were determined satisfactorily.     

Resonance double light scattering method for the determination of proteins with morin-CTMAB

A new determination method of proteins with the limit of determination at nanogram levels is proposed by using a common spectrofluorimeter to detect intensity of resonance double line scattering (RDLS). Proteins including bovine serum albumin (BSA), human serum albumin (HSA) can combine with morin and cetyltrimethylammonium briomide (CTMAB) in the pH range 7.0-8.0 and produce enhanced RDLS signal at lambda(ex)/lambda(em) 305.0/610.0 nm. Optimization conditions for the morin-protein-CTMAB interaction were tested. In the studied system, BSA/CTMAB/morin = 1:2:3. The association constant of morin with BSA is 5.2 x 10(4). Under the optimum conditions, the linear range is 7.5 x 10(-8)-1.0 x 10(-5) g/ml for BSA, 2.5 x 10(-8)-5.0 x 10(-6) g/ml for HSA. The detection limits (S/N = 3) are 66.0 ng/ml for BSA and 23.0 ng/ml for HSA, respectively. Four synthetic samples were analyzed satisfactorily.     

钍试剂Ⅱ与蛋白质作用的共振光散射特征及微量蛋白质的光散射测定

研究了钍试剂Ⅱ与蛋白质在pH 4 3条件下作用的共振光散射特征 ,并以此建立了测定微量蛋白质的新方法。用普通荧光分光光度计测量了这一体系的共振光散射光谱 ,考察了影响因素。在最佳实验条件下 ,牛血清白蛋白 (BSA)浓度在 0mg/L～ 1 0 0mg/L范围内成线性关系。方法已用于尿中微量蛋白质的测定     

Resonance light scattering technique for the determination of protein with rutin and cetylpyridine bromide system

A new resonance light scattering (RLS) assay of protein is presented. In Tris-NaOH (pH = 10.93) buffer, the RLS of rutin-cetylpyridine bromide (CPB) system can be greatly enhanced by protein, including bovine serum albumin (BSA) and human serum albumin (HSA). The enhanced RLS intensities are in proportion to the concentration of proteins in the range of 5 x 10(-9) to 2.5 x 10(-6) g ml(-1) for BSA and 2.5 x 10(-8) to 3.5 x 10(-6) g ml(-1) for HSA. The detection limits (S/N = 3) are 3.0 ng ml(-1) for BSA and 10.0 ng ml(-1) for HSA. Samples are determined satisfactorily.     

维多利亚蓝B瑞利光散射技术测定阿魏酸

基于阿魏酸与维多利亚蓝B在中性介质中形成离子缔合物,导致瑞利光散射增强,建立了一种测定阿魏酸的分析方法。研究了离子缔合物反应的适宜条件,结果表明:在优化的条件下,阿魏酸浓度在5.60×10-7~1.34×10-5mol/L范围内与瑞利散射光的增强呈良好的线性关系,方法的检出限为3.26×10-7mol/L。已用于实际样品中阿魏酸的测定。     

Resonance light scattering method for the determination of anionic surfactant with acridine orange

The resonance Rayleigh scattering (RRS), second-order scattering (SOS) and frequency-double scattering (FDS) spectra of sodium dodecylbenzene sulfonate (SDBS) (anionic surfactant (AS)) with acridine orange (AO) system were studied. Experimental results showed that when lambda(em) = lambda(ex) = 537 nm, the RRS peak of AO was greatly enhanced with the increase of SDBS concentration at a pH range of 1.8-4.0. The linear range of the calibration curve for SDBS was 0.028-8.71 mg L(-1) with a detection limit of 8.36 microg L(-1) when the AO concentration was 2.5 x 10(-5)mol L(-1). The method has been applied to the determination of trace amount of AS in environmental water samples with satisfactory results. In addition, when lambda(em) = 321 nm and lambda(ex) = 642 nm, the intensity of FDS was proportional to the SDBS concentration ranging from 0.014 to 8.71 mg L(-1) and the correlation coefficient was 0.993 with a detection limit of 4.31 microg L(-1); when lambda(em) = 642 nm and lambda(ex) = 321 nm, the intensity of SOS was proportional to the SDBS concentration ranging from 0.050 to 8.71 mg L(-1), and the correlation coefficient was 0.993 with a detection limit of 14.9 microg L(-1).     

Resonance light scattering technique used for biochemical and pharmaceutical analysis

By coupling and scanning simultaneously excitation and the emission monochromators of a common spectrofluorometer, enhanced resonance light scattering (RLS) signals could be obtained. The enhanced RLS signals could be used for designating bio-assemblies, aggregation species, and analytical purposes. Herein, we review the reports since the year of 2000 concerning the biochemical and pharmaceutical analysis with the RLS measurements, and discuss the possible developments of this technique.     

Determination of proteins with tetracarboxy manganese(II) phthalocyanine by resonance light scattering technique

A novel method for the determination of proteins by using tetracarboxy manganese(II) phthalocyanine (MnC4Pc) as a resonance light scattering (RLS) probe has been developed. At pH 3.0 Britton-Robinson (B-R) buffer solution, the RLS intensity of MnC4Pc at 385 nm is greatly enhanced in the presence of proteins. The effects of pH, reaction time, concentration of MnC4Pc and interfering substances on the enhanced RLS intensity are investigated, respectively. Under optimal conditions, the linear ranges of the calibration curves are 0-2.00 microg mL(-1) for bovine serum albumin (BSA) and human serum albumin (HSA), 0.0-1.75 microg mL(-1) for human-IgG and ovalbumin, with a detection limit of 16.37 ng mL(-1) BSA, 17.62 ng mL(-1) HSA, 19.41 ng mL(-1) human-IgG and 20.72 ng mL(-1) ovalbumin. The method has been applied to the determination of total proteins in human serum samples collected from a hospital and the results are in good agreement with those reported by the hospital.     

罗丹明B共振光散射法测定马丙共聚物

建立了共振光散射法测定马丙共聚物的新方法.在B-R缓冲溶液中,罗丹明B与马丙共聚物结合形成离子缔合物并产生强烈共振光散射增强效应,其最大散射峰位于372 nm.研究了pH、罗丹明B浓度、反应时间和温度对散射峰的影响,结果表明在pH1.5～2.0的B-R缓冲体系中,1.0×10-3 mol /L罗丹明B用量为1.5 mL...     

樱桃红共振光散射光谱法测定牛血清白蛋白

研究了以樱桃红为共振光散射探针测定牛血清白蛋白的分析方法。在pH 3.58的BR缓冲溶液中,樱桃红与牛血清白蛋白(BSA)相互作用形成复合物,导致共振光散射(RLS)光谱明显增强,最大RLS峰位于340 nm处。由此建立检测痕量BSA的新方法。在优化实验条件下,RLS强度与BSA浓度的线性范围为1.0～60.0μg/mL,检出限为0.15μg/mL。方法可用于牛尿样品的分析。     

藉L-半胱氨酸包覆的ZnS纳米粒子的共振光散射定量分析蛋白质

合成和表征了功能性L-半胱氨酸包覆的ZnS纳米粒子。在pH5．12的NaAc-HAc溶液介质中,L-半胱氨酸包覆ZnS纳米粒子于波长308．0nm处出现共振光散射峰。一定量蛋白质的加入能明显增强体系的共振光散射,且峰强度增加值与蛋白质浓度间存在良好线性关系,据此建立了一种灵敏的测定微量蛋白质的方法。用L-半胱氨酸包覆ZnS纳米粒子作为探针,不仅克服了有机染料可能出现的光漂白等缺点,而且本身不具毒性。该法用于人血清试样中总蛋白的测定,其结果与临床数据一致。     

Determination of proteins with Alizarin Red S by Rayleigh light scattering technique

A new protein determination method by enhanced Rayleigh light scattering (RLS) technique has been developed. In acid condition (pH=3.60), RLS of 1,2-dihydroxyanthraquinone-3-sulfonate (Alizarin Red S) can be greatly enhanced by addition of proteins, resulting in two characteristic peaks, 360 and 505 nm, respectively. The new protein assay is based on the RLS enhancement and spectrum change. The optimum condition for the reaction was investigated. The linear range is 0.20-24.9 μg ml⁻¹ for BSA and 0.20-15.5 μg ml⁻¹ for HSA. The detection limits (S/N=3) are 9.59 ng ml⁻¹ for BSA and 9.51 ng ml⁻¹ for HSA. The results of determination for human serum samples were comparable to those obtained by Bradford method. The binding stoichiometry was determined.     

Determination of proteins by flow injection analysis coupled with the Rayleigh light scattering technique

A novel flow injection analysis (FIA) method with Rayleigh light scattering (RLS) detection was developed for the determination of protein concentrations. This method is based on the weak intensity of RLS of p-nitrohenzene-azo-3,6 disulfo-1-amino-8-naphthol-7-azo-benzene disodium salt (Amide Black-10B) which can be enhanced by addition of protein in weakly acidic solution. It has proved that the application of this method to quantify the proteins by using human serum albumin was available in real samples. In addition, this method is very sensitive (the determination limits are 0.11 μg/mL for human serum albumen (HSA) and 0.85 μg/mL for bovine serum albumen, BSA), simple, rapid and tolerance of most interfering substances. The FIA-RLS method was more stabile than the general RLS method and the average R.S.D. value of FIA-RLS less than general RLS. The effects of different interfering substances will be also examined. The amount of proteins in human serum sample was determined and the maximum relative error was no more than 3.00% as well as the recovery was between 94.9 and 105.9%.     

Resonance Rayleigh scattering method for the determination of cationic surfactants with chromium(VI)-iodide system.

A method for detecting and identifying cationic surfactant in some chemical samples for daily use that include Head & Shoulder Ampoule and Slek Shower Lotion has been developed. In an acid medium, chromium(VI) oxidizes I(-) to produce I(2), I(2) binds excess of I(-) to form I(3)(-), and I(3)(-) can further react with a cationic surfactant (CS) (such as cetyldimethyl benzylammonium chloride (CDBAC), Zephiramine (Zeph), cetylpyridinium bromide (CPB), tetradecyl pyridinium bromide (TPB) and cetyltrimethylammonium bromide (CTAB)) to form ion-association complexes [CS][I(3)]. This results in a significant enhancement of resonance Rayleigh scattering (RRS) and appearance of new RRS spectra. The RRS spectral characteristics of the ion-association complexes, the influencing factors and the optimum conditions of the reactions have been investigated. The intensities of RRS are directly proportional to the concentration of CS. CS in samples are collected using a treated anion exchange column and subsequently complexed by I(3)(-); then the RRS intensities of CS complex are determined at 495 nm. The reactions have high sensitivities, and their detection limits are 7.05 - 9.62 ng/mL for different CS. The effects of foreign substances are investigated and the results show that the method has good selectivity.     

Resonance Rayleigh-scattering method for the determination of proteins with some monoazo dyes of chromotropic acid.

In a weak acid medium, protein reacts with a monoazo dye of chromotropic acid, such as Chromazol KS (CALKS), Acid Chrome Dark Blue (ACDB), Chrome Blue SE (CBSE), Acid Chrome Blue K (ACBK), Chlorophosphonazo I (CPAI), Arsennazo I (AAI) and Chromotrope 2R (CT2R), to form a combination product. This results in a significant enhancement of the resonance Rayleigh-scattering (RRS) intensity, and the corresponding RRS spectrum appears. The characteristics of the RRS spectra of the combination products and the optimum conditions for the reactions were investigated. The intensity of RRS is directly proportional to the concentration of protein in a certain range. The RRS methods have high sensitivity for the determination of protein, the detection limits for bovine serum albumin (BSA) are 10.0 - 30.2 ng/ml, and the sensitivity order is CALKS > AAI = CPAI > ACBK = CT2R > ACDB > CBSE. The selectivity for CALKS has been examined, and the method was applied to the determination of a microg amount of protein in a synthetic sample with satisfactory results.     

Flow injection analysis: Rayleigh light scattering technique for total protein determination

A novel flow injection analysis (FIA) method with Rayleigh light scattering (RLS) detection was developed for the determination of total protein concentrations. This method is based on the weak intensity of RLS of bromothymol blue (BB) (3',3"-dibromothymolsulfonephthalein) which can be enhanced by the addition of protein in weakly acidic solution. A common spectrofluorimeter was used as a detector. It was proved that the application of this method to quantify the total proteins in real samples by using bovine serum albumin was possible. The RLS signal was detected at lambda(ex)= lambda(em)=572 nm. The linear range was 7.0-70.0 microg mL(-1), the detection limit was 3.75 microg mL(-1), the reproducibility was 5.5% (n=7), and the sample throughput was 26 h(-1).     

Resonance Rayleigh scattering for the determination of cationic surfactants with Eosin Y

Resonance Rayleigh scattering (RRS) of cationic surfactants–Eosin Y systems and their analytical application have been studied. In aqueous solution at pH 2∼3, Eosin Y reacts with a monomer of cationic surfactants (CS), such as Zephiramine (Zeph), tetradecylpyridinium bromide (TPB), cetylpyridinium bromide (CPB), cetylpyridinium chloride (CPC) and cetyltrimethylammonium bromide (CTMAB), to form an ion associate and a new RRS spectrum appears. The spectral characteristics of the five ion associates are similar and their maximum scattering wavelengths (λ_max) are all at 313 nm. The intensity of RRS at λ_max of the ion associate is directly proportional to the concentration of CS in the range of 0∼3.0 μg/25 mL. The technique has high sensitivity for the determination of CS; their detection limit is between 5.57 ng/mL and 7.60 ng/mL depending on the CS. In this case, most metal and non-metal ions, NH₄ ⁺ and some anionic surfactants do not interfere, so that the method has a good selectivity. It can be applied to the determination of trace amounts of cationic surfactants in water samples. Received: 9 September 1998 / Revised: 17 November 1998 / Accepted: 18 November 1998     

Resonance Rayleigh scattering for the determination of cationic surfactants with Eosin Y

Resonance Rayleigh scattering (RRS) of cationic surfactants–Eosin Y systems and their analytical application have been studied. In aqueous solution at pH 2～3, Eosin Y reacts with a monomer of cationic surfactants (CS), such as Zephiramine (Zeph), tetradecylpyridinium bromide (TPB), cetylpyridinium bromide (CPB), cetylpyridinium chloride (CPC) and cetyltrimethylammonium bromide (CTMAB), to form an ion associate and a new RRS spectrum appears. The spectral characteristics of the five ion associates are similar and their maximum scattering wavelengths (λ_max) are all at 313 nm. The intensity of RRS at λ_max of the ion associate is directly proportional to the concentration of CS in the range of 0～3.0 μg/25 mL. The technique has high sensitivity for the determination of CS; their detection limit is between 5.57 ng/mL and 7.60 ng/mL depending on the CS. In this case, most metal and non-metal ions, NH₄ ⁺ and some anionic surfactants do not interfere, so that the method has a good selectivity. It can be applied to the determination of trace amounts of cationic surfactants in water samples.     

Precipitation of trypsin with polymethacrylic acid

Conclusions It has been shown that the precipitation of trypsin with polymethacrylic acid results in a reversible or irreversible (after an incubation period) formation of a complex and, in the latter case, a stable, nonactive addition product can be isolated.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1895–1896, August, 1970.     

吖啶染料共振瑞利散射法测定藻酸钠

在pH8.5和6.0的BR缓冲溶液中,吖啶橙(AO)和吖啶黄(AY)等碱性吖啶染料能与藻酸钠(SA)反应形成复合物,而使其共振瑞利散射RRS急剧增强并产生新的RRS光谱,其最大散射波长位于523nm(AO体系)和485nm (AY体系),藻酸钠浓度在0.075mg/L～5.0mg/L (AO体系)、0.25mg/L～3.0mg/ L(AY体系)时与散射强度(ΔI)呈直线关系,方法具有较高的灵敏度,其检出限分别为23.8ng/mL(AO体系),6.5ng/mL (AY体系).以吖啶橙体系为例研究了共存物质的影响,表明方法选择性好.用于海带提取液中藻酸钠的测定,结果满意.