Increasing Hydrolysis Time Research Articles

Physicochemical Characterization of Microcrystalline Cellulose Extracted from Kenaf Bast

Microcrystalline cellulose (MCC) was successfully prepared from bleached kenaf bast fiber through hydrochloric acid hydrolysis. The influence of hydrolysis time (1 to 3 h) on the MCC physicochemical properties was examined. Scanning electron microscopy (SEM), X-ray diffraction (XRD), particle size analysis, Fourier transform infrared spectroscopy (FT-IR), and thermal gravimetric analysis (TGA) were utilized to characterize the isolated MCC. According to FTIR analysis, the chemical composition of MCC was not changed with the reaction time. The reaction times, however, did affect the thermal stability of MCC. The thermal stability decreased linearly with increasing hydrolysis time. The optimum hydrolysis time was determined based on the morphological, structural, and thermal properties of the kenaf bast MCC.

Extraction and characterization of Nanocellulose obtained from sugarcane bagasse as agro-waste

This study aimed to characterize nanocellulose extracted from sugarcane bagasse (SCB) by acid hydrolysis 60% (w/w) H2SO4 at 45 ◦C. The effect of hydrolysis time (20, 30 and 40 min) on the structure and properties of the nanofibers was investigated. Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD) results indicated that the hemicellulose and lignin were removed extensively in the cellulose whiskers. The morphology and dimensions of the fibers and acid-released cellulose nanowhisker (CNW) were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results showed that SCB could be used as source to obtain cellulose whiskers and they had needle-like structures. Longer hydrolysis time produced a lower yield of nanofibers; whereas the degree of crystallinity increased from 38.22% to 65.37% with increasing hydrolysis time due to removal of amorphous cellulose.

Enzymatic hydrolysis of camel milk casein and its antioxidant properties

The aim of this work was to investigate the enzymatic hydrolysis of whole casein from camel milk with proteolytic enzymes, viz. alcalase, α-chymotrypsin and papain, and to assess the antioxidant activity of hydrolysates. Casein powder was reconstituted (5% TS) and the selected enzymes were added at 1:100 (enzyme/substrate). Hydrolysis was carried out for 6 h at 55 °C for alcalase and papain and 37 °C for α-chymotrypsin, and samples were drawn at 2-h interval. The hydrolysates were analysed for pH, degree of hydrolysis (DH) and antioxidant activities, viz. 2, 2′-azinobis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS), 2, 2′-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assay. The decrease in pH of the hydrolysates was observed with the progress of hydrolysis time, and as compared to alcalase, the rate of pH decrease was higher for α-chymotrypsin and papain. The DH increased significantly (P < 0.05) up to 6 h on hydrolysis with alcalase and papain, whereas with chymotrypsinolysis, DH increased significantly (P < 0.05) up to 4 h; thereafter, a non-significant increase was observed. The antioxidant activity assessed by ABTS, DPPH and FRAP assay increased significantly (P < 0.05) with the increase in hydrolysis time as well as the degree of hydrolysis. The chymotrypsinolysis exhibited higher antioxidant activity as compared to alcalase and papain. The results obtained in this study suggested that camel milk casein could be used as an ingredient in nutraceuticals or health-oriented foods.

Improvement in Enzymatic Hydrolysis of Waste Office Paper with Chemical Pretreatment and Enzyme Loading Reduced

This work evaluates the effects of increasing hydrolysis time, enzyme loading and mass of substrate on the formation of glucose in the enzymatic hydrolysis of waste office paper, after chemical or physical pre-treatment. Initially, for this study, a factorial design 24 was applied. The type of pretreatment was the only significant effect on the glucose release. Maximum glucose concentration was less than 0.5 g/L, when physical pre-treatment was used. Physical pre-treatment was therefore discarded. A new factorial design with three factors and higher number of level of treatments (hydrolysis time—24, 48 and 72 h; enzyme loading—5.2, 7.8 and 10.4 FPU/g substrate; mass of waste office paper—2.25, 3.00 and 3.75 g) was applied, after chemical pre-treatment. The increase in mass of paper increased the glucose concentration. On the other hand, the increase time of hydrolysis or enzyme loading did not influence glucose release. Maximum glucose concentration (23 g/L) was about 50 times higher than that obtained when physical pretreatment was used, reducing by half the enzyme load. Optimum conditions of enzymatic hydrolysis was obtained at 24 h of hydrolysis, using lower enzyme loading (5.2 FPU/g) and higher mass of waste office paper (3.75 g; 7.5 % w/V), after chemical pre-treatment.

Enzymatic hydrolysis of camel milk proteins and its antioxidant properties

Camel milk proteins were hydrolysed with alcalase, α-chymotrypsin and papain and hydrolysates were assessed for antioxidant activity. Non-fat camel milk (NFCM) powder was reconstituted (5% TS) in phosphate buffer and enzymes were added at a ratio of 1:100 (enzyme: substrate). Hydrolysis was carried out at 55oC for Alcalase and Papain, and 37oC for α-Chymotrypsin for 6 hours and samples were drawn at 2h interval. The hydrolysates were analysed for change in pH, degree of hydrolysis (DH) and antioxidant activities viz. 2, 2′ azino bis (3 ethylbenzthiazoline 6 sulphonic acid) (ABTS), 2,2′ diphenyl 1 picrylhydrazyl (DPPH) and ferric reducing antioxidant power assay (FRAP). With the progress of hydrolysis time, pH of the hydrolysates were decreased and higher rate was observed for alcalase. The DH increased significantly (p<0.05) upto 6 h on hydrolysis with alcalase and papain, whereas upto 4h for chymotrypsin. In SDS-PAGE, the disappearance of major protein bands in hydrolysates samples confirm hydrolysis and production of low molecular weight peptides. The antioxidant activity was assessed by ABTS, DPPH and FRAP assay, increased significantly (p<0.05) with the increase in hydrolysis time and DH. The hydrolysis carried by chymotrypsin exhibited higher antioxidant activity as compared to alcalase and papain. The results suggested that camel milk proteins could be used as natural source of protein to produce hydrolysates with antioxidant activities and can be used for human consumption and as ingredient in nutraceutical and pharmaceuticals and also in health oriented food products.

Surface-Functionalized Biodegradable Nanoparticles Consisting of Amphiphilic Graft Polymers Prepared by Radical Copolymerization of 2-Methylene-1,3-Dioxepane and Macromonomers.

Biodegradable polyester-based nanoparticles were prepared by the precipitation of amphiphilic graft copolymers, which were prepared by the ring-opening radical copolymerization of 2-methylene-1,3-dioxepane (MDO) and amphiphilic macromonomers. The diameter of the nanoparticles was controlled by the degree of grafting and the molecular weight of the grafting oligomer. PMDO-g-poly(ethylene glycol) nanoparticles were degraded by the alkaline hydrolysis of the polyester backbone. Although the colloidal stability of nanoparticles was retained due to the reorientation of the PEG chains during hydrolysis, the size of the nanoparticles decreased with increasing hydrolysis time. We also prepared PMDO-g-poly(N-isopropylacrylamide) nanoparticles, which show aggregation in response to increasing temperature.

Mechanism and kinetics of titanium hydrolysis in concentrated titanyl sulfate solution based on infrared and Raman spectra

The titanium hydrolysis in the concentrated titanyl sulfate solution is essential to the TiO2 production by using the new NaOH roasting method proposed by authors, which is undergoing to scale up. The experimental titanium hydrolysis was detected by the infrared and Raman spectra for the first time to reveal the significant role of SO42− ions. The bridging bidentate SO42− ligands arrange the Ti–O octahedra of hydrated titanium dioxide (HTD) in zigzag chains along the crystal face (221) to form anatase structure and are changed into unidentate SO42− ligands and free bisulfate ions step by step with increasing hydrolysis time. This proposed mechanism of titanium hydrolysis in titanyl sulfate solution was applied to establish a new kinetic model x=1−kne−kn(12kmCTi0+t)2kmCTi0[Ei(knt+kn2kmCTi0)−Ei(kn2kmCTi0)]−e−knt, which indicates the important effect of initial concentrations of titanium, sulfuric acid, and water on the titanium hydrolysis. The hydrolysis kinetic model is capable of describing the behavior of the system and can provide basic knowledge for scale-up of TiO2 production.

Influence of Enzymatic Hydrolysis on the Nutritional, Functional and Antioxidant Properties of Protein Hydrolysates Prepared from Seinat (Cucumis melo var. tibish) Seeds

The effect of enzymatic hydrolysis time on nutritional, functional properties and antioxidant activities of seinat seed protein isolates were studied. Hydrolysates of seinat seed protein isolates (HSSPIs) were prepared at different time (30-180 min), using two food-grade proteases. Trypsin was applied in the first hydrolysis stage followed by Pepsin. The hydrolysis time showed significant differences (p<0.05) on nutritional parameters such as essential amino acid score, essential amino acid index, biological value and predicted protein efficiency ratios. All the functional properties studied decreased as hydrolysis time increases. Antioxidant activities; (DPPH radical scavenging, ABTS radical scavenging and ferrous chelating) of HSSPIs increased with increase in hydrolysis time. Large amounts of small-sized peptides (3,000-5,000 Da) were observed with decreased as hydrolysis time increased (2.07-1.28%). The results in this study indicated that increase in hydrolysis time has positively affected nutritional and antioxidant properties of HSSPIs, but had a negative impact on the functional properties studied.

Production and Characterization of Protein Hydrolyzate from \'Bibisan Fish\' (Apogon Albimaculosus) as an Indigenous Flavor by Enzymatic Hydrolysis

This study aimed to product and characterize the physico-chemical and functional properties of protein hydrolysate bibisan fish by enzymatic hydrolysis using enzyme of biduri and papain. The results of physical analysis show yield of protein hydrolysates from bibisan fish ranged from 13.542% to 18.165%. Colors on protein hydrolyzate of bibisan fish, indicating decreasing enzyme of biduri, so hydrolysate colors is increasingly not bright. Chemical analysis show low moisture content (9-10%) and least lipid (0.03%) content. Protein content of around (63-75%). Level of rancidity fish protein hydrolysate ranged from 0.19 mmol/kg to 0.23 mmol/kg. Value of fish hydrolyzate Maillard products at various concentrations around 0.54-0.74. DH increased with increasing hydrolysis time around 6.77 to 11.98%. The results of WHC, in water absorption from 89.01 to 103.32%. While most high oil absorption capacity range around 68.06-80.09%. Amide I and II bands of protein hydrolysate appeared at the wavenumber of 1654.81 and 1548.73/cm. N-H stretching band appeared at 3292/20 cm.

Formation of uniform large SBA-15 microspheres via spray drying

The effects of inlet drying temperature, initial solute content, hydrolysis time of the precursor, and the choice of solvent were analysed in the synthesis of large (∼50 μm) and uniform SBA-15 microspheres via spray drying. Higher temperatures led to microspheres with larger particles sizes due to a faster evaporation rate. Meanwhile, particle size was proportional to the solute content, thus SBA-15 microspheres with tuneable particle size over a wide range were obtained. Highly ordered mesostructures were assembled for SBA-15 microspheres obtained from initial solute contents between 5 and 12 wt%. Solute contents of lower than 5 wt% or higher than 12 wt% lead to less ordered mesostructures. Increasing hydrolysis time of the precursor solution from 1 hour to 2 hours allowed more cross-linking of silica, thus increasing surface tension forces and resulting in hollow, “bowl-like” particles. Notably, highly oriented mesopores were developed in the “bowl-like” particles. The use of water instead of ethanol as a solvent resulted in disordered “worm-like” mesostructure, with “bowl-like” particles due to the slower evaporation rate. The unique set up of our spray dryer enabled the collection of particles immediately after spray drying. Analyses via SAXS and TEM indicated that the mesostructures were still mobile immediately after spray drying, confirming the so-called “wet-pocket” phenomenon that determined the final mesostructures.

Effect of Drying Methods on Odorous Compounds and Antioxidative Activity of Gelatin Hydrolysate Produced by Protease from B. amyloliquefaciens H11

Gelatin hydrolysates with antioxidative activity produced by protease from Bacillus amyloliquefaciens H11 with different hydrolysis times were prepared. Alpha-amino group content and antioxidative activities increased with increasing hydrolysis time (p < 0.05). When gelatin hydrolysate prepared with hydrolysis time of 3 h (GH-3H) was subjected to freeze drying and spray drying, the powder obtained from spray drying showed a decrease in antioxidant activity as measured by DPPH and ABTS radical scavenging activities, ferric-reducing antioxidant power, and metal chelating activity. Spray-dried gelatin hydrolysate (GH-3H-SD) showed higher whiteness with lower fishy odor and off-odor associated with fermentation. This was concomitant with the decreases in several odorous compounds in the sample, except for nonanal, which was higher in comparison with the powder obtained by freeze drying. Thus, spray drying could be an effective drying method to improve color and reduce undesirable odor of gelatin hydrolysate.

Acid modification of wheat, potato, and pea starch applying gentle conditions—impacts on starch properties

Acid‐thinned wheat, potato, and pea starch products were systematically prepared applying gentle conditions with variation of acid type (HCl and H2SO4), acid concentration (0.36 and 0.72 N in a 40% (w/w) suspension) as well as hydrolysis time (4 and 24 h). Starch granule properties as well as molecular and rheological characteristics in the solution state were analyzed and the impact of all parameters varied was found to be immense. Carbohydrate solubilization of wheat and potato starch was significantly higher compared to pea starch. Noteworthy progress in solubilization was found when hydrolyzed with HCl, and with increasing acid concentration and increasing hydrolysis time by trend. The hydrolysis affected the reduction of the hot paste viscosity most dominant in the first period of treatment (0–4 h), however, size exclusion chromatography‐multi angle laser light scattering (SEC‐MALS) analysis revealed a more prominent molecular degradation during the second period (4–24 h). This observation led to the interpretation that the molecular degradation in the initial phase results particularly in “debranching” of the high molar mass amylopectin fraction and lower hot paste viscosity. Continued hydrolysis with significant reduction of the molecular size, however, had reduced impact on further lowering of viscosity. SEM micrographs displayed intact pea starch granules with unchanged surface after hydrolysis, whereas wheat and potato starch granules were visibly affected with damage not evenly distributed but a variation over the granule population. Granular wheat and potato starch exhibited significantly enhanced particle size after short period modification measured in water. However, this was found eliminated at extended hydrolysis time. Reasons were hydrolysis induced molecular rearrangement resulting in better crystalline packing on the amorphous/crystalline threshold reducing the ability to swell, and the progress in granular erosion. That was in line with changed swelling characteristics determined using DSC. The study gave evidence for strong impact of acid hydrolysis on functional properties like water binding.

Structural characterization of Astragalus polysaccharides using partial acid hydrolysis-hydrophilic interaction liquid chromatography-mass spectrometry

Water-soluble polysaccharides from traditional Chinese medicine (TCM) have properties of broad-spectrum treatment and low toxicity, making them as important components in natural medicines and health products. In order to solve the problem of polysaccharides characterization caused by their complex structures, a "bottom-up" approach was developed to complete the characterization of polysaccharides from Astragalus. Firstly, Astragalus pieces were extracted with hot water and then were precipitated by ethanol to obtain Astragalus polysaccharides. Secondly, a partial acid hydrolysis method was carried out and the effects of time, acid concentration and temperature on hydrolysis were investigated. The degree of hydrolysis increased along with the increase of hydrolysis time and acid concentration. The temperature played a great role in the hydrolysis process. No hydrolysis of the polysaccharides occurred at low temperature, while the polysaccharides were almost hydrolyzed to monosaccharide at high temperature. Under the optimum hydrolysis conditions (4 h, 1.5 mol/L trifluoroacetic acid, and 80 °C), Astragalus polysaccharides were hydrolyzed to characteristic oligosaccharide fragments. At last, a hydrophilic liquid chromatography-mass spectrometry method was used for the separation and structural characterization of the polysaccharide hydrolysates. The results showed that the resulting polysaccharides were mainly 1--> 4 linear glucan, and gluco-oligosaccharides with the degrees of polymerization (DP) of 4 - 11 were obtained after partial acid hydrolysis. The significance of this study is that it is the guidance for the characterization of other TCM polysaccharides.

Preparation and characterization of cellulose nanofibers from partly mercerized cotton by mixed acid hydrolysis

Cellulose nanofibers with a diameter of 70 nm and lengths of approximately 400 nm were fabricated from partly mercerized cotton fibers by acid hydrolysis. Morphological evolution of the hydrolyzed cotton fibers was investigated by powder X-ray diffraction, Fourier transform infrared analysis and field emission scanning electron microscopy. The XRD results show that the cellulose I was partially transformed into cellulose II by treatment with 15 % NaOH at 150° for 3 h. The crystallinity of this partially mercerized sample was lower than the samples that were converted completely to cellulose II by higher concentrations of NaOH. The intensities of all of the diffraction peaks were noticeably increased with increased hydrolysis time. Fourier transform infrared results revealed that the chemical composition of the remaining nanofibers of cellulose I and II had no observable change after acidic hydrolysis, and there was no difference between the hydrolysis rates for cellulose I or II. The formation of cellulose nanofibers involves three stages: net-like microfibril formation, then short microfibrils and finally nanofibers.

The dual effects of Maillard reaction and enzymatic hydrolysis on the antioxidant activity of milk proteins

The objective of this study was to determine the enhanced effects on the biological characteristics and antioxidant activity of milk proteins by the combination of the Maillard reaction and enzymatic hydrolysis. Maillard reaction products were obtained from milk protein preparations, such as whey protein concentrates and sodium caseinate with lactose, by heating at 55°C for 7 d in sodium phosphate buffer (pH 7.4). The Maillard reaction products, along with untreated milk proteins as controls, were hydrolyzed for 0 to 3h with commercial proteases Alcalase, Neutrase, Protamex, and Flavorzyme (Novozymes, Bagsværd, Denmark). The antioxidant activity of hydrolyzed Maillard reaction products was determined by reaction with 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, their 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity, and the ability to reduce ferric ions. Further characteristics were evaluated by the o-phthaldialdehyde method and sodium dodecyl sulfate-PAGE. The degree of hydrolysis gradually increased in a time-dependent manner, with the Alcalase-treated Maillard reaction products being the most highly hydrolyzed. Radical scavenging activities and reducing ability of hydrolyzed Maillard reaction products increased with increasing hydrolysis time. The combined products of enzymatic hydrolysis and Maillard reaction showed significantly greater antioxidant activity than did hydrolysates or Maillard reaction products alone. The hydrolyzed Maillard reaction products generated by Alcalase showed significantly higher antioxidant activity when compared with the other protease products and the antioxidant activity was higher for the whey protein concentrate groups than for the sodium caseinate groups. These findings indicate that Maillard reaction products, coupled with enzymatic hydrolysis, could act as potential antioxidants in the pharmaceutical, food, and dairy industries.

High Char-Yield in AN-AM Copolymer by Acidic Hydrolysis of Homopolyacrylonitrile

Acrylonitrile (AN)-acrylamide (AM) copolymers were prepared by nitric acidic hydrolysis of homopolyacrylonitrile. The acrylamino group increased as a function of hydrolysis time, while crystallinity decreased. Differential scanning calorimetry and a thermal gravimetric analysis indicated that the acylamino introduced by acidic hydrolysis effectively enhanced the cyclization reaction at low temperature due to the change of the cyclization reaction mechanism. Char-yield of AN-AM copolymers also gradually increased with increasing hydrolysis time. The maximum char-yield was 49.48% when hydrolized at <TEX>$23^{\circ}C$</TEX> in 65% nitric acid solution for 18 h, which was 30% higher than that of non-acidic hydrolysis of homopolyacrylonitrile. Simulation of the practical process also showed an increase of char yields, where the char yields were 55.43% and 62.60% for homopolyacrylonitrile and copolyacrylonitrile, respectively, with a hydrolysis time of 13 h.

Antioxidant Properties of Deer Blood Hydrolysate and the Possible Mode of Action

Deer blood was hydrolyzed using Alcalase with hydrolysis time ranged form 0 to 6 h, and the degree of hydrolysis (DH) of protein hydrolysates increased with increasing hydrolysis time (P &lt; 0.05). The reducing power, radicals scavenging activities and Cu2+-chelation ability of deer blood hydrolysate (DBH) significantly enhanced with increasing hydrolysis time (P &lt; 0.05). The antioxidant activity of DBH, indicated by thiobarbituric acid-reactive substance (TBARS) values in a liposome-oxidizing system, increased with increasing DH (P &lt; 0.05). The results indicated that antioxidant activity of DBH depended on hydrolysis time, and the hydrolyzed deer blood could be a potent food antioxidant.

Combined Effect of Protease and Phytase on the Solubility of Modified Soy Protein

Soy protein isolate (SPI) was subjected to enzymatic hydrolysis with protease and phytase, and the solubilities of the modified SPIs (MSPIs) were characterized and compared with those of a commercial modified protein (SUPRO 670 IP from the Solae Company, St. Louis, MO). The solubilities of MSPIs showed a typical pH-dependent curve, shifting upward with an increase of hydrolysis time and enzyme dose. In particular, the solubility at pH 4.5 of the MSPI with degree of hydrolysis of 9.8% increased 9.7-fold more than SPI. Furthermore, the combined enzymatic treatment (protease and phytase) led to a significantly increased solubility of SPI at pH 4.5, which improved by 11.5-fold and 1.8-fold more than SPI and SUPRO 670 IP, respectively. In conclusion, the use of hydrolytic enzymes to synergistically improve solubility in the acidic range of pH may provide a positive impact on the MSPIs as a multifunctional food ingredient. Practical Applications Even though soy protein isolates (SPIs) are used in food industry because of their beneficial health effects as well as specific functional properties, the applications of SPIs to processed foods under acidic conditions are very limited. In this study, SPIs were modified by each or combined enzymatic treatments and their solubilities were compared in a wide range of pH. The solubility of the modified SPI (MSPI) was significantly improved compared with the commercial product. Therefore, the MSPI with enhanced solubility at acidic pH could be used in an extended range of processed foods.

Process optimisation and physicochemical characterisation of enzymatic hydrolysates of proteins from co‐products of Atlantic Salmon (Salmo salar) and Yellowtail Kingfish (Seriola lalandi)

SummaryThe aim of this study was to develop an enzymatic hydrolysis process of protein co‐products for two major commercial fish species in Australia: Atlantic salmon (AS) and Yellowtail kingfish (YTK). The outcomes are to produce high protein recovery of fish protein hydrolysates within controlled molecular weight ranges that display enhanced physicochemical properties of oil binding and emulsification. Three enzymes (Flavourzyme, Neutrase and Alcalase) were applied to processing co‐products. Protein recovery and physicochemical properties were evaluated with increasing hydrolysis time from 30 min to 180 min and ratio of enzyme to substrate (E/S) from 0.5% to 3.0%. In order to achieve a product with optimum emulsifying capacity (50 ± 0.6 m2 g−1), an E/S ratio of 0.6–1.3% Flavourzyme was applied for 30–111 min with a protein recovery of 55%; in order to achieve a product with optimum oil‐binding capacity (8.3 ± 0.3 g oil g hydrolysates−1), an E/S ratio of 2.3–3.0% Flavourzyme was applied for 25–64 min with a protein recovery of 70%. YTK protein hydrolysates were further membrane‐fractionated into five fractions (&gt;100 kDa, 50–100 kDa, 30–50 kDa, 10–30 kDa and &lt;10 kDa), and of these, the 10–30 kDa exhibited the best properties of oil binding (19 ± 0.3 g oil g hydrolysates−1) and emulsification (57 ± 0.7 m2 g−1). These results demonstrate the importance of enzymatic hydrolysis of seafood co‐products into high‐value ingredients for food products and processing.

Bis[3-(trimethoxysilyl)propyl]amine 커플링제로 개질된 실리카 나노입자의 실란화도 정량 분석

본 연구에서는 실리카 나노입자의 표면을 실란 커플링제인 bis[3-(trimethoxysilyl)propyl]amine(BTMA)을 사용하여 개질하였다. BTMA의 가수분해 시간, 농도 및 개질 시간의 변화가 실리카 표면 개질 반응에 미치는 영향을 Fourier transform infrared spectroscopy(FTIR), elemental analysis(EA) 및 고체 상태 cross-polarization magic angle spinning(CP/MAS) nuclear magnetic resonance spectroscopy(NMR)법을 사용하여 분석을 수행하였다. 연구결과 BTMA의 가수분해 시간, 농도 및 표면 개질 시간이 증가할수록 3737 <TEX>$cm^{-1}$</TEX>에 나타나는 실리카의 고립 실란올(isolated silanol) 피크의 세기는 점점 약해지고, 도입되는 BTMA의 <TEX>$-CH_2$</TEX> 기에 의한 신축(stretching) 및 굽힘(bending) 진동 피크는 점점 강하게 나타났다. EA 분석을 통한 N 및 C의 함량에서도 같은 경향을 나타내었다. BTMA를 사용한 실리카 입자의 처리 조건 중, BTMA의 농도 변화는 실리카 입자 표면과 반응하는 BTMA의 양에 큰 영향을 미치지만, BTMA의 가수분해 시간 및 표면 개질 반응 시간의 영향은 크지 않은 것으로 나타났다. In this study, we treated silica nanoparticles with bis[3-(trimethoxysilyl)propyl]amine (BTMA) silane coupling agent to modify their surfaces. We investigated the effects of BTMA hydrolysis time, BTMA concentration and BTMA treatment time on the degree of silanization reaction of silica nanoparticles. We used Fourier transform infrared spectroscopy (FTIR), elemental analysis (EA) and solid state cross-polarization magic angle spinning (CP/MAS) nuclear magnetic resonance spectroscopy (NMR) to obtain quantitative data. We found the decrease of isolated Si-OH peak intensity at 3747 <TEX>$cm^{-1}$</TEX> and the increase of <TEX>$-CH_2 $</TEX>stretching and bending peaks with increasing hydrolysis time, concentration and treatment time of BTMA. EA analysis results also supported this trend. We found a strong effect of BTMA concentration on the degree of silanization of the silica particles, but weak effects of the hydrolysis time and the treatment time.